Chi Council for
the Clear Lake Hitch
Probable Causes for the Decline
in the Clear Lake Hitch
from 1950 to the Present
Loss of spawning habitat:
mining and channeling of major creeks in the 1950's and 60's lowered
and removed gravel spawning beds and impaired hitch access to smaller
weirs constructed to protect the footings of bridges on Kelsey,
Scotts and Middle creeks block hitch migration to about 30 miles of
historic spawning beds on those creeks.
physical barriers across streams such as low water crossings,
dams and culverts impair or obstruct hitch migration to historic spawning
in Clear Lake from non-native species:
silversides introduced into Clear Lake in the mid-1960's to combat
the Clear Lake gnat compete with hitch for the same zooplankton food
source. This fish has enormous population explosions and die-offs.
They are thought to have contributed to the ultimate extinction of
the endemic Clear Lake splittail (called chi in the Pomo language)
that occurred by the middle 1970's.
shad introduced into Clear Lake in the mid-1980's as a bait fish
compete with hitch for the same zooplankton food source. The threadfin
shad eliminate Daphnia, a principal food of hitch, from the
plankton. This fish, like the inland silverside, experiences enormous
population explosions and die-offs.
strain of largemouth bass introduced in the mid-1960's prey aggressively
on hitch, especially when hitch aggregate near the mouths of the creeks
during the spring spawning season.
Peter B. Moyle, Inland Fishes of California (2002), pgs. 136-139;
Samuel M. McGinnis, Field Guide to Freshwater Fishes of California
(2006), pgs. 208-209; personal observations of author and other Chi
Council observers. The proper use of the term "chi" to refer to the
Clear Lake splittail was explained to the author by Nelson Hopper, a
native speaking Pomo elder at Big Valley Rancheria. The Pomo word for
hitch is "hitch."
April 21, 2009
Peter F. Windrem
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