Steller Sea Lion (eastern population)
Update: August 2012
Mojo's tag has stopped transmitting. It was last heard from when Mojo was just north of Sitka, Alaska. The sensor histograms show that Mojo was still actively diving and hauling out around the time the tag failed. It's unclear whether the tag dropped off when he molted or some other fate befell him.
Video by Robin Lindsey
On February 16, 2012 the Washington Department of Fish and Wildlife Marine Mammal Investigations responded to a six-month-old Steller sea lion pup stranded at Pacific Beach, Washington. They collected the emaciated pup and transferred it to Wolf Hollow Rehabilitation Center on San Juan Island for stabilization, treatment, and care. Staff members named the pup “Mojo”. He responded well to rehabilitation and more than doubled his weight. On May 29, 2012 he was released wearing a temporary satellite transmitter designed to track his movements post-release.
This is project of NOAA’s Northwest Marine Mammal Stranding Network, which responds to stranded marine mammals in Washington and Oregon. The stranding response, rehabilitation and post-release monitoring was made possible, in large part, through the John H. Prescott Marine Mammal Rescue Assistance Grant Program. Collaborating network groups that made this project possible include the Washington Department of Fish and Wildlife Marine Mammal Investigations, Wolf Hollow Rehabilitation Center, SeaDoc Society, and NOAA's Protected Resources Division.
The stranding response, rehabilitation and post-release monitoring was made possible, in large part, through the John H. Prescott Marine Mammal Rescue Assistance Grant Program. In-kind contributions also were provided by Wolf Hollow Wildlife Rehabilitation Center, the SeaDoc Society, and the Washington Department of Fish and Wildlife.
A new paper just released in the Journal of Marine Mammalogy shows that Steller Sea Lion predation on Harbor Seals in Glacier Bay, AK could be responsible for the decline in Harbor Seals in that region.
While there is no evidence that Stellers are predating harbor seals in the Salish Sea region, it will be interesting to watch for this type of activity in the future.
In the Salish Sea, our Harbor Seal population is at carrying capacity and we are seeing more and more Steller Sea Lions in the region in the fall, winter and spring.
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.
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.
This is a transcript of a talk by Joe Gaydos.
Well the first reason we need marine fish and wildlife research is that scientific information excites us and makes us care; it gives us the information we need to get people excited about marine conservation.
Americans love naming. Maybe it goes back to Adam’s task of naming the animals. Anyway, we feel that if you can name an animal, you know it. But is that really true?
You recognize and can name a harbor seal, but how deep does it dive? How many do we have in San Juan County? What percentage of the harbor seals are estimated to be hauled out at any one time on a very low tide in the summer time? How long can they live? Why has the population rebounded?
Harbor seals can dive to 600 feet with no trouble; then can utilize every foot of our Salish Sea marine ecosystem. We have about 7,000 in San Juan County. We know this because Washington State Fish and Wildlife does aerial surveys in the summer time when we know that about 60% of the seals are hauled out at any one time. Multiply the number counted by a correction factor of 1.6 and you have an estimate for the number of seals. The oldest reported harbor seal was 34 years old. The population has rebounded because of the enactment and enforcement of the Marine Mammal Protection Act. Facts like these make an animal much more interesting than its name alone!
It is the same thing with the Southern Resident Killer whales. Why do we care about saving killer whales?
The first reason is because we are emotionally tied to them. We care because they are a matrilineal society with pod leaders that can live to be 90 years old. A female transient killer whale’s first born son will stay with her for her entire life; that makes us care.
The second reason we care about saving killer whales is because our health is intimately tied to their health and the health of the ecosystem. Southern resident killer whales have some of the highest levels of contaminants in their blubber of any marine mammal in the world. What do they eat? Salmon. How many of us eat salmon? Does that give you cause for concern? It should.
Two porpoise species that frequent the Salish Sea provide us with another good example of how human health and well being is intimately tied to the health and well being of fish and wildlife. By studying wildlife and wildlife health, we can learn more about human health. Have you have heard about Cryptococcus gatii, the fungus that is killing people in Washington and BC? This fungus also has killed about 25 porpoise in the region and disease in porpoise has acted as an early warning for human and domestic animal health. We had dead porpoise in Washington before we this disease was killing people or cats.
