Climate Change May Drastically Impact Antarctic Fur Seals (VIDEO)

It turns out that climate change may be impacting Antarctic fur seals far more than expected. A genetic analysis of these animals in addition to decades of monitoring has shown that these seals have significantly changed due to shifts in food availability associated with climate conditions.

Climate change is expected to affect species that range from single-celled organisms to mammals. Understanding exactly what changes that these species might undergo, though, is an important part of learning about how shifting conditions might alter an ecosystem. That's why scientists decided to examine fur seals a bit more closely with data as far back as 1981.

"Compared with 20 years ago, we can see that female fur seals are now born with a lower weight, those that survive and return to breed tend to be the bigger ones and they have their first pup later in life than they used to," said Jaume Forcada from the British Antarctic Survey in a news release. "Such changes are typically associated with food stress."

Food, in this case, happens to be Antarctic krill. These small crustaceans are the basis for the food web in these cold reaches. Yet environmental variation driven by the climate can impact local atmospheric, sea ice and oceanographic conditions. The adverse climatic conditions are associated with low krill availability which, in turn, can affect seals.

In fact, the researchers found that females that survived to motherhood were more likely to be more "heterozygous," which is when an individual possesses a higher level of genetic variation. This is associated with a higher level of fitness in many species.

"We found that, over the last two decades, the proportion of breeding females that are highly heterozygous has increased, as these individuals are more likely to survive the changing conditions," said Joe Hoffman, co-author of the new paper, in a news release. "Strong selection by the environment can drive rapid evolution. However, in this case the seals do not appear to be evolving because surviving females do not pass their high heterozygosity on to their offspring."

The findings reveal that climate has a huge role in terms of seal population health. In fact, populations of fur seals continue to decline. If this continues, steps may need to be taken in order to protect these mammals.

The findings are published in the journal Nature.

Want to learn more? Check out the video below, courtesy of YouTube.