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Bibliography on Fish of the Salton Sea


Barlow, G.W. 1958. Daily movements of desert pupfish, Cyprinodon macularius, in shore pools of the Salton Sea, California. Ecology 39: 580-587.
NOTES: Shallow pools are a regular feature of the shoreline of the Salton Sea. The desert pupfish is abundant in these pools. The temperature of the water of the pools changes rapidly. The shallow water heats and cools faster than the deep water. For a short period during each morning and each evening the pools are rather uniform in temperature. The pupfish spend the nights in the shallowest, coolest areas of the pools. At dawn they move into the warmest, deepest areas. Later in the morning, during the summer, they work their way into the shallow parts of the pool. Then they retreat from the shallows when the water cools to 36-37 degrees Celsius or below. During the winter the pupfish do not move into the shallows until mid-afternoon and they remain there into the night.

Black, G.F. 1980. Status of the desert pupfish, Cyprinodon macularius (Baird and Girard) in California. California Department of Fish and Game. Inland Fisheries Endangered Species Program Special Publication 80-1. March 1980.(Full Report)
ABSTRACT: Evidence from various sources demonstrates that the distribution of the desert pup fish, Cyprinodcn rnacularius, has declined in California. The species was once endemic to the Colorado River and numerous springs throughout the Salton Sink, but is presently found only in the Salton Sea and some of its tributaries. Casual observations by numerous individuals indicated that their distribution and numbers within these areas had become severely reduced in recent years, reportedly due to loss of habitat and proliferation of exotic species.

To assess the distribution and relative abundance of desert pupfish, surveys were conducted quarterly at various locations in and around the Salton Sea. Minnow traps were used to sample fish within irrigation drains, shoreline pools, three permanent natural tributaries, and the Salton Sea proper between March 1978 and January 1979. San Felipe Creek, an intermittent tributary to the Salton Sea, was also surveyed in November 1978 and March 1979 following a report by the Bureau of Land Management that pupfish had been observed there.

Thirteen nonnative species of fish and one invertebrate species were collected in addition to the desert pupfish. The latter comprised 3% of the total catch from the four surveys of the irrigation drains, 5% of the catch from the shoreline pools, and less than 1% of the catch from the natural tributaries and the Salton Sea proper. On the other hand, the sailfin molly, Poecilia latapinna, accounted for 85% of the total catch in the irrigation drains, 81% of the catch in the shoreline pools, 70% of the catch from the natural tributaries, and 98% of the catch in the Salton Sea proper. The status of the pupfish populations in these habitats seems precarious.

By contrast, desert pupfish made up 70% of the total catch from San Felipe Creek. Although several nonnative species were also present, including the sailfin molly, their numbers were low. Thus, San Felipe Creek appears to support a viable population of desert pupfish. Planned agricultural development of several sections of land adjacent to the creek and also land subdivision for housing pose immediate threats to the habitat. Pumping of ground water to supply these developments may eliminate the surface flow in San Felipe Creek.

Because the desert pupfish has undergone a significant reduction in its range, and due to existing threats to the only viable natural populatioon remaining in California, the desert pupfish qualifies for listing as an endangered species under both State and Federal endangered species acts. Cooperation between County, State, and Federal governments as well as the private sector will be necessary to prevent this species from becoming extinct in California.

Black, G.F. 1988. Description of the Salton Sea sport fishery, 1982-1983. Inland Fisheries Administrative Report No. 88-9. (Full Report)
ABSTRACT: An angler creel census was conducted at the Salton Sea, California, from October 1982 through September 1983, to determine catch-per-unit-effort, catch composition by area, angler type (shore, jetty, or boat), size of fish caught and area of angler origin. Census clerks interviewed 19,053 anglers who fished 70,756 hours and caught 103,301 sportfish at an average catch rate of 1.46 fish per hour.

The Mozambique mouthbrooder, Tilapia mossambica, made up 41% of the total sportfish catch, followed by bairdiella (croaker), Bairdiella icistia, and sargo, Anisotremus davidsoni, at 28% each, and orangemouth corvina, Cynoscion xanthulus, at 3%. The Tilapia catch represents the first reported California sportfishery for this genus. The redbelly tilapia, Tilapia zillii, was not found during this census, even though it a occassionally been seen in angler and Department of Fish and Game gill net catches during the late 1970's. Mean angler catch rates in fish per hour were 0.60 for tilapia, 0.41 for bairdiella and sargo, and 0.04 for corvina. Angler effort was highest from February through June. In terms of catch per hour, the data show that the Salton Sea sportfishery is one of California's highest quality fisheries.

Angler origin has changed little since 1966-69. A total of 75% of Salton Sea anglers came from outside of Imperial and Riverside counties, with Los Angeles County contributing the largest percentage (37%). Length measurements together with size-at-sexual maturity information for corvina caught by sport anglers suggest that a significant portion were removed prior to sexual maturity. Similar data for tilapia, bairdiella, and sargo do not indicate premature exploitation.

