[env-trinity] Willow Creek Downstream Migrant Trap Site 2007 In-Season Trapping Update
Bill_Pinnix at fws.gov
Fri Apr 27 14:02:52 PDT 2007
To Whom it May Concern:
Willow Creek Downstream Migrant Trap Site
2007 In-Season Trapping Update –April 27, 2007
Synopsis: The 2007 Downstream Migrant trapping season at the Willow
Creek Trap Site (river kilometer 34) is being conducted jointly by the
USFWS Arcata Fish and Wildlife Office (AFWO) and the Yurok Tribal
Fisheries Program (YTFP) on the mainstem Trinity River near Willow
Creek, California. The site utilizes multiple eight foot diameter
rotary screw traps. The season began March 5, 2007 with the
installation of one trap. A second trap was installed March 15, 2007,
and a third trap was installed April 4th, 2007. As the river continues
to drop, salmonid catches are increasing rapidly.
This summary includes data from March 6th, 2007 through April 22nd, 2007
and is presented as raw catch. No expansions have been calculated at
Raw daily catches of Chinook salmon (Oncorhynchus tshawytscha) have been
captured each day sampling has occurred. Most Chinook salmon captured
during this time period have been young-of-the-year, and appear to be in
good condition. Weekly mean Fulton’s K values of young-of-the-year
Chinook salmon are slightly higher than 1.0 with a possible slight
increase in condition in Julian weeks 15 and 16.
Raw daily catches of steelhead (Oncorhynchus mykiss) smolts (age 1) are
increasing. Steelhead young-of-the-year showed a small pulse in Julian
Weeks 13-15. All steelhead smolts captured appear to be in good
condition with weekly mean Fulton’s K values slightly higher than 1.0.
Raw daily catches of coho salmon (Oncorhynchus kisutch) are low,
especially for natural smolts. Weekly mean Fulton’s K value of natural
coho salmon smolts are higher than 1.0, indicating good condition. All
coho salmon young-of-the-year appear to be in good condition with weekly
mean Fulton’s K values near 1.0.
We have been catching good numbers of salmonids that were marked at the
upstream Pear Tree Site, and this year may prove to have sufficient data
to get precise calculations of migration rates between the two traps.
If you have any questions regarding this summary, don't hesitate to
contact Bill Pinnix at (707) 822-7201.
(See attached file: WCT_CatchSummary_Apr_27_2007.pdf)
1655 Heindon Rd
Arcata, CA 95521
-------------- next part --------------
A non-text attachment was scrubbed...
Size: 15524 bytes
Desc: not available
Url : http://www2.dcn.org/pipermail/env-trinity/attachments/20070427/007a0def/UTF-8BV0NUX0NhdGNoU3VtbWFyeV9BcHJfMjdfMjAwNy5wZGY.pdf
More information about the env-trinity