Archive for October, 2010

Satellite tracking of the Short-toed Eagle migration

Wednesday, October 20th, 2010 Posted in Migrations, Reviews | No Comments »

Nic, the first satellite tracked eagle in Italy, with a Microwave Telemetry 45-gram solar GPS PTT-100 transmitter that was affixed to the back using a tubular Teflon ribbon harness - photo by Ugo Mellone

On our webpages we repeatedly raised the question of studying migration of birds of prey using satellite telemetry. This method has pluses and minuses compared to traditional ringing, colour marking etc. The review makes an attempt to reveal, at least partly, potential opportunities of the satellite telemetry on the example of studying migrations of the Short-toed Eagle.

Some researchers and birdwatchers oppose the direct installation of satellite transmitters on birds basing on ethic reasons. Their main argument: until the absence of negative impacts is proved the method cannot be used in researches. However, it is not an easy task to receive such proofs. It would require control observations of certain types of transmitters and certain bird species and further processing of results with the use of statistical analysis to minimize as much as possible the effect of random factors. Firstly, the sample of birds should be large enough for such processing, which means installation of a lot of transmitters, secondly we must conduct parallel observations of the control bird group without transmitters attached. But exactly the latter is impossible since nowadays there are no other effective methods designed for long-term tracking of birds in their natural environment. In addition, installation and monitoring of even a single transmitter is still fairly expensive, not to mention their dozens. This fact puts restrictions on the use of this method in favour of its opponents.

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