Soaring strategy investigation of cinereous vulture (Aegypius monachus) by sailplane

SEYHUN DURMUS; GÖKSEL KESKIN

doi:10.56093/ijans.v90i10.111311

Authors

SEYHUN DURMUS Edremit School of Civil Aviation, Balikesir University, Balikesir, Turkey
GÖKSEL KESKIN Faculty of Science and Letters, Eskisehir Osmangazi University, Eskisehir, Turkey

https://doi.org/10.56093/ijans.v90i10.111311

Keywords:

Aegypius monachus, Avian flight, Cinereous vulture, Flight behaviour, Thermal soaring

Abstract

Soaring has great importance to large and heavy terrestrial birds because they can gain altitude without using power in this way. The cinereous vultures were near threatened species in the world, so it was hard to observe them while circling in thermals or slope soaring. Although there were enough works on conservation and breeding biology of those birds, there was not any study on the soaring technique. In this work, cinereous vulture observed and tracked in thermal columns using a glider to figure out whether the turn performance of the cinereous vulture matched well with other vulture species. Finding the pros and cons of tracking and observation of the cinereous vulture's turn performance in a thermal by a glider was another objective of the study. The results indicated that the cinereous vulture can complete the thermal circling with a narrower radius which provides advantages to stay in the strongest part of the thermal.

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