The Putah-Cache Bioregion Project:
The Curious Naturalist's Annotated Fish ListCourtesy of Peter Moyle, Ph.D, author of Fish, an Enthusiast's Guide.
The Putah-Cache bioregion contains most of the fish that inhabit central California, native and introduced. This list provides the reader with some idea of their present and former diversity in the bioregion and celebrates a few curious facts about each species.
Pacific lamprey, Lampetra tridentata, native, anadromous, scarce
Lampreys once ascended the rivers of California in such numbers that one river, the Eel, was named for them. Today their numbers have dwindled, perhaps because one of their principal prey, salmon, have also dwindled. A tiny run maintains itself in lower Putah Creek, where the worm-like larvae live for 4-7 years before transforming into predatory adults, which move out to sea. A major event in April and May, 1999, was a small run of lamprey which entertained many people with their serious business of spawning. In Cache Creek, lampreys once swam from the ocean all the way up through Clear Lake, to spawn in the tributaries.
River lamprey, Lampetra ayersi, native, anadromous, extirpated
A small (7-8 inches), predatory, and rare (in California) lamprey, the river lamprey was once observed spawning in Cache Creek. No more.
Western brook lamprey, Lampetra richardsoni, native, resident, rare
This small lamprey lives, or lived, in the tributaries where the larvae metamorphose into adults, spawn, and die. The adult never feed. They are rare or gone from the Putah and Cache watersheds, although there may be a small population in Kelsey Creek, tributary to Clear Lake.
White sturgeon, Acipenser transmontanus, native, anadromous, rare
The sturgeon, a giant relict of past fish faunas, is found today in the Toe Drain in the Yolo Bypass. The presence of scutes in the middens of Indian village sites along the creeks suggests they once ascended at least a short way up Putah and Cache creeks. At least one Putah Creek farmer in the 1920s was reputed to have fed his workers sturgeon and other fish caught in the creek.
Threadfin shad, Dorosoma petenense, introduced, resident, abundant
This small schooling fish was brought into California to provide food for bass and other game fish in reservoirs. They have done well in Berryessa Reservoir and are important food for trout, bass, and other fish, helping to sustain the fishery. They were introduced illegally into Clear Lake where they undergo wild fluctuations in population, sometimes dying by the millions when the water gets too cold. When shad are abundant, grebes and other birds congregate on the lake, eating fish like popcorn. Unfortunately, the shad deplete the lake's plankton populations, which is probably hard on native fishes such as the Clear Lake hitch.
American shad, Alosa sapidissima, introduced, anadromous, rare
The "most delicious" (sapidissima) of the shads, American shad once had small spawning runs up both Putah and Cache Creeks. No more.
Goldfish, Carassius auratus, introduced, resident, common
Wild goldfish are green to silvery in color because gold is favored by predators. The populations scattered about the watershed were derived from releases of pets, the few lucky ones that survived. People who release their pet goldfish into the wild, thinking they are setting them free, are doing the equivalent of releasing a pet cat on a freeway.
Common carp, Cyprinus carpio, introduced, resident, abundant
Carp are a superfish with whiskers, present throughout the bioregion in lakes, reservoirs, and creeks. When Monticello Dam was built, the California Department of Fish and Game attempted to poison out the entire upper Putah Creek basin in order to eradicate carp to keep them out of Berryessa Reservoir. They failed, although thousands of fish were killed. Bald eagles overwinter in the Cache Creek canyon by feeding in large part on carp washed out of Clear Lake.
Thicktail chub, Gila crassicauda, native, resident, extinct
Thicktail chub once were one of the most abundant fish in Clear Lake and the Central Valley, and a favored food of the Patwin, Pomo, and other native peoples. The last one was captured in 1957 and another species was lost forever to the world.
Sacramento pikeminnow, Ptychocheilus grandis, native, resident, common
Pikeminnows are politically correct squawfish. Big ones are fish eaters, despite the lack of teeth in their jaws; they have sharp teeth in their throats instead. Pikeminnows are still common in free-flowing streams throughout the watershed. Much abused by anglers, they are in fact both good sport when hooked and good food when properly prepared.