The third reason we care about healthy fish and wildlife populations is economics. These Steller’s sea lions frequently seen in the Salish Sea during the winter each weigh about 2,000 pounds. How much salmon do you think one Steller sea lion can eat? What is the impact on endangered salmon stocks? What is the economic tradeoff between having sea lions for ecotourism and having salmon for fishing? I tell you: both salmon and Steller sea lions are important. The importance of salmon is obvious. What about of Steller’s Sea lions? People talk about whale watching, but let’s just talk about watchable wildlife in general rather than focusing on one species. In 2001, over 47% of Washington’s residents participated in wildlife watching. In doing so, Washington residents spent $979 million resulting in a total economic output of $1.78 billion, generating and or maintaining 22,000 jobs. Guess where most wildlife watching occurs” In Washington’s Rural Counties like San Juan County.
Let’s go from a 2,000 pound Steller sea lion, which by the way is larger than a grizzly bear, down to an invertebrate that lives of microscopic plankton. Let’s talk anemones. Let’s talk any of the over 3000 invertebrates we have in the region; take the white-lined dirona, which is just a type of sea slug. It is a beautiful sea slug and it is creatures like these that bring people from all over the world to San Juan County to SCUBA dive. The Washington SCUBA alliance reports that more than 15,000 divers are certified to dive here in the Pacific Northwest yearly.
That’s right, despite the cold water the world’s best known underwater explorer and original SeaDoc Jacques Cousteau rated diving in the Puget Sound as second in the world only to the red sea! More than 1,000 dive related businesses exist in the state.
Let’s move up the food chain a bit. We have over 225 species of fish in the region. In the 1970’s lingcod populations in Puget Sound proper were low, prompting an almost complete moratorium on fishing from 1978 to 1982. The same thing happened in the San Juans in the 80s and 90’s. Good science let us know what was happening with the population and good science gave us a simple solution to solve the problem. Shorten the season. A nine-month fishery with a daily bag limit of 2 was restricted to a 6-week fishery with a daily bag limit of 1. Since 2000, ling cod fishing has substantially improved in the San Juans. This is an example of economics and human health and well being; the ability to harvest local nutritious food. And just like with marine mammals, fish research allows us to learn how cool fish are.
Take a tiger rockfish. We have over 26 species of Rockfish in the Puget Sound area. Science gives us information that excites us about these fish. They are all members of the Scorpionfish family and have poisonous spines. Did you know that? Some are schooling, some are loners, some move, some stay on the same rock their entire adult life. Even if you capture them, take them up into a boat and move them several miles away and release them, they’ll be back at that same rock in a day or two.
Science also is helping us to recover rockfish. When salmon stocks went down in the 1980’s people thought, hey, we can get these people to fish rockfish – hence the big spike in harvest in 1987 and 1989. Only, there was a little problem. We thought rockfish might live 30 years. Some species like the yellow-eye actually can live 118 years!
You see, there is a reason for good science beyond interest, it is called economics.
This is a red- urchin. How old do you think it can live? In Washington State we harvest about 475,000 pounds or about ½ million dollars worth of red urchins annually. I think it is important that we know how long they can live so we can design harvest strategies to sustain the fishery for eternity. Red urchins, by the way, can live to be over 100 years old.
And don’t think I’ve forgotten birds. I have not. We have about 160 species of birds that depend on our marine environment and they embody everything I’ve told you today about why we need research. Take surf scoters as an example. Because the population has declined 50% over the last 25 years we needed to figure out where they went when they were not in Puget Sound. We implanted satellite transmitters and watched these bird - Wow - fly all the way to the Northwest Territories and Ninavut to breed, then back to Puget Sound; maybe some went down to Humboldt Bay to molt and then back here again! The satellite track on one animals shows it flew to the Northwest Territories, across the Beaufort Sea to Alaska then back down to BC and then Washington. Amazing!
Science will amaze you and increase your respect for and appreciation of wildlife. Science also tells us about diseases that birds can carry that can impact human health –diseases like HPAI H5N1, Salmonella, and others. And of course, there is economics of bird recovery and having sustainable populations of wild birds. Bird watching is one of the most popular wildlife viewing activities for Washingtonians, who have the fourth-highest participation rating in the country. Did you realize that 36% of Washington residents regularly participate in bird watching activities? As a side note, only 16% fish recreationally.
So when you see or think about amazing fish and wildlife, think about how much science has helped us. It helps use appreciate how magnificent they are; It helps us understand how their health and the health of the ecosystem is intimately linked to our health; and it helps us economically, whether it was through harvest or through tourism and watchable wildlife.