Monday, July 11, 2011

Shrinking Rabbit Population Affects Iberian Lynx Population

European rabbit

The Donana National Park in south-western Spain is famous for being the last refuge of the endangered Iberian lynx. This shy and beautiful cat has suffered several several types of threats, including shortage of its favorite prey: rabbits. The rabbit population had suddenly dropped during the late 1980s as a result of viral hemorrhagic disease (VHD). This disease not only affected the lynx, but also other carnivore species such as the fox, the Egyptian mongoose, the genet, and the badger. A team of Argentinian and Spanish researchers investigated this case, and found that the downfall in rabbit population has mostly affected the lynx which could not hunt any other prey.

The red fox; one of few carnivores to adapt following the collapse in rabbit population.

The team's data has shown that the biggest drops in rabbit consumption were observed among the badger and fox populations, from 71.8 % to 26.2 % and 20.2 % to 9.8 %. But despite the drop in rabbit population, the fox had substituted the animals for other prey like birds, small mammals, and even ungulates (in form of carrion). According to Dr. Pablo Ferreras of the Research Institute on Cynegetic Resources (IREC), the fox population had benefited during the last five following the disease's arrival. He further added that the population of genets and mongooses also sustained due to maintenance in rabbit consumption.

The Iberian lynx; a flagship species that prefers only rabbits and no other prey species.

The lynx, on the other hand, never substituted the rabbits for any other prey. Dr. Ferreras pointed out that the rabbit constitutes to 75 % of the cat's diet, making it a specialist. The researchers also pointed out that the disease changed the lynx's social system. That is, it became less territorial, and in the case of females, their home range size expanded. This meant that that the number of sub-adults stayed in areas where they were born. Based on the findings, the researchers said that the current rabbit populations are still feeling the aftershocks from the collapse. They also said that further predation is affecting the population recovery. This could lead to shortage in rabbit population, which would jeopardize the lynx population.

I'm very much shocked to see how the Iberian lynx population has been affected by the shortage of prey. These cats seem to prefer mostly rabbits, and not any other prey. I feel that some serious action is required in order to help reboost the rabbit population before it plummets down any further. According to the researchers, the recommendation is management measures with the options of habitat improvement and restocking programs. I believe that another solution would be reintroduce more rabbits from elsewhere in Europe where they were introduced. These cute and cuddly creatures were introduced as an exotic species in places like England. While the VHD has proved to be effective in Australia where the species is an exotic pest, in Spain it is a completely different story. I think, in order to reintroduce the species back, a useful tip would be to test individuals for the virus. At the same time, research on developing a vaccine should be undertaken. The population of the rabbits in Spain is at stake and so is the lynx. Without any action, both species' populations in Donana would be lost forever.

View article here     

No comments:

Post a Comment