Brocksen, R. W. and R.E. Cole. 1972. Physiological responses of three species of fishes to various salinities. Journal of the Fisheries Research Board of Canada, 29:399-405.
ABSTRACT: The effects of varying salinity on parameters such as growth, food consumption, food conversion efficiency, and respiration were determined for three species of fish inhabiting the Salton Sea, California. Bairdiella (Bairdiella icistia ), orangemouth corvina (Cynoscion xanthulus ), and sargo (Anisotremus davidsoni ), were subjected to salinities ranging between 29 and 45 ppt. The optimal range of salinity was between 33-37 ppt for all three species. Growth, food consumption, food assimilation, and respiration were adversely affected at the extreme salinities of 29 and 45 ppt. The results indicate that the fish inhabiting the Salton Sea will experience difficulty in maintaining populations of the current size when the salinity reaches 40 ppt.

CIC Research, Inc. 1989.The economic importance of the Salton Sea sportfishery. A Report to the California Department of Fish and Game. October 1, 1989.(Full Report)
ABSTRACT: The Salton Sea is a major southern California recreation area largely because of the sportfishery. The fish and other wildlife of the Sea are threatened by rising salinity. There are technically feasible ways for controlling the rising salinity, and ways of maintaining the wildlife until broader controls can be instituted. However, a proper evaluation of such measures requires an estimate the value of the Salton Sea as a recreation area, and its importance to the local economy.

A study in 1969 measured an annual use rate of 1.5 million recreation days with about two-thirds of that total accounted for by sportfishing. The same study projected a use level of 4.3 million recreation days by the year 2,010 assuming the Sea's viability as a sportfishery was maintained.

The present study is based on telephone interviews with 14,767 randomly selected southern California households and over 2,059 interviews at various Salton Sea locations. The study estimates that 154,600 households used the Salton Sea for recreation purposes at least once during the last year. Based on average household size in the southern California Counties this would represent 389,095 people. The average group size reported by this sample (5.8) was over twice as large as the average household indicating that the typical group contained more than one household. An additional sample representing another 642,490 southern California households reported using the Salton Sea, but not as recently as the preceding 12 months. Combining the two results in an estimated 797,090 user households in southern California or just over 2 million southern Californians who have used the Salton Sea.

The sample representing 154,600 recent user households reported using the Salton Sea for recreation an average of 6.7 days in 1987. This is an annual use rate of about 2.6 million recreation days.

The (154,600) households directly spent $76 million in 1987, which is just under $30 per recreation day and an average of over $490 per year per household. These direct expenditures give rise to secondary economic impacts including: (1) the indirect (input) requirements needed to supply the goods and services purchased by the Salton Sea recreation user and (2) the income payments resulting from the $76 million direct expenditure which leads to additional rounds of expenditures.

The overall level of Salton Sea user spending ($76 million) generates an additional $128.6 million in output, and household income of $91.8 million for a total economic impact of $296.3 million. Although $53 million of the $76 million in direct expenditures (70%) takes place in the Salton Sea local area, only $27 million of the total additional output and $19.4 million of household income occurs in the local area. Thus the total impact in the local area is $99.2 million of the region-wide $296.3 million. Most of the remaining $197.1 million impact takes place in the larger urban centers of southern California. This volume of economic activity provides the equivalent of 2,633 jobs region-wide, and a substantial number of these jobs (1,486) are in the two counties where the Sea is located. This is particularly critical because this region of the State has a chronic unemployment rate that ranks among the highest in the country.

Both recent and not recent users feel strongly about preserving the fish and wildlife of the Sea. Nearly 75 percent of not recent users and over 80 percent of recent users would support the establishment of user fees to be used for this purpose. An annual user fee of $5.00 per adult would generate as much as $1.4 million per year if applied to all users, over $600 thousand of this would come from anglers.

Dill, W.A. and C. Woodhull. 1942. A gamefish for the Salton Sea, the ten-pounder, Elops affinis. California Fish and Game 28: 171-174.
NOTES: This first record of ten-pounders, Elops affinis, indicated that a sportfishery might be established at the Salton Sea. This gamefish is common in the Gulf of California and was first reported in the Colorado River at Laguna Dam, 12 miles above Yuba, Arizona, in 1942. It is possible for fishes to migrate from the river into the Salton Sea by way of the Alamo and New rivers. At this time the only fishes known to have been present in large numbers are: mullet, Mugil cephalus ; desert minnows, Cyprinodon macularius (a native of the Salton Sink); mosquitofish, Gambusia affinis affinis, Carp, catfishes, and a few sunfishes were reported to occur in the Sea, but were only common at the mouths of the Alamo and New rivers where the water is fresher.

Evermann, B.W. 1916. Fishes of the Salton Sea. Copeia 34: 61-62.
NOTES: Provides a species list with qualitative notes on distribution, abundance and condition of fish known to be present in the Salton Sea as of May, 1916. The species listed are carp, Cyprinus carpio, bony-tail, Gila elegans, humpback sucker, Xyrauchen cypho, Colorado River trout, Salmo pleuriticus, common mullet, Mugil cephalus, and desert pupfish, Cyprinodon macularius.

Gobalet, K.W. 1992. Colorado river fishes of Lake Cahuilla, Salton Basin, Southern California: a cautionary tale for zooarchaeologists. Bulletin of the Southern California Academy of Sciences 91:70-83.
ABSTRACT: Since the late Pleistocene the Colorado River has periodically filled the Salton Basin of southern California to form a huge lake, Lake Cahuilla. Fish remains recovered from archaeological sites occupied about 500 years B.P. along the shores of the last highstand of this lake have been identified as razorback sucker, Xyrauchen texanus, Colorado squawfish, Ptychocheilus lucius, striped mullet, Mugil cephalus, machete, Elops affinis, and bonytail, Gila elegans. For a number of reasons some of these identifications are considered tentative; the zoogeographic basis is doubtful (G. robusta, G. cypha, and the sucker Catostomus latipinnis may also have been present), taxonomic imprecision makes early range determinations unreliable, the remains are fragmentary, and individual variation and potential hybridization make definitive determinations challenging. Zooarchaeologists need to be aware of and address these types of difficulties when they are encountered.

Hanson, J.A. 1970. Salinity tolerances for Salton Sea fishes. California Department of Fish and Game. Inland Fisheries Administrative Report 70-2.
SUMMARY: Salinity tolerances were determined for bairdiella (Bairdiella icistuis), orangemouth corvina (Cynoscion xanthulus), and sargo (Anisotremus davidsoni). In 96-hour shock bioassays, over half the bairdiella died at salinities 55 and 57.5 ppt, and only 2 of 30 survived at 62.5. Most orangemouth corvina survived to 57.5 ppt, but all died at 62.5. Significant numbers of sargo died at all levels from 45 through 57.5 ppt, and all died at 62.5. Survival of sargo in the controls was only 89.6%, suggesting that some mortality was caused by other factors. Bairdiella, given an opportunity to adjust to hypersalinity, survived for eight days 58 ppt.

Hendricks, I.J. 1961. Threadfin shad, Dorosoma petenense Gunther. Pp. 93-94 in B.W. Walker, editor. The ecology of the Salton Sea, California, in relation to the sportfishery. California Department of Fish and Game Fish Bulletin. No. 113: 204 pp.
SUMMARY: Threadfin shad entered the Sea from irrigation laterals in 1955. They were present at all times of year, but appeared to be most numerous during summer months. Recruitment was from fish entering through freshwater inlets. There was no spawning in the Sea. They are planktonic feeders, and thus may develop an important additional food chain to the orangemouth corvina, providing a direct link between plankton and corvina.

Hendricks, I.J. 1961. The striped mullet, Mugil cephalus Linnaeus. Pp. 95-104 in B.W. Walker, editor. The ecology of the Salton Sea, California, in relation to the sportfishery. California Department of Fish and Game Fish Bulletin. No. 113: 204 pp.
SUMMARY: The striped mullet, once abundant in the Salton Sea, is now scarce. The recruitment was from young fish, produced in the Gulf of California, that reached the Sea through the Colorado River, irrigation canals, and drains. Recruitment was almost entirely stopped when the Imperial Dam and All-American Canal were completed in 1942. Nearly all of the mullet in the Sea in 1956 were 14 or more years old.

Hulquist, R.G. 1981. A summary of Salton Sea creel censuses, 1958, 1963 through 1967, and 1969. California Department of Fish and Game, Inland Fisheries, Region 5 Information Bulletin 0004-3-1981. (Full Report)
ABSTRACT: The Salton Sea, a 932.4 km2 (360 mile2) inland sea, located in southwestern California, was formed by flooding waters of the Colorado River during 1905-1907. For over 40 years after its formation it lay undeveloped as a sport fishery. Attempts were made by the Department of Fish and Game to establish various fresh water and marine game fishes in this saline water, but were unsuccessful until the Department introduced marine species from the Gulf of California, during 1950-1956. Of the more than 31 species introduced, only three survived to form the existing sport fishery: the orangemouth corvina, Cynoscion xanthulus Jordan and Gilbert; sargo, Anisotremus davidsoni (Steindachner); and a croaker, Bairdiella icistma (Jordan and Gilbert). By 1958, it appeared a sport fishery was forming. A 34-day creel census, was conducted from October 22, 1958 through January 4, 1959, provided proof that a sport fishery existed for these three species.

In 1963, in order to evaluate angler use and harvest, weekend creel censuses, which incorporated angler use counts from an aircraft and routine ground census stations, were designed and tested. With modifications, a census program was begun in 1964. Sampling periods consisted of six weekends each year.

This paper summarizes the census methods and results during 1958, and from 1963 through 1967, and 1969. From 1958, when the first documented catches were made, the fishery grew rapidly. In 1965 an estimated 540,000 corvina, 148,000 bairdiella and 143,000 sargo were harvested. In 1969 309,000 corvina were taken and the bairdiella and sargo catch peaked at 573,000 and 297,000 fish respectively.

In 1969 the catch dropped to 91,000 corvina, 157,000 sargo and 386,000 bairdiella. Angler use fell from a high of 377,000 angler days in 1965; and 355,000 in 1967 to 246,000 in 1969.

Knaggs, E.H. 1977. Status of the genus Tilapia in California's estuarine and marine waters. Cal-Neva Wildlife Transactions 1977:60-67.
ABSTRACT: Breeding populations of Tilapia mossambica are now established in southern California marine and estuarine waters. Tilapia zillii has been collected twice in the marine environment. Survival in the marine environment, establishment of populations, geographic ranges, and the possible effect on other species are discussed.

