Animals
Net Gains: The Economics of Removing Derelict Fishing Gear
One of the best examples of science coming to the rescue of a dollar-and-cents conservation issue occurred when the SeaDoc Society recently got caught up in the question of abandoned fishing nets. In partnership with the Northwest Straits Initiative, SeaDoc developed a predictive model that clearly shows the cost of these ghost nets that continue to trap and kill marine life for decades.
Northwest Straits Initiative-funded researchers made multiple dives on derelict nets, counting trapped critters, studying decomposition rates, and determining how much of the dead marine life fell out of the nets as they were recovered (Over 17% of the catch never made it to the surface, showing how critical it is to have underwater scientists on the job). SeaDoc then dove into the data, actually inventing a statistical model to predict each cast-off net’s killing capacity.
The results? Abandoned nets catch and kill more than 1,000 invertebrates (mainly crabs), 150 fish, and nearly 80 birds every year, year after year after year – and most of these silent killers have been doing their dirty work since the 1970s. Run that data through the seafood value calculator and it quickly adds up, with each net wasting $19,656 in Dungeness crab alone, every 10 years. The one-time cost to retrieve a derelict net? $1,358. It doesn’t take an accountant to do that cost-benefit analysis.
Only through funding from private donors like you was SeaDoc able to do this ground-breaking (and net-cutting) science, which has led to clear policy and, more importantly, vital and measurable improvement in the Salish Sea ecosystem. Thank you.
To view the manuscript just published in Marine Pollution Bulletin, click here (pdf).
For more about SeaDoc's derelict fishing gear project, see our lost fishing gear page.
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Eulachon
The eulachon (Thaleichthys pacificus) is an important food source for many marine fish, birds and mammals throughout the Salish Sea. Historically it has been an important food source for many Native American tribes.
In March of 2010 the NOAA announced it will list the eulachon as Threatened under the US Endangered Species Act. This fish is also called the candlefish because it is packed with so many calories you can light a dried one like a candle.
For more information about the listing, download this pdf from NOAA, this question and answer pdf on the decision to list as Threatened, or visit the Eulachon page at the northwest office of NOAA Fisheries.
For another take, visit http://qmackie.wordpress.com/2010/03/31/vanishing-eulachon/.
Read about other species of concern in the Salish Sea.
We'd hoped to find a video of someone lighting a eulachon on fire, but couldn't...
(Photo shows an Alaskan eulachon. Photo by David Beatley, US Forest Service.)
Killer Whale (Orcinus orca)
Overview
Three distinct types of killer whales, often called orcas because of their Latin name, Orcinus orca, can be found in the Salish Sea.
People are most familiar with the fish eating ecotype or “resident” orcas. These whales are salmon eaters, preferring Chinook as shown in recent studies.
In the Salish Sea there are two resident groups, the Southern Resident community (made up of 3 pods; J, K, and L) and the Northern Resident Community (made up of 16 pods; A1, A4, A5, B1, C1, D1, H1, I1, I2, I11, I18, I31, G1, G12, R1 and W1).
Less commonly seen are the marine mammal eating ecotype or “transient” killer whales. While the fish eating residents hunt in large groups, the mammal-eating type of killer whales are usually seen in small groups of 3-5 animals.
Occasionally, “offshore” ecotype killer whales are spotted in the Salish Sea. These slightly smaller animals are thought to be fish eaters like the residents.
Orcas can be identified by the shape of their dorsal fin and white saddle patch and are individually known by name to experienced whale watchers.
Status
All ecotypes of killer whales are listed as Endangered in Washington State.
The US Federal Government lists the Southern Residents as endangered and the Canadian Federal government lists Offshore killer whales as a species of concern, the Northern Resident and Transient populations as threatened and the Southern residents as Endangered.
Toxins and Disease
Killer whales from the Salish Sea are some of the most contaminated marine mammals in the world and toxin loads are considered a factor in causing the decline of the southern resident population. Disease too is a major threat to the long term health of killer whale populations.
Oil Spills
Oil spills have been called one of the greatest threats to the long term survival of the southern resident killer whales.
To address this concern, the SeaDoc Society gathered a group of almost 40 scientists to develop a plan for keeping killer whales out of an oil spill.
To see notes from that meeting see: (attached)
To read about how the Exxon Valdez is thought to have impacted resident and transient killer whales in Alaska, see (attached)
More Information
Below this line are all the content items in the SeaDoc site that have been tagged with the term Killer Whale.
