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Photo Credit FISHBio
The
embryos hatch out after
approximately seven days and the larvae become free-swimming after another seven days. Larval fish must then move downstream to the lake quickly before the streams dry up. In the lake, larvae remain inshore and are thought to depend on stands of tules for cover until they reach approximately 50 mm and assume a pelagic lifestyle until they reach breeding age and are ready to begin the cycle again
Hitch greater than 50 mm feed almost exclusively on Daphnia, small, planktonic crustaceans. Juveniles (less than 50 mm) in the shallower, nearshore envi- ronment feed primarily on the larvae and pupae of chironomid midges, planktonic crustaceans includ- ing Bosmina and Daphnia, and (formerly) the eggs, larvae, and adults of the Clear Lake gnat (Chaoborus astictopus).
Gnat populations have been depressed by human pesticide applications to the lake and by introduced planktivorous fishes so that current Clear Lake gnat populations represent just a very small fraction of historic abundances. Hitch switch to feeding on Daph- nia after moving into the offshore limnetic habitat, although when insects are abundant they may be taken at the surface.
Studies found that stomachs of hitch caught early in the morning were empty, while fish caught in the afternoon had fed, indicating that hitch feed primarily during the daylight hours.
BACKGROUND/STATUS
Hitch once exhibited a wide distribution in the large streams within the Sierra Nevada foothills but now occur there only as scattered populations. By the early 2000s, the numbers of Clear Lake hitch seen on spawning runs had dwindled dramatically to only a few thousand fish.
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Spawning hitch are currently observed
migrating into only a few of Clear Lake’s many
tributaries and only in relatively small num-
bers. Urban and agricultural development,
habitat modification, pollution and predation
are some of the factors affecting Clear Lake
hitch populations.
Hitch spawning was known to occur in
the 1980s in Kelsey, Seigler, Adobe, Middle,
Cole, Scotts, and Manning creeks.
The major spawning streams used by
hitch in the early 1990s were, in roughly decreasing order of importance: Kelsey, Adobe, Middle, Scotts, Seigler Canyon, Cole, and Manning Creeks. Seigler Canyon Creek in Anderson Marsh Historic Park was “one of the better places to observe the still spec- tacular spawning runs” in the early 1990s.
Currently, Clear Lake hitch spawn regularly in significant, but vastly reduced numbers in only two streams in one drainage basin, in Kelsey Creek and Adobe Creek.
THE HITCH BITE
Anglers have their preferences on how to catch them (I have tried to no avail to catch a fish on a hitch pattern swimbait) – and the potential exists to have an epic day. Outside of the hitch spawning period when adult hitch congregate and largemouth bass take advantage of the easy meal – I am not aware of any quantitative studies that break down largemouth bass diet by life stage that would suggest largemouth bass specifically target and utilize hitch of any other life stage or time period to a great extent. Younger and smaller bass likely prey upon juvenile hitch when available – but it would not result in the notable bite that occurs during the spawning period.
We should all care as they are a native fish and an important part of the ecology of Clear Lake – we should however, be aware of the tendency of certain entities to demonize and attempt to use largemouth bass as a scapegoat for what is the sum of many parts, many considerably larger, but less convenient to deal with than “non-native predators.”
Until next time – tight lines.
References CCCLH 2009, Hopkirk 1974, Geary and Moyle 1980, Geary 1978, Kimsey and Fisk 1960, Lindquist et al. 1943, Moyle et al. (In Review), Moyle 2002, Moyle et al. 1995, Moyle and Nichols 1974, Murphy 1948, Richerson et al. 1994, Swift 1963.