Lasker, R., R.H. Tenaza and L.L. Chamberlain. 1972. The response of Salton Sea fish eggs and larvae to salinity stress. California Fish and Game 58:58-66.
ABSTRACT: In laboratory experiments, Salton Sea water at salinities (S) of 40 parts per thousand and higher adversely affected developing embryos and larvae of the croaker, Bairdiella icistia, and the sargo, Anisotremus davidsoni. Embryos developed abnormally, hatching success diminished, and mortality of larvae was greater than in normal Salton Sea water at 37.6 parts per thousand S.

Lau, S. and C. Boehm. 1991. A distribution survey of Desert Pupfish (Cyprinodon macularius) around the Salton Sea, California. Final Report for Section 6, Project No. EF90XII-1. Prepared for California Department of Fish and Game, Inland Fisheries Division. November, 1991.

Matsui, M.L., A.B. Bond, G. Jordan, R. Moore, P. Garrahan, K. Iwanaga, and S. Williams. 1991a. Abundance and distribution of the ichthyoplankton in the Salton Sea, California in relation to water quality. Final Report. Federal Aid project F-51-R, Study No. 3. California Department of Fish and Game. Sacramento, California.
ABSTRACT: The relative distribution and abundance of ichthyoplankton in the Salton Sea was determined by sampling 11 sites monthly during 1987 and semimonthly in 1988 and 1989. During the years of the survey, the total dissolved solid (TDS) level fluctuated from 38 ppt in 1987 to 44 ppt in 1989. Although early developmental stages of eggs continued to exist in the plankton as the TDS levels continued to increase, each successive year the number of ichthyoplankton declined as the result of a significant decline in both the late egg and early larval stages for Cynoscion xanthulus and Anisotremus davidsoni. The exception to this was Bairdiella icistia with significantly more late larvae occurring in samples with each progressive year.

Matsui, M.L., G.L. Lattin, R. Moore, C. Mulski. and A.B. Bond. 1991. Salinity tolerance of Anisotremus davidsonii. Final Report, Federal Aid Project F-51-R, Study No. 2. California Department of Fish and Game. Sacramento, California.
NOTES: Laboratory salinity bioassays were used to estimate the adult reproductive potential and fertilization and hatching success of sargo (Anisotremus davidsonii ) at increasing levels of total dissolved solids (35, 40, 45, 50, and 55 ppt). Fish were collected from the Salton Sea, acclimated in the laboratory to Salton Sea water at these five levels and allowed to spawn naturally. Sargo did not spawn at 50 and 55 ppt and spawns at the remaining three salinities were asynchronous. Hatching success experiments consisted of four replicates of 100 eggs/beaker/salinity treatment. Egg mortality ranged across all treatments through time from three to 31%. There was a significant effect of parental salinity on egg mortality with lower parental salinity associated with a higher egg mortality. This may have been an artifact of the experimental design producing confounding temporal effects (45 ppt were run in June while the 35ppt were run in September). Eggs spawned by adults acclimated to 45 ppt water produced viable fertilized eggs, but the eggs failed to develop past the blastopore closure stage. Larval mortality varied from 66-76% and treatment salinity had a significant effect. At high salinities all the larva died.

Matsui, M.L., G.L. Lattin, R. Moore, C. Mulski. and A.B. Bond. 1991b. Salinity tolerance of Anisotremus davidsonii. Final Report, Federal Aid Project F-51-R, Study No. 2. California Department of Fish and Game.

Matsui, M.L., G.L. Lattin, R. Moore, C. Mulski, and A.B. Bond. 1991c. Salinity tolerance of Cynoscion xanthulus. Final Report, Federal Aid Project F-51-R, Study No. 2 California Department of Fish and Game.

Matsui, M.L., G.L. Lattin, R. Moore, C. Mulski, and A.B. Bond. 1991. Salinity tolerance of Cynoscion xanthulus. Final Report, Federal Aid Project F-51-R, Study No. 2 California Department of Fish and Game. Sacramento, California.
ABSTRACT: Eggs and larvae of the sciaenid fish Orangemouth Corvina, Cynoscion xanthulus, were obtained from fish matured in the laboratory by photoperiod and temperature manipulation and induced to spawn by LH-RHa injections. The effects on gametes of parental salinity acclimation were also investigated. Successful gonadal maturation occurred in adult corvina acclimated to 35 through 50 ppt salinity. Significant growth also occurred in individuals acclimated to 35 through 50 ppt salinity. Reproductive failure of this species will occur with increased salinity due to insufficient osmotic capability in the eggs and larvae.

