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Aleuts, sea otters, and alternate stable-state communities
Science (New York, N.Y.)
|April 28, 1978
Summary
Aleut prey on Amchitka Island shifted dramatically over 2500 years. This change was likely due to Aleut overexploitation of sea otters, not cultural food preference shifts.
Area of Science:
- Paleoecology
- Archaeology
- Marine Ecology
Background:
- Prehistoric Aleut middens on Amchitka Island reveal long-term faunal changes.
- Aleutian nearshore ecosystems exhibit two stable states: macroalgal or epibenthic herbivore dominated.
- Sea otter populations critically influence these ecosystem states.
Purpose of the Study:
- To reexamine prehistoric Aleut prey selection over 2500 years.
- To investigate the drivers of observed changes in Aleut diet.
- To correlate faunal shifts with paleoecological data.
Main Methods:
- Analysis of stratified faunal remains from an Aleut midden.
- Comparison of faunal data with ecological studies on Aleutian nearshore communities.
- Ecological modeling of predator-prey dynamics.
Main Results:
- Significant changes in Aleut prey items were identified over the 2500-year occupation period.
- Faunal shifts correlate with the ecological requirements for sea otter presence or absence.
- Evidence suggests local sea otter overexploitation by aboriginal Aleuts.
Conclusions:
- Aleut prey composition changes reflect sea otter population dynamics.
- Dietary shifts were driven by ecological factors, specifically sea otter availability, rather than cultural preference.
- Aboriginal Aleut hunting practices likely led to local sea otter decline, impacting nearshore ecosystems.
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