Behavioral responses to offshore windfarms during migration of a declining shorebird species revealed by GPS-telemetry

• DOI: 10.1016/j.jenvman.2023.118131
• Publication Date: 2023-05-19T21:12:27Z
• Authors: Philipp Schwemmer; Moritz Mercker; