It\u2019s well known that polar bears are the top predator in the Arctic, each one killing a seal every three to five days.<\/p>\n
What hasn\u2019t been well understood is just how much carrion the estimated 26,000 polar bears leave behind once they finish dining on seal blubber. It turns out that with each polar bear abandoning about 300 kilograms of biomass every year, the total amounts to more than seven million kilograms, says the University of Alberta\u2019s polar bear expert\u00a0Andrew Derocher<\/a> \u2014 enough to feed a wide range of scavengers.<\/p>\n \u201cIt\u2019s a staggering amount,\u201d which has an enormous impact on the ecosystem, says the professor in the Department of Biological Sciences<\/a>. At least a third of a seal carcass is normally left for scavengers such as Arctic foxes, gulls, ravens and even other polar bears. Snowy owls, wolves and grizzly bears have also been observed consuming the leftovers.<\/p>\n \u201cThere are so many different species, depending on where you are, that exploit polar bear kills,\u201d says Derocher.<\/p>\n Derocher and his international collaborators \u2014 most of whom are former U of A doctoral students \u2014 published their\u00a0latest study on polar bear carrion in the journal Oikos<\/a> in October. Much of the research was funded by the San Diego Zoo Wildlife Alliance<\/a>, which has just provided an additional $100,000 per year for three years for further study.<\/p>\n \u201cPeople think that if polar bears disappear from the ecosystem because of climate change, it will just mean there will be more seals. But this paper shows the linkages across the ecosystem,\u201d notes Derocher, adding that in regions where polar bear populations are declining, about 323,000 kg of carrion have been lost every year.<\/p>\n Because polar bears pull seals from the water and leave them on the ice, many scavengers have no other way of gaining access to the food. And as the ice melts due to climate change, it could become harder for some animals to reach the bears\u2019 leftovers. Carrion can act as a buffer for scavengers when food resources run low.<\/p>\n Derocher\u2019s team examined observational and anecdotal data of scavenging in the Arctic dating back to the 1930s, calculating how many seals polar bears consume each year, and how many calories seal blubber provides.<\/p>\n \u201cWe\u2019ve had lots of birds, and Arctic foxes are the primary scavengers,\u201d says Derocher of his observations in the field. \u201cThey\u2019ll actually follow polar bears for long distances.\u201d<\/p>\n Derocher also says that if a polar bear kills a seal, it\u2019s common for other bears to smell it and come to see if there\u2019s a free meal.<\/p>\n \u201cWhen we\u2019re near a seal kill out on the sea ice, we\u2019re on high alert. It\u2019s like the dinner bell has rung and everybody in the area is coming for a meal.\u201d<\/p>\n","protected":false},"excerpt":{"rendered":"It\u2019s well known that polar bears are the top predator in the Arctic, each one killing a seal…\n","protected":false},"author":2,"featured_media":233984,"comment_status":"","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[6],"tags":[127033,5328,127034,701,3184,85,46,127036,54698,127035,125],"class_list":{"0":"post-233983","1":"post","2":"type-post","3":"status-publish","4":"format-standard","5":"has-post-thumbnail","7":"category-technology","8":"tag-andrew-derocher","9":"tag-arctic","10":"tag-biological-science","11":"tag-biology","12":"tag-ecology","13":"tag-il","14":"tag-israel","15":"tag-northern-ecosystems","16":"tag-polar-bears","17":"tag-scavengers","18":"tag-technology"},"_links":{"self":[{"href":"https:\/\/www.newsbeep.com\/il\/wp-json\/wp\/v2\/posts\/233983","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.newsbeep.com\/il\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.newsbeep.com\/il\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/il\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/il\/wp-json\/wp\/v2\/comments?post=233983"}],"version-history":[{"count":0,"href":"https:\/\/www.newsbeep.com\/il\/wp-json\/wp\/v2\/posts\/233983\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/il\/wp-json\/wp\/v2\/media\/233984"}],"wp:attachment":[{"href":"https:\/\/www.newsbeep.com\/il\/wp-json\/wp\/v2\/media?parent=233983"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.newsbeep.com\/il\/wp-json\/wp\/v2\/categories?post=233983"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.newsbeep.com\/il\/wp-json\/wp\/v2\/tags?post=233983"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}