Individual variation in prey selection by sea otters: patterns, causes and implications

Journal of Animal Ecology - Tập 72 Số 1 - Trang 144-155 - 2003
James A. Estes1,2, Marianne Riedman3,4, Michelle M. Staedler3, M. Tim Tinker1, Bruce E. Lyon1
1Department of Ecology and Evolutionary Biology, University of California, Santa Cruz, CA 95064, USA,
2US Geological Survey, Center for Ocean Health, 100 Shaffer Road, University of California, Santa Cruz, CA 95060, USA
3Life Sciences Division, Monterey Bay Aquarium, 886 Cannery Row, Monterey, CA 93940, USA
4Present address: Sequoyah Publishing, PO Box 1415, Capitola CA 95010, USA.

Tóm tắt

SummaryLongitudinal records of prey selection by 10 adult female sea otters on the Monterey Peninsula, California, from 1983 to 1990 demonstrate extreme inter‐individual variation in diet. Variation in prey availability cannot explain these differences as the data were obtained from a common spatial‐temporal area.Individual dietary patterns persisted throughout our study, thus indicating that they are life‐long characteristics.Individual dietary patterns in sea otters appear to be transmitted along matrilines, probably by way of learning during the period of mother–young association.Efficient utilization of different prey types probably requires radically different sensory/motor skills, each of which is difficult to acquire and all of which may exceed the learning and performance capacities of any single individual. This would explain the absence of generalists and inertia against switching, but not the existence of alternative specialists.Such individual variation might arise in a constant environment from frequency‐dependent effects, whereby the relative benefit of a given prey specialization depends on the number of other individuals utilizing that prey. Additionally, many of the sea otter's prey fluctuate substantially in abundance through time. This temporal variation, in conjunction with matrilineal transmission of foraging skills, may act to mediate the temporal dynamics of prey specializations.Regardless of the exact cause, such extreme individual variation in diet has broad ramifications for population and community ecology.The published literature indicates that similar patterns occur in many other species.

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Tài liệu tham khảo

Ames J.A., 1983, Tagging materials and methods for sea otters, Enhydra lutris, California Fish and Game Quarterly, 69, 243

10.1890/0012-9658(1999)080[0288:LTROIW]2.0.CO;2

10.1007/BF00319024

10.1111/j.1474-919X.2000.tb04439.x

10.1080/08927014.1997.9522890

10.1016/S0065-3454(08)60193-X

10.1890/0012-9658(1999)080[2206:QVITSO]2.0.CO;2

10.1111/j.1748-7692.2000.tb00913.x

10.1086/343878

10.1139/f95-845

10.1046/j.1365-2656.1999.00334.x

10.1016/S0003-3472(80)80142-4

10.1086/417553

Clutton‐Brock T.H., 1982, Red Deer: Behavior and Ecology of Two Sexes.

Cohen J., 1988, Statistical Power Analysis for the Behavioral Sciences

10.1139/z82-354

10.2307/1468452

10.2307/1565297

Dawkins R., 1980, Sociobiolog: Beyond Nature/Nurture?, 331

10.1093/icb/24.2.385

10.2307/1940938

10.2307/1937360

Estes J.A., 1981, Worldwide Furbearer Conference Proceedings, 606

10.1126/science.282.5388.473

10.2307/1381127

10.1007/BF01601953

10.1146/annurev.es.19.110188.001231

10.2307/1938360

10.1139/z85-028

10.2307/3546118

10.2307/1942246

10.2307/1937652

10.1016/S0022-5193(85)80286-1

10.1007/BF01049524

10.3996/nafa.68.0001

Krebs J.R., 1987, An Introduction to Behavioural Ecology

Kruuk H., 1995, Wild Otters: Predation and Populations, 10.1093/oso/9780198540700.001.0001

10.1111/j.1469-7998.1990.tb04021.x

Lyons K.J.(1991)Variation in feeding behavior of female sea otters Enhydra lutris between individuals and with reproductive condition.PhD Dissertation. University of California Santa Cruz Santa Cruz CA.

MacArthur R.H., 1972, Geographical Ecology

10.1007/978-1-4684-8261-4_13

Mangel M., 2000, Dynamic State Variable Models in Ecology: Methods and Applications

10.1007/BF00005130

10.1086/284489

10.1007/BF02464838

10.1034/j.1600-0706.2000.900304.x

10.1111/j.1474-919X.1967.tb04014.x

10.1016/S0003-3472(76)80119-4

Partridge L., 1985, Behavioral Ecology, 207

10.3354/meps039275

10.1111/j.1558-5646.1992.tb01133.x

10.1016/S0169-5347(00)01971-6

Ragg J.R., 1998, Intraspecific and seasonal differences in the diet of feral ferrets (Mustela furo) in a pastoral habitat, East Otago, New Zealand, New Zealand Journal of Ecology, 22, 113

10.1139/z96-207

Riedman M.L., 1990, The Sea Otter Enhydra lutris: Behavior, Ecology and Natural History., 90, 1

10.1086/285696

Rosenthal G.A., 1979, Herbivores: Their Interaction with Secondary Plant Metabolites

10.1086/282807

10.1007/s004420050200

Schoener T.W., 1986, Community Ecology. Pattern and Process, 91

10.1038/329717a0

10.1146/annurev.ecolsys.27.1.111

10.1086/284969

10.1046/j.1365-2656.2000.00410.x

10.2307/3565857

10.1007/s004420000373

10.1073/pnas.84.15.5506

10.2307/1937702

10.2307/1941161