Changes in the population size of three gull species in protected areas managedby Verein Jordsand e. V.
Eine explorative Analyse
DOI:
https://doi.org/10.21248/corax.v26.52Abstract
Verein Jordsand e. V. has been surveying breeding pair populations of three gull species in the protected areas managed by the trust for many years. Using population figures from 2013–2022, the present work analyses statistical trends for breeding pairs of Herring Gulls Larus argentatus, Lesser Black-backed Gulls Larus fuscus, and Great Black-backed Gulls Larus marinus. Considering all protected areas together, there is no indication that Herring Gull population change substantially. However, in individual protected areas, Herring Gull populations show relatively large year-to-year variability. Similar fluctuations for individual protected areas were observed for Lesser Black-backed Gull populations. In contrast with Herring Gulls however, the total number of breeding pairs of Lesser Black-backed Gulls has decreased overall as well. While the populations of Great Black-backed Gulls in the managed protected areas are generally lower, it accounts for roughly one third of the gull’s entire German population of around 100 pairs. Within the managed protected areas, a slight statistical tendency towards an increase over time is evident. The present analysis contrasts the trends for these three gull species in the managed protected areas with the species’ overall population trends in Germany and Europe as reported in relevant literature. It also discusses possible reasons for their population changes.
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