When I started writing my project proposal, almost everyone warned me about the difficulty of catching adult pelicans, which is absolutely necessary to carry out the research I was intending. Some suggestions included sneaking on to the birds while breeding on Dassen Island, others to use cannon nets, or monofilament gill nets, or nylon loops… But almost none of them have been tested and proved successful before. So I confronted the first of many big challenges of my PhD.

Dr.Allain Crivelli provided me with a key contact: Dr. Tommy King, who had used modified leg traps to catch American White Pelicans, Great Blue Herons and other large wading birds in North America (King et al. 1998). The modifications consist of the substitution of the factory springs for weaker ones and the addition of extra padding on the edge of the claws. To prevent the birds from flying with the traps, these are connected to a long extensible cord, which is then fixed to the ground.

Setting up the traps on the pig farm

When I first looked at the traps I was concerned about using them on the birds; they looked vicious, and everyone's comments pointed out the harm that they could cause to the bird's legs. But after an initial accident and then a lot of courage, I tried them on myself, triggering the claws on my own hands. After checking that no bones were broken, I was ready to test them on the pelicans.

Doug and Marius holding the first pelican trapped with the leg traps

And they worked fabulously! The first day we caught only one pelican and two Kelp Gulls, which were released unharmed. The second time we were ready for it: we captured 5 adult pelicans. And I have to say they are big birds!

The trapped pelicans were in general quite collaborative, at least when held by 3 people. That was a long day for Doug Harebottle, Marius Wheeler and I but we managed to ring them, take genetic and microbiological samples, record the weight, take morphmetric measurements and check on their moult. It was a very successful day and we were aware that we are some of the few people in the world that have trapped and ringed adult Great White Pelicans!!

We plan to acquire more traps, which will allow capturing more birds simultaneously. Soon we will test them in St Lucia Wetland Park (KwaZulu-Natal). This will be done in the framework of Marine and Coastal Management project, lead by Rob Crawford. The aim is to capture at least two Great White Pelicans and attach satellite transmitters to them. This will allow us to know in detail their movements in the region. At least another two birds will be tracked with this method in the Western Cape later on this year.

Pelicans breeding on Dassen Island                                      Photo L.Underhill

References used in this article:

• King, D. T., J. D. Paulson, D. J. Leblang, and K. Bruce. 1998. Two capture techniques for American White Pelicans and Great Blue Herons. Colonial Waterbirds 21:258-260.