Matsui, M., J. E. Hose, P. Garrahan, G. A. Jordan, 1992. Developmental defects in fish embryos from Salton Sea, California. Bulletin of Environmental Contamination and Toxicology 48 No.6 914-920.
NOTES: Field collected and lab spawned eggs from Salton Sea fish were evaluated for deformities. Field collected sargo eggs generally had a higher incidence of deformities at the end of the 1987 and 1988 breeding seasons. This pattern was not observed in 1989. The monthly deformity values for sargo ranged over three years from zero to 62.4%. In contrast incidences of abnormal sciaenid (croaker + corvina) eggs did not follow any temporal pattern and the overall incidence of deformed embryos was lower than that of sargo. Retarded development of the nervous system was the prevalent malformation in all groups of fish as detected by histopathological examination. Fish collected from the Salton Sea were spawned in the laboratory under a controlled temperature:photoperiod regime designed to simulate the environmental conditions present at the Sea during the breeding season. Two groups of sargo embryos evaluated at stage V of development had 9.9% and 15.8% abnormalities. The malformation rate of a third sargo spawn evaluated at an earlier stage of development (stage IV) was higher, 24.9%. Corvina exhibited malformation rates of 5.7% at stage V and 10.9% at stage VI. The types of defects observed were identical in both fish species and included incomplete blastopore closure and retarded cranial development.

May, R. 1975. Effects of temperature and salinity on fertilization, embryonic development, and hatching in Bairdiella icistia (Pisces:Sciaenidae), and the effect of parental salinity acclimation on embryonic and larval salinity tolerance. Fishery Bulletin 73(1):1-21.
ABSTRACT: Eggs and larvae of the sciaenid fish bairdiella, Bairdiella icistia, were obtained from fish matured in the laboratory by photoperiod manipulation and induced to spawn by hormone injections. The effects of temperature and salinity on fertilization, embryonic development, hatching, and early larval survival were studied with the material thus obtained, and the effects on gametes of parental salinity acclimation were also investigated. Fertilization took place over a wide range of temperatures and salinities, but was completely blocked at salinities of 10 ppt and below. A low level of spermatozoan activity may have accounted for the lack of fertilization at low salinities. Successful embryonic development occurred between temperatures of approximately 20 degrees and 30 degrees C, and salinities of 15 and 40 ppt. The production of viable larvae was estimated to be optimal at a temperature of 24.5 degrees C and a salinity of 26.6 ppt. An interaction of the two factors was apparent, development at high salinities being most successful at low temperatures and development at high temperatures being most successful at low salinities. The stage of maturity of the spawning female had a great influence on the overall viability of the eggs produced, as well as on their response to temperature and salinity. Adult bairdiella matured sexually in dilute seawater with a salinity of 15 ppt, and the salinity tolerance of the eggs produced by these fish was unaltered.

May, R. 1975. The effects of acclimation on the temperature and salinity tolerance of the yolk-sac larvae of Bairdiella icistia. (Pisces:Sciaenidae). Fishery Bulletin 73:249-255.
ABSTRACT: Eggs of the bairdiella, Bairdiella icistia, were fertilized and incubated in various combinations of temperature and salinity, and the salinity and upper thermal tolerances of the yolk-sac larvae were determined. The upper thermal tolerance was enhanced by acclimation to high temperatures and low salinities. Acclimation to low salinities enhanced the lower salinity tolerance of larvae at 24 h after exposure to test conditions, but an acclimation effect on the upper salinity tolerance was not apparent until 48 h after exposure. Yolk-sac bairdiella larvae are more tolerant than embryonic stages and less tolerant than adults to extremes of temperature and salinity.

May, R. 1975a. Effects of temperature and salinity on fertilization, embryonic development, and hatching in Bairdiella icistia (Pisces:Sciaenidae), and the effect of parental salinity acclimation on embryonic and larval salinity tolerance. Fish. Bull. 73(1):1-21.

May, R. 1975b. The effects of acclimation on the temperature and salinity tolerance of the yolk-sac larvae of Bairdiella icistia. (Pisces:Sciaenidae). Fish. Bull. 73(2):249-255.

May, R. 1976. Effects of Salton sea water on the eggs and larvae of Bairdiella icistia. California Fish and Game 62: 119-131.
ABSTRACT: In laboratory experiments, eggs and early larvae of the sciaenid fish Bairdiella icistia survived well in sea water but displayed extremely poor survival in water from the Salton Sea. Mortality in Salton Sea water was expressed mainly among hatched larvae prior to complete yolk absorption. Experiments conducted in both natural and artificial sea water and Salton Sea water indicated that this poor survival was related to the unusual ionic composition of the Salton Sea.

Nordlie, F.G., D.C. Haney and S.J. Walsh. 1992. Comparisons of salinity tolerances and osmotic regulatory capabilities in populations of sailfin molly (Poecilia latipinna) from brackish and fresh waters. Copeia 1992:741-746.
ABSTRACT: Sailfin mollies, Poecilia latipinna, inhabit both fresh and brackish waters throughout their native range. In laboratory analyses, following extensive acclimation, individuals taken from freshwater populations tolerated a range of ambient salinities from fresh water through 70 ppt, whereas individuals from brackish water tolerated salinities ranging from fresh water through 80 ppt. Plasma osmotic concentrations of the two groups were not significantly different at common ambient salinities over the range from fresh water through 75 ppt. Isolation in nature of populations in fresh and brackish waters has not greatly altered their physiological capabilities with respect to ambient salinity.