Hardhead, Mylopharodon conocephalus, native, resident, uncommon
Few people have encountered a hardhead because this large (to 20 inches) minnow is characteristic of deep, rock-bound pools of undisturbed foothill streams, through which it cruises in slow elegance. It is left today mainly in a few remote stretches of Putah Creek above Berryessa and in Cache Creek above Indian Valley, although a few manage to hang on in the canyon reaches of Cache Creek as well.
Hitch, Lavinia exilicauda, native, resident, uncommon
"Hitch" is an English approximation of the Pomo name for this important Native American food fish. Thousands of 12-20 inch long hitch ascended the streams flowing into Clear Lake in the spring, where they were easily captured for smoking and sun-drying. The Clear Lake hitch, distinct from the form in Putah and Cache creeks, is in decline through alteration of its spawning streams, introduction of competing species into the lake (such as threadfin shad), and random violence performed on spawning fish by some local residents. The Central Valley hitch are not doing very well either, for many of the same reasons.
California roach, Lavinia symmetricus, native, resident, locally common
Although it may not seem like it, roach is an honorable name for a minnow, the original being a common and much-loved fish in English streams. It is a remarkable fish, inhabiting some of the smallest, most remote, and warmest tributary streams. It disappears in the presence of exotic fishes, so is disappearing from many of its haunts. Still, many small streams in the region support populations, the small fish that nibble your toes when you stick them in the water to cool off.
Sacramento blackfish, Orthodon microlepidotus, native, resident, locally common
Blackfish, so-called because the tiny scales of large (2-4 lbs) adults give them a dark sheen, are one of the few native minnows that are still doing fairly well. They even support a commercial fishery in Clear Lake and elsewhere (including Nevada reservoirs into which the species has been introduced). Blackfish are easiest to see in aquaria in Chinese markets in San Francisco and Sacramento, where they are sold live as a delicacy. They survive the trip to market in crowded truck tanks because they have an incredible capacity to withstand low oxygen levels in the water.
Clear Lake splittail, Pogonichthys ciscoides, native, resident, extinct
Clear Lake splittail were once one of the most abundant fish in Clear Lake, where the young that swarmed the shores were known as silversides (ironically, since silversides may have contributed to their extinction). The last of these large minnows known from the lake were caught in the 1970s, before they were formally described as a distinct species. They probably were driven extinct by a combination of drying up of their spawning streams and introduced species preying on/competing with their young, but no one knows for sure. We should mourn the loss of the only fish species endemic to our bioregion and use its loss as a reason to take extra care in protecting its closest relative, the Sacramento splittail (already listed as a threatened species).
Sacramento splittail, Pogonichthys macrolepidotus, native, resident, rare (?)
This species used to live in the lower reaches of Putah and Cache creeks but today may still enter lower Putah Creek to spawn (we are looking for it). The Yolo Bypass, an artificial floodplain into which the two creeks flow (when allowed to) has the honor of being the principal spawning grounds of the species.
Speckled dace, Rhinichthys osculus, native, resident, uncommon
This busy little fish with a black nose-stripe is under-appreciated, perhaps because it spends its life hiding under rocks and zipping along the bottom in fast-moving streams, often at night. It is found in just a handful of small streams in the bioregion.
Red shiner, Cyprinella lutrensis, introduced, invading, abundant
This is the most invasive of the terrible trio of fish that can be legally sold as bait around California. It became legal in the 1970s despite protests that it was known to have negative effects on native fishes elsewhere. It quickly became established in huge numbers in the San Joaquin Valley and is moving northwards. It invaded lower Cache Creek in the mid-1990s and now 90% of the fish present are red shiners. It has been less successful in Putah Creek, but is becoming increasingly common. When spawning, it is a very pretty little fish, with steely blue males tinged with bright red.
Fathead minnow, Pimephales promelas, introduced, invading, common
Another bait minnow, this chubby little fish does well in the same habitats as California roach. Because anglers usually do not fish in such streams, fatheads have replaced roach in only a few areas. However, our society favors fatheads, so it is likely they will continue to spread at the expense of more desirable species.
