Wednesday, May 23, 2012

First catch your vulture!

Preparations are underway to catch five Lappet-faced Vultures in Botswana, to fit them with satellite transmitters to track their movements throughout the country. There are many ways to catch a vulture, but apparently they are all difficult! But catching the bird is the first unavoidable step in this project being undertaken by BirdLife Botswana in conjunction with the Denver Zoo and CKGR Research team. Traditionally, vultures in Africa have been caught successfully using a cannon-net – a cannon which fires a large net over a group of vultures. However, the conventional cannon-net is not a viable option any longer due to restrictions on the possession and movement of the explosives used to power the device. However, colleagues at the Denver Zoo have managed to find a similar device, called a Net-Blaster, which works on compressed air to fire the net. This item is shown below.
The vultures will need to be attracted to a bait within range of the Net Blaster, which can then be triggered remotely to fire the net over the birds. It all sounds very simple! We don’t want to rely on a single method, so we have a back-up option too. Colleagues in the region have done a review of vulture capture methods, excluding those utilising explosives. Top of the list is a walk-in cage trap which has been used successfully in South Africa and Namibia. We are in the process of constructing a portable version which we intend to deploy during June. The photo below shows what it will look like when complete:
In theory, the vultures enter the cage to feed on the bait; the curtain is then closed from a remote, concealed site, and the birds are trapped inside. While not wanting to tempt fate, there is a high possibility that one or both of these methods will be successful! Both however need two additional ingredients – patience and perseverance! The next post on this site will report on our experience with actually catching our target species, and fitting the satellite transmitters. Pete Hancock