The results of our surveys carried out during the Hungarian meadow viper LIFE project have shown that the common buzzard is one of the most important birds of prey hunting for the Hungarian meadow viper. In order to better understand the territorial use of buzzards and the predation pressure on Hungarian meadow viper populations, we tagged GPS trackers on three birds in the Upper Kiskunság, near Kunpeszér. The devices are used to monitor the movements of some of the buzzards nesting next to viper habitats.
To place these small devices on the birds, we captured the birds using the eagle owl model and nets. The operation, which seems simpler than described, was carried out by members of the Raptor Specialist Group of MME BirdLife Hungary.
In addition to the tagging, the birds were ringed and given the names Heni, Pascal and Hannibal for future identification. But how do the GPS transmitters work?
The GPS transmitter weighing just 18 grams, is attached to the bird’s back by teflon straps, like a small backpack. It doesn’t hinder movement, and because the transmitter weighs no more than 2% of the bird’s body weight, its weight doesn’t affect the bird’s life. The tracking device transmits the geographical coordinates provided by the GPS locator to a computer system via the mobile phone network, which also provides a map of the bird’s movements.
The data from the trackers, which were installed in the summer and have now been in operation for six months, show that the hunting area of the buzzards overlaps with the habitats of the vipers. After nesting, we examined the food remains accumulated in the nests, which showed that one of the buzzards had certainly caught a Hungarian meadow viper for its nestlings.
Our tagged birds are providing information that will help us to explore how landscape-habitat characteristics influence the foraging and habitat choice of the buzzards.
We thank Béla Kalocsa, Dr Anna Enikő Tamás, Dr Balázs Koleszár and Márton Árvay for their contribution to the successful capture and marking of buzzards.