Golden shiner, Notemigonus chrysoleucas, introduced, resident, uncommon
This seems to be the most innocuous of the three bait fishes; it is also the most widely used so is nearly ubiquitous. Yet it is rarely common in the bioregion, even though small populations seem to maintain themselves in various places. Perhaps there is a golden shiner rule waiting to be discovered.
Sacramento sucker, Catostomus occidentalis, native, resident, abundant
Suckers still thrive in Putah and Cache creeks, making their living by vacuuming insects and algae off the bottom with their fleshy, papillose lips. They are one of the earliest fishes to spawn and a big (15-24 in) female can produce thousands of eggs. One Valentine's Day I stood on the banks of Putah Creek, doing a television news interview about endangered fish, while spawning suckers splashed vigorously in the background.
White catfish, Ameierus catus, introduced, resident, abundant
White catfish, like all catfish in California, were introduced from the eastern United States. They have been extraordinarily successful, despite their large whiskery heads, because they eat anything and taste delicious. They support an important fishery in Clear Lake. They are white only when they fade because of living in murky water.
Black bullhead, Ameiurus melas, introduced, resident, common
Black bullheads are actually bright yellow. They are present but not abundant throughout the watershed, especially in ponds, where large populations of stunted fish can develop. Like other catfishes, they have barbed spines on their fins which slip very nicely into a hand or finger but do not come out so easily (personal experience; to remove a spine, soak the injured hand in saltwater).
Brown bullhead, Ameiurus nebulosus, introduced, resident, abundant
Brown bullheads are brown, more or less, but mottled on the sides. They are commonly caught with white catfish, but are less prized because their square tail makes them a bullhead, while the forked tail of a white catfish makes them a catfish.
Channel catfish, Ictalurus catus, introduced, resident, common
These sleek catfish with pointy heads and lightly spotted bodies are the catfish of supermarket fame ("Cajun catfish fillets!"). They grow to 15 or more pounds and cease being sleek, turning grossly fat, with gobbets of flesh hanging over the eyes, presumably from watching too much TV.
Chinook salmon, Oncorhynchus tshawytscha, native, anadromous, rare
Fall-run chinook salmon once ascended Putah Creek to spawn in the Berryessa Valley, as well as lower Cache Creek. They were presumably never very abundant, given the size and seasonality of the stream flows, but were neverless regular inhabitants and eaten by the Patwin and other native peoples. The return of chinook salmon to spawn successfully in lower Putah Creek in the 1990s, thanks to water provided by a series of wet years, has been one of the defining events in the creek's restoration. It would be nice to see them in Cache Creek as well.
Rainbow trout, Oncorhynchus mykiss, native and introduced, anadromous and resident, rare and abundant.
Central Valley steelhead, the sea-run variety of rainbow trout, are listed as a threatened species and a few apparently still manage to make it up lower Putah Creek every year to spawn below Putah Diversion Dam.They once ascended Putah Creek to spawn in the tributary streams above Monticello Valley and Cache Creek to spawn in the tributaries to Clear Lake. Today, in headwater streams of both watersheds, native resident rainbow trout are common, if small in size. Such fish were derived from steelhead. In reservoirs and in the reach of Putah Creek below Monticello Dam are domestic, cow-like trout from fish hatcheries, planted on a regular basis. Curiously, the below-dam reach of Putah Creek also supports a beautiful, self-sustaining resident population of fairly large trout. This population is presumably of mixed ancestry, including local natives, because after Monticello was closed, every variety of rainbow trout known to humankind was planted in the stream below it. Amazing and adaptable fish, the rainbow trout.
Brown trout, Salmo trutta, introduced, resident, uncommon
Brown trout, a native of Europe, were introduced to California on the theory that they were superior to native trout. They are a bit harder to catch, perhaps because they evolved along with modern angling, so suspicion of artifical baits is in their genes. The alternate idea, that they are smarter than the average angler, is widely rejected by the angling community. Brown trout are in a few headwater streams and are planted in Putah Creek below Monticello Dam.
