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Tissue perforation and penetration by dorsal fin spines of spotted ratfish (Hydrolagus colliei) were responsible for the death of seven harbor seals (Phoca vitulina) in Washington State (USA) between 2006 and 2011. In six animals, necropsy revealed spines or spine parts that had perforated the esophagus or stomach and migrated into vital tissues, resulting in hemothorax, pneumothorax, pleuritis, and peritonitis. In a seventh case, a ratfish spine was recovered from the mouth of a harbor seal euthanized due to clinical symptoms of encephalitis. Gross examination revealed an abscess within the left cerebrum, which was attributed to direct extension of inflammatory infiltrate associated with the ratfish spine. Between 2009 and 2011, spotted ratfish spines were also recovered from the head or neck region of three Steller sea lions (Eumetopias jubatus) and one California sea lion (Zalophus californianus). Ratfish-related trauma appears to be a novel mortality factor for harbor seals in Washington State and could be related to increased ratfish abundance and a shifting prey base for harbor seals.
Foraging profitability can be strongly affected by the size structure of different prey, so that predator distributions are not a simple function of total prey biomass. For a bottom-feeding avian predator, the surf scoter Melanitta perspicillata, we assessed effects of prey size and other prey attributes on seasonal shifts in scoter use of 2 major foraging habitats in Puget Sound, Washington, USA. During early winter, many thousands of scoters fed at an unvegetated site where profitable prey appeared limited to mussels Mytilus trossulus of smaller sizes (2 to 30 mm) despite their much lower biomass relative to larger mussels and several other prey types. Accordingly, scoter numbers decreased at that site as small mussels declined over winter. During pre-migratory fattening in spring and feather molt in summer, >8000 surf scoters aggregated at a seagrass site where they fed mainly on epifaunal crustaceans (50 to 73%) and gastropods (12 to 27%). Body sizes of most crustacean prey had increased substantially since winter. Thus, prey size had opposite effects on the profitability of unvegetated habitats that provide mainly mussels (smaller items likely reduce shell processing costs) versus seagrass crustaceans (larger items are likely more visible and yield greater energy per prey item, although relative mobility of prey can alter their value). Total prey biomass, and prey distributions relative to water and sediment depths, appeared less important than prey size to shifts in scoter diets and numbers. Our synthesis of past studies indicates that biomass and production of mussel beds are typically an order of magnitude greater than for entire assemblages of seagrass macroinvertebrates. However, because of seasonal shifts in prey size structure, seagrass sites can be an important complement to mussel beds when the narrow size fraction of mussels that are profitable to scoters declines.
Feeding by gray whales Eschrichtius robustus along the eastern Pacific coast between the Bering Sea and Baja, Mexico, appears to be increasing. Gray whale feeding can disturb large fractions of intertidal and shallow subtidal sediments, altering the distributions of benthic invertebrates for many months. Increased gray whale feeding may be modifying foraging profitability for other bottom-feeding vertebrates along the coast, but such effects have not been documented. This paper is the first report of a feeding association between a cetacean and bottom-feeding birds, namely a migrating gray whale and diving sea ducks. Local counts and condition of surf scoters Melanitta perspicillata in Puget Sound, Washington, suggest that gray whale feeding can provide important foraging opportunities for scoters during spring, when other foods may have declined and requirements to prepare for migration and reproduction are high. Complementary data are needed to evaluate the importance to scoters of this seasonal interaction with gray whales. However, given the large and protracted impacts of gray whales on benthic communities, our observations suggest that whale feeding may have increasing influence on the foraging patterns and trophic relations of a range of bottom-feeding vertebrates.
Identifying important foraging sites for highly mobile marine predators has relied mainly on relating their distributions to broadly defined habitat data. However, understanding functional dependencies on foraging sites also requires knowledge of the relative contributions of foods to predator condition. We coupled predator distributions with measures of their diet and condition to assess the importance of Pacific herring Clupea pallasii spawning events to 2 closely related and declining sea duck species. In Puget Sound, Washington, the numerical response of scoters to spawn increased with increasing biomass of spawning herring; this response was 4-fold greater for surf scoters Melanitta perspicillata than for white-winged scoters M. fusca after accounting for local differences in their abundances. In the Strait of Georgia, British Columbia, diets estimated from fatty acids and stable isotopes indicated that both scoter species gained mass by consuming spawn during late March to early April. At a site without spawn during this period, only male white-winged scoters gained mass. In contrast, body mass of male surf scoters declined appreciably before spawn became available in one study year, suggesting greater dependence on spawn for restoring depleted reserves. From winter to spring, surf scoters attained greatest body mass during late April to mid-May while migrating through southeast Alaska; during this period, plasma triglycerides suggested that fattening was not related solely to spawn consumption, yet surf scoters aggregated to consume spawn whenever it was available. Although it is not clear whether herring are essential to their population processes, surf scoters and a range of other predators for which spawning areas are clearly preferred foraging sites would likely benefit from efforts that preserve declining herring stocks.
Killer whales (Orcinus orca) are widely distributed throughout the world’s oceans, yet little has been documented about their stranding patterns. Knowledge of stranding patterns improves our ability to examine and sample carcasses and provides a foundation for understanding killer whale natural history, diet, reproduction, anthropogenic stressors, emerging diseases, and patterns of unusual mortality. We compiled published and unpublished killer whale stranding data to describe stranding patterns in the North Pacific Ocean. Between 1925 and 2011, 371 stranded killer whales were reported in Japan (20.4%), Russia (3.5%), Alaska (32.0%), British Columbia (27.4%), Washington (4.0%), Oregon (2.7%), California (5.1%), Mexico (3.8%), and Hawaii (0.8%). Strandings occurred at all times of year, but regionally specific seasonal differences were observed. Mortality and annual census data from Northern and Southern Resident populations were extrapolated to estimate that across the North Pacific, an average of 48 killer whales die annually. However, over the last two decades, an average of only 10 killer whale carcasses were recovered annually in this ocean, making each event a rare opportunity for study. Publication of a standardized killer whale necropsy protocol and dedicated funding facilitated the number of complete postmortem necropsies performed on stranded killer whales from 1.6% to 32.2% annually.
The Devil’s Mountain Fault Zone extends east to west from Washington state to just south of Victoria in the northern Juan de Fuca Strait. Recently collected geophysical data were used to map this fault zone in detail, which show the main trace, and associated primary and secondary (conjugate) faults that occur within a 6 km wide deformation zone west of the Canada/U.S.A boundary. The fault zone has been active in the Holocene as seen in the offset and disrupted upper Quaternary strata, seafloor displacement, and deformation within sediment cores taken close to the axis of the faults. Based on the length and previously estimated slip rates of the fault zone in Washington state, it appears to have a potential of producing a strong earthquake adjacent to Victoria, perhaps as large as magnitude 7.0 or greater.
Although many studies have investigated how community characteristics such as diversity and disturbance relate to invasibility, the mechanisms underlying biotic resistance to introduced species are not well understood. I manipulated the functional group composition of native algal communities and invaded them with the introduced, Japanese seaweed Sargassum muticum to understand how individual functional groups contributed to overall invasion resistance. The results suggested that space preemption by crustose and turfy algae inhibited S. muticum recruitment and that light preemption by canopy and understory algae reduced S. muticum survivorship. However, other mechanisms I did not investigate could have contributed to these two results. In this marine community the sequential preemption of key resources by different functional groups in different stages of the invasion generated resistance to invasion by S. muticum. Rather than acting collectively on a single resource the functional groups in this system were important for preempting either space or light, but not both resources. My experiment has important implications for diversity–invasibility studies, which typically look for an effect of diversity on individual resources. Overall invasion resistance will be due to the additive effects of individual functional groups (or species) summed over an invader’s life cycle. Therefore, the cumulative effect of multiple functional groups (or species) acting on multiple resources is an alternative mechanism that could generate negative relationships between diversity and invasibility in a variety of biological systems.
Introduced algae have become a prominent component of the marine flora in many regions worldwide. In the NE Pacific, the introduced Japanese alga Sargassum muticum (Yendo) Fensholt is common and abundant in shallow, subtidal, rocky habitats, but its effects on subtidal, benthic communities in this region have not previously been studied. I measured the response of native species to experimental manipulation of S. muticum in field experiments in the San Juan Islands of Washington State. Native canopy (brown) and understory (red) algae were more abundant in plots from which S. muticum had been removed, and the native kelp Laminaria bongardiana (the most abundant species of brown alga in the absence of S. muticum) grew more than twice as fast in plots where S. muticum was absent. The negative effects of S. muticum on native algae appear to be a result of shading, rather than changes in water flow, sedimentation, or nutrient availability. S. muticum also had a strongly negative indirect effect on the native sea urchin Stronglyocentrotus droebachiensis by reducing abundances of the native kelp species on which it prefers to feed. My results indicate that S. muticum has a substantial impact on native communities in this region, including effects at multiple trophic levels. Because of their worldwide distribution and capacity to alter native communities, non-indigenous algae are potentially important agents of global ecological change.
Abstract: The effectiveness of marine protected areas (MPAs) and their effects on the predators of target species have been a matter of discussion for some time. In the Salish Sea, a number of MPAs protect several species of rockfish (Sebastes spp.), three of which are currently listed under the Endangered Species Act (ESA); however, the role of coastal river otter (Lontra canadensis) predation on rockfish populations is poorly understood. This study describes the scarcely studied diet of river otters in the San Juan Islands, Washington, as a first step in assessing the potential effect of these predators on rockfish. Using frequency of occurrence (% FO), we described coastal river otter diet for San Juan, Orcas, and Fidalgo Islands during the summer of 2008. River otters consumed a variety of both fish and invertebrate species. Fish occurred most frequently in their diet at all three islands, including gunnels (Pholidae) (present in 83.6 to 97.3% of scats), sculpins (Cottidae) (79.5 to 97.3%), and pricklebacks (Stichaeidae) (58.9 to 78.1%). Rockfish were present in 2.7 to 21.9% of river otter scat with the highest occurrence at San Juan Island (21.9%). Scat also contained a higher occurrence of juvenile rockfish vs adult specimens. Although rockfish consumption by river otters at San Juan Island has increased since the summer of 1999, consistent with the establishment of MPAs, we cannot attribute the establishment of MPAs as the cause or address the positive or negative potential effects of river otter predation on rockfish recovery. However, this information may assist future studies that use more modern techniques in assessing these effects on rockfish populations.
