![]() Merely one or two incidents doesn’t make either of them predator of the other. ![]() Killer whales must eat polar bears at regular intervals (which they don’t!) just like they eat fish or turtles only in this way white bears can become the orca’s diet.Apart from that polar bears never become the regular part of the killer whale’s diet. The polar bear cubs can fall prey to the killer whales (when their mother is not around) which made biologists to believe that orcas eat polar bears.Besides, none of them has any natural predator in the arctic. Still scientists do not recognize the fact of polar bears getting killed by orcas because both marine mammals seem to share many behavioral traits.Polar bears can never become the diet of orcas but certain unreported incidents in the past showed that orcas do kill polar bears. At this speed they feed on medium-sized preys to as large as minke whales. Orcas are able to reach the maximum speed of 25 miles per hour which qualify them as one of the fastest marine mammals.Journal of Animal Ecology © 2017 British Ecological Society. Pusa hispida Ursus maritimus Svalbard prey-shifting sea-ice declines spatial overlap. Shifts in ecological interactions are likely to become more widespread in many ecosystems as both predators and prey respond to changing environmental conditions induced by global warming, highlighting the importance of multi-species studies. Our results indicate that sea-ice declines have impacted the degree of spatial overlap and hence the strength of the predator-prey relationship between polar bears and ringed seals, with consequences for the wider Arctic marine and terrestrial ecosystems. Polar bears now move greater distances daily and spend more time close to ground-nesting bird colonies, where bear predation can have substantial local effects. However, ringed seals did not alter their association with glacier fronts during summer, leading to a major decrease in spatial overlap values between these species in Svalbard's coastal areas. Following the sea-ice reduction, polar bears spent the same amount of time close to tidal glacier fronts in the spring but less time in these areas during the summer and autumn. We used linear mixed-effects models to evaluate the association of these species to environmental features and an approach based on Time Spent in Area to investigate changes in spatial overlap between the two species. We attached biotelemetry devices to ringed seals (n = 60, both sexes) and polar bears (n = 67, all females) before (2002-2004) and after (2010-2013) a sudden decline in sea ice in Svalbard. We also investigated whether the spatial overlap between polar bears and their traditionally most important prey, ringed seals (Pusa hispida), has been affected by the sea-ice decline, as polar bears are dependent on a sea-ice platform for hunting seals. We investigated how the movement and space use patterns of polar bears (Ursus maritimus) in coastal areas in Svalbard, Norway, have been altered by a sudden decline in sea ice that occurred in 2006. ![]() Understanding these alterations can help improve predictive capacity and inform management efforts designed to mitigate against negative impacts. Climate change is impacting different species at different rates, leading to alterations in biological interactions with ramifications for wider ecosystem functioning. ![]()
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