receiving approval from NOAA Fisheries in November to lethally remove sea lions
at Willamette Falls, Oregon spent little time starting the program that could
euthanize as many as 93 California sea lions this year at the Falls.
date, the Oregon Department of Fish and Wildlife has lethally removed four
California sea lions that were threatening wild winter steelhead at the Falls,
according to Dr. Shaun Clements of Oregon State University and an ODFW policy
analyst on the sea lion predation issue.
said there currently are six to seven California sea lions waiting at the base
of Willamette Falls, along with four to five of the larger steller sea lions.
One of the California sea lions was euthanized this week (Jan. 9) and three in
sea lions continue to prey on sturgeon,” he said. “The California sea lions
will be preying on winter steelhead.”
ODFW has yet to determine the amount of predation on both the steelhead and
sturgeon this year, Clements said that observers were at the Falls beginning
“Hard to predict how many we’ll capture, maybe 20-30,” he said. “But most
importantly we do expect to remove 90-plus percent of the animals that are
present during the winter steelhead run.” That run is generally November
through May each year, he added.
three California sea lions that have been lethally removed were previously
marked, according to Clements.
have to be seen at the falls at least two days to be removed,” he said. “Most
have been here for multiple years though.”
41 unclipped upper Willamette River winter steelhead, listed as threatened
under the federal Endangered Species Act, have been counted traveling over
Willamette Falls so far in January.
lions are protected under the federal Marine Mammal Protection Act, but after
trying hazing and non-lethal removal of the California sea lions for years to
discourage them from hanging out at Willamette Falls, ODFW in 2017 applied to NOAA for authorization to
lethally remove a limited number of California sea lions under a MMPA, Section
sea lions in the U.S. are not listed as endangered or threatened under the
federal Endangered Species Act. The most recent population estimate for the sea
lions in the U.S. was 296,750 animals in 2016.
applied for the permit Oct.6, 2017,
and in August 2018 NOAA convened an 18-member Willamette Falls Pinniped Task
Force that in an Oct. 15 recommendation said the permit should be authorized (see
CBB, October 26, 2018, “Willamette Falls Pinniped Task Force Recommends Lethal
Removal Of California Sea Lions,” http://www.cbbulletin.com/441726.aspx).
filed for the application because its analyses showed that the high levels of
predation by sea lions (25 percent of the steelhead run in 2017) meant there
was an almost 90 percent probability that one of the upper Willamette steelhead
runs would go extinct, according to ODFW. The level of predation on spring
chinook, although lower (7-9 percent each year), was still enough to increase
the extinction risk by 10-15 percent.
permit to lethally remove California sea lions does not apply to steller sea
lions, which are present at the Falls in growing numbers and are protected by
requested and was granted authority to remove up to one percent of the
population’s “potential biological removal” level, a metric that translates to
a maximum of 93 animals a year on the lower Willamette River.
sea lions captured by Oregon biologists are transported to a secure facility
and humanely euthanized by a veterinary staff, ODFW had previously said. Staff
will also perform a necropsy and collect samples to determine the age, health
and diet of the animal in an effort to better understand ecology and behavior
of the sea lions.
will continue to monitor sea lion predation at Willamette Falls and report its
findings to NOAA, which will decide in five years whether to renew ODFW’s
CBB, November 20, 2018, “Oregon Plan To Euthanize Sea Lions At Willamette Falls
Approved By NOAA Fisheries,” http://www.cbbulletin.com/441816.aspx
August 17, 2018, “Willamette Falls Sea Lion Task Force Meets Three Days Next
Week To Review Lethal Removal Request,” http://www.cbbulletin.com/441299.aspx
January 19, 2018, “West Coast California Sea Lion Population Has Rebounded;
Meets Marine Mammal Protection Act Goal,” http://www.cbbulletin.com/440111.aspx
August 11, 2017, “ODFW Analysis: With Continued Sea Lion Predation Willamette
Winter Steelhead At Risk Of Extinction,” http://www.cbbulletin.com/439416.aspx