We assess the potential of using otolith chemistry to differentiate quillback rockfish (Sebastes maliger) within Puget Sound, Washington, where two distinct population segments (DPS) have been identified. Using opportunistic collections (1993–2003) of quillback rockfish (n=77; age range of 2–65 yrs.) we first sought to determine whether fish from different sites and regions could be differentiated based on the trace elemental concentrations at the edge of their otoliths (i.e., the chemical record of the fish’s recent history). Results of our quadratic discriminant function analysis (QDFA) indicated significant spatial variability for fish collected at relatively large (regions) and small (sites) spatial scales. Specifically, fish collected from regions in 2002 (San Juan Islands and southern Puget Sound) and 2003 (eastern and western Strait of Juan de Fuca) were correctly classified with 100% and 65% accuracy (based on jack-knife classification), respectively, while fish collected from sites in 1998 (Mukilteo and Foulweather) were classified with 100% accuracy. We also investigated whether we could differentiate fish that were collected from different DPS and regions by using elemental concentrations from their whole otolith (which represents environmental information over the lifetime of a fish). Results from the QDFAs indicated relatively high classification success (80%) when comparing fish collected from either different DPS (i.e., Northern Puget Sound and Puget Sound Proper DPS) or regions (i.e., western and eastern Strait of Juan de Fuca). Findings from this study highlight the value of otolith chemistry in the study of population structure of quillback rockfish in Puget Sound.
Salmonella enterica serovar Newport (Salmonella Newport) was isolated from multiple tissues in a neonate killer whale (Orcinus orca) that stranded dead in 2005 along the central coast of California, USA. Necrotizing omphaloarteritis and omphalophlebitis was observed on histologic examination suggesting umbilical infection was the route of entry. Genetic analysis of skin samples indicated that the neonate had an offshore haplotype. Salmonellosis has rarely been identified in free-ranging marine mammals and the significance of Salmonella Newport infection to the health of free-ranging killer whales is currently unknown.
The non-native tunicates Didemnum vexillum, Ciona savignyi, and Styela clava are of concern to resource managers of Puget Sound, Washington, USA because they have been shown to threaten native species diversity and shellfish aquaculture in other regions. Invasive tunicates in Puget Sound occur mainly on man-made structures such as floating docks and aquaculture facilities. We conducted studies of the three species of concern and a fourth introduced tunicate, Botrylloides violaceus, that occur on these structures to evaluate their effects on mussels and native invertebrate communities. Because most studies of community effects of tunicates have dealt with sessile fouling organisms, we focused instead on epibenthic organisms such as meiofaunal harpacticoid copepods and macrofaunal polychaetes and amphipods that are known to be important prey for juvenile salmon and other small fish. Similar studies have shown mixed results, with negative, positive, or no effects depending on the species. We also found few community-level effects. Abundances of several species were lower when tunicates were present, but only at some of the sites. Several other species, including a non-native isopod, were significantly more abundant in the presence of tunicates. However, in most cases results were not statistically significant and more intensive, controlled sampling or experiments may be needed to demonstrate any consistent tunicate effects. Although invasive tunicates cause problems for mussel growers elsewhere, we did not find negative effects on mussels at four sites in Puget Sound. Given the large impacts known to accompany tunicate invasions elsewhere and their relatively recent invasions into Puget Sound, monitoring of their populations and effects should continue in the region.
We measured persistent organic pollutant (POP) concentrations in chinook salmon (Oncorhynchus tshawytscha) in order to characterize dietary exposure in the highly contaminated, salmon-eating northeastern Pacific resident killer whales. We estimate that 97 to 99% of polychlorinated biphenyls (PCBs), polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), dichlorodiphenyltrichloroethane (DDT), and hexachlorocyclohexane (HCH) in returning adult chinook were acquired during their time at sea. Highest POP concentrations (including PCBs, PCDDs, PCDFs, and DDT) and lowest lipids were observed in the more southerly chinook sampled. While feeding by salmon as they enter some more POP-contaminated near-shore environments inevitably contribute to their contamination, relationships observed between POP patterns and both lipid content and δ13C also suggest a migration-related metabolism and loss of the less-chlorinated PCB congeners. This has implications for killer whales, with the more PCB-contaminated salmon stocks in the south partly explaining the 4.0 to 6.6 times higher estimated daily intake for ΣPCBs in southern resident killer whales compared to northern residents. We hypothesize that the lower lipid content of southerly chinook stocks may cause southern resident killer whales to increase their salmon consumption by as much as 50%, which would further increase their exposure to POPs.
The San Juan Islands National Wildlife Refuge (San Juan NWR) is comprised of 83 small islands, rocks, and reefs scattered throughout the San Juan Archipelago in the inland waters of Washington State. Current guidelines, set forth by the U.S. Fish and Wildlife Service (USFWS), advise vessels to stay 200 yards offshore from refuge sites to provide a marine buffer for birds and marine mammals who utilize the refuge (Murray, 1998). Compliance with the existing USFWS guidelines provides inherent protection to the intertidal and subtidal resources within these marine buffer zones and could arguably constitute a de facto network of marine protected areas (MPAs) in the region. This article explores how marine areas currently set aside from pbulic use and/or adjacent to upland protected areas, such as the San Juan NWR, could provide a politically feasible and cost-effective means for establishing MPAs. The idea is to build upon existing upland management by creating partnerships with other agencies and institutions in order to provide more organic management to marine areas and increase protection to the marine sources.
On February 11, 2012, a juvenile female southern resident killer whale, L-112, stranded just north of Long Beach, Washington. The whale was in good nutritional condition. Autonomous passive acoustic recorders off the coasts of Washington, Oregon and California indicated that the L subgroup to which L112 belonged were near Pt. Reyes, CA on January 30, 2011, Ft. Bragg, CA on January 31, off Westport, WA on February 5, 2012 and near Newport, OR on February 20-21, 2012. These data and drift patterns for coastal Oregon and Washington waters suggested that L-112 had likely died off northern Oregon or in the Columbia River plume. An intensive series of diagnostic studies were initiated. Gross examination revealed extensive subcutaneous bruising on the dorsolateral aspects of the head, tracking to the throat and anterior insertion of the right pectoral fin. Microscopic assessment of sampled tissues was hindered due to advanced autolysis; there was generalized gas accumulation in most major organs. Nematodes (Crassicauda sp.) were evident in the right peribullar space with associated chronic inflammation. There was mild nonspecific and multisystemic chronic inflammation. Results from extensive bacterial, viral, molecular and toxicological tests were inconclusive. Head imaging studies (CT scans) and subsequent gross dissection revealed disruption of the cerebral hemispheres with marked accumulation of clear fluid and variably extensive hemorrhage. Examination of the axial skeleton revealed incomplete ossification of the dorsal vertebral process of C7 and Computed Tomography (CT) suggested that this defect was a congenital anomaly and likely unrelated to its death. PCR of feces indicated the presence of Chinook and halibut L-112’s diet. Anisakis sp. Cf. A. simplex also were identified in the stomach. Blunt trauma to the head and neck is the prime consideration for the immediate cause of death of this whale. In contrast to initial media reports, no military activities involving sonar or explosives were undertaken in the immediate vicinity of this animal, at the time of death. There was no gross indication of fisheries interaction. While the extensive evaluations were all consistent with trauma being the cause of death, the exact type or source of the traumatic injuries remains unknown.
The transboundary Georgia Basin Puget Sound ecosystem is situated in the southwest corner of British Columbia and northwest comer of Washington State. While bountiful and beautiful, this international region is facing significant threats to its marine and freshwater resources, air quality, habitats and species. These environmental challenges are compounded by rapid population growth and attendant uiban sprawl. As ecosystem stresses amplified and partnerships formed around possible solutions, it became increasingly clear that the shared sustainability challenges in the Georgia Basin and Puget Sound required shared solutions. Federal, state and provincial institutional arrangements were made between jurisdictions, which formalized small scale interest in transboundary management of this ecosystem. Formal agreements, however, can only do so much to further management of an ecosystem that spans international boarders. A transboundary regional research meeting, the 2003 GB/PS Research Conference, opened the doors for large-scale informal cross-boarder cooperation and management. In addition to cooperation, continued efforts to stem toxic pollution, contain urban growth, and protect and restore ecosystems, require a commitment from scientists, educators and policy makers to better integrate research and science with decision-making.
Joe Gaydos reviews two books for the Spring 2014 issue of The Wildlife Professional.
Efforts are underway to restore the Salish Sea, a 16,925 km2 inland sea shared by Washington State, USA, and British Columbia, Canada. A list of the birds and mammals that use this marine ecosystem is lacking. We compiled information from varied sources and identified 172 bird and 37 mammal species that depend on the Salish Sea marine ecosystem. Of these species, 72 bird and 29 mammal species are both highly dependent on intertidal or marine habitat as well as on marine derived food. One hundred bird species and 8 mammal species that use the Salish Sea marine ecosystem have varying degrees of dependence on the marine and terrestrial ecosystems to meet significant life history needs. These interactions between the marine and terrestrial ecosystems indicate the need to integrate marine and terrestrial restoration efforts to achieve long-term conservation of the suite of birds and mammals that use and depend on the marine ecosystem. This comprehensive list of avian and mammal fauna for the Salish Sea serves as a foundation for determining the occurrence of new species and the disappearance of others, enables selection of species as indicators for ecosystem health, and also provides a basis for identifying the mechanisms responsible for marine bird and mammal declines.
Abstract not available.
This is a transcript of a talk given on March 27, 2015 to the Puget Sound Partnership Leadership Council by Joe Gaydos of the SeaDoc Society and Linda Rhodes, Ph.D of the Marine Microbes & Toxins Program of NOAA Fisheries Northwest Science Center.
Species of concern are native species, sub-species or ecologically significant units that warrant special attention to ensure their conservation. The number of species of concern within an ecosystem can be used as a crude measure of ecosystem health. Within the Salish Sea, four jurisdictions assess which species require special initiatives to ensure protection and survival of the population: the Province of British Columbia, the State of Washington, the Canadian Federal Government, and the United States Federal Government. Also known as marine species at risk, the number of species of concern in the Salish Sea is used by the US Environmental Protection Agency and Environment Canada as a transboundary ecosystem indicator. As of November 15, 2013, there were 119 species at risk in the Salish Sea, almost twice the number of species at risk when the indicator was first established in 2002. While some of this increase represents an increase in the number of fish, bird and mammal species known to use the Salish Sea, most additions represent new listings due to concern about declines in populations. In terms of species richness, currently 35% of mammal species, 32% of bird species, 17% of fish species, 100% of reptile species, and less than 1% of macro invertebrate species are listed by one or more jurisdiction. The high proportion of species of concern is suggestive of ecosystem decay and we recommend that it is time to consider the Salish Sea an ecosystem of concern.
Harbor porpoise (Phocoena phocoena) are one of the most frequently sighted cetaceans in the Salish Sea. Anecdotal information, possibly supported with stranding encounter rate data, suggests that harbor porpoise may have increased in Puget Sound, or have shifted their distribution back to Puget Sound relative to earlier decades.
On February 7, 2013, Pacific Biodiversity Institute, Cascadia Research Collective and the SeaDoc Society hosted scientists from Washington and British Columbia to determine the state of knowledge on this species and coordinate ongoing research efforts.
The group discussed what was currently known about harbor porpoise habitat needs, distribution, population trends, life cycle, genetics, behavior and role in the ecosystem. The workshop goals were to foster communication, identify the data that could be used to prepare manuscripts, determine the research that would most enhance our understanding of the harbor porpoise, seek opportunities for collaboration, and prioritize critical harbor porpoise conservation issues that need to be addressed.
