Oregon,
Washington Fish, Wildlife Commissions Move to
Protect Green Sturgeon
Responding to recommendations to increase
protection for the green sturgeon in coastal
waters, the Oregon Fish and Wildlife Commission
recently voted to lower retention-size limits for
commercial fisheries that harvest this species, an
important step to ensuring a future for this
living relic.
S. Sautner/Wildlife Conservation
Society
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The Oregon Fish and Wildlife
Commission recently voted to increase
protection for the green sturgeon in
coastal waters. Like salmon, green
sturgeon spawn in rivers such as the
Rogue River, where WCS researcher Dan
Erickson attached radio transmitters
to several fish (shown above) in order
to better understand their movements.
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Newswise — Responding to recommendations to
increase protection for the green sturgeon in
coastal waters, the Oregon Fish and Wildlife
Commission recently voted to lower retention-size
limits for commercial fisheries that harvest this
species, an important step to ensuring a future
for this living relic. The Washington Commission
directed their staff to examine ways to provide
additional protection for green sturgeon.
Specifically, the Oregon commission voted to
reduce the commercial size limit for green
sturgeon from 5 feet, 6 inches to 5 feet—a move
that will protect most adult male and female
sturgeons and ensure that the maximum number of
fish reaching maturity continue to spawn. Green
sturgeon are capable of spawning numerous times
throughout their lifespan, which may exceed 60
years.
“We applaud the Oregon and Washington Commissions
for taking these progressive steps towards
protecting the green sturgeon, a resource that
represents a living link with our planet’s ancient
life,” said WCS researcher Dan Erickson, one of
the leading experts on the species.
According to the research on the green sturgeon
by the New York-based Wildlife Conservation
Society (WCS), the larger 5 feet, 6 inch-size
limit for commercial fisheries protects most
female adult fish, but leaves up to 47 percent of
the smaller-sized adult males susceptible to
harvest. Reducing the size limit to 5 feet ensures
that the most of the adult males and the genetic
diversity they represent will return to their home
rivers to spawn. The decision also brings
commercial limits into consistency with sports
fishing size limits in Oregon and Washington,
already set at 5-feet even.
Although the two remaining populations of green
sturgeon use different river systems for
reproduction (the northern spawns in the Rogue
River in Oregon and the Klamath River in
California, and the southern uses the Sacramento
river system), they frequent the same coastal
waters, an important conservation consideration
for the entire species of fish.
While commercial demand for the green sturgeon
is currently low, a number of factors have changed
during the past few decades regarding the survival
of the species. Factors such as loss of suitable
habitat, decreased water quality, and an increase
in predators, are casting doubt on the green
sturgeon’s long-term survival. Because the
population status of green sturgeon is uncertain,
efforts to reduce mortality on any front is a
positive step towards securing the future of this
species.
Besides providing data on green sturgeon
maturation rates to commissions in Oregon and
Washington State for management decisions,
Erickson pioneered the usage of radio and
satellite tags to follow the movements of
individual green sturgeon within and outside of
the Rogue River system to better understand the
ecological needs of the species.
“Relative to most other species of sturgeons,
some populations of both green and white sturgeon
are considered to be the healthiest populations in
the world,” added Erickson. “By implementing
precautionary management strategies in the face of
uncertainty, we can ensure a future for these
amazing fishes.”
Capable of growing more than seven feet long and
weighing up to 350 pounds, the green sturgeon is
one of 25 to 27 species of sturgeon worldwide,
many of which are critically endangered. Green
sturgeon are currently listed as a Species of
Concern under the US Endangered Species Act, and
the southern population of the species—which spawn
in the Sacramento River—is now proposed to be
listed as Threatened under this Act.
Other species of sturgeon—such as the beluga
sturgeon in the Caspian and Black Seas—have been
brought the brink of extinction, largely because
of the worldwide demand for their roe, commonly
known as caviar. Imports of beluga caviar have
recently been banned by the United States Fish and
Wildlife Service. The potential shift in market
pressure from sturgeon in the Caspian basin to
other sturgeon populations around the world,
including green sturgeon in North America, brings
new urgency to efforts to protect sturgeon
populations in U.S. waters from commercial
overharvest.