Elephant Seals
Elephant seals are by far the largest of the different seals and sea lions found in Salish Sea. Adult males can be 15 feet long and weigh 5,000 pounds. These seals mate and give birth on beaches and islands off the coast of California and Mexico. Males make long distance migrations to southern Alaska and the Aleutian Islands and back twice a year while females tend to migrate west and have been sighted as far as Midway Atoll in the Northwest Hawaiian Islands. While they forage off the continental shelf where they make dives almost a mile deep, some elephant seals do come into the inland waters surrounding the San Juan Islands to haul out to rest. Elephant seals hold their breath for long periods of time even while resting on land. This regularly fools people into thinking they are dead. In the summer, large male elephant seals can be seen around the San Juan Islands, inspiring some and baffling others.
Multi-year harbor seal research
Three times each summer the SeaDoc Society and Cascadia Research visit Smith Island to survey the harbor seal population. Smith Island is part of the
San Juan Islands National Wildlife Refuge and is closed to the public. The visit consists of a count of live animals followed by a count of all carcasses. Scientists also try to count placentas to track birth numbers.
According to Sara Heidelberger, the third year veterinary student who necropsied this animal, this female seal was in good condition with a thick layer of blubber. Her teeth were deeply and evenly worn, suggesting she was relatively old. She had recently given birth. The team collected the skull for further study. Photo taken July 23, 2010.
Warning: Shellfish Closure in some Washington State Counties
Shellfish harvesting has been closed in numerous Washington counties due to the presence of the marine biotoxin Alexandrium, which causes Paralytic Shellfish Poisoning (PSP). Harvesting is closed whenever naturally occurring harmful biotoxins are detected. Once called "red tides," blooms of naturally occurring biotoxins are now more commonly referred to as Harmful Algal Blooms as there are some red algal blooms that are not harmful. Naturally occurring biotoxins like PSP are not destroyed by cooking or freezing. Please check the Washington State Department of Health for more information and each time before you harvest shellfish: http://ww4.doh.wa.gov/gis/mogifs/biotoxin.htm
Also see: http://www.seattlepi.com/local/422060_tide19.html
Courtesy of SeaDoc intern Sara Heidelberger.
The Mystery of Surplus Predation
In the Salish Sea, some transient killer whales seem to be killing sea lions for no particular reason. Joe Gaydos provided background for a Kitsap Sun piece by Christopher Dunagan discussing the four sea lions apparently killed by blunt trauma from orcas in a single month.
A 2005 publication by Gaydos discussed five harbor seal pups found decapitated by killer whales, but not eaten.
The article discusses possible causes of this "surplus predation" and reinforces the importance of quick reporting of stranded and dead marine mammals, because the faster the animals can be recovered, the more we can learn from them.
Kitsap Sun: http://pugetsoundblogs.com/waterways/2010/05/14/transient-orcas-may-be-l...
Photo: Stranding Network volunteer Maria Webster standing by one of the dead Steller sea lions on North Beach of Orcas just before SeaDoc necropsied it. Credit: Joe Gaydos.
New Comments on Rockfish Conservation
Independent of the recent Federal listing of 3 rockfish species, Washington State is working on their rockfish recovery plan. Today SeaDoc submitted comments on the revised draft Environmental Impact Statement.
While most of the recovery plan is good, the State is still proposing that hatchery production and the use of artificial habitat be used as part of the recovery strategy. SeaDoc feels that hatcheries and artifical habitat are not good ideas.
PDFs:
Read the WDFW draft rockfish EIS
Comments must be received by 5pm on May 21, 2010. Visit the Washington Dept of Fish and Wildlife for more information.
Rockfish Listed by NOAA Fisheries
http://www.seadocsociety.org/files/pdfs/GB-PS_Species_of_Concern_2008%20Manuscript.pdf
Also see:
http://seattletimes.nwsource.com/html/localnews/2011714303_rockfish28m.html
Garbage in stomach of dead gray whale on West Seattle beach
The Seattle Times reports that a gray whale that died after stranding on a beach in West Seattle had quite a bit of garbage in its stomach. Biologists with the Cascadia Research Collective surveyed the contents of the stomach and found sweatpants, a golf ball, more than 20 plastic bags, surgical gloves, and duct tape.
Read the full article, published 4/19/2010, at http://seattletimes.nwsource.com/html/localnews/2011649749_whale20.html