July 23, 2010 | 2
Giant panda habitats are too fragmented and need to be reconnected in order for the endangered animals to maintain their genetic diversity, a new study shows.
The study, conducted by researchers from the Chinese Academy of Sciences and the China Wildlife Conservation Association, both in Beijing, was published July 23 in the open-access journal BMC Genetics.
The giant panda (Ailuropoda melanoleuca) used to live in relative isolation from humans, but the 20th century brought villages, towns, roads, dams and other projects that now prevent pocket panda populations from visiting each other and exchanging genetic materials (in other words, breeding).
The researchers visited four patches of habitat in the Xiaoxiangling and Daxiangling mountains, with a mean distance of 76 kilometers between each patch. A total of 192 fecal samples were collected and revealed 53 unique genotypes. This, the researchers say, demonstrates signs of fragmentation within the panda population.
One of the study’s co-authors, Fuwen Wei from the Chinese Academy of Sciences, said in a prepared statement: "These results suggest that gene flow will be enhanced if the connectivity between the currently fragmented bamboo forests is increased. This may be of importance to conservation efforts as gene flow is one of the most important factors for maintaining genetic diversity within a species and counteracting the negative effects of habitat fragmentation."
How do we get the pandas to reconnect? The researchers say that bamboo forests need to be replanted, which would give the giant pandas enough food to wander and mix their populations. Doing so will "restore population viability of the giant panda in these regions," the authors wrote in the conclusion to their paper.
No one knows exactly how many giant pandas remain in the wild, especially after the devastating earthquakes that hit Sichuan province in 2008. Next year, China will embark on its fourth national survey of giant pandas, the last of which was conducted between 1998 and 2002. As Wei discussed in a June article published in Cosmos, the survey will use some of the same molecular techniques (DNA fingerprinting) he employed in this new study to count the animals, and the survey aims to come up with a better assessment of the pandas’ population in the wild.