"normal" color morph
(photo D. Casterson)

 "light" morph
(left and right; photos D. Casterson)

 Steelhead Studies in Big Creek

 return to Big Creek home page  return to Stream Studies page

Big Creek supports a healthy population of anadromous Southern Steelhead (Oncorhynchus mykiss). Most years there is a run of large adult fish entering Big Creek from the ocean to spawn, and some fish may also remain in the creek and reproduce without going out to sea ("Rainbow Trout"). Big Creek fish are protected while in the lower drainage below barrier waterfalls, except for very light fishing in the Devil's Creek Flat inholding.

The Big Sur Wildlands Project ecology class has surveyed Big Creek every summer since 1996, counting steelhead and mapping pools. They have assembled a dataset which gives a good picture of steelhead abundance during that time. One interesting finding was that numbers remained high in June 2000, the year following the Kirk Complex wildfire and associated creek runoff and sedimentation events.

Changing Color Forms (see photos above and steelhead pigmentation study) Volunteer researcher David Casterson (faculty; Soquel High School) has investigated the frequencies of "light" and "normal" color morphs in Big Creek since August, 2000. Between 2000 and 2002 a shift toward an increasing frquency of the "normal" morph was observed, both between and among year-classes. Perhaps this represents a form of directional selection during that time period.

Stream Gravels and Geomorphology UC Berkeley Professor Matt Kondolf and Postdoctoral Research Scientist Frederic Liebault have conducted a survey of creek gravels, potential steelhead spawning habitat, sediment transport and stream morphology. They plan to return in 2002 to further quantify gravel characteristics.

Populations and Genetics National Marine Fisheries Service biologist Tommy Williams has begun a survey of Big Creek steelhead, including genetics and quantitative population sampling.

Estuarine Ecology NMFS biologist Thomas Laidig is investigating the extent to which estuaries serve as rearing habitats for juvenile salmonids. Big Creek is one of five study sites for this survey.



 Juvenile steelhead in the pool near the ocean. (photos S. Clabuesch) 6-12-01

 26" adult near C9, just upstream from gauge pool. 5-2-02


 More juveniles. 6-12-01

 Research diving certification class, and steelhead photographers. Thanks! 6-12-01

 return to Big Creek home page  return to stream studies page