http://www.indybay.org/newsitems/2006/12/12/18337255.php
The Mystery of the Disappearing
Sacramento River Salmon
by Dan Bacher Dec 12th, 2006 Indy Bay
State and federal scientists, as they finish
doing salmon carcass surveys on the Sacramento,
American and Feather rivers this fall, will be
analyzing why this year's salmon returns were so
poor as compared with their pre-season ocean
abundance estimates.
In a year where salmon were supposed to be
bountiful in both the ocean and river fisheries,
this has been one of the poorest fishing seasons
on record on the Sacramento River and its
tributaries.
Rene Villanueva of Steelie Dan’s Guide Service,
like many other guides and captains on the
Sacramento, complained about the very tough
season.
“It’s the worst salmon season on the river I’ve
seen since 1970, when I began fishing the
Sacramento,” said Villanueva. “I’ve seen drought
years where the salmon came in late, in early
November, but I’ve never experienced a season like
this.”
The ocean was also strangely absent of fish, with
the exception of spurts of action from Monterey to
Fort Bragg. The only area that had any consistent
salmon fishing was off the Sonoma County coast.
This was in spite of a forecasted ocean abundance
of Central Valley stocks in 2006 of 632,482 fish,
based on a return of age-2 fish (jacks and jills)
in the fall of 2005.
Last season the Department of Fish and Game (DFG)
and Pacific Fishery Management Council (PFMC)
estimated the largest ever abundance of salmon –
1.7 million fish. However, the spawning escapement
on the Sacramento, Feather, American and Yuba
rivers, though good in fall 2005, didn’t come
close to what you would expect from the pre-season
projections.
At press time, returns to the fish hatcheries and
the rivers are significantly lower than they have
been over the past five years. For example, the
returns to the DFG’s Feather River Fish Hatchery
and Coleman National Fish Hatchery to date are
half or less of last year’s runs, while Nimbus
Fish Hatchery on the American River didn’t open
its ladder until a week later than normal.
Anglers, biologists and fish advocates have
discussed a number of theories as to why the
populations of king salmon are down this year.
Possible theories for the low numbers range from
highly unusual ocean conditions to increased Delta
pumping operations. A retired DFG captain, H.A.
Carling, is convinced that the operation of
Coleman Fish Hatchery is to blame for the low
return of fish on the main Sacramento.
In a letter to Congressman Wally Herger and copied
to the DFG Director, Carling accused the federal
government’s operation at Coleman Fish hatchery of
“decimating” “a once great” multi-million dollar
resource.
“The Coleman hatchery was constructed to mitigate
for miles of prime spawning grounds blocked when
Shasta Dam was constructed,” said Carling. “An
estimated half million adult salmon were affected.
Instead of doing this, it appears that the
management policy is to destroy a large part of
what few adults now return. Salmon counts over the
Red Bluff Diversion Dam have gone from about
30,000 fish to 4,909. Last year to date, the cont
was 10,634 salmon. What is happening?”
Carling gave an alarming account of federal
officials killing large numbers of salmon before
they spawned. “On September 30, 2005, I watched as
hundreds, if not thousands, of adult salmon were
killed, packed with ice in ‘food bank’ containers
and loaded onto two refrigerated 18 wheelers,” he
explained. “Not one salmon was spawned. These were
summer run and probably some endangered spring run
also. Who knows what else is happening at this
facility?”
He then blasted the U.S. Fish and Wildlife
Service, questioning whether they may be
intentionally trying to kill off the salmon run.
“What is the goal of the service?” he said. “Maybe
to reduce the run to such a degree that they can
shut down all salmon fishing. They did a pretty
good job in the ocean this year. Only the
Sacramento/San Joaquin River fish populations
prevented a 100 percent closure.”
Carling asked for a “full scale” investigation of
the Coleman Hatchery operation. “If they don’t
want to operate at 100 percent of capacity, which
includes transporting smolts to tidewater, then I
would suggest that you take action to transfer
operation to the California Department of Fish and
Game along with the necessary funding. This is too
valuable a resource to lose,” he stated.
Carling hand delivered the letter to Herger’s
office and mailed it to DFG Director Ryan
Broddrick, but he hasn’t heard a reply yet.
Scott Hamelberg, manager of the Coleman Fish
Hatchery, said he couldn’t “officially”
specifically respond to Carling’s letter, since
the service hadn’t received the letter from
Carling or Herger.
However, in the course of a phone interview, he
did explain his observations about this year’s
salmon run in relation to past ones and discussed
the current hatchery practices.
The number of fish returning to the hatchery has
already exceeded 65,000 and he expects the total
run to exceed 70,000 salmon. In contrast, last
year saw over 160,000 fish return to the hatchery,
a very good year for salmon returns to Battle
Creek, although many anglers reported slow
fishing.
