Killer whale predation on sea otters linking oceanic and nearshore ecosystems
نویسندگان
چکیده
After nearly a century of recovery from overhunting, sea otter populations are in abrupt decline over large areas of western Alaska. Increased killer whale predation is the likely cause of these declines. Elevated sea urchin density and the consequent deforestation of kelp beds in the nearshore community demonstrate that the otter's keystone role has been reduced or eliminated. This chain of interactions was probably initiated by anthropogenic changes in the offshore oceanic ecosystem.
منابع مشابه
Effects of Apex Consumers Cascade Dynamically across Trophic Levels
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عنوان ژورنال:
- Science
دوره 282 5388 شماره
صفحات -
تاریخ انتشار 1998