Tag Archives: California sea lions

Seals and sea lions may be undercutting chinook and orca populations

Seals and sea lions can no longer be ignored in the effort to recover our threatened Puget Sound chinook salmon or our endangered killer whales.

A new study shows that seals and sea lions are eating about 1.4 million pounds of Puget Sound chinook each year — about nine times more than they were eating in 1970, according to the report. Please read the story I wrote for the Encyclopedia of Puget Sound, also published in an abridged version in the Kitsap Sun.

Harbor seals rest on the breakwater at Poulsbo Marina. // Photo: Meegan Reid, Kitsap Sun

Seals and sea lions in Puget Sound get the first chance to catch the chinook as they leave the streams and head out to the ocean. Since they are eaten at a very young age, these small chinook, called “smolts,” never grow into adults; they never become available for killer whales or humans.

Based on rough estimates, as many as one in five of these young fish are getting eaten on their way out of Puget Sound. If they were to survive the seals and sea lions and one factors in the remaining mortality rate, these fish could translate into an average of 162,000 adult chinook each year. That’s twice the number eaten by killer whales and roughly six times as many as caught in Puget Sound by tribal, commercial and recreational fishers combined, according to the study.

Continue reading

Navy moves ahead with plan to use guard dolphins

Navy officials have approved a plan to deploy specially trained Atlantic bottlenose dolphins and California sea lions to protect the Navy’s submarine base at Bangor.

<em>Dolphins will be used to guard the Navy's submarine base at Bangor, similar to operations at King's Bay, Ga., and other places.</em><br><small>U.S. Navy photo by Veronica Birmingham</small>
Dolphins will be used to guard the Navy's submarine base at Bangor, similar to operations at King's Bay, Ga., and other places.
U.S. Navy photo by Veronica Birmingham

Roger Natsuhara, acting assistant secretary of the Navy for installation and environment, signed the record of decision (PDF 1.7 mb) on Wednesday. Check the document for official details about the program.

Reporter Ed Friedrick wrote a story about the decision for Thursday’s Kitsap Sun. His article includes the following description of how the Navy plans to use the marine mammals.

The dolphins, accompanied by handlers in small power boats, will work at night. If they find an intruder, they’ll swim back to the boat and alert the handler, who will place a strobe light on a dolphin’s nose. It will race back and bump the intruder’s back, knocking the light off. The light will float to the surface, marking the spot. The dolphin will swim back to the boat, join the handler, and they’ll clear out as security guards speed to the strobe to subdue the intruder.

Sea lions can carry in their mouths special cuffs attached to long ropes. If they find a suspicious swimmer, they clamp the cuff around the person’s leg. The intruder can then be reeled in.

The dolphins’ sonar is better than any that man has made and they’re best for moving quickly in open water. Sea lions can see and hear better underwater and are better for shallower work around piers