An emaciated, free-ranging, sub-adult, male beaver (Castor canadensis) was found dead and was necropsied. Microscopically, the beaver had acute necrotizing hepatitis and splenitis with florid lobulated colonies of extracellular coccobacilli. Intravascular septic emboli were identified in lung, small intestine, and kidney, and discrete ulcers with scattered superficial extracellular accumulation of coccobacilli were noted on tail margins and plantar surfaces of the hind feet. Yersinia pseudotuberculosis was cultured on Columbia blood and MacConkey agar and identified by API 20E. Based on the pathology and acute mortality described in this case, as well as historical reports of Y. pseudotuberculosis related mortality in other beavers, this species could serve as a public health sentinel for localized occurrences of this bacterium.
Species of Cryptosporidium and Giardia can infect humans and wildlife and have the potential to be transmitted between these 2 groups; yet, very little is known about these protozoans in marine wildlife. Feces of river otters (Lontra canadensis), a common marine wildlife species in the Puget Sound Georgia Basin, were examined for species of Cryptosporidium and Giardia to determine their role in the epidemiology of these pathogens. Using ZnSO4 flotation and immunomagnetic separation, followed by direct immunofluorescent antibody detection (IMS/DFA), we identified Cryptosporidium sp. oocysts in 9 fecal samples from 6 locations and Giardia sp. cysts in 11 fecal samples from 7 locations. The putative risk factors of proximate human population and degree of anthropogenic shoreline modification were not associated with the detection of Cryptosporidium or Giardia spp. in river otter feces. Amplification of DNA from the IMS/DFA slide scrapings was successful for 1 sample containing > 500 Cryptosporidium sp. oocysts. Sequences from the Cryptosporidium 18S rRNA and the COWP loci were most similar to the ferret Cryptosporidium sp. genotype. River otters could serve as reservoirs for Cryptosporidium and Giardia species in marine ecosystems. More work is needed to better understand the zoonotic potential of the genotypes they carry as well as their implications for river otter health.
Feces of harbor seals (Phoca vitulina richardsi) and hybrid glaucous-winged/western gulls (Larus glaucescens / occidentalis) from Washington State’s inland marine waters were examined for Giardia and Cryptosporidium spp. to determine if genotypes carried by these wildlife species were the same genotypes that commonly infect humans and domestic animals. Using immunomagnetic separation followed by direct fluorescent antibody detection, Giardia spp. cysts were detected in 42% of seal fecal samples (41/97). Giardia-positive samples came from 90% of the sites (9/10) and the prevalence of positive seal fecal samples differed significantly among study sites. Fecal samples collected from seal haulout sites with over 400 animals were 4.7 times more likely to have Giardia spp. cysts than samples collected at smaller haulout sites. In gulls, a single Giardia sp. cyst was detected in 4% of fecal samples (3/78). Cryptosporidium spp. oocysts were not detected in any of the seals or gulls tested. Sequence analysis of a 398 bp segment of G. duodenalis DNA at the glutamate dehydrogenase locus suggested that 11 isolates originating from seals throughout the region were a novel genotype and 3 isolates obtained from a single site in south Puget Sound were the G. duodenalis canine genotype D. Real-time TaqMan PCR amplification and subsequent sequencing of a 52 bp small subunit ribosomal DNA region from novel harbor seal genotype isolates showed sequence homology to canine genotypes C and D. Sequence analysis of the 52 bp small subunit ribosomal DNA products from the 3 canine genotype isolates from seals produced mixed sequences at could not be evaluated.
Two pilot trials and one study in a closely related grebe species suggest that Western grebes (Aechmophorus occidentalis) will not tolerate intracoelomic transmitter implantation with percutaneous antennae and often die within days of surgery. Wild Western grebes (n = 21) were captured to evaluate a modified surgical technique. Seven birds were surgically implanted with intracoelomic transmitters with percutaneous antennae by using the modified technique (transmitter group), 7 received the same surgery without transmitter implantation (celiotomy group), and 7 served as controls (only undergoing anesthesia). Modifications included laterally offsetting the body wall incision from the skin incision, application of absorbable cyanoacrylate tissue glue to the subcutaneous space between the body wall and skin incisions, application of a waterproof sealant to the skin incision after suture closure, and application of a piece of porcine small intestine submucosa to the antenna egress. Survival did not differ among the 3 groups with 7 of 7 control, 6 of 7 celiotomy, and 6 of 7 transmitter birds surviving the 9-day study. Experimental birds were euthanized at the end of the study, and postmortem findings indicated normal healing. Significant differences in plasma chemistry or immune function were not detected among the 3 groups, and only minor differences were detected in red blood cell indices and plasma proteins. After surgery, the birds in the transmitter group spent more time preening tail feathers than those in the control and celiotomy groups. These results demonstrate that, in a captive situation, celiotomy and intracoelomic transmitter implantation caused minimal detectable homeostatic disturbance in this species and that Western grebes can survive implantation of intracoelomic transmitters with percutaneous antennae. It remains to be determined what potential this modified surgical procedure has to improve postoperative survival of Western grebes that are intracelomically implanted with transmitters with percutaneous antennae and released into the wild.
SPILLOVER FROM DOMESTIC ANIMALS TO WILDLIFE
There are multiple documented cases where CDV has been transmitted from domestic dogs to wildlife and additional instances where CDV in wildlife is believed to have come from domestic dogs. Both of the 1987 and 2000 CDV epizootics in Baikal and Caspian seals, respectively, likely originated from CDV epizootics in domestic dogs. Viral homology of the CDV H gene in a CDV-infected wild wolf and domestic dog suggest that domestic dogs were responsible for transmitting CDV to wild wolves in Portugal in 2007-2008.6 Between 2001 and 2003 an epizootic of CDV in black-backed jackals and other wild carnivores in Namibia was attributed to domestic dogs based on viral sequence data from the P and H genes. A CDV epizootic in domestic dogs in Kenya between 1990 and 1992 is believed to have been responsible for the disappearance of known packs of African wild dogs in the region. Also, it has been hypothesized that domestic dogs could have transmitted CDV to wild giant pandas in Wolong Reserve, China.
VACCINE-INDUCED DISEASE IN WILDLIFE
Vaccine-induced canine distemper has been demonstrated in numerous wildlife species including the African wild dog, black-footed ferret, kinkajou, lesser panda, maned wolf, and gray fox. Suspected vaccineinduced canine distemper has occurred in raccoons, fennec fox, and the South American bush dog. All have been associated with administration of various modified live vaccines.
Infectious diseases have the potential to play a role in the decline of threatened wildlife populations, as well as negatively affect their long-term viability, but determining which infectious agents present risks can be difficult. The southern resident killer whale, Orcinus orca, population is endangered and little is known about infectious diseases in this species. Using available reference literature, we identified 15 infectious agents (bacteria, viruses, and fungi) reported in free-ranging and captive killer whales, as well as 28 additional infectious agents reported in free-ranging and captive odontocete species sympatric to southern resident killer whales. Infectious agents were scored as having a high, medium, or low ability to affect fecundity or reproductive success, to cause disease in individual animals, and to cause epizootics. Marine Brucella spp., cetacean poxvirus, cetacean morbilliviruses, and herpesviruses were identified as high priority pathogens that warrant further study. Using identified pathogens to develop a standardized necropsy and disease testing protocol for southern resident killer whales and sympatric odontocetes will improve future efforts to better understand the impacts of priority and non-priority infectious agents on southern resident killer whales. This model can be used to evaluate potential infectious disease risks in other threatened wildlife populations.
Despite the merit of managing natural resources on the scale of ecosystems, evaluating threats and managing risk in ecosystems that span multiple countries or jurisdictions can be challenging. This requires each government involved to consider actions in concert with actions being taken in other countries by co-managing entities.
Multiple proposed fossil fuel-related and port development projects in the Salish Sea, a 16,925 km2 inland sea shared by Washington State (USA), British Columbia (Canada), and Indigenous Coast Salish governments, have the potential to increase marine vessel traffic and negatively impact natural resources.
There is no legal mandate or management mechanism requiring a comprehensive review of the potential cumulative impacts of these development activities throughout the Salish Sea and across the international border.
This project identifies ongoing and proposed energy-related development projects that will increase marine vessel traffic in the Salish Sea and evaluates the threats each project poses to natural resources important to the Coast Salish.
While recognizing that Coast Salish traditions identify all species as important and connected, we used expert elicitation to identify 50 species upon which we could evaluate impact. These species were chosen because Coast Salish depend upon them heavily for harvest revenue or as a staple food source, they were particularly culturally or spiritually significant, or they were historically part of Coast Salish lifeways.
We identified six development projects, each of which had three potential impacts (pressures) associated with increased marine vessel traffic: oil spill, vessel noise and vessel strike. Projects varied in their potential for localized impacts (pressures) including shoreline development, harbor oil spill, pipeline spill, coal dust accumulation and nearshore LNG explosion.
Based on available published data, impact for each pressure/species interaction was rated as likely, possible or unlikely. Impacts are likely to occur in 23 to 28% of the possible pressure/species scenarios and are possible in another 15 to 28% additional pressure/species interactions.
While it is not clear which impacts will be additive, synergistic, or potentially antagonistic, studies that manipulate multiple stressors in marine ecosystems suggest that threats associated with these six projects are likely to have an overall additive or even synergistic interaction and therefore impact species of major cultural importance to the Coast Salish, an important concept that would be lost by merely evaluating each project independently. Failure to address multiple impacts will affect the Coast Salish and the 7 million other people that also depend on this ecosystem.
These findings show the value of evaluating multiple threats, and ultimately conducting risk assessments at the scale of ecosystems and highlight the serious need for managers of multinational ecosystems to actively collaborate on evaluating threats, assessing risk, and managing resources.
Harbor seal (Phoca vitulina richardii) populations in the inland waters of Washington and British Columbia are at or near carrying capacity. Stranded pups often are collected and admitted to rehabilitation centers, and then released when they reach a weight of 22 kg and meet a variety of preestablished health and release conditions. While rehabilitation is common practice, it is unclear if rehabilitated seal pups behave like wild weaned pups. Using satellite transmitters, we compared movement patterns of 10 rehabilitated pups with 10 wild weaned pups. When released, rehabilitated seals were longer and heavier than wild pups, while wild pups had a larger mean axillary girth. No clinically different blood parameters were detected. On average, rehabilitated harbor seal pups traveled nearly twice as far cumulatively, almost three times as far daily, and dispersed over three times as far from the release site compared to wild weaned seals. Additionally, wild harbor seals transmitted nearly twice as long as did rehabilitated seals. These patterns suggest that learned behavior during the brief 3–4 wk nursing period likely enables wild harbor seal pups to move less daily and remain closer to their weaning site than rehabilitated pups.
