[env-trinity] American River Steelhead Run Up From Last Year, Still Below Good Years

[Dan Bacher]

http://www.dailykos.com/story/2016/01/11/1468470/-American-River-Steelhead-Run-Is-Up-From-Last-Year-But-Still-Below-Good-Years


American River Steelhead Run Up From Last Year, Still Below Good Years

by Dan Bacher

The number of steelhead showing now at Nimbus Fish Hatchery continues  
to be much better than last year, in spite of continuing low releases  
of 500 cfs from Nimbus Dam. If the El Nino storms continue, expect to  
see a lot more steelhead move into the river when the flows go up.

Last season hatchery workers counted only 154 steelhead trapped at the  
facility from December through mid-March.

In contrast, the hatchery has trapped a total of 320 adult steelhead  
to date. ‘”We also released two wild girls and one wild boy,” said  
Gary Novak, Nimbus Fish Hatchery manager.

“There are lots of steelhead in the hatchery now. We’re seeing about  
80 fish in the trap every Tuesday before we spawn,” stated Novak.

The hatchery has spawned 73 pairs and taken 491,717 eggs, well on the  
way to their goal of releasing 430,000 steelhead yearlings into the  
river system.

However, to put the current steelhead run in perspective, banner years  
for steelhead on the American have seen up to 2,000 adult steelhead  
counted by this time of year. During the best seasons I’ve fished for  
steelhead – 1980, 1995, 1999, 2002, 2003, 2004, 2011 and 2013 –  
anywhere from 2,000 to 4,000 steelhead have been counted at the  
hatchery.

Novak’s working theory for the much larger numbers of steelhead seen  
this year is that many of the fish didn’t come back to the river and  
stayed out in the ocean for an extra year. Most of the fish seen at  
Nimbus are three-year olds in the majority of years.

This year there appear a larger number of four-year-olds than usual,  
but we won’t know for sure until the scale samples of the fish are  
analyzed. Most of the fish this season range from 8 to 12 pounds.

The hatchery workers continue to see larger amounts of eggs per  
steelhead female, 7,000 compared to around 6,000 eggs per fish last  
year.

The hatchery last year was able to take only 192,278 eggs the entire  
season. To boost the numbers of fish they raised, they obtained  
168,838 eggs from Coleman Fish Hatchery, Novak noted.

This year CDFW staff will release 291,000 steelhead yearlings into the  
system.

American River steelhead are the largest ones found in the Central  
Valley system, due to their Eel River ancestry and excellent forage  
conditions found on the America. A fisherman tossing out a Little Cleo  
in February 2002 caught and released a wild steelhead/rainbow weighing  
24.02 pounds, the largest ever documented on the American.

  After just hundreds of the river’s native steelhead returned to  
Nimbus Fish Hatchery in the first few years after Folsom Lake was  
completed in the 1950s, the DFW introduced Eel River steelhead to the  
hatchery, boosting annual steelhead returns to the hatchery in the  
thousands every year.

Genetic analyses conducted since then indicate steelhead from both the  
hatchery and the river are genetically more similar to Eel River  
steelhead than other Central Valley steelhead stocks.

In a presentation before the Save the American River Association in  
December 2014, Dr. Ribert Titus, CDFW Senior Environmental Scientist,  
documented how steelhead in the lower American River may be the  
“fastest growing trout” in the world.

“There is a lot of food in the American – the fish average a growth  
rate of.82 mm per day. They grow really well,” he said.

He contrasted a slide of steelhead from the American River with one  
from Secret Ravine Creek, a tributary of Dry Creek. Whereas the  
American River fish is plump and healthy looking, the fish from Secret  
Ravine looks skinny and undernourished.

However, the same relatively warm conditions American River steelhead  
encounter every summer have spurred the outbreak, first documented in  
2004, of an anal vent disease called “rosy anus” according to Titus.

The American River steelhead population, along with its Chinook salmon  
run, constitutes a unique urban fishery in the shadow of the State  
Capitol that we must fight to restore and preserve. 
   
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