Popper, D. and T. Lichatowich. 1975. Preliminary success in predator contact of Tilapia mossambica. Aquaculture 5:213-214.
ABSTRACT: In this short communication, the results of some preliminary experiments are presented which indicate that the population of Tilapia mossambica in seawater ponds might be controlled by allowing unlimited numbers of Elops hawaiiensis into the ponds.

Quast, J.C. 1961. The food of the bairdiella. Pp. 153-164 in B.W. Walker, editor. The ecology of the Salton Sea, California, in relation to the sportfishery. California Department of Fish and Game Fish Bulletin. No. 113: 204 pp.
SUMMARY: The pile worm, Neanthes succinea, formed practically the entire diet of bairdiella over 30 mm long. Young fish ate barnacle nauplii and all stages of copepods. They all consumed a significant number of bairdiella eggs and larvae. The food intake of adults was heavier at night, correlating with the spawning of Neanthes. The most important limiting factor for bairdiella was the scarcity of Neanthes during the summer and early fall. These periods coincide with anoxic conditions in the deeper waters of the Sea. Food for bairdiella was most abundant during the spring. Experiments indicated that fish with full stomachs required more than 16 hours to complete gastric digestion

Saiki, M.K. 1990. Elemental concentrations in fishes from the Salton Sea, southeastern California. Water, Air and Soil Pollution 52:41-56.
ABSTRACT: The Salton Sea is a 93,000 ha saline lake fed by drainage water from more than 283,000 ha of irrigated lands in the Imperial and Coachella valleys of California. A total of 21 composite samples of four recreationally important fish species - bairdiella (Bairdiella icistia), orangemouth corvina (Cynoscion xanthulus), sargo (Anisotremus davidsoni), and Mozambique tilapia (Tilapia mossambica) - collected there were analyzed for 14 elements. Twelve of these elements were detected in one or more of the samples: As, B, Co, Cu, Fe, Hg, Mo, Ni, Pb, Se, V, and Zn. Cadmium and Tl were not detected. The ranges in concentrations of elements in the skinless fillets of bairdiella, corvina, and sargo, and in whole bodies of all four fishes were comparable to levels that are typically measured in saltwater fishes. Only Se concentrations were elevated (as much as 14 mg g-1 dry weight in both fillets and whole bodies) in this series of samples. Elevated concentrations of Se have already led to public health advisories concerning the consumption of fish and might eventually cause the demise of fish populations from toxic effects.

St. Amant, J.A. 1966. Addition of Tilapia mossambica to the California fauna. California Fish and Game 52: 54-55.
NOTES: Details the first verified record of free-living tilapia (Tilapia mossambica) in California. Tilapia were observed on January 3, 1964 in a 0.25-acre pond and its tributary five miles north of the Salton Sea near Hot Mineral Spa , Imperial County. A tropical fish farm, located directly below the pond and which had cultured tilapia, may have been the source of this introduction. Attempts at eradication failed and a breeding population became established in this small drainage. Mosquitofish, Gambusia affinis, sailfin molly, Poecilia latipinna, and desert pupfish, Cyprinodon macularius , were also present in this tributary.

Schoenherr, A.A. 1979. Niche separation within a population of freshwater fishes in an irrigation drain near the Salton Sea, California. Bulletin of the Southern California Academy of Science 78: 46-55.
ABSTRACT: The fish fauna of the King Street canal is a mixture of native and introduced species. Inflow from a thermal well at 42 degrees C and irrigation runoff at 22 degrees C were responsible for a thermal gradient that, in addition to differences in flow, held fishes in remarkably pure species populations. On 19 March 1977, Cyprinodon macularius was found most abundantly in water 10 cm deep at 39 degrees C. Gambusia affinis occurred in flowing water 25 cm deep at 32 degrees C. Only Poecilia sphenops inhabited a cool water outflow 18 cm deep 22 degrees C. Downflow, Poecilia latipinna was taken most commonly in slow moving water up to 50 cm deep at 26 degrees C, and Notropis lutrensis occurred in riffles up to 25 cm deep at similar temperatures. Flooding during late summer 1977 and subsequent reconstruction of the canal obliterated most of the habitat diversity. All five species survived, albeit seriously reduced in number, and the species sorting that was previously observed also was no longer in evidence. Thermal differences remained, and a pond was constructed that impounded hot water. Later, on 17 July 1978, the pond included Cyprinodon macularius, Gambusia affinis, Poecilia latipinna and a new introduction, Tilapia zilli. Downstream, Cyprinodon macularius, Poecilia spenops, and Notropis lutrensis were taken in flowing water.

Thompson, W.F. and H.C. Bryant. 1920. The mullet fisheries of Salton Sea. California Fish and Game 6:60-63.
NOTES: Provides an account of early attempts to establish a commercial fishery at the Sea. Early entrepreneurs failed to establish a carp fishery immediately after the Sea's formation. However in 1915 mullet (Mugil cephalus ) began to appear in the Sea. Although early attempts to market these fish were unsuccessful, a market for mullet was eventually established in Los Angeles and San Francisco providing the necessary financial support for a commercial fishery. Mullet were caught near the mouths of the rivers using halibut trammel nets and two men using eight trammel nets of thirty fathom lengths each could catch 250-300 pounds daily during the winter months. Fishermen received 15 cents a pound for their catch. Mullet were large, between two and two and one-half feet in length, and yielded a quart of oil to the ten pounds of fish. Desert pupfish (Cyprinodon macularius) were said to have been abundant in the Sea at times and were collected from Fish Spring. Some information on fish kills, water chemistry, salinity, lake level, basin morphology, geology, mullet distribution, and weekend visitation also is given.