North American river otters (Lontra canadensis; referred to simply as river otters from here on) are widely distributed across North America with the exception of the desert Southwest. Extirpated over much of their original range, reintroduction programs in 21 states have been extensive and river otters now occupy at least portions of their historic range in every state within the continental United States except New Mexico. Over most of their range they can be found in freshwater habitats ranging from alpine lakes to rivers, streams and swamps. From California to Alaska, they also occupy a nearshore marine habitat where they primarily feed on marine invertebrates and fishes and play and important ecological role moving marine nitrogen and phosphorus into nearshore vegetation. Their dependence on freshwater for drinking, however, limits them to marine habitats close land where freshwater is available. With river otter populations recovering, veterinarians have an increased chance to encounter them in both wildlife management and rehabilitation settings. Clinicians working with river otters should be familiar with their clinical anatomy and diseases.
An estimated 1.2 million cases of salmonellosis occur annually in the United States (approximately 42,000 are laboratory-confirmed and reported to the Centers for Disease Control; CDC). Transmission comes primarily from contaminated food, water or contact with infected animals only some of which are wild animals. Of the 50 Salmonella outbreaks reported by the CDC between 2006 and 2013, only 5 (10%) were related to wildlife. These included the 2013 outbreak related to small turtles (Salmonella Sandiego, Pomona and Poona), two 2012 events associated with hedgehogs (Salmonella Typhimurium) and small turtles (Salmonella Sandiego, Pomona and Poona), the 2011 outbreak connected to Africa dwarf frogs (Salmonella Typhimurium) and the 2010 water frog-related outbreak (Salmonella Typhimurium).
Wildlife veterinary medicine is broad in scope and practice. As a discipline, it is the purview of professors and private practitioners, ranchers and regulatory veterinarians, conservationists and curators. That said, what constitutes an urgent and compelling issue for a head veterinarian at a rehabilitation clinic may greatly differ from what creates job security for a state wildlife
veterinarian; a burning question for a wildlife health researcher at a university may be of little interest to a veterinarian who owns a farmed cervid practice. More often than not, however, perspectives and interests intersect or even converge. For example, when it comes to a problem like bovine tuberculosis in wild white-tailed deer in the upper midwest, crisis truly builds community among the seemingly disparate interests of state wildlife veterinarians, rehabilitators, ranchers, and hunters. Wildlife veterinarians as a whole share a concern for critical issues, problems, and solutions. Currently, top of mind for wildlife veterinarians around the United States, regardless of their particular jobs or focuses, are the following “Top 10” list of hot topics, new challenges, and promising solutions.
Commercial and recreational fishing gear that is accidentally lost or intentionally discarded (i.e.”derelict”) in the marine environment impacts marine life and underwater habitat worldwide, including in California. Since 2006, the California Lost Fishing Gear Recovery Project (www.lostfishinggear.org), a program of the SeaDoc Society at the UC Davis Wildlife Health Center, has removed more than 60 tons of lost commercial and recreational fishing gear and debris from California coastal waters, as well as more than one million feet of monofilament line from public-access piers. Based on successful programs in the Northwestern Hawaiian Islands, where derelict gear impacts the recovery of the endangered Hawaiian monk seal, and modeled on a similar program in Washington State, the Project contracts with commercial urchin harvesters to locate and recover lost gear utilizing SCUBA diving methods and equipment. A toll-free hotline (1-888-491-GEAR) fields citizen reports of gear loss or sightings. To date, the Project has recovered more than 1,200 lost commercial fishing nets, traps and pots entangling 690 live invertebrates (e.g. lobster, crab) and 106 live fish (e.g. sheepshead, garibaldi, sculpin, sharks and hagfish), which were rescued and released. A total of 64 organisms have been discovered dead in recovered lost gear, including 9 cormorants, 4 common dolphins and 1 California sea lion. The Project has collaborated with the Monterey Bay and Gulf of the Farallones National Marine Sanctuaries on deep water lost gear recovery, and has organized local community groups to install and maintain fishing line recycling bins on public fishing piers to encourage appropriate disposal of unwanted hooks and line. The ultimate goal of the project is to transfer lost gear recovery operations to commercial fishermen’s associations so that fishermen will serve as local leaders in lost gear recovery, garnering public support for their industry; a pilot effort has laid the groundwork for this transfer in Eureka. To better understand the impacts of lost gear on public-trust resources, the Project maintains a comprehensive database, has conducted epidemiologic research on rates of gear entanglement and ingestion in coastal wildlife, and in collaboration with the Northwest Straits Initiative, modeled the impacts of derelict nets on Dungeness crab in Puget Sound. Lost fishing gear is a proven mitigation measure that reduces risk of injury and death for coastal marine wildlife in California.
Derelict fishing gear persists for decades and impacts marine species and underwater habitats. Agencies and organizations are removing significant amounts of derelict gear from marine waters in the United States. Using data collected from repeated survey dives on derelict gillnets in Puget Sound, Washington, we estimated the daily catch rate of a given derelict gillnet, and developed a model to predict expected total mortality caused by a given net based on entanglement data collected upon its removal. We also generated a cost:benefit ratio for derelict gear removal utilizing known true costs compared to known market values of the resources benefiting from derelict gear removal. For one study net, we calculated 4,368 crab entangled during the impact lifetime of the net, at a loss of $19,656 of Dungeness crab to the commercial fishery, compared to $1358 in costs to remove a given gillnet, yielding a cost:benefit ratio of 1:14.5.
A report for the SeaDoc Society prepared by Wild Fish Conservancy, Long Live the Kings, Kwiaht, and the Washington Dept. of Fish and Wildlife Molecular Genetics Lab.
Many marine pathogens are opportunists, present in the environment, but causing disease only under certain conditions such as immunosuppression due to environmental stress or host factors such as age. In the temperate eelgrass Zostera marina, the opportunistic labyrinthu-lomycete pathogen Labyrinthula zosterae is present in many populations and occasionally causes severe epidemics of wasting disease; however, risk factors associated with these epidemics are unknown. We conducted both field surveys and experimental manipulations to examine the effect of leaf age (inferred from leaf size) on wasting disease prevalence and severity in Z. marina across sites in the San Juan Archipelago, Washington, USA. We confirmed that lesions observed in the field were caused by active Labyrinthula infections both by identifying the etiologic agent through histology and by performing inoculations with cultures of Labyrinthula spp. isolated from observed lesions. We found that disease prevalence increased at shallower depths and with greater leaf size at all sites, and this effect was more pronounced at declining sites. Experimental inoculations with 2 strains of L. zosterae confirmed an increased susceptibility of older leaves to infection. Overall, this pattern suggests that mature beds and shallow beds of eelgrass may be especially susceptible to outbreaks of wasting disease. The study highlights the importance of considering host and environmental factors when evaluating risk of disease from opportunistic pathogens.
Endangered species conservation faces well-documented funding shortfalls for recovery activities, but the listing process itself is also often hampered by limited resources at the federal, state, and provincial levels. In the United States, Canada, and other jurisdictions, the number of species proposed for listing has outpaced listing decisions, creating large backlogs of candidate species. In Washington State, the Washington Department of Fish and Wildlife (WDFW) and The SeaDoc Society (SeaDoc), a nongovernmental university-based organization, entered into a unique public–private partnership to advance the state-level listing process for the tufted puffin (Fratercula cirrhata), a candidate species since 1998. Using privately-raised funds, SeaDoc hired a visiting scientist to co-author the status report with WDFW staff. This collaboration continued through editing, revising, peer review, and the public comment period, and resulted in the tufted puffin being listed as endangered in Washington. We discuss the advantages and potential pitfalls of this joint effort, as well as the broad applicability of this model in other jurisdictions with a backlog of species awaiting endangered species listing consideration.
The Washington Department of Fish and Wildlife maintains a list of endangered, threatened, and sensitive species (Washington Administrative Codes 232-12-014 and 232-12-011, Appendix B). In 1990, the Washington Wildlife Commission adopted listing procedures developed by a group of citizens, interest groups, and state and federal agencies (Washington Administrative Code 232-12-297, Appendix B). The procedures include how species listings will be initiated, criteria for listing and delisting, public review standards, the development of recovery or management plans, and the periodic review of of listed species. The first step in the process is to develop a preliminary species status report. The report includes a review of information relevant to the species’ status in Washington and addresses factors affecting its status. The procedures then provide for a 90-day public review opportunity for interested parties to submit new scientific data relevant to the draft status report and classification recommendation. At the close of the comment period, the Department incorporates new information and prepares the final status report and listing recommendation for presentation to the Washington Fish and Wildlife Commission. The final report and recommendations are then released for public review 30 days prior to the Commission presentation. The draft status report for Tufted Puffins was reviewed by researchers and state and federal agencies. This was followed by a 90-day public comment period from September 12–December 11, 2014. All comments received were considered during the preparation of the final status report. The Department intends to present the results of this periodic status review to the Fish and Wildlife Commission for action at the February 2015 meeting.
Leatherback turtles (Dermochelys coriacea) are critically endangered, primarily threatened by the overharvesting of eggs, fisheries entanglement, and coastal development. The Pacific leatherback population has experienced a catastrophic decline over the past two decades. Leatherbacks foraging off the coast of California are part of a distinct Western Pacific breeding stock that nests on beaches in Indonesia, Papua New Guinea, and the Solomon Islands. Although it has been proposed that the rapid decline of Pacific leatherback turtles is due to increased adult mortality, little is known about the health of this population. Health assessments in leatherbacks have examined females on nesting beaches, which provides valuable biological information, but might have limited applicability to the population as a whole. During September 2005 and 2007, we conducted physical examinations on 19 foraging Pacific leatherback turtles and measured normal physiologic parameters, baseline hematologic and plasma biochemistry values, and exposure to heavy metals (cadmium, lead, and mercury), organochlorine contaminants, and domoic acid. We compared hematologic values of foraging Pacific leatherbacks with their nesting counterparts in Papua New Guinea (n=11) and with other nesting populations in the Eastern Pacific in Costa Rica (n=8) and in the Atlantic in St. Croix (n=12). This study provides the most comprehensive assessment to date of the health status of leatherbacks in the Pacific. We found significant differences in blood values between foraging and nesting leatherbacks, which suggests that health assessment studies conducted only on nesting females might not accurately represent the whole population. The establishment of baseline physiologic data and blood values for healthy foraging leatherback turtles, including males, provides valuable data for long-term health monitoring and comparative studies of this endangered population.
The extent of larval retention and natal homing in demersal fish is a topic central to the design and the efficacy of Marine Protected Areas (MPAs). Unfortunately, little is known about effective larval dispersal in many marine species. The duration of the pelagic phase in many species suggests extensive dispersal, and population genetic studies suggest large-scale exchange of migrants. On the other hand, studies on the larval distribution around oceanic islands and within estuaries, as well as mark-recapture studies indicate effective mechanisms of larval retention, in part due to local oceanographic conditions (gyres, eddies), in part because of active larval behavior such as vertical migration. However, even with limited exchange between populations, levels of gene flow are usually sufficient to homogenize allele frequencies among populations, limiting the power of traditional population genetics in estimating rates of larval retention. Here, we use genetic markers to identify the offspring of resident adult brown rockfish (Sebastes auriculatus) among incoming settling juveniles on an isolated artificial reef at Pt Heyer in Puget Sound, thus directly estimating rates of self-recruitment on the reef. The project is the first application of genetic parental identification in a marine species, and will provide valuable data for the design and management of MPAs.