Western mosquitofish, Gambusia affinis, introduced, resident, abundant
That little minnow your kid scooped up in a cup at the edge of a pond or stream is probably a mosquitofish. They look and breed like their relatives the guppies (i.e., aquatic rabbits). They are fairly effective at mosquito control in small ponds and rice fields so are reared and widely planted by the Yolo County mosquito control people.
Inland silverside, Menidia beryllina, introduced, resident, too abundant
The inland silverside was introduced into Clear Lake in 1967 to "solve" the Clear Lake gnat problem. Silversides quickly became the most abundant fish in the lake, filling the shallows with fish. They may indeed have controlled the non-biting gnat, but (surprise) did not stay in the lake. Within 20 years they had spread down Cache Creek, through the Delta and down into southern California via the aqueduct system. They have been implicated in the decline of Delta smelt, through predation on eggs and larvae. It may not be a coincidence that the Clear Lake splittail went extinct after the silversides explosion; in the early part of the century the glittering throngs of splittail in Clear Lake were ironically called "silversides."
Striped bass, Morone saxatilis, introduced, resident, uncommon
The striped bass is the scourge of the estuary but gets into the bioregion mainly by entering the lower reaches of Putah Creek on occasion.
Bigscale logperch, Percina macrolepida, introduced, resident, common
The logperch was brought into California from New Mexico by the US Air Force, with a shipment of largemouth bass for ponds at Beale Air Force Base. The ponds flooded and the perch got out, spreading throughout the Central Valley, including lower Putah Creek. They are a small, elongate bottom fish with tiger stripes.
Threespine stickleback, Gasterosteus aculeatus, native, resident, uncommon
Scientists have won the Nobel Prize for studying stickleback behavior, but these tiny red-bellied fish go largely unnoticed in our watershed. They are found mainly where there is cool, clear water with beds of aquatic plants, such as in Solano Reservoir or Cold Creek, a tributary to Clear Lake.
Sacramento tule perch, Hysterocarpus traski traski, native, resident, rare
As far as I know, these shy little (4-6 inches) fish are found in the bioregion only in a short section of Putah Creek below Putah Diversion Dam. They prefer areas with dense cover, such as trees that have fallen in the water, because the females give birth to comparatively large young and when pregnant have a hard time swimming. The males are mature a couple of months after birth and actively court small females, which can store sperm, delaying fertilization of their eggs until they are big enough to bear young.
Clear Lake tule perch, Hysterocarpus traski lagunae, native, resident, common
When Clear Lake, perhaps the oldest lake in North America, became elevated above the Central Valley, it contained tule perch, which developed into a distinctive form adapted specifically to Clear Lake. They live longer and have bigger babies than other tule perch, thanks to the productive lake environment. They are one of the few native fishes in Clear Lake that have thrived despite the savage assaults of non-native fishes, probably because they produce such big spiny young. They still require dense beds of tules for cover so one of the biggest threats to their existence is shoreline development.
Sacramento perch, Archoplites interruptus, native, resident, rare
The passing of Sacramento perch from local waters is a tragedy. It is the only sunfish native to California, a stately swimmer with iridescent purple sides set in a field of handsome vertical stripes. To the Patwin and Pomo peoples, it was an abundant and steady source of food. It has disappeared because it does not get along with its non-native relatives such as bluegill and crappie. Curiously, the only native population left in the watershed is in Clear Lake, where small numbers persist in the vicinity of Clear Lake State Park, despite the presence of numerous other sunfishes. It is not listed (yet) as an endangered species only because it has been introduced outside its native range, as a gamefish that will live in waters too alkaline to support other species.
Bluegill, Lepomis macrochirus, introduced, resident, ubiquitous
This is probably the most common and widely distributed fish in the watershed, edging out such perennial favorites as common carp, mosquitofish, and largemouth bass. Bluegill thrive in Clear Lake, Berryessa Reservoir, ponds, sloughs, and creek channels. They breed in large colonies in which big dark-colored males vigorously defend nests, embryos, and young against predators and other males. A special problem for the nesting males are small males that hang out near the nests and sneak or streak in to spawn. The sneakers and streakers join a nesting male in spawning just as he has lured a female into his nest. He then has to raise their young, as well as his own.