Walker, B.W., R.R. Whitney, and G.W. Barlow. 1961. The fishes of the Salton Sea. Pp. 77-92 in B.W. Walker, editor. The ecology of the Salton Sea, California, in relation to the sportfishery. California Department of Fish and Game Fish Bulletin. No. 113: 204 pp.
SUMMARY: In 1949 there were four species of fishes in the Sea: desert pupfish, Cyprinodon macularius; mosquitofish, Gambusia affinis affinis ; striped mullet, Mugil cephalus ; and longjaw mudsucker, Gillichthys mirabilis. None of these could provide a sportfishery.

The California Department of Fish and Game, during the years 1949 to 1956, introduced large numbers of many species of fishes from San Felipe, Baja California, with the hope of establishing a sportfishery. Three of the introduced species are now established in the Sea: bairdiella, Bairdiella icistius ; orangemouth corvina, Cynoscion xanthulus ; and sargo, Anisotremus davidsoni. Shortfin corvina, Cynoscion parvipinnis, have also been recovered in the Sea, but there is no evidence that it has reproduced. Threadfin shad, Dorosoma petenense, entered the Sea in 1955 from the Colorado River.

The desert pupfish and the mosquitofish were confined to the extreme marginal areas of the Sea, and were of little importance. The longjaw mudsucker was more widespread, and formed a minor item in the diet of the orangemouth corvina. It was not a serious competitor with the gamefishes in the Sea.

Walker, B.W., R.R. Whitney, and L.H. Carpelan. 1961. General considerations and recommendations. Pp. 185-192 in B.W. Walker, editor. The ecology of the Salton Sea, California, in relation to the sportfishery. California Department of Fish and Game Fish Bulletin. No. 113: 204 pp.
SUMMARY: The most important food chain to the sportfishery is: phytoplankton --> zooplankton --> detritus --> detritus eating worm (Neanthes) --> worm-eating fish (bairdiella and sargo) --> fish-eating fish (corvina). The weakest link in this chain is at the level represented by Neanthes. This single species is the only organism in the Sea converting detritus into food for bairdiella and sargo. This stage in the chain is probably strong in regards to efficiency, however. Of secondary importance is the food chain: phytoplankotn --> zooplankton --> threadfin shad --> corvina.

Management recommendations are based solely on biological grounds, and only those actions which would directly benefit the fishery are encouraged. We think it best to limit the fish fauna to a few forms. In this way production of the most desirable species should be highest. We recommend a conservative attitude toward introducing new forms. New fishes should be planted only if the present fishery proves inadequate. Zooplankters which would strengthen the food chain during summer would be desirable. Mysids and amphipods would strengthen the food chain at the Neanthes level. and should be introduced. Sampling of the bairdiella, sargo, and corvina populations should be continued to secure information on growth and catch. At least qualitative checks on the faunal composition should also be continued. We recommend high rates of fish harvest. We see no reason for special limits on bairdiella or sargo, or for a low limit on the orangemouth corvina, or for closed seasons. Methods to control the salinity of the Sea should be investigated.

Whitney, R.R. 1961. The bairdiella, Bairdiella icistius Jordan and Gilbert. Pp. 105-152 in B.W. Walker, editor. The ecology of the Salton Sea, California, in relation to the sportfishery. California Department of Fish and Game Fish Bulletin. No. 113: 204 pp.
SUMMARY: Sixty-seven bairdiella, Bairdiella icistius (Jordan and Gilbert), were introduced into the Salton Sea by the California Department of Fish and Game in 1950 and 1951. First successful spawning was in 1952, and the fish is now firmly established in the Sea. Spawning occurred from April to August, with a decided peak in May, but spawning after the middle of June produced very few fry. Bairdiella eggs were broadcast in the open water, where they tended to float just under the surface. Spawning took place in the evening from 6 to 10 PM, Pacific Standard Time. The eggs hatched in 24 hours at 72 to 74 degrees F., which was the water temperature during the peak of the spawning season.

A dominant year-class was produced in 1953 which grew slowly, suppressed the growth of 1952 year-class fish, and prevented success of the 1954, 1955, and 1956 year-classes. The 1953 year-class fish reached a length of only 76 mm in their fist year, while 1952 year-class fish had reached at least 100 mm. The fish of the 1953 year-class increased only slightly in length each year. This growth occurred during the spring when the most food was available. Fish of the 1952 year-class showed no increase in average length after 1953.

Bairdiella moved toward shore in the summer and away from shore in the winter. The movement was probably influenced by the availability of food, as shown by weight gains and losses. Mortalities occurred annually in the Salton Sea, most commonly the late summer or early fall. Large numbers of dead fish were washed up on shore. They were losing weight at the time of the kills. K factor of 1.6 or less coincided with kills.