Among larvae from populations of Pacific herring Clupea pallasii in Washington State, those from Cherry Point have consistently demonstrated abnormalities indicative of distress, including low weights and lengths at hatch, increased prevalences of skeletal abnormalities, and shorter survival times in food deprivation studies. The biomass of adult, prespawn Pacific herring at Cherry Point declined from 13,606 metric tons in 1973 to a record low 733 metric tons in 2000. However, correlation of larval abnormalities with adult recruitment was weak, indicating that the larval abnormalities did not directly cause the decline. Larval abnormalities originated primarily from factors independent of conditions at the spawning location because they were not reproduced by incubation of foreign zygotes along the Cherry Point shoreline but were reproduced after the development of indigenous zygotes in controlled laboratory conditions. Although the precise cause of the abnormalities was not determined, recent zoographic trends in elevated natural mortality among adult Pacific herring and resulting reduced age structures may be involved.
Populations of at least 20 asteroid species on the Northeast Pacific Coast have recently experienced an extensive outbreak of sea-star (asteroid) wasting disease (SSWD). The disease leads to behavioral changes, lesions, loss of turgor, limb autotomy, and death characterized by rapid degradation (“melting”). Here, we present evidence from experimental challenge studies and field observations that link the mass mortalities to a densovirus (Parvoviridae). Virus-sized material (i.e., <0.2 μm) from symptomatic tissues that was inoculated into asymptomatic asteroids consistently resulted in SSWD signs whereas animals receiving heat-killed (i.e., control) virus-sized inoculum remained asymptomatic. Viral metagenomic investigations revealed the sea star-associated densovirus (SSaDV) as the most likely candidate virus associated with tissues from symptomatic asteroids. Quantification of SSaDV during transmission trials indicated that progression of SSWD paralleled increased SSaDV load. In field surveys, SSaDV loads were more abundant in symptomatic than in asymptomatic asteroids. SSaDV could be detected in plankton, sediments and in nonasteroid echinoderms, providing a possible mechanism for viral spread. SSaDV was detected in museum specimens of asteroids from 1942, suggesting that it has been present on the North American Pacific Coast for at least 72 y. SSaDV is therefore the most promising candidate disease agent responsible for asteroid mass mortality.
The Asian isopod Ianiropsis serricaudis is now well established in fouling communities, often associated with introduced ascidians, throughout the Northern Hemisphere but has gone largely unnoticed because of its diminutive size (typically less than 3 mm in length) and the difficulties of identifying small peracarid crustaceans. Known locations include the northeastern Pacific (Puget Sound, San Francisco Bay, and Monterey Bay), the northwestern Atlantic (from the Gulf of Maine to Barnegat Bay, NJ), and the northeastern Atlantic (England and the Netherlands). We predict that this species is widespread along North America and European coasts, and may already be introduced to cold temperate waters of the Southern Hemisphere as well.
ABSTRACT: In 2006, a marked increase in harbor porpoise Phocoena phocoena strandings were reported in the Pacific Northwest of the USA, resulting in the declaration of an unusual mortality event (UME) for Washington and Oregon to facilitate investigation into potential causes. The UME was in place during all of 2006 and 2007, and a total of 114 porpoises stranded during this period. Responders examined 95 porpoises; of these, detailed necropsies were conducted on 75 animals. Here we review the findings related to this event and how these compared to the years immediately before and after the UME. Relatively equal numbers among sexes and age classes were represented, and mortalities were attributed to a variety of specific causes, most of which were categorized as trauma or infectious disease. Continued monitoring of strandings during 4 yr following the UME showed no decrease in occurrence. The lack of a single major cause of mortality or evidence of a significant change or event, combined with high levels of strandings over several post-UME years, demonstrated that this was not an actual mortality event but was likely the result of a combination of factors, including: (1) a growing population of harbor porpoises; (2) expansion of harbor porpoises into previously sparsely populated areas in Washington’s inland waters; and (3) a more well established stranding network that resulted in better reporting and response. This finding would not have been possible without the integrated response and investigation undertaken by the stranding network.
Master’s thesis for MS degree in Biology, Sonoma State University.
Available at http://depts.washington.edu/uwconf/2005psgb/2005proceedings/index.html
Invasive species threaten marine biodiversity on a global scale.
To test whether marine reserves provide resistance to invading species, the abundance of two conspicuous invaders, a seaweed and an oyster, were measured inside marine reserves and in comparable areas outside reserves in north-western Washington State.
Densities of both invaders were significantly higher in marine reserves than in comparable unprotected areas outside reserves. Although the causal mechanisms have not yet been identified, differential rates of human harvest do not appear to be responsible for the patterns observed.
It is provisionally suggested that physical or biological aspects of the reserves themselves may directly or indirectly facilitate biological invasion.
Recovery of severely declining resource stocks often leads to enforced quotas or reduced human access to those resources. Predators, however, do not recognize such restrictions and may be attracted to areas of increased prey abundances where human extraction is being limited. Such targeting by predators may reduce or retard the potential recovery of depressed stocks. In the San Juan Islands, northern Puget Sound, USA, marine reserves were implemented to recover depressed fish populations. We examine the role of harbor seals Phoca vitulina in the San Juan Islands food web. We describe the temporal and spatial variability in their diet, emphasizing species for which reserves were established (rockfish Sebastes spp.) and other important depressed stocks, including salmon Oncorhynchus spp. and Pacific herring Clupea pallasii. During winter and spring, seals primarily consumed Pacific herring, Pacific sand lance Ammodytes hexapterus, northern anchovy Engraulis mordax, and walleye pollock Theragra chalcogramma. During summer/fall, adult salmonids composed >50% of the diet and were particularly important in odd-numbered calendar years, when pink salmon O. gorbuscha spawn. Rockfish were not a primary prey species at any time of the year, suggesting that the abundance of alternative prey species may reduce predation pressure and provide a critical buffer to rockfish predation. The importance of considering increased visitation by marine predators to areas where potential prey are enhanced through restrictions on human extractions should be considered when modeling the efficacy of quotas and reduced access areas, such as marine reserves.
Bacterial cultures collected over 12 yr from stranded harbor seal (Phoca vitulina) pups and weanlings located in the North Puget Sound and San Juan Islands region of Washington were analyzed retrospectively to determine the most common pathogenic isolates and to describe their antimicrobial resistance patterns. Culture attempts (n = 58) from wounds, umbilici, ears, conjunctiva, nares, oral lesions, and feces yielded 134 pathogenic isolates that represented 17 genera. The majority of isolates were Gram-negative (n = 87; 65%) and of the tested isolates were most susceptible to amikacin (n = 76; 99%) and gentamicin (n = 76; 97%) and least susceptible to ampicillin (n = 76; 26%). Of the Gram-positive isolates tested (n = 29), all were susceptible to amoxicillin/clavulanic acid. The most frequent isolates were Escherichia coli(17%), β-hemolytic Streptococcus spp. (15%), Enterococcus spp. (11%), and Pseudomonas aeruginosa (11%), with all four exhibiting resistance to more than 50% of the antimicrobials tested. The variety of organisms isolated, the variation in either Gram-negative or Gram-positive predominance, and the multiple drug resistance patterns observed suggest that when treating stranded harbor seals, culture and sensitivity testing are warranted and that antibiotic therapy should be based on results.
Abstract: Fisheries for Surf Smelt Hypomesus pretiosus in the inland marine waters of Washington State are currently managed under the assumption that annual recreational harvest is roughly similar to commercial harvest. Commercial harvest is monitored by submission of mandatory fish tickets that document sales to licensed vendors. Assessment of recreational effort and harvest is complicated by (1) the lack of a licensing requirement for fishers, (2) the fact that fishing occurs throughout the year but tends to peak during locally specific time windows, and (3) the ability of anglers to engage in the fishery from private shorelines in addition to public access points (e.g., boat ramps). To adequately estimate recreational harvest, a survey method must be developed that accounts for spatiotemporally diverse harvest patterns. Here, we report the results of a pilot study that combined access-point and roving, boat-based creel survey techniques to sample a known region of high recreational fishing pressure during the traditional fishing “season” for Surf Smelt. In addition to providing a statistically valid estimate of harvest at these locations, we described patterns of both fishing effort and catch across time, in association with various environmental variables, and at public access points and private beaches. We found that based on the sitespecific estimates generated here and the number of high-use recreational fishing sites in Puget Sound, Surf Smelt harvest has the capacity to exceed the level that has been assumed for purposes of management. We conclude that combining access-point surveys and roving creel counts represents a logistically feasible and cost-effective method for estimating recreational harvest of Surf Smelt throughout Puget Sound or harvest in any other fishery with similarly complex spatiotemporal participation.
Baseline data for rockfish abundance and substrate associations were documented for newly established rockfish conservation areas (RCAs) in Howe Sound using a multilevel occupancy model, which is new to fisheries science. In 2005, a series of roaming video dives was conducted. Videotapes were scored, minute by minute, according to substrate type, revealing a strong association of rockfish with piled boulders as preferred habitat. Paired divers sighted about twice as many rockfish as were documented on videotape in the same areas (same dates). In 2006, 69 dives were conducted at 11 randomly selected RCA sites and 12 random control sites (three dives per site). Of the factors investigated, only the percentage of boulder coverage predicted rockfish abundance. In 2007–2008, side-scan sonar was deployed for locating boulder piles to streamline efficiency of dive surveys. A combination of telemetry and underwater surveys in randomly selected areas should enable unbiased, noninvasive evaluation of the effectiveness of RCAs in rebuilding populations of inshore rockfish species on the Pacific coast of Canada.
Seagrass meadows form ecologically and economically valuable coastal habitat on every continental margin except the Antarctic, but their areal extent is declining by approximately 2–5 % per year. Seagrass wasting disease is a contributing factor in these declines, with the protist Labyrinthula identified as the etiologic agent. To help elucidate the role of Labyrinthula spp. in global seagrass declines, we surveyed roughly one fourth of all seagrass species to identify Labyrinthula diversity at the strain and/or species level, combining results from culturing methods and two common nuclear DNA markers: the ITS and 18S regions of the ribosomal RNA gene complex. After assaying a subset of the resulting isolates (of which 170 were newly sequenced), we produced a cladogenic context for putative seagrasspathogenic versus non-pathogenic Labyrinthula while also defining host and geographic ranges. Assays also suggest that pathogenicity is consistently high (when present; and, even when comparing susceptibility of US East- versus West Coast Zostera marina hosts) while virulence is variable, that some isolate-host combinations have the potential for host cross-infection, and that several modes of transmission can be effective. Taken together, these data provide additional means for delimiting putative species of Labyrinthula, suggesting at least five seagrass-pathogenic and perhaps ten or more non-pathogenic marine Bspecies^, yielding a working definition for ecologists and epidemiologists attempting to reconcile the sundry data related to seagrass wasting disease.
