Can we save polar bears by moving them to Antarctica?
Answered by Scott Schliebe, scientist emeritus with the U.S. Fish & Wildlife Service. "Although it may seem an obvious solution, the risks outweigh the benefits."
Q. I am writing concerning the plight of polar bears due to sea-ice loss in the Arctic. It occurs to me that one possible way out, that I have not so far seen considered, is simply to move a sufficient number of polar bears to a promising spot on the Antarctic ice pack where the species might get a fresh start. Some areas seem to abound with seals. I can imagine there would problems in transporting them, but I have never seen consideration of this simple approach.
A. This question comes up from time to time from well-intending individuals. While intuitively the initial concept may seem to have merit, a closer examination indicates that it is not a simple solution and includes a great deal of downside risk. I believe it would be unwise to translocate or introduce polar bears into Antarctica for a number of reasons, some of which follow.
Such an introduction counters the well accepted principles of natural bio-diversity.
History offers many examples of species introductions resulting in an imbalance within the natural system: for example, the mongoose to Hawaii, the brown tree snake to Guam, foxes to the Aleutian Islands, and various invasive plant and aquatic species. A number of web sites include more detailed info. One is www.gisp.org, which says:
"Invasive non-native species can harm individual native species or even entire ecosystems, and thus also impact those who depend on natural systems for important resources and products. Unlike other kinds of pollution, these 'biological pollutants' can actually increase in abundance over time and force out native species – by competing with them (for space, water, or food), by eating the native species, spreading new diseases, or so altering the habitat that the native species can no longer survive. In fact, the impacts of non-native species are now recognized as second only to habitat alteration as a factor in the decline and extinction of our American flora and fauna."
- In general, polar bear predation could result in unanticipated and catastrophic consequences to prey species, particularly naive prey species. As an example, penguins would be easy prey for polar bears. Predation of penguins, especially on their breeding grounds, could devastate their populations.
- Potential disease pathogens could be either introduced from the Arctic by the bears or be present in Antarctica and threaten the bears.
- It is unlikely that all habitat and nutritional needs for polar bears would be met through all seasons.
- Even if translocations were successful, which is unlikely and would not occur at some cost to other components of the ecosystem, are we merely setting the stage for later concerns if bears are threatened by Antarctic ice loss? Although the indications of sea ice loss are not as striking as with the arctic region, there are signs that climate change is affecting Antarctic sea ice as well. While it is highly unlikely that transplants that would not create imbalances within the natural system could be achieved, would bears face other habitat threats from climate change and loss of habitat in Antarctica at a later time?
- This concept violates a number of national and international statutes or treaties. Many countries are going to great lengths to restrict the import or introduction of exotics into very sensitive ecosystems. Because of the simple nature of the Arctic/Antarctic ecosystems, it is easy to imagine these being thrown out of balance with a new apical predator.