Herps in the News--Hawaiian Skink Declared Extinct

 I was looking at some articles online, and came across a couple about a skink that is no longer in Hawaii.  The copper striped blue-tailed skink (Emoia impar) was declared extinct in the Hawaiian Islands earlier this month by the U.S. Geological Survey.  The skink was a native, and was at one time a common animal on the islands.  E. impar can still be found on some other islands in the Pacific, however it has not been seen in over 40 years in Hawaii.  Last seen on the coast of Kauai, the copper striped blue-tailed skink is described in the article as having “polished scales, with a sky-blue tail.”  Surveys had been conducted throughout the Hawaiian archipelago from 1988 to 2008, and the skink was never found.

The copper striped blue-tailed skink
Picture is from reptilechannel.com

USGS Biologist Robert Fisher, who has done research on the copper striped blue-tailed skink, discussed that there is some evidence that the skink may have become extinct because of the introduction of the big-headed ant (Pheidole megacephala). Fisher believes the ants were preying on the skinks, which could be useful information for other herps that are at risk in the Pacific islands.

Fisher also discusses in the articles that the extinction of animals living on any particular island are in similar situations, such as habitat loss due to urbanization and the native species being displaced by invasive species that are accidentally or purposely introduced.  For the copper striped blue-tailed skink, it is possible that invasive species in Hawaii can increase competition and predation on the natives.  E. impar may have also been affected by what Fisher explains as “cryptic extinction.”  In this situation, there is another species that the skink could be confused with, making it less noticeable to scientists when their population is in danger.  As a result, the animal can go extinct for years without scientists realizing it.  The other disadvantage for the skinks is that they’re small and cautious animals, making them less noticeable and human intervention is less likely to occur.  Other animals in the Hawaiian Islands, especially birds, are easy for humans to see and hear, and so scientists have more information on their populations.

Marcia McNutt, a director of USGS, commented on the loss of E. impar and stated “No other landscape in these United States has been more impacted by extinction events and species invasions in historic times than the Hawaiian Islands, with as yet unknown long-term cascading consequences to the ecosystem.”  It’s unfortunate that Hawaii is having environmental problems, especially with the exotic-looking animals like E. impar.

Here are the two articles:

http://www.reptilechannel.com/reptile-news/2012/03/21/hawaiian-skink-now-extinct.aspx

http://www.kitv.com/USGS-Skink-Now-Extinct-In-Hawaii/-/8906042/9657796/-/9jw8kh/-/index.html