This review was commissioned by the SeaDoc Society in light of major concern for the population trajectory of the SRKW population.
The review focuses on identifying evidence for poor body condition in the SRKW population from information presented in Seattle, March 6 2017 (see Appendix 1 Agenda). Body condition can be influenced by food availability (quantity and quality), energy balance, disease, toxin exposure, physiological status, genetics and stress from noise and vessel traffic, amongst other factors, although food availability is the most common cause in wild mammalian populations. For SRKW, food availability to individuals is determined by both prey availability and time to find, catch, share and consume prey. Anthropogenic disturbance will reduce food consumption and thus influence body condition.
The small population size and complex social structure of SRKW complicate detection of associations between measures of body condition and population dynamics. Stochastic events can skew population-wide trends substantially. Therefore, individual cases must be considered rather than analyses of trends and correlations on limited-sample-sizes. The small sample size problem hinders many analyses of this population’s ecology.
A recent shift in distribution of Northern Resident Killer Whales (NRKW) into offshore SRKW range complicates choice of a control population. NRKW could compete for space and prey, and may be influenced by environmental variables that influence SRKW. Thus when using a case control approach, and comparing parameters between SRKW and a reference population, care should be taken when using the NRKW, and another population should be used such as the southern Alaskan residents.
We explored changes in seasonal distribution and behavior of waterbirds in the Strait of Georgia, Canada, in response to increased presence of a major avian predator, the Bald Eagle (Haliaeetus leucocephalus). Eagles were widespread and their increase through fall and winter coincided with migratory movements of waterbirds. Many species of waterbird used inshore waters in early fall when eagles were scarce. Diving birds moved away from inshore waters when eagles returned in late fall and winter, whereas dabbling ducks formed large flocks in inshore waters and spent proportionally more time being vigilant as winter progressed. Flock sizes and avoidance flight distances of scoters and dabblers, but not gulls, increased with proximity to eagles. Waterbirds did not alter vigilance with distance to eagles. We discuss our findings in context of management issues regarding apparent declines and importance of understanding indirect effects of predators on prey for wildlife monitoring.
Western grebes are in decline along the western coast of the United States and often are impacted by oil spills and natural seeps when wintering along the Pacific coast. There is a dearth of information regarding the efficacy of post-oil spill rehabilitation and the evaluation of rehabilitated grebes post-release has been prevented by a lack of suitable tracking capability. This study was designed to answer several questions including: 1) can satellite transmitters be implanted successfully in Western grebes, 2) how long do the grebes survive post-release, and 3) what are their wintering and migrating patterns? Previous work resulted in a modified surgical technique to implant this species with satellite transmitters. In this next phase of the research, we used this modified technique to implant satellite transmitters in 10 Western Grebes captured in early December 2010 in San Francisco Bay, California. Nine of ten birds survived surgery and were released. Post-release, all birds survived at least 25 days suggesting a lack of complications related to surgery. After 25 days, survival showed a steady decline and currently only two grebes are still transmitting. One bird did not migrate, while the other migrated to Upper Klamath Lake in Oregon in July and recently returned to San Francisco Bay in November 2011. This is the first study to document winter site fidelity and migration of a Western grebe from its marine wintering ground to an inland breeding colony and back. It provides the first step for developing a safe technique for using intracoelomic satellite transmitters for post-oil spill tracking of Western grebes.
The main goal of this study was to gain knowledge on post-release survival and movement of Western Grebes (Aechmophorus occidentalis) using a modified technique for implanting satellite transmitters.
Sea star wasting disease devastated intertidal sea star populations from Mexico to Alaska between 2013–15, but little detail is known about its impacts to subtidal species. We assessed the impacts of sea star wasting disease in the Salish Sea, a Canadian / United States transboundary marine ecosystem, and world-wide hotspot for temperate asteroid species diversity with a high degree of endemism. We analyzed roving diver survey data for the three most common subtidal sea star species collected by trained volunteer scuba divers between 2006–15 in 5 basins and on the outer coast of Washington, as well as scientific strip transect data for 11 common subtidal asteroid taxa collected by scientific divers in the San Juan Islands during the spring/summer of 2014 and 2015. Our findings highlight differential susceptibility and impact of sea star wasting disease among asteroid species populations and lack of differences between basins or on Washington’s outer coast. Specifically, severe depletion of sunflower sea stars (Pycnopodia helianthoides) in the Salish Sea support reports of major declines in this species from California to Alaska, raising concern for the conservation of this ecologically important subtidal predator.
The recent 2000-2001 drought resulted in substantially reduced river flows that, in turn, markedly affected water properties, as shown by data collected by Washington State’s Puget Sound Ambient Monitoring Program and the Joint Effort to Monitor the Strait. A ‘densification’ was apparent in the waters throughout Puget Sound, as indicated by a reduction in the density difference between the surface and bottom of the water column. The reduction in the stratification was due to higher salinity surface waters. This observation is notable because stratification regulates numerous biological and physical processes, including the timing of the spring phytoplankton blooms, mixing and flushing. Furthermore, we observed that changes in the density gradient in the Strait of Juan de Fuca led to a marked reduction in the geostrophic exchange velocity (linked to flushing) during the drought year as compared with the higher flow year of 2001-2002. This difference has implications for larval and plankton dispersal/retention and water quality.
Cetaceans (dolphins and whales) are born into the aquatic environment and are immediately challenged by the demands of hypoxia and exercise. This should promote rapid development of the muscle biochemistry that supports diving, but previous research on two odontocete (toothed whales and dolphins) species showed protracted postnatal development for myoglobin content and buffering capacity. A minimum of 1 and 1.5 years were required for Fraser’s (Lagenodelphis hosei) and bottlenose (Tursiops truncatus) dolphins to obtain mature myoglobin contents, respectively; this corresponded to their lengthy 2 and 2.5-year calving intervals (a proxy for the dependency period of cetacean calves). To further examine the correlation between the durations for muscle maturation and maternal dependency, we measured myoglobin content and buffering capacity in the main locomotor muscle (longissimus dorsi) of harbor porpoises (Phocoena phocoena), a species with a comparatively short calving interval (1.5 years). We found that at birth, porpoises had 51 and 69 % of adult levels for myoglobin and buffering capacity, respectively, demonstrating greater muscle maturity at birth than that found previously for neonatal bottlenose dolphins (10 and 65 %, respectively). Porpoises achieved adult levels for myoglobin and buffering capacity by 9–10 months and 2–3 years postpartum, respectively. This muscle maturation occurred at an earlier age than that found previously for the dolphin species. These results support the observation that variability in the duration for muscular development is associated with disparate life history patterns across odontocetes, suggesting that the pace of muscle maturation is not solely influenced by exposure to hypoxia and exercise. Though the mechanism that drives this variability remains unknown, nonetheless, these results highlight the importance of documenting the species-specific physiological development that limits diving capabilities and ultimately defines habitat utilization patterns across age classes.
In 2006–2007, an unusually high number of harbor porpoises (Phocoena phocoena) stranded along the Washington and Oregon coastlines. Spatiotemporal analyses were used to examine their ability to detect clusters of porpoise strandings during an unusual mortality event (UME) in the Pacific Northwest using stranding location data. Strandings were evaluated as two separate populations, outer coast and inland waters. The presence of global clustering was evaluated using the Knox spatiotemporal test, and the presence of local clusters was investigated using a spatiotemporal scan statistic (space–time permutation). There was evidence of global clustering, but no local clustering, supporting the hypothesis that strandings were due to more varied etiologies instead of localized causes. Further analyses at subregional levels, and concurrently assessing environmental factors, might reveal additional geographic distribution patterns. This article describes the spatial analytical tools applied in this study and how they can help elucidate the spatiotemporal epidemiology of other UMEs and assist in determining their causes. More than one spatial analytical technique should be used if the study objective is to detect and describe clustering in time and space and to generate hypotheses regarding causation of marine mammal disease and stranding events.
In July 2013, a stranded harbor seal (Phoca vitulina) died giving birth to conjoined fetuses. The twins were joined at the abdomen and thoracolumbar spine with the vertebral axis at 180°. The cause of this unique anomaly—a first for this species—was not identified.
Vertically transmitted nematodes can be a significant case of morbidity and mortality in some pinnipeds. Examples include the transmammary transmission the infective L3 of Uncinaria lucasi in Northern fur seals (Callorhinus ursinus) and Uncinaria spp. in California sea lions (Zalophus californianus) and in Juan Fernandez fur seals (Arctocephalus philippi).
To the best of our knowledge, transmammary or transplacental transmission of nematodes has never been documented in harbor seals (Phoca vitulina). Four deceased and six live stranded harbor seal pups collected between June and August 2012 in San Juan County, Washington, were studied for evidence of vertical transmission of internal parasites. Samples evaluated included lungs, liver, and gastrointestinal tracts collected from pre-weaned pups at necropsy and fecal samples from live stranded pups in rehabilitation. Tissue samples were evaluated by rinsing through a sieve and resultant material was examined for evidence of parasites. Fecal samples were examined via centrifugal float using zinc sulfate solution. Samples from the live pups showed no evidence of parasite infestation or shedding. However, a single necropsy sample revealed a developing adult male Phocanema decipiens nematode in the gastrointestinal tract of a three-day-old male harbor seal pup, suggesting vertical transmission of this parasite can occur in harbor seals. Infestation with P. decipiens has been widely reported in adult harbor seals in the Salish Sea but this is the first known documentation of infestation in a pre-weaned pup. The prevalence of P. decipiens in pre-weaned pups should be further studied, as should the potential clinical significance of this infection in harbor seal pups.
We present a prototype monitoring strategy for estimating the density and number of occupied burrows of burrow-nesting seabirds. We use data and management questions from Washington State as an example that can be applied to burrow-nesting seabirds at single- or multi-island scales. We also demonstrate how habitat assessments can be conducted concurrently. Specifically, we compared the density and occupancy of burrows of the Rhinoceros Auklet (Cerorhinca monocerata) at nesting colonies in the California Current and the Salish Sea and in the 1970s, 1980s, and today. We estimated 36 152, 1546, and 6494 occupied burrows on Protection and Smith islands (Salish Sea), and Destruction Island (California Current), respectively. Our estimates for the Salish Sea are 52% greater than those from the 1970s and 1980s, while that for the California Current is 60% less than that of 1975. This suggests that the Salish Sea population has increased, despite greater human effects on that ecosystem. However, some of the estimated changes between the periods could be the result of methodological and analytical differences. To address these issues we recommend an unbiased and representative sampling approach (stratified random) and an approach for optimally allocating the samples among strata within and among islands, depending on the scale of the question being addressed. Optimally allocating the sample would save a great deal of field effort; using this approach, we achieve relatively high power (>0.80) to detect moderate changes (20%) sampling hundreds of fewer plots than in a sample not optimally allocated.
