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Difference between revisions of "Crabeater seal"
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===Diet=== | ===Diet=== | ||
[[File:Crabeater teeth.png|thumb|left|Graphic showing crabeater teeth]] | [[File:Crabeater teeth.png|thumb|left|Graphic showing crabeater teeth]] | ||
Despite its name, the crabeater seal does not feed on crabs (the few crab species in its range are mostly found in very deep water). Rather, it is a specialist predator on [[Antarctic krill]] (''Euphausia superba''), which comprise over 90% of the diet. Their high abundance is a testament to the extreme success of Antarctic krill, the single species with the greatest biomass on the planet. There is little seasonality in their prey preference, but they may target adult and male krill. Other prey items include cephalopods and diverse Antarctic fish species. Although the crabeater seal is sympatric with the other Antarctic seal species (Weddell, Ross and leopard seals), the specialization on krill minimizes interspecific food competition. Among krill-feeding whales, only [[blue | Despite its name, the crabeater seal does not feed on crabs (the few crab species in its range are mostly found in very deep water). Rather, it is a specialist predator on [[Antarctic krill]] (''Euphausia superba''), which comprise over 90% of the diet. Their high abundance is a testament to the extreme success of Antarctic krill, the single species with the greatest biomass on the planet. There is little seasonality in their prey preference, but they may target adult and male krill. Other prey items include cephalopods and diverse Antarctic fish species. Although the crabeater seal is sympatric with the other Antarctic seal species (Weddell, Ross and leopard seals), the specialization on krill minimizes interspecific food competition. Among krill-feeding whales, only [[blue whale]]s (''Balaenoptera musculus'') and [[minke whale]]s (''B. acutorostrata'') extend their range as far south as the [[pack ice]] where the crabeater seals are most frequent. | ||
While no reliable historical population estimates have been done, population models suggest crabeater seal populations may have increased at rates up to 9% a year in the 20th century, due to the removal of large baleen whales (especially the blue whale) during the period of [[whaling|industrial whaling]] and the subsequent explosion in krill biomass and removal of important competitive forces. | While no reliable historical population estimates have been done, population models suggest crabeater seal populations may have increased at rates up to 9% a year in the 20th century, due to the removal of large baleen whales (especially the blue whale) during the period of [[whaling|industrial whaling]] and the subsequent explosion in krill biomass and removal of important competitive forces. | ||