The surge of hunting that depleted many polar bear populations in the 20th century is largely under control. But just as the species has been recovering from that threat, global warming is creating new pressures through the loss of summer sea ice and other impacts on the bears? preferred maritime habitat.
Recent DNA analysis has shown that polar bears are a far older species than was thought even a few years ago, and they clearly are adaptable and resilient. But it?s also clear that some populations will have a very hard time in coming decades. What should people do in such cases?
I?ve written previously about a valuable proposal by some scientists to start planning a long-term conservation strategy focused on regions of the Arctic where sea ice is expected to persist even with substantial warming.
But a new policy paper in Conservation Letters, ?Rapid ecosystem change and polar bear conservation,? proposes a series?of steps that could kick in a lot sooner ? including everything from relocation programs to feeding of starving bears or in some cases ?intentional population reduction? ? a k a culling.?There?s a solid look at the paper in Yale Environment 360.
The relocation and feeding seemed a bit of an overreach compared to what has been done for other species, particularly predators, when they?re in extremis. So
I reached out to the lead authors, including?Andrew Derocher, a professor of biology at the University of Alberta in Edmonton, Canada, who (along with at least two other authors of the paper) is an adviser to Polar Bears International, a private group campaigning to conserve the Arctic predator.
Here?s my query (slightly adjusted):
I?ve got to say that the proposal strikes me as an overreaction, particularly when you compare the responses to what humans do for other endangered species.
What other wild species ? particularly predators ? are fed to fend off starvation?
There are relocation programs for nonpredators (Asian rhinos in Nepal) and some predators to new habitats (mountain lions to Florida), But in those cases it?s to reintroduce something to depopulated habitat, not save individuals from starvation on their home range. (Again there may be other examples; happy to hear of them.)
Here?s the thoughtful and thorough reply from Derocher, who?s also the author of ?Polar Bears: A Complete Guide to Their Biology and Behavior?:
I don?t think the public views polar bears the same way as most other endangered species and this is one of the reasons that we laid out some of the options. ?If there is a species where we may make extraordinary efforts, polar bears likely fit right up there with giant pandas and California condors. ?The paper isn?t a prescription for what should be done but rather what could be done. ?
This is a policy perspective paper and what is clearly lacking is policy and plans about what will happen when we see a sudden change in a polar bear population. ?Our analyses of sea ice suggest such events will happen and likely much sooner than expected in Hudson Bay. The worst time to make policy and management plans is in the middle of a crisis. ?If you consider the response that is generated by a whale stranding event in the U.S., you have a sense of what is possible. ?We could see an impending starvation event in polar bears and there is no established response plan anywhere. ?Some wildlife managers I?ve spoken too are worried about exactly such events: they know the problem will land on their desks and the pressure from the top will be intense.
We lay out the whole spectrum of options in the paper: do nothing, euthanize the starving, right through to feeding bears. ?Europeans keep their brown bear populations alive in many countries by feeding them. ?Black bears in Washington State are fed to reduce damage on trees (e.g., Ziegltrum. 2006, ?Cost-effectiveness of the black bear supplemental feeding program in western Washington,? Wildlife Society Bulletin). We can feed black bears to protect trees so I find it hard to believe there won?t be a major push to feed polar bears for at least part of the year to either keep populations from crashing in the early stages of collapse or even in the longer term to artificially support a semi-wild population. ?If I?m not mistaken, California condors are given clean carcasses as a supplemental food source. ?I can foresee huge pressure on politicians and wildlife managers to intervene. ?The ?do nothing? option isn?t likely acceptable to many but for others, it will be the preferred option. We need to have these discussions in advance and nothing happens in the north without consultation as it is often mandated to consult with communities.
All of us involved in polar bear science have received many e-mails with well-intentioned input from the public about what we should be doing. The usual options are making plastic ?ice? floes but feeding polar bears is a common theme. ?Shipping in ?overabundant? seals from Newfoundland and Labrador is a frequent suggestion. I was particularly struck by a truck driver who contacted me with the idea of shipping all the dead wildlife he sees along the side of the roads he travels. ?Moving polar bears is another common theme ? sometimes north but often to the Antarctic (the latter obviously not an option). This paper was intended to generate discussion and hopefully, some planning. The Arctic is changing incredibly fast but it seems that, in Canada at least, this is simply viewed as an economic opportunity (more mining, more drilling, more shipping, and new fisheries).
There are some bright spots ? the recent involvement of WWF to assist a community in deterring bears away from town. Similar projects in eastern Russia are helping out but these are NGO driven program with limited resources and these sorts of actions will be required across the Arctic over time.
Ultimately, conservation biology is a forward-looking practice. ?For polar bears, we have many managers stuck in the past. Many politicians and upper level bureaucrats are ignoring the issues. ?We?re not dealing with greenhouse gases so we will be dealing with starving polar bears and disappearing populations.
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