Presentamos un estrategia de monitoreo prototipo para estimar la densidad y el número de madrigueras ocupadas en aves marinas que anidan en madrigueras. Empleamos datos y preguntas de manejo del estado de Washington como un ejemplo que puede ser aplicado a diversas aves marinas que anidan en madrigueras a la escala de una isla única o de múltiples islas. También demostramos como las evaluaciones de hábitat pueden ser conducidas conjuntamente. Específicamente, comparamos la densidad y la ocupación de madrigueras de Cerorhinca monocerata en las colonias de anidación de la Corriente de California y del Mar de Salish en los años 70s, 80s y hoy. Estimamos 36 152, 1546 y 6494 madrigueras ocupadas en las islas Protección y Smith (Mar de Salish) y la isla Destrucción (Corriente de California), respectivamente. Nuestras estimaciones para el Mar de Salish son 52% mayores que aquellas de los años 70s y 80s, mientras que para la Corriente de California son 60% menos que la de 1975. Esto sugiere que la población del Mar de Salish ha incrementado, a pesar de los mayores efectos antrópicos en este ecosistema. Sin embargo, algunos de los cambios estimados entre los períodos podrán ser el resultado de diferencias metodológicas y analíticas. Para abordar estos temas, recomendamos un enfoque de muestreo no sesgado y representativo (estratificado al azar) y un enfoque para asignar óptimamente las muestras entre los estratos dentro y entre islas, dependiendo de la escala de la pregunta abordada. La asignación óptima de la muestra ahorraría un gran parte del esfuerzo de muestreo; usando este enfoque, alcanzamos un poder relativamente alto (>0.80) para detectar cambios moderados (20%), muestreando cientos de parcelas menos que en un muestreo no asignado de modo óptimo.
The anthropogenic input of fossil fuel carbon into the atmosphere results in increased carbon dioxide (CO2) into the oceans, a process that lowers seawater pH, decreases alkalinity and can inhibit the production of shell material. Corrosive water has recently been documented in the northeast Pacific, along with a rapid decline in seawater pH over the past decade. A lack of instrumentation prior to the 1990s means that we have no indication whether these carbon cycle changes have precedence or are a response to recent anthropogenic CO2 inputs. We analyzed stable carbon and oxygen isotopes (d13C, d18O) of decade-old California mussel shells(Mytilus californianus) in the context of an instrumental seawater record of the same length. We further compared modern shells to shells from 1000 to 1340 years BP and from the 1960s to the present and show declines in the d13C of modern shells that have no historical precedent. Our finding of decline in another shelled mollusk (limpet) and our extensive environmental data show that these d13C declines are unexplained by changes to the coastal food web, upwelling regime, or local circulation. Our observed decline in shell d13C parallels other signs of rapid changes to the nearshore carbon cycle in the Pacific, including a decline in pH that is an order of magnitude greater than predicted by an equilibrium response to rising atmospheric CO2, the presence of low pH water throughout the region, and a record of a similarly steep decline in d13C in algae in the Gulf of Alaska. These unprecedented changes and the lack of a clear causal variable underscores the need for better quantifying carbon dynamics in nearshore environments.
Abstract—As part of a current effort to restore the Salish Sea, a 16,925-km2 inland waterway shared by Washington State and British Columbia, a definitive, up-to-date list of the fishes that inhabit this marine ecosystem has been badly needed. The last such effort was published more than three decades ago. In response to this deficiency, we compiled information from various sources and identified 253 fish species observed in marine or brackish waters of the Salish Sea ecosystem, an increase of nearly 14% since the last published checklist. These 253 species, encompassing 1 myxinid, 2 petromyzontids, 18 chondrichthyans, 2 chondrosteans, and 230 teleosts, are contained within 78 families and 31 orders. This comprehensive list of the Salish Sea ichthyofauna will serve as a foundation for determining the occurrence of new species and perhaps the disappearance of others, enabling the selection of species as indicators of ecosystem health, and will provide a basis for identifying the mechanisms responsible for marine animal declines.
To migrate successfully, birds need to store adequate fat reserves to fuel each leg of the journey. Migrants acquire their fuel reserves at stopover sites; this often entails exposure to predators. Therefore, the safety attributes of sites may be as important as the feeding opportunities. Furthermore, site choice might depend on fuel load, with lean birds more willing to accept danger to obtain good feeding. Here, we evaluate the factors underlying stopover-site usage by migrant Western Sandpipers (Calidris mauri) on a landscape scale. We measured the food and danger attributes of 17 potential stopover sites in the Strait of Georgia and Puget Sound region. We used logistic regression models to test whether food, safety, or both were best able to predict usage of these sites by Western Sandpipers. Eight of the 17 sites were used by sandpipers on migration. Generally, sites that were high in food and safety were used, whereas sites that were low in food and safety were not. However, dangerous sites were used if there was ample food abundance, and sites with low food abundance were used if they were safe. The model including both food and safety best-predicted site usage by sandpipers. Furthermore, lean sandpipers used the most dangerous sites, whereas heavier birds (which do not need to risk feeding in dangerous locations) used safer sites. This study demonstrates that both food and danger attributes are considered by migrant birds when selecting stopover sites, thus both these attributes should be considered to prioritize and manage stopover sites for conservation.
Revised (2014) version is here: http://www.seadocsociety.org/publication/updated-2014-killer-whale-necropsy-protocol/
Killer whale necropsy and disease testing protocol (Updated May 15, 2014)
Killer whale strandings are rare events and biologists and veterinarians should use every stranding as an opportunity to learn more about this species. This protocol, first published in 2005 and recently updated in 2014, will provide guidelines for more comprehensive necropsies and standardize disease screening so that we might learn more about diseases of free-ranging killer whales.
Abalone abundance surveys from the 1970s were repeated 30 yrs later following a period of increased sea surface temperatures along the Pacific coast of the United States. Northern abalone, Haliotis kamtschatkana (Jonas, 1845) once abundant enough to support commercial fishing in Washington and Canada, are now extremely rare in the southern portion of their range in southern and central California. They have also declined 10 fold in northern California in the absence of human fishing pressure. In Washington, northern abalone are in decline and exhibit recruitment failure despite closure of the fishery. Flat abalone, Haliotis walallensis (Stearns, 1899) no longer occur in southern California, and in central California have declined from 32% to 8% of the total number of abalones, Haliotis spp., inside a marine reserve. The distribution of flat abalone appears to have contracted over time such that they are now only common in southern Oregon where they are subject to a new commercial fishery. Given these range reductions, the long-term persistence of flat abalone and northern abalone (locally) is a concern in light of threats from ocean warming, sea otter predation, and the flat abalone fishery in Oregon. The likelihood of future ocean warming poses challenges for abalone restoration, suggesting that improved monitoring and protection will be critical, especially in the northern portions of their distributions.
- Northern abalone (Haliotis kamtschatkana kamtschatkana) is a federally listed species of concern.
- The status of northern abalone and the characteristics of the habitats they associate with were determined showing that northern abalone have declined dramatically in Washington State with present day abundances <10% of those found in 1979.
- Northern abalone inhabited kelp beds (Nereocystis luetkeana), more than red sea urchin beds (Strongylocentrotus franciscanus) (X2 = 16, d.f. = 1, P < 0.01) or habitats with both kelp and sea urchins (X2 = 13.2, d.f. = 1, P < 0.01). Sites with Nereocystis kelp canopy had twice the percentage cover of encrusting coralline algae compared with sea urchin sites.
- No juvenile abalone (<75 mm) were found in any of the habitat types raising concerns about recruitment failure.
- Abalone co-occurred with other molluscs including limpets and scallops. Kelp holdfast microhabitats had significantly higher species richness (t = 2.2, d.f. = 6, P < 0.05), twice the effective number of species and 5x more individuals than sea urchin spine microhabitats.
- In laboratory choice experiments, juvenile abalone (20 mm) preferred coralline rocks to kelp holdfasts or sea urchin spine canopy. The small snail, Amphissa spp. (5–15 mm) was more abundant inside kelp holdfasts than under sea urchins or in rock cobble, suggesting this may be an important microhabitat.
- It is recommended that kelp beds with abundant coralline substrate be used for restoration including stocking juveniles and adult aggregations as this biogenic habitat may enhance northern abalone restoration actions.
Many productive ocean ecosystems are also highly variable, resulting in complex trophic interactions. We analyzed interannual patterns in the diet of a seabird, the common murre Uria aalge, in a region of high oceanographic productivity, the northern California Current, to investigate how these top predators adjust their chick provisioning to cope with environmental variability. Murres relied chiefly on Pacific herring Clupea harengus pallasi and surf smelt Hypomesus pretiosus to provision chicks, although they regularly returned 8 other fish taxa. Provisioning success was measured by the energy return rate to chicks, which in turn was disarticulated into energy per meal (quality) and meal delivery rate (quantity). Parents exhibited ‘compensation’ during 2 years in which smaller, low quality prey were returned more quickly than in years with normal (i.e. ‘good’) provisioning. Despite the increased delivery rate, energy return rates were still lower in ‘compensation’ vs. ‘good’ years. The lowest energy return rates occurred in 3 ‘poor’ years, during which ocean productivity was also depressed. Our results suggest that murres in this system have the ability to shift provisioning strategies to deal with some variability in prey resources, but not when limited by exceptionally poor environmental conditions.
Pacific Sand Lance (Ammodytes personatus) are energy-rich schooling fish that are thought to be important drivers of marine food webs in Alaska (USA) and British Columbia (Canada). Despite a number of studies characterizing their distribution and habitat use in Alaska and British Columbia, surprisingly little is known about population attributes in the Salish Sea. We compiled and analyzed 15,192 records collected from 1630 sites, primarily by beach seine or tow net in nearshore shallow areas between 1970 and 2009, to determine Sand Lance spatial and seasonal distribution in the inland waters of Washington State. Sand Lance were present along 78% of the shoreline that was sampled and were captured during every month of the year. The maximum number captured in individual nets increased between May and August. Fork length ranged from 1.7 to 19.0 cm and average fork length did not vary by month. The shortest minimum fork lengths were documented during April through July, likely representing annual recruits, but size at maturity is not known for the local population. Their widespread distribution throughout the region and peak abundance during summer suggests that they are an important potential prey source and could be a driver of marine food webs in this region.
Monitoring of species abundance, composition and distribution is essential for management and conservation of regional marine fish and invertebrate populations. The Reef Environmental Education Foundation’s Fish Survey Project promotes resource stewardship and helps support more rigorous scientific monitoring by enabling recreational SCUBA divers to survey for fish and invertebrate presence and abundance while diving. As volunteer survey effort increases, so does the value of these data. To solicit ideas for increasing voluntary survey efforts in the region we queried certified SCUBA divers to determine what motivated and prevented people from conducting Fish Survey Project surveys. We received 395 completed questionnaires. An interest in becoming more familiar with local species was cited as the number one reason for participation by people who had previously conducted fish and invertebrate surveys as well as for people who had never performed them but were interested. People who had never performed a SCUBA survey and were not interested in doing so indicated that their lack of confidence in identifying fish and invertebrates was the number one reason, but most indicated that free fish and invertebrate identification classes would change their mind. These data suggest that a focused advertising campaign and free fish and invertebrate identification classes are probably the best ways to solicit more recreational SCUBA divers to perform fish and invertebrate surveys in the Puget Sound Georgia Basin region.
