Article

Okavango's crocs given a fighting chance

Karin Theron

Dr. Alison Leslie, crocodile researcher from the University of Stellenbosch.

The crocodiles of the Okavango swamps in Botswana have just been given another fighting chance, following the first step in the approval of a nesting sanctuary.

This follows recent talks between Dr. Alison Leslie, head of the Department of Conservation Ecology (Faculty of Agricultural and Forestry Sciences) at Stellenbosch University and leader of a research team who are studying the crocodile population of the Okavango swamps, and the Minister of Environment, Wildlife and Tourism, MP Mr. Onkokame K Mokaila in Gabarone.

"I told the Minister that we desperately need a nesting sanctuary as the number of nesting crocodiles has decreased by one third over the past 15 years," she explains.

Dr. Leslie and her team have been working relentlessly over the past three years to convince the local population of the value of the crocodiles, not only for the sake of their environment, but also as a means of job creation. They also work closely with the three crocodile farms in Botswana to ensure sustainable utilisation of the crocodiles.

Nile crocodiles of the Okavango have been heavily exploited by hide hunters since 1957, and more recently by crocodile ranchers who are allowed to take eggs from the wild based on a quota system. This form of utilization can be sustainable, however, the required 5% return of juveniles back into the system has never been enforced. My research team's counts show that only 3% of the crocodile population are currently hatchlings. This means that there will soon be only a small number of breeding adults.

"As the crocodiles are a keystone species, this will not only impact on tourism, but on the whole Okavango ecosystem. Crocodiles are at the top of the food chain and therefore play a huge role in the overall health of the entire ecosystem. They for instance limit the abundance of prey, control fish populations and they provide essential forms of nutrients for primary production of food, through the by-products given off from their metabolic functioning. If this source of nutrients is removed, it will naturally reduce the source of food for the other members of the food chain."

Dr. Leslie explains that they did a GIS study on the area which showed that most of the Okavango panhandle is suitable habitat for nesting. They added a disturbance map which shows human interference to that and came to the shocking conclusion that approximately 60% of the crocodile's suitable nesting habitat is no longer available!

Of the approximate 50 nests that are laid each year only 20 or so are found within the proposed sanctuary area. Although this sounds like a little, Dr. Leslie is positive that this initiative, together with well regulated crocodile farming, will indeed save the crocs of the swamps.

It is envisioned that this sanctuary will be protected by the Department of Wildlife and National Parks' anti poaching unit, the Botswana Defense force in the area and the nearby communities, all under the watchful eye of Dr. Leslie's team whose research camp is in the delta.

More information:

For more information, contact Karin Theron at vinofino@mweb.co.za 

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