Male Orangutans using landscape corridors

Orangutans, native to Indonesia and Malaysia, have been reduced to a population of an estimated 6,600 and to a patch of habitat in the northern tip of Sumatra due to habitat loss and degradation.  Habitat fragmentation is associated with increased isolation of patches and reduction of total area, which decreases population size and increases extinction rate.

One of the solutions proposed and implemented to increase movement between patches are landscape corridors, as we have discussed in lecture and section.  The topic of whether or not the corridors are actually effective or worth the monetary cost has been controversial.

 It seems that in this specific case, the corridors have proved to play a positive role in connecting the small patches in that they have been facilitating gene flow and movement within the Orangutans.  The study found that the females tend to settle in the areas where they are closest to their mothers and that it is the males who travel, across rivers or mountains, in search for a mate. 

Dr. Alexander Nater of the University of Zurich stated that the corridors give the Orangutans the chance to act like a large population. This case gives some hope to other isolated populations of species however, it's hard to know if other species would be as apt to using the corridors as the Orangutans.  The article ended on this note, emphasizing the need for protection of these corridors. The corridors aren't ideal, but they are effective so far in helping facilitating the continuation of genetic diversity of the Orangutans.  At this point, when there is so little of the Orangutan habitat left and little options remaining to keep them from entering the extinction vortex, the corridors have made a positive step forward.

The article can be found here on the New York Times.