Wild harbor seal (Phoca vitulina richardii) pups thermoregulate by hauling out of the water before they lose too much heat and expend too much energy. In rehabilitation, however, young
pups are housed in dry areas, but placed in pools for swims. Decreased caloric value of milk replacer means rehabilitated pups reach weaning and release weight slower than wild ones. Increased metabolic expenditure due to bathing also could prolong the time needed to raise pups to release size. Thermography, which measures surface temperature, is a promising method for studying thermoregulation in rehabilitating harbor seal pups. Previous studies in pinnipeds examined seasonal variation of body surface temperature, recovery after minor trauma, and locations of heat dumping over the body. We used thermography to study heat loss associated with standard seal rehabilitation bathing practices to see if bathing resulted in increased energy expenditure, potentially contributing to increasing time to release.
Rockfish comprise at least 28 of the over 200 species of fish within the Salish Sea. Because of their unique life-history, past over-exploitation, and currently degraded habitats, populations of many rockfish species in the Salish Sea have declined and some have been listed as Species of Concern by the State of Washington under the U.S. Federal Endangered Species Act and the Canadian Species at Risk Act.
The Salish Sea comprises over 6,900 square miles of habitat used by rockfish and is managed under the various jurisdictions of the Government of Canada, the United States, and the State of Washington. This workshop convened scientists, managers, and industry professionals to focus on recent and on-going research and recovery efforts of rockfish and their habitats in the Salish Sea to enable further collaboration.
The first day of the workshop included sessions detailing recent research on the historical context of rockfish depletion, benthic habitat surveys and abundance estimates, stressors, ecosystem and species interactions, juvenile recruitment, and genetics.
The second day of the workshop focused on agency, tribal, and Canadian perspectives on rockfish recovery, and included concurrent sessions designed to list additional research priorities related to reserves and population biology.
A final plenary session focused on collaborative planning and additional research needs.
A survey was distributed at the end of the workshop regarding the regional recovery priorities and the relative amount of research needed to implement each measure.
Past rockfish workshops and symposiums have focused on the establishment of reserves (Yoklavich 1998), population biology, assessments, and management (Heifetz et al. 2005), and conservation of ecological genetics and stock structure (Berntson et al. 2007) along the North Pacific.
This workshop specifically focused on rockfish in the Salish Sea because of its unique and diverse habitats, and its complex socioeconomic dynamics that influence rockfish research and recovery measures.
In the Florida Panhandle region, bottlenose dolphins (Tursiops truncatus) have been highly susceptible to large-scale unusual mortality events (UMEs) that may have been the result of exposure to blooms of the dinoflagellate Karenia brevis and its neurotoxin, brevetoxin (PbTx). Between 1999 and 2006, three bottlenose dolphin UMEs occurred in the Florida Panhandle region. The primary objective of this study was to determine if these mortality events were due to brevetoxicosis. Analysis of over 850 samples from 105 bottlenose dolphins and associated prey items were analyzed for algal toxins and have provided details on tissue distribution, pathways of trophic transfer, and spatial-temporal trends for each mortality event. In 1999/2000, 152 dolphins died following extensive K. brevis blooms and brevetoxin was detected in 52% of animals tested at concentrations up to 500 ng/g. In 2004, 105 bottlenose dolphins died in the absence of an identifiable K. brevis bloom; however, 100% of the tested animals were positive for brevetoxin at concentrations up to 29,126 ng/mL. Dolphin stomach contents frequently consisted of brevetoxin-contaminated menhaden. In addition, another potentially toxigenic algal species, Pseudo-nitzschia, was present and low levels of the neurotoxin domoic acid (DA) were detected in nearly all tested animals (89%). In 2005/2006, 90 bottlenose dolphins died that were initially coincident with high densities of K. brevis. Most (93%) of the tested animals were positive for brevetoxin at concentrations up to 2,724 ng/mL. No DA was detected in these animals despite the presence of an intense DA-producing Pseudo-nitzschia bloom. In contrast to the absence or very low levels of brevetoxins measured in live dolphins, and those stranding in the absence of a K. brevis bloom, these data, taken together with the absence of any other obvious pathology, provide strong evidence that brevetoxin was the causative agent involved in these bottlenose dolphin mortality events
ABSTRACT: Marine wildlife faces a growing number of threats across the globe, and the survival of many species and populations will be dependent on conservation action. One threat in particu- lar that has emerged over the last 4 decades is the pollution of oceanic and coastal habitats with plastic debris. The increased occurrence of plastics in marine ecosystems mirrors the increased prevalence of plastics in society, and reflects the high durability and persistence of plastics in the environment. In an effort to guide future research and assist mitigation approaches to marine con- servation, we have generated a list of 16 priority research questions based on the expert opinions of 26 researchers from around the world, whose research expertise spans several disciplines, and covers each of the world’s oceans and the taxa most at risk from plastic pollution. This paper high- lights a growing concern related to threats posed to marine wildlife from microplastics and frag- mented debris, the need for data at scales relevant to management, and the urgent need to develop interdisciplinary research and management partnerships to limit the release of plastics into the environment and curb the future impacts of plastic pollution.
Abstract: Identifying drivers of ecosystem change in large marine ecosystems is central for their effective management and conservation. This is a sizable challenge, particularly in ecosystems transcending international borders, where monitoring and conservation of long-range migratory species and their habitats are logistically and financially problematic. Here, using tools borrowed from epidemiology, we elucidated common drivers underlying species declines within a marine ecosystem, much in the way epidemiological analyses evaluate risk factors for negative health outcomes to better inform decisions. Thus, we identified ecological traits and dietary specializations associated with species declines in a community of marine predators that could be reflective of ecosystem change. To do so, we integrated count data from winter surveys collected in long- term marine bird monitoring programs conducted throughout the Salish Sea—a transboundary large marine ecosystem in North America’s Pacific Northwest. We found that decadal declines in winter counts were most prevalent among pursuit divers such as alcids (Alcidae) and grebes (Podicipedidae) that have specialized diets based on forage fish, and that wide-ranging species without local breeding colonies were more prone to these declines. Although a combination of factors is most likely driving declines of diving forage fish specialists, we propose that changes in the availability of low-trophic prey may be forcing wintering range shifts of diving birds in the Salish Sea. Such a synthesis of long-term trends in a marine predator community not only provides unique insights into the types of species that are at risk of extirpation and why, but may also inform proactive conservation measures to counteract threats — information that is paramount for species-specific and ecosystem-wide conservation.
This paper presents the findings of a collaborative project with the Tulalip Tribes Department of Natural Resources examining how tribal communities in western Washington view marine protected areas (MPAs). Using qualitative data, collected through unstructured interviews and reviews of published and unpublished literature, the study aims to improve the process of designing and managing MPAs to better serve both ecological objectives and Native American interests, by improving understanding of the socio-cultural systems that such protected areas depend upon for their long-term success. Tribal perspectives reported in the paper include the over-arching and nonnegotiable significance of treaty rights and co-management authorities; the importance of early and consistent tribal involvement in planning and implementation; the necessity of funding to insure meaningful tribal participation, especially for small tribal governments; the need for power-sharing governance structures; a desire for clear scientific justification of proposed MPAs and clear articulation of their objectives; integration of traditional environmental knowledge and tribal goals as established by the tribes rather than as assumed by others; conceptualization of tribes as part of marine ecosystems; use of MPAs as part of a broader plan to recover and protect marine habitats rather than a more limited focus on harvest pressure; and supplementing MPAs with a major environmental education program for the general public to address widespread degradation of the marine environment in the region. These findings are analyzed within a theoretical framework informed by critical historical geography and political ecology.
Small cetaceans are by-caught in salmon gillnet fisheries in British Columbia (BC) waters. In Canada, there is currently no generic calculation to identify when management action is necessary to reduce cetacean bycatch below sustainable limits. We estimated potential anthropogenic mortality limits for harbour (Phocoena phocoena) and Dall’s (Phocoenoides dalli) porpoises and Pacific white-sided dolphins (Lagenorhynchus obliquidens) using quantitative objectives from two well-established frameworks for conservation and management (the United States’ Marine Mammal Protection Act and the Agreement on the Conservation of Small Cetaceans of the Baltic and North Seas), which are similar to some management objectives developed for marine mammal stocks elsewhere in Canada. Limits were calculated as functions of (i) a minimum abundance estimate (2004–2005); (ii) maximum rate of population increase; and (iii) uncertainty factors to account for bias in abundance estimates and uncertainty in mortality estimates. Best estimates of bycatch mortality in 2004 and 2005 exceeded only the most precautionary limits and only for porpoise species. Future research priority should be given to determining small cetacean stock structure in BC and refining species-specific entanglement rates in these and other fisheries. The approach offers a quantitative framework for Canada to meet its stated objectives to maintain favourable conservation status of cetacean populations.
Species of concern are native species, sub-species or ecologically significant units that warrant special attention to ensure their conservation. The number of species of concern within the Salish Sea is used by the US Environmental Protection Agency and Environment Canada as a transboundary ecosystem indicator (called “Marine Species at Risk”). Within the Salish Sea, four jurisdictions assess which species require special efforts to ensure protection and survival of the population: the Province of British Columbia, the State of Washington, the Canadian Federal Government, and the United States Federal Government. As of December 1, 2015, there were 125 species at risk in the Salish Sea. Between 2002 (when the list was first compiled) and 2008, the number of listed species grew at an average annual rate of 1% from 60 to 64. It then made a precipitous jump to 113 listed species in 2011 (an average annual growth rate of 15% for 3 years) and has since continued to grow at an average annual rate of 2.6%. Some of the increase seen can be attributed to better understanding of the number of fish, reptile, bird and mammal species known to use the Salish Sea; however, most additions represent new listings due to concern about population declines. The number of species of concern provides a crude indicator of ecosystem health, permits cross checking of species of concern between jurisdictions, suggests where more research is needed to assess species status or causes of decline, and highlights where transboundary approaches could benefit species recovery. Assuming listing efforts have been consistent, the increasing number of species of concern within the Salish Sea over the last 13 years suggests ecosystem recovery efforts are being outpaced by ecosystem decay.
The harbor seal (Phoca vitulina) is the most commonly seen marine mammal in the Salish Sea and can be found throughout the region year round (Gaydos and Pearson, 2011). They have been intensively studied within the Salish Sea and this species profile provides an overview of what is known about them.
In the 1940s, harbor porpoise were considered one of the most frequently sighted cetaceans in Puget Sound, but by the early 1970s they had almost completely disappeared from local waters. Their numbers have since increased, but they remain a Species of Concern in the state of Washington. This in-depth profile looks at harbor porpoise in the Salish Sea, and was prepared by the SeaDoc Society for inclusion in the Encyclopedia of Puget Sound.