At the turn of the century, horses were sometimes needed to haul 20-foot white sturgeon from Idaho's Snake River. Today, fish behemoths like that are found only in historical photo archives, although nine-foot-long lunkers are known to survive.
The story of the demise of America's
largest freshwater fish reads much like that of the Snake River's
more celebrated denizens, the chinook and sockeye salmon. Dams,
pollution, irrigation withdrawals and heavy harvests have taken a
steady toll on the bottom-dwelling sturgeon, which are thought to
live as long as a century.
In 1943, the state
banned commercial white sturgeon fishing on the Snake River, and
since 1970, sturgeon can only be caught on a catch-and-release
basis. Last year the state began requiring the use of barbless
State biologists say water withdrawals for
agriculture combined with nutrient-loaded runoff from farms, fish
hatcheries and municipalities, continue to have a major impact on
sturgeon. Bob Horton, a fish biologist with the Idaho Fish and Game
Department, says a combination of such factors turned the Brownlee
Reservoir into an oxygen-depleted stew in the summer of 1990,
killing at least 30 of the fish.
But dams remain
the biggest threat, most fish experts agree. Dams have divided a
river population into nine isolated subpopulations and kept the
wide-ranging species from its occasional forays into the Pacific
Ocean for food.
Only two of the nine sturgeon
populations - the one below Hells Canyon Dam and the one between
C.J. Strike Dam and Bliss Dam - are healthy and viable, says Tim
Cochnauer, an Idaho Fish and Game fish manager for the Clearwater
Region. "There certainly are concerns about the other populations.
There are red flags that indicate those populations are barely
holding their own."
The dams have greatly
reduced the amount of spawning habitat for the sturgeon, says
Charles Ray, Idaho Rivers United's salmon coordinator. "Over 50
percent of the river is now impounded," he says. "Sturgeon won't
spawn successfully in reservoirs, they need a free-flowing river."
By isolating different populations, the dams
have also reduced the fish's genetic variability. Cochnauer says,
"The only movement that we would expect to occur between
populations is downstream movement. That would be during high water
times of the year when fish are spilled over the dams."
Upstream movement is nonexistent because of the
dams, adds Cochnauer, even though some built around 1950 had fish
ladders. "(These ladders) were not constructed to meet the demands
of sturgeon," he says. Dams constructed later - Brownlee, Oxbow and
Hells Canyon - were built without fish ladders, he
The federal relicensing of three of the
dams may provide fish advocates with an opportunity to correct the
mistakes of the past. The Federal Energy Relicensing Commission
will consider relicensing Idaho Power's Bliss, Upper Salmon and
C.J. Strike dams in 1998, 1999 and 2000, respectively.
Conservationists say they will press FERC to force the utility to
release more water during the spring spawning
In response to the upcoming relicensing,
the company has been conducting white sturgeon studies on the
middle Snake River since 1991. The studies are looking at the
status of sturgeon populations and how the dams are affecting them,
says Ken Lepla, an Idaho Power fish biologist. The data collected
will remain proprietary information until licenses are secured, he
says, although some information is being shared with Idaho Fish and
Game and the U.S. Fish and Wildlife Service.
state is currently investigating the possibility of using hatchery
fish to enhance or supplement Snake River white sturgeon. Since
1989 an experimental program has planted marked juvenile sturgeon
on different segments on the Snake River where their growth and
survival rates are being monitored.
and Cochnauer believe that fishing had an impact on the white
sturgeon population before the dams were built. "We believe there
was probably some overharvesting of the big fish," Cochnauer said.
"There weren't very many (to begin with). They were the ones people
liked to catch and they were the ones photographed a lot."
For fishermen like Charles Ray, catching a
sturgeon is like traveling back in time. "Every time I hook one I
wonder how many times this fish saw the Pacific Ocean, or how many
times it migrated in and out of Hells Canyon before the dams were
free-lances from Portland,