Area/Topic  |  Bibliography   |  Background   |  Hypotheses   |  Home


 
 

KRIS Noyo : Chart Page

The chart on this page can not be modified, as it can in the CD version of the KRIS database. Data can be downloaded (see bottom of page).

Area Lower Noyo/Basin-wide
Topic Fish: Noyo Hatchery Coho Salmon Adult/Grilse Returns 1977-1999
 
Caption:  The graph above shows annual returns of coho salmon to the Noyo River Egg Collecting Station on the South Fork Noyo River. Adult fish are those over 56 cm (22 inches) and grilse are under this size, having spent just one year in the ocean. They are usually males and have not been included in broodstock or allowed to spawn upstream. The hatchery report attributed low returns in 1990 to low flows which were insufficient for coho to reach the hatchery. Increased returns since 1994 may be due in part to cessation of all coho harvest in the ocean. Coho populations are strongly influenced by upwelling. The poor ocean conditions in 1983 and 1998, related to El Nino, probably influenced low returns in 1983, 1998 and 1999. Adults captured in excess of egg take needs are passed upstream of the weir on the South Fork and allowed to spawn naturally. Data from annual Noyo River Egg Collecting Station reports and reported directly by Alan Grass. See InfoLinks for more information.


To learn more about this topic click here .
To view the table with the chart's data, click Chart Table web page.
To download the table with the chart's data, click hatchery77_93.dbf (size 3,293 bytes) .
To see meta information about the data table used for this topic click here
 
 
  www.krisweb.com