Use of an INLA Latent Gaussian Modeling Approach to Assess Bird Population Changes Due to the Development of Offshore Wind Farms

Abstract

The utilization of marine renewable energies such as offshore wind farming leads to globally expanding human activities in marine habitats. While knowledge on the responses to offshore wind farms and associated shipping traffic is accumulating now at a fast pace, it becomes important to assess the population impacts on species affected by those activities. In the North Sea, the protected diver species Red-throated Diver (Gavia stellata) and Black-throated Diver (Gavia arctica) widely avoid offshore wind farms. We used an explicit spatio-temporal Bayesian model to get a robust estimate of the diver population during the spring season between 2001 and 2018, based on a set of aerial surveys from long-term monitoring programs within the German North Sea. Despite the erection of 20 offshore wind farms in the study area and marked responses of divers to wind farms, model results indicated that there was no population decline, and overall numbers fluctuated around 16,600 individuals, with average annual 95% CI ranging between 13,400 and 21,360 individuals. Although, avoidance behavior due to wind farm development led to a more narrowly focused spatial distribution of the birds centered in the persistent high concentration zone in the Eastern German Bight Special Protection Area, the results provide no indication of negative fitness consequences on these long-lived species. However, more research is needed on habitat use and food availability in this regard.

Annual movements of a migratory seabird—the NW European red-throated diver (Gavia stellata)—reveals high individual repeatability but low migratory connectivity

“…6) and statistical analyses of individual repeatability (Table A1) show an individual consistent site use in consecutive years, considered over a broad scale. Combined with the findings of Mendel et al (2019) and Vilela et al (2021), these data suggest that red-throated divers are somewhat flexible to change sites at small scales, but may have limited flexibility to change sites at large scales in response to large-scale habitat loss.…”

“…If habitat selection is driven by a macro-selection, it could be that habitat change has an effect on a smaller spatial scale and displacement is a process happening at smaller scales. However, in this context, results from studies on red-throated diver distributions and displacement effects in the eastern German Bight showed that red-throated divers remained in the general area, but shifted their distribution and congregated outside disturbed areas (Mendel et al 2019;Vilela et al 2021). Mendel et al (2019) analysed long-term datasets of aerial and ship based surveys, whereas Vilela et al (2021) analysed long-term datasets of aerial surveys.…”

“…However, in this context, results from studies on red-throated diver distributions and displacement effects in the eastern German Bight showed that red-throated divers remained in the general area, but shifted their distribution and congregated outside disturbed areas (Mendel et al 2019;Vilela et al 2021). Mendel et al (2019) analysed long-term datasets of aerial and ship based surveys, whereas Vilela et al (2021) analysed long-term datasets of aerial surveys. However, no population decline was observed (Vilela et al 2021).…”

“…Mendel et al (2019) analysed long-term datasets of aerial and ship based surveys, whereas Vilela et al (2021) analysed long-term datasets of aerial surveys. However, no population decline was observed (Vilela et al 2021). Considering this, our data based on the visualised tracks, single home ranges (Fig.…”

“…In this study, we analysed the migratory behaviour of a seabird species, the red-throated diver (Gavia stellata), that is increasingly influenced by human activities in one of their most important winter and spring staging areas in Europe, the German Bight (eastern North Sea) (Garthe et al 2007(Garthe et al , 2015Dierschke et al 2012;Burger et al 2019;Mendel et al 2019;Heinänen et al 2020). In this winter population, strong avoidance of offshore wind farm areas was observed (Mendel et al 2019;Heinänen et al 2020;Vilela et al 2021) but, so far, no decline in wintering population numbers of this long-lived species (Vilela et al 2021). Red-throated divers are listed in Annex II of the Bern Convention, Annex I of the EU Birds Directive and as critically endangered on the HELCOM (Helsinki Commission) convention (BirdLife International 2022).…”