1. HAZING STARTS FOR
FISH-GOBBLING SEA LIONS IN COLUMBIA RIVER
March 02, 2007 Fish and Wildlife Columbia
The bullets -- in this case rubber -- began flying
Thursday in what is the earliest and most
ambitious attempt to disturb the eating habits of
California and stellar sea lions in the area below
the Columbia River's Bonneville Dam.
"This is going to be more intense that last year,"
the U.S. Army Corps of Engineers' Bernard Klatte
told the Technical Management Team Wednesday. The
multi-entity "hazing" effort below Bonneville
began Thursday and will continue through the end
of May, seven days a week during the daylight
"This is considered a maximum effort where we'll
likely be hazing from dawn to dusk" throughout the
spring chinook salmon migration, and sea lion
residency, in the river, according to Robert
Stansell, the Corps' leader for research at the
dam that has for the past six years evaluated sea
lion predation's impact on the salmon runs. Two of
the upriver stocks, Upper Columbia spring and
Snake River spring/summer chinook, are listed
under the Endangered Act.
Those impacts have been judged severe enough that
states of Idaho, Oregon and Washington late last
year applied to the federal government for
permission to lethally remove some of the
California sea lions, which are protected under
the Marine Mammal Protection Act. The stellar sea
lions are ESA listed.
But even if permission is gained, it is not likely
to come within the next two or three years. So
efforts to make the pinnipeds uneasy and/or chase
them away will be stepped up this year. The sea
lions have for the past several years gathered at
the base of the dam in springtime to feast on
spawning chinook salmon that come looking for fish
ladders to continue their journey.
Historically few of the marine mammals swam the
140 miles upstream. But, coincident with the new
millenium's increase in salmon numbers, more and
more pinnipeds have found their way to the dam
each year. They are also arriving earlier, and
staying longer as years go by.
The Corps researchers estimate that the sea lions'
predation on salmon has also increased, from 0.35
percent of the total upriver spring chinook run in
2001 (1,010 salmonids) to 3.4 percent or 2,920
salmon in 2005. Last year the lions consumed an
estimated 2.8 percent of the upriver run in the
area immediately below the dam.
Observers this year noted the presence of both sea
lion species at the dam in mid-January. The
stellars have appeared that early before, but it
is by far the earliest California sea lion
arrival, Stansell said. In 2002, the first
California sea lion sighting was later in March
and each year that date has slid back farther on
the calendar. Last year the first was seen in
"They're eating steelhead so far," as well as
lamprey, Stansell said of the California sea
lions. The upriver spring chinook run has not yet
begun to flow with only one counted passing
Bonneville to-date. The first chinook taking by
the pinnipeds was witnessed Monday, a day in which
seven stellar and seven California sea lions were
sighted at the dam. In past years as many as 100
individual California sea lions have made their
way upriver eventually. The spring chinook run
normally peaks in late April.
The large stellar sea lions last year focused on
white sturgeon. They were observed killing 276 of
the big fish in the area immediately below the
This year already the stellar sea lions have been
seen taking "over 300 sturgeon" of all sizes in
the dam's tailrace, Stansell said. He said he did
not expect that number to swell greatly. Last
year, as soon as the hazing began the shyer
stellar sea lions left the area, while the
recalcitrant California pinnipeds were little
"I think we're going to see a reduction" in
predation on white sturgeon immediately below the
dam, Stansell said, with the stellars moving
downstream. Some hazing of the big creatures will
likely continue downstream, where fishery
officials are on the river conducting white
State officials are very concerned about the
potential effects of sea lion predation on white
sturgeon, according to Charlie Corrarino, the ODFW
Conservation and Recovery Program manager. Many of
the stellar targets are mature females, 30 years
old or older. So they are not quickly replaced.
"They're often eating the cream of the crop," he
In 2005 a first hazing effort was launched but
spanned only four days. Last year, efforts were
increased in an attempt to evaluate hazing's
effects on the pinnipeds' behavior. The evaluation
was carried out in four-day blocks -- two days
with hazing and two days without -- from March 5
through May 27 with a total of 42 days of hazing.
Verbal and physical hazing, rubber bullets and
buckshot, cracker shells, seal bombs, and other
tactics were used from the dam itself and from
boats downstream of the boat restricted zone
immediately below the dam. Acoustic deterrence
devices were also used.
A task force that will be formed to recommend
whether or not the state should get permission to
lethally remove individual sea lions will review
what tactics have been used in the past to deter
the sea lions, Corrarino said.
It will ask "what have the states done already?"
Corrarino said. So the maximum hazing effort will
employ all legal means to disrupt the plundering
of chinook and sturgeon.
The results showed that the hazing made little
difference in the California sea lions' salmon
consumption. Most that were stirred by the hazing
returned almost immediately.
So the effort will be intensified. U.S. Department
of Agriculture Wildlife Services agents will work
from the dams, and the Oregon and Washington fish
and wildlife agencies and state police and
Columbia River Inter-Tribal Fish Commission
biologists, and others, will work from boats for
about 10 miles downstream. They will this year be
allowed to haze in the boat restricted zone for
the first time. The sea lions last year found safe
haven in the zone, only to quickly return to the
dam when the hazers backs were turned.
Corrarino said that the law also allows the use of
non lethal deterrents by certain groups of people
(sport anglers, commercial fishermen, marina
operators, etc.) in specific situations. Private
individuals can deter marine mammals from damaging
private property, including fishing gear and
catch, so long as the methods used do not result
in the death or serious injury of an animal.
NOAA Fisheries, charged by the MMPA with
protecting the pinnipeds, last May issued a draft
list of legal hazing methods for California sea
lions and Pacific harbor seals. That list can be
found at http://www.nwr.noaa.gov/Marine-Mammals/Seals-and-Sea-Lions/Deterring-Pinnipeds.cfm
Any hazing must be consistent with local
ordinances, Corrarino said. Seal bombs and cracker
shells, as an example, may require a permit. And,
it may be illegal to discharge a firearm in
Fishermen can only use the non-lethal deterrents
when actively fishing with gear in the water.
Fishermen must be able to distinguish among the
different species of marine mammals because the
deterrents are for Pacific harbor seals and
California sea lions, not Steller sea lions which
are ESA listed.
Sea Lion Exclusion Devices – huge grates that
allow fish passage but don't allow the pinnipeds
in – have already been installed at nearly all of
the dam's 12 fish ladder entrances, Stansell said.
The SLEDS were built and first installed last year
the sea lions were seen climbing all the way up