French bears suffering from lack of females
The population of brown bears in France is now so small that the species might become extinct in the near future, according a study, but introducing new females to the region could help reverse the decline.world Updated: Oct 28, 2009 08:40 IST
The population of brown bears in France is now so small that the species might become extinct in the near future, according a study, but introducing new females to the region could help reverse the decline.
The research, published in online journal PLoS ONE, suggests the bear population is suffering from having a greater number of males and that adding females would not just boost its numbers but help tackle some of the reasons behind the decline.
"Our results suggest that having a viable bear population in France requires further translocations. In particular, male bears need more females," said Guillaume Chapron of the Swedish University of Agricultural Sciences, who led the study.
The brown bear population in France disappeared from most of the country during the 20th century and now survives only in two separate communities in the Pyrenees mountain range.
The central population, which was created by a previous relocation of bears from Slovenia, has more females and is growing, while the western population, which is in decline, is more male-dominated.
The researchers looked at data collected between 1993 and 2005 and found that while adult survival rates in the two groups were similarly high, the western population had much lower reproductive success than the central population.
The team said their findings rule out the previously proposed role humans in the bear population's decline, instead suggesting it was likely due to inbreeding or because the group's male bias was leading to infanticide -- when males kill unrelated cubs so females want to reproduce again.
These causes could be addressed by adding new females, said Chapron and his colleagues, and the French bear population could recover if enough were introduced.
Their findings counter previous suggestions that relocations should not take place until the cause of population decline has been reversed, showing that in some cases relocation itself could actually help tackle the reasons behind falling numbers.