August
22, 2006
CRATER LAKE — I was the trout.
Or maybe a giant salamander.
This wasn’t some stream of consciousness metaphysical thing. I was
genuinely slithering upstream, partially submerged in the riffles of
chilly Sun Creek searching for bull trout.
Crater Lake National Park fisheries biologists Collin Christianson and
Stephanie Orlaineta had outfitted three of us in two layers of
undergarments, a fleece jumpsuit that fit over our clothes, then a zip-up
dry suit with a heavy nylon shell. Neoprene covered our heads and hands,
and oversized boots went over neoprene booties. We breathed through
snorkels and watched for bull trout with scuba masks. I felt like a
genetically deviant, part ninja, part Gene Simmons from the rock group
“Kiss.”
The gear is standard equipment biologists use to count populations of the
rare, elusive bull trout. Because the unschooled trout don’t congregate
in groups, when biologists want to determine fish numbers it’s necessary
to visit their underwater environment.
Bull trout is a native fish species biologists say evolved and inhabited
cold water streams like Sun Creek for more than 10,000 years, longer than
Crater Lake has existed.
Today, Klamath Basin bull trout are listed as threatened under the
Endangered Species Act. Mark Buktenica, the park’s aquatic biologist,
has coordinated the bull trout restoration program since the rare species
was discovered in 1989.
Sun Creek habitat
Sun Creek is the only remaining stream in the park with bull trout. Small
populations were once found in nearby Sevenmile, Cherry, Fourmile and
Threemile creeks and, further away, in tributaries of the Sycan River and
streams in the Gearhart Mountain Wilderness Area. In the Upper Klamath
Lake region they now only occur in Sun and Three Mile creeks. In recent
years they have gone extinct in roughly 40 percent of their historic
habitat.
In Sun Creek, bull trout used to travel up to 15 miles from the springs
near Crater Lake’s rim to Upper Klamath Lake, where they fattened
themselves on insects and tinier fish. Under ideal conditions, migrating
bull trout can grow up to 3 feet long, weigh 20 to 30 pounds and live 12
years or more. In Sun Creek, the fish are much smaller, usually only 8 to
10 inches long.
Bull trout are a subgroup of the salmon family, but they do not
necessarily die after spawning and can spawn more than once.
In recent years human activities and
non-native brook trout decimated bull trout.
“Brook trout are more aggressive than bull trout. They breed at a
younger age. And they have more eggs per female. They literally swamp out
the bull trout,” Buktenica said, noting brook males often mate with
female bull trout, which further depletes the reproductive success of bull
trout.
In Sun Creek, bull trout that once migrated up to 100 miles are now
confined to a short stretch of the river’s pristine upper reaches.
Buktenica says in 1989 Sun Creek’s bull trout populations were
perilously threatened — a fish count found only 150.
Program rebuilds numbers
So the park launched a vigorous program to rebuild those numbers. It
appears to be working. Last year’s count found 2,400 bull trout in a
fivemile section of the creek, a healthy 900 increase from a year earlier.
Bull trout
differ from brook trout because they lack markings on their dorsal fins.
Their backs are olive green with distinct pink or yellow spots, while
their bellies are light-colored.
“That’s a conservative estimate. We know there’s more than we can
see,” Buktenica said.
Measures have included electro-shocking selected portions of Sun Creek to
catch and transplant bull trout, and to capture and kill brook trout.
Brook trout targeted
Two artificial waterfalls were built to prevent brook trout from swimming
upstream to protected bull trout waters. After bull trout were removed,
biologists applied antimycin, a deadly fish toxin to kill remaining
brookies. Antimycin is an antibiotic that is harmless to mammals, birds
and most other stream inhabitants.
“We believe that without taking any action, bull trout would have gone
extinct,” Buktenica said.
I saw my first underwater trout at a likely place, a small slack water
area near a log. The others, Paula Fong, a member of the Crater Lake
Natural History Association, and Trish Door, new education coordinator for
the Crater Lake Science and Learning Center, had spied it earlier. Logs,
undercut
banks and boulders are favored fish hiding spots.
Minutes later, further upstream, I found two more. One was the stuff of
fascination. It dashed and darted, possibly boggled by, from a fish’s
point of view, the floundering whale-sized piece of fleece and neoprene
that was me, only inches away. While I parked myself in the shallow
underwater hole, the small bull trout flickered back and forth. It
periodically hid in the shadows, then quick-zipped out into the stream to
snatch food. Other times it paddled within inches of my goggles, looking
at me eye-to-eye.
“The natural condition of Sun Creek is to have bull trout,” said
Buktenica, who added the next phase of the recovery effort includes
working closely with the Oregon Department of Forestry where Sun Creek
passes through waters they manage and, critical to ongoing success,
downstream private landowners.
“We need to get migratory fish back,” he said. “Hopefully, someday
we’ll see Sun Creek open to fishing again.”
Park
fisheries biologists and volunteers help count threatened bull trout in
Sun Creek.
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