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Grizzly bears, black bears, wolves, coyotes, cougars/ mountain lions,bobcats, wolverines, lynx, foxes, fishers and martens are the suite of carnivores that originally inhabited North America after the Pleistocene extinctions. This site invites research, commentary, point/counterpoint on that suite of native animals (predator and prey) that inhabited The Americas circa 1500-at the initial point of European exploration and subsequent colonization. Landscape ecology, journal accounts of explorers and frontiersmen, genetic evaluations of museum animals, peer reviewed 20th and 21st century research on various aspects of our "Wild America" as well as subjective commentary from expert and layman alike. All of the above being revealed and discussed with the underlying goal of one day seeing our Continent rewilded.....Where big enough swaths of open space exist with connective corridors to other large forest, meadow, mountain, valley, prairie, desert and chaparral wildlands.....Thereby enabling all of our historic fauna, including man, to live in a sustainable and healthy environment. - Blogger Rick

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Tuesday, December 6, 2016

Will Orca Whales(Killer Whales) ultimately replace Polar Bears as "King of the Arctic" in Hudson Bay as climate change eliminates the far north Ice Packs that the Bears require to hunt seals from?


Orcas may replace polar bears as top predator. Here's where

Sunday, December 4, 2016, 4:31 PM - Researchers say melting sea ice in Hudson Bay continues to stir a dramatic shift in the food chain, with killer whales eating their way to the top of the predator list.
"We are seeing a lot more killer whale activity in Hudson Bay and they are a top predator," Steven Ferguson, researcher with Fisheries and Oceans Canada and the University of Manitoba told CBC. "They are really a magnificent, interesting predator - highly efficient."
According to Ferguson, sea ice irritates the dorsal fin of an orca. However, because ice is melting earlier each year,the predators are spending more time searching for food in the bay.

"They appear to be eating other whales and seals and, I would imagine, if we lose our sea ice they will replace polar bears as that top predator," the researcher told CBC.
Ultimately, this could have a major impact on other species.
Each summer, nearly 60,000 beluga whales migrate from the Hudson Strait to the southwestern coast of the bay to feed and mate. This is one of the largest concentrations of Belugas in the world. However, Ferguson says they are at risk.

"They are food for killer whales and we've had a few instances where we have recorded attacks by killer whales on the beluga population," he told the news agency. "It probably happens more often than we know because it's not an easy thing to observe.

What do killer whales eat in the Arctic?

January 29, 2012
BioMed Central

Killer whales (Orcinus orca) are the top marine predator, wherever they are found, and seem to eat everything from schools of small fish to large baleen whales, over twice their own size. The increase in hunting territories available to killer whales in the Arctic due to climate change and melting sea ice could seriously affect the marine ecosystem balance. New research published in BioMed Central's re-launched open access journal Aquatic Biosystems has combined scientific observations with Canadian Inuit traditional knowledge to determine killer whale behaviour and diet in the Arctic.

Orca have been studied extensively in the northeast Pacific ocean, where resident killer whales eat fish, but migrating whales eat marine mammals. Five separate ecotypes in the Antarctic have been identified, each preferring a different type of food, and similar patterns have been found in the Atlantic, tropical Pacific, and Indian oceans. However, little is known about Arctic killer whale prey preference or behaviour.
Traditional Ecological Knowledge (TEK) is increasingly being used to supplement scientific observations. Researchers from Manitoba visited 11 Canadian Nunavut Inuit communities and collated information from over 100 interviews with hunters and elders.

The Inuit reported that killer whales would 'eat whatever they can catch', mainly other marine mammals including seals (ringed, harp, bearded, and hooded) and whales (narwhal, beluga and bowhead). However there was no indication that Arctic killer whales ate fish. Only seven of the interviewees suggested that killer whales ate fish, but none of them had ever seen it themselves.
The type of reported prey varied between areas. Most incidents of killer whales eating bowhead whales occurred in Foxe Basin and narwhal predation was more frequent around Baffin Island. Inuit were also able to describe first-hand how killer whales hunted, including several reports of how killer whales co-operated to kill the much larger bowhead. During the hunt some whales were seen holding the bowhead's flippers or tail, others covering its blowhole, and others biting or ramming to cause internal damage. Occasionally dead bowheads, with bite marks and internal injuries but with very little eaten, are found by locals.
'Aarlirijuk', the fear of killer whales, influenced prey behaviour with smaller mammals seeking refuge in shallow waters or on shore and larger prey running away, diving deep, or attempting to hide among the ice. Even narwhal, which are capable of stabbing a killer whale with their tusks (although this is likely to result in the deaths of both animals), will run to shallow waters and wait until the whales give up.

Orcas will come right up on beachfront land to grab a seal meal

Killer whales are seasonal visitors to the area and have recently started colonising Hudson Bay (possibly due to loss of summer sea ice with global warming). Local communities are reliant on the very species that the orcas like to eat. Dr Steven Ferguson from the University of Manitoba who led this research commented, "Utilising local knowledge through TEK will help scientists understand the effects of global warming and loss of sea ice on Arctic species and improve collaborative conservation efforts in conjunction with local communities."

Story Source:
Materials provided by BioMed CentralNote: Content may be edited for style and length.

Journal Reference:
  1. Steven H Ferguson, Jeff W Higdon and Kristin H Westdal, Aquatic Biosystems. Prey items and predation behavior of killer whales (Orcinus orca) in Nunavut, Canada based on Inuit hunter interviewsAquatic Biosystems, 2012 (in press)

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