Redear sunfish, Lepomis microlophus, introduced, resident, common
The redear sunfish, known in the South as shellcracker because of its habit of eating snails, is deep-bodied and spiny like the bluegill but is very plain in coloration, except for a bright red "ear" on the edge of gill cover. It is especially common in Berryessa Reservoir, where it grows to respectable sizes (6-8 in) for a California sunfish.
Green sunfish, Lepomis cyanellus, introduced, resident, common
This little (usually < 4 in) sunfish is one of the most brightly colored of the sunfishes in California. Its beauty hides its aggressive and predatory nature and ability to colonize streams that otherwise support only native fishes. When green sunfish move in, the natives often do not survive the experience.
Warmouth, Lepomis gulosus, introduced, resident, rare
The introduction of this small, stout, unattractive sunfish into California is a monument to the once dominant paradigm that any fish from elsewhere was better than the native California fishes. Fortunately, it is rare in the bioregion and uncommon elsewhere.
Black crappie, Pomoxis nigromaculatus, introduced, resident, common
White crappie, Pomoxis annularis, introduced, resident, common
Politely pronounced croppee, the crappies are pleasingly symmetrical fish, with large fins. They are also very tasty and grow to respectable sizes (1-2 lb fish are possible) because they have mouths large enough to inhale small fishes, including native minnows. They prefer lakes, reservoirs, and backwaters so one of the best indicators that Putah Creek had ceased to flow during drought years was their abundance in the remaining pools.
Largemouth bass, Micropterus salmoides, introduced, resident, abundant
Wherever there is quiet, weedy, warm water in the region, there are largemouth bass cruising about in search of small fish to eat. Bass are a favorite game fish and 5-10+ pound, pot-bellied fish are encountered on occasion in the watersheds. Clear Lake is the site of tournaments in which professional and amateur bass anglers compete for big prizes, such as one of the glitter-painted high-powered sonar-equipped bass fishing boat loved by this particular brand of angler. I have no doubt that the introduction of this fish was a major factor in the demise of native fishes such as the thicktail chub and Clear Lake splittail, although there is no way to prove it except by watching bass in action. They are very effective predators.
Smallmouth bass, Micropterus dolomieui, introduced, resident, common
Prior to the construction of the Big Dams, Putah and Cache creeks were well-known among anglers for their smallmouth bass fisheries. Smallmouth bass are a stream-oriented bass in California, although they also thrive in the upper ends of reservoirs, allowing them to invade streams containing native fishes. Where they are abundant, native fishes often are not, but small populations seem to be able to co-exist with the natives, in part because the bass often focus on eating non-native crayfish rather than the native fishes.
Spotted bass, Micropterus punctulatus, introduced, resident, uncommon but spreading
I assume this fish is present in Berryessa Reservoir but don't know for sure. It is present in most other reservoirs in the state, a fairly recent arrival, spread enthusiastically by the Department of Fish and Game. It can live in streams and may be an additional threat to native fishes.
Riffle sculpin, Cottus gulosus, native, resident, common
Sculpins are cryptic (camouflaged) bottom-dwelling fishes with large heads and small, slippery bodies. When a trout angler accidentally hooks a monster 3-4 in sculpin, the distressed fisher will sometimes cut his/her line rather than touch the fish. Other anglers, however, fish with "muddler minnows" a fly tied to imitate a sculpin. Sculpins are in fact among the most fascinating of our native fishes, sitting beady-eyed among the rocks in fast water, waiting for small insects to walk past and be ambushed. The riffle sculpin is a "typical" sculpin, in that it is largely confined to cold, permanent fast-water streams usually characterized as trout waters, properly called sculpin-trout waters.
Prickly sculpin, Cottus asper, native, resident, abundant
Prickly sculpins break many of the rules of sculpindom in that they thrive not only in fast flowing streams but in warm lakes and reservoirs. They are abundant in Clear Lake, for example, hopping over the bottom and feeding on midge larvae in large numbers. Unlike many sculpins, they have free-swimming larvae, which feed on plankton for a week or so before settling down to a bottom-dwelling existence, sometimes some distance from the home nest. They are one of the few native fishes that has managed to adapt well to both altered habitats and non-native fishes.