Minor fish kills might have occurred at times due to oxygen shortage though the main effect of the oxygen depletion in deeper waters was the elimination of the food supply. Serious abnormalities were common in fish of the 1952 year-class year-class and 23 percent showed some evident deformation. Only one percent of the fish of the 1953 year-class showed similar abnormalities. The percentage of abnormal fish in the 1952 year-class dropped in 1953. The change in percentage of abnormal fishes almost certainly was due to a great change in competition and predation in 1953.

An annulus formed on scales of 1953 year-class fish each spring when the fish increased in length after a period of dormancy. Fish of the 1952 year-class failed to form annuli on the scales in some years, so that in 1956 most of them had fewer annuli than the younger, smaller fish of the 1953 year-class.

Whitney, R.R. 1961. The orangemouth corvina, Cynoscion xanthulus Jordan and Gilbert. Pp. 165-184 in B.W. Walker, editor. The ecology of the Salton Sea, California, in relation to the sportfishery. California Department of Fish and Game Fish Bulletin. No. 113: 204 pp.
SUMMARY: Small numbers of orangemouth corvina, Cynoscion xanthulus, were planted in the Salton Sea in 1950,1951, and 1952 by the California Department of Fish and Game. First successful spawning in the Salton Sea occurred in 1920 and continued each year thereafter. A gradual increase in the population of corvina was shown by the increased catch, especially of later year-classes, in gill nets and seines. A population of 40,000 corvina in 1956 was estimated from recaptures of fin-clipped corvina introduced from the Gulf of California. The estimate included year-classes up to and including the 1955. The 1956 and 1957 year-classes were about 20 times as abundant as the previous year-classes had been at comparable ages.

In 1955, two groups of corvina with different growth rates appeared apparently from a spring spawning. Availability of small fish as food was thought to explain their differences in growth. After an initial slow phase, the corvina grew very rapidly, typical year-classes reaching weights of 2 1/2 pounds by their second winter, 5 1/4 pounds by their third, and 11 by their fourth. Faster-growing segments of the 1955 and 1957 year-classes reached weights of 1 pound by the end of their first year, and 3 3/4 pounds by the end of their second.

Corvina up to about 30 mm fed on copepods, barnacle nauplii, and cyprids. At a length between 30 and 60 mm they shifted to feeding on the pile worm. This caused severe competition with bairdiella which also utilized Neanthes for food. Most young-of-the-year corvina grew at about the same rate as bairdiella, so they were unable to feed on fish until the following spring, when spawning bairdiella produced a new supply of small fish. In some years, as in 1955 and 1957, groups of faster-growing corvina apparently reached a sufficient size by the fall of the first year to feed on bairdiella. There was an immediate increase in growth rate at this time. Large corvina fed primarily on Bairdiella, but also mudsuckers and threadfin shad.

The gonads of the orangemouth corvina matured in April and May. The number of eggs per female was estimated as 400,000 to 1,000,000. Eight percent of the corvina in the Salton Sea showed some abnormality.

Whitney, R.R. 1969. Introduction of commercially important species into inland mineral waters. Contributions in Marine Science 12: 263-276.
ABSTRACT: The successful introductions of commercially important animals into inland mineral waters of the following four categories were reviewed.

1. Lagoons. These have been modified into ponds and used for the culture of marine animals in Europe and Asia. Milkfish, Chanos chanos, cultured most extensively in Asia can survive in ponds with salinities as high as 140 ppt. Mullets, Mugil spp., prawns, Penaeus spp., and other animals can survive up to 70 ppt in these ponds. In Europe, eels, Anguilla anguilla, mullets, Mugil spp. and other fishes are cultured in salinities up to 47 ppt.

2. Relict waters. To improve the food base for fish, man has introduced additional species of fish and invertebrates into the Caspian Sea (salinity 12 to 13 ppt) and the Aral Sea (10 ppt). The mullets, Mugil auratus and M. saliens, were introduced and now support an important fishery in the Caspian Sea. Nereis diversicolor was introduced as a food for fish in the Caspian Sea. The Baltic herring, Clupea harengus, has been introduced into the Aral Sea.

3. Salterns and inland brines. Man has successfully introduced fishes into the Salton Sea, California (salinity 33 ppt), and Lake Quarun, Egypt (29 ppt). Nearly the entire fauna of the Salton Sea, in a food chain leading to a sport fish, Cynoscion xanthulus, was introduced. Mullets, Mugil cephalus and M. capito, and the sole, Solea vulgaris, were introduced into Lake Quarun and are the objects of a commercial fishery.

4. Carbonate and sulfate waters. Whitefish, Coregonus clupeafornis, were introduced into the Quill Lakes, two saline lakes of Saskatchewan, when the salinities were 11 ppt and 17 ppt. They supported a commercial fishery for about 10 years until the salinities reached about 19 ppt. Other introductions were made in lakes of various salinities in the region.

The success of the introduction of commercially important species into these waters suggests that further attempts should be made to introduce animals into hypersaline waters. Effluents from desalinization plants could be used for pond culture of fishes and invertebrates. No waters are too saline for the culture of species useful to man; the economically valuable brine shrimp, Artemia salina, tolerates saturation.

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