“The low returns this year are not due to hatchery
practices,” he emphasized. “Hatchery practices
have been consistent for the past decade. We have
released 12,000 million smolts every year and have
spawned 5,000 to 10,000 brood stock.”
Regarding concerns that the fish are being killed
in alarmingly high numbers, he said that fish not
used for breeding purposes are “excessed” –
harvested – and provided to the California
Environmental Emergency Food Link. He said they
take fish from throughout the run for spawning
purposes – and “excess” the others – to provide
genetic diversity.“We don’t spawn
“We don’t spawn 5,000 fish, meeting our allotment,
and then stop spawning for the season,” he
explained. “We might spawn 100 to 200 fish then
wait for more fish to move into the facility and
then spawn them, so we are taking the fish from
different times during the run. This is proper
resource management in terms of genetic
maintenance.”
I asked him why the majority of these fish
couldn’t be put back into the creek or river for
harvest by anglers or to become part of the food
chain.
Hamelberg contended it would not be feasible as
far as limited hatchery resources are concerned.
“Then there is not telling whether these fish,
already having gone past plenty of anglers, would
be caught,” he explained.
I cited recent scientific data that indicates that
marine recycling – the process by which the
nutrients from carcasses of salmon returning from
the ocean help sustain aquatic invertebrates and
the entire river ecosystem - plays a big role in
the life cycle of the salmon.
He acknowledged the importance of marine
recycling. “The hatchery’s objective is to leave
20,000 fish in the creek so they would provide
marine recycling for the ecosystem and the
juvenile fish,” he stated.
“These salmon populations go through abundance
cycles over the years,” Hamelberg emphasized. “If
you look at the history of returns to Coleman over
a 60 year time period, you would describe this
year as an average year. Most people are looking
at narrow time span, while as a biologist I am
looking at long term trends.”
In contrast to the numbers of fish that have
already returned to Coleman this year, he noted
that in 1992 only 11,000 salmon returned to Battle
Creek and the hatchery took in 7,000 fish.
However, this downturn was explainable by the
drought from 1987 to 1991, while this year’s drop
from last year’s run is harder to explain.
Anna Kastner, manager of the Feather River Fish
Hatchery, also reported lower numbers of salmon at
the Oroville facility.
“We have received 11,383 fall run fish this year,
compared to 22,405 fish by the same date last
year,” Kastner said. “I thought that we would have
a huge run, but that’s not the case. I don’t know
what happened on the ocean or river – it’s a
mystery. Our spring run returns were good, but
it’s been a weird year; the fish did totally
different things than normal.”
The Nimbus Fish Hatchery spawned its first batch
of salmon on November 7 – and the numbers of fish
received were roughly the same as those reported
last year. “We went through about 750 adults to
spawn 46 pairs on November 8 , said Bob Burks,
manager of the Nimbus Fish Hatchery. “That’s about
half of what we spawned by the same date last
year, but last season we started spawning a week
earlier.”
“Although a few less fish have shown than we
expected, we are seeing bright fish move into the
system,” he noted. “The green fish we put back
were not even close to spawning. People were
hoping we would be buried in fish, but that’s not
what’s happening now.”
One likely reason for the low returns is unusual
ocean conditions associated with global warming
that increased salmon mortality. “Highly unusual
oceanographic conditions were observed off the
coasts of Washington, Oregon and California during
2005,” according to a Preseason Report from the
PFMC. “Upwelling conditions, which bring cold,
nutrient rich waters to the surface, did not
materialize as usual in mid April, resulting in
conditions that had not been observed in the last
50 years.”
Even more alarming, the Associated Press reported
on October 31 that a huge dead zone off the Oregon
coast this summer killed fish, crabs and sea
worms. The dead zone in 2006 “lasted nearly three
times longer than any of its predecessors before
dissipating with autumn's change in the weather,”
according to AP.
It appears that the pre-season abundance
projections by the PFMC were very wrong, based on
this season’s river and ocean fishing reports and
the returns of spawning adults this fall. It is
interesting that this year’s three-year and four
year old adults were spawned during the first two
years of the Pelagic Organism Decline in the
Delta. State and federal scientists have
pinpointed three major causes of the decline - (1)
increases and changes in water exports, (2)
toxics, including herbicides and pesticides, and
(3)exotic species.
I suggest that the dramatic Delta food chain
decline starting in 2002 may already be having a
big impact on the wild and Coleman Hatchery salmon
smolts as they move through the Delta. However,
this doesn’t explain why the Feather River
hatchery counts are down also, since the salmon
smolts are released into San Pablo Bay below the
Delta.
When the final hatchery counts and river carcass
surveys are compiled after the runs are over this
year, it will be interesting to see whether the
state and federal governments reevaluate their
methods of developing pre-season ocean salmon
abundance estimates for coming years. Being
completely wrong two years in a row doesn’t build
much confidence in their data!
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