Good news for Yellow-legged Gulls (Larus michahellis): a new study shows that the use of GPS tags has no significant effect on the reproductive success of individuals fitted with them. This study also confirms the reliability of the data collected for this species
Any intervention on a wild species can have an impact. This is especially true for on-board equipment such as GPS beacons, which are being deployed with increasing frequency on a large number of individuals and species. It is therefore crucial to assess the potential effects of such equipment: from an ethical point of view, this ensures that they are as minimal as possible, as well as guaranteeing the validity of the results obtained. Indeed, if an individual’s behavior is significantly modified by the equipment installed, the data collected will not be representative of the usual behavior of individuals in the population.
In 2023, Langlois et al. highlighted the negative impact of GPS “backpack” beacons on the reproduction of Great Black-backed Gulls (Larus marinus) in a Scottish colony. The same type of beacon being used, with the same method of attachment, in the Tour du Valat’s monitoring projects for Yellow-legged Gulls (Larus michahellis), the same analyses were therefore reproduced in 4 colonies monitored on the French and Catalan Mediterranean coast.Charly Souc, PhD student in the team responsible for analyzing data from the beacons, was able to demonstrate that, in this species, no significant effect of this equipment on the reproduction of tagged individuals could be demonstrated in any of the 4 colonies. These results are reassuring: they tend to show that the impact of such equipment can differ from one species to another, and therefore encourage us to reproduce this type of analysis for other species. It will also be important to investigate other possible medium- and long-term impacts on survival and reproduction.
Source :
Souc, C., Leray, C., Blanchon, T., Dagonet, T., Vittecoq, M., Ramos, R. and McCoy, K.D. (2024), No detrimental effects of wing-harnessed GPS devices on the breeding performance of Yellow legged Gulls (Larus michahellis): A multi-colony evaluation. Ibis. https://doi.org/10.1111/ibi.13338
