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Anthopleura elegantissima sola Chthamalus spp./Balanus glandula
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Haliotis cracherodii Leach, 1814 Black abalone |
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General Description (from Morris et al. 1980): |
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Maximum length over 20 cm; shell exterior dark blue, dark green, or black, smooth, usually epiphytic free; shell holes with rims not elevated above surface, usually five to seven remaining open, occasionally none; shell interior pearly, with pink and green iridescence; tentacles black |
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Habitat and Range (from Morris et al. 1980): |
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High intertidal zone to 6 m depth, most abundant intertidally; Coos Bay (Oregon) to Cabo San Lucas (Baja California) |
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Haliotis cracherodii was once abundant in the intertidal zone |
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Biology: |
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Juveniles are usually seen in crevices, whereas, adults are more frequent on exposed rocks (Morris et al. 1980). Abalone prefer kelps (Leighton 1966) and the bulk of their diet consists of brown algae, with small individuals grazing on diatoms and corallines, and larger ones eating drift algae (Morris et al. 1980). Increased temperature has been shown to increase feeding and growth in several other species of abalone (Leighton 1974; Uki et al. 1981; Uki et al. 1982; Hahn 1989; Gao et al. 1990). Growth varies with size, location, and other environmental factors, but growth does appear to be slow (Morris et al. 1980). Although once very abundant (Douros 1987; Richards and Davis 1993), abalone have severely declined in population, causing the fishery in California to close south of San Francisco. Intense fishing and withering syndrome may be the chief reasons for the black abalone population decline. Abalone in southern California and on the Channel Islands disappeared almost completely during the mid-1980s (Lafferty and Kuris 1993; Richards and Davis 1993). Natural predators of abalone include sea otters, sea stars, fishes, and octopus (Morris et al. 1980). Oil impacts are not well known, but black abalone mortality has been shown after an oil spill (North et al. 1965). Due to the low population numbers, low recruitment, and slow growth, recovery from disturbance appear to be long-term (Raimondi et al. 1999). |
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A dense patch of Haliotis cracherodii |
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Haliotis cracherodii with a heavily eroded shell |
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References: |
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Douros WJ (1987) Stacking behavior of an intertidal abalone: an adaptive response or a consequence of space limitation? J Exp Mar Biol Ecol 108:1-14 Gao X, Liu Y, Liu Y, Liu J (1990) Influence of temperature on feeding and growth of the young abalone. Oceanol Limnol Sin 21: 20-26 Hahn KO (1989) Handbook of culture of abalone and other marine gastropods. CRC Press, Boca Raton Lafferty KD and Kuris AM (1993) Mass mortality of abalone Haliotis cracherodii on the California Channel Islands: tests of epidemiological hypotheses. Mar Ecol Prog Ser 96: 239-248 Leighton DL (1966) Studies of food preference in algivorous invertebrates of southern California kelp beds. Pac Sci 20: 104-113 Leighton DL (1974) The influence of temperature on larval and juvenile growth in three species of southern California abalones. Fish Bull 72: 1137-1145 Morris RH, Abbott DL, Haderlie EC (1980). Intertidal invertebrates of California. Stanford University Press, Stanford North WJ, Neushul M, Clendenning KA (1965) Successive biological changes observed in a marine cover exposed to a large spillage of mineral oil. In Proceedings of the Comm Int Explor Scient Mer Merit Symposium on marine pollution caused by micro-organisms and mineral oils, Monaco, pp 335-354 Raimondi PT, Ambrose RF, Engle JM, Murray SN, Wilson M (1999) Monitoring of rocky intertidal resources along the central and southern California mainland. 3-Year Report for San Luis Obispo, Santa Barbara, and Orange Counties (Fall 1995-Spring 1998). OCS Study, MMS 99-0032, U.S. Bureau of Energy Management, Regulation, and Enforcement, Pacific OCS Region Richards DV and Davis GE (1993) Early warnings of modern population collapse in black abalone Haliotis cracherodii, Leach, 1814 at the California Channel Islands. J Shellfish Res 12(2):189-194 Uki N, Grant JF, Kikuchi S (1981) Juvenile growth of the abalone, Haliotis discus hannai, fed certain benthic micro algae related to temperature. Bull Tohoku Reg Fish Res Lab 43: 59-64 Uki N, Kikuchi S (1982) Influence of food levels on maturation and spawning of the abalone, Haliotis discus hannai related to effective accumulative temperature. Bull Tohoku Reg Fish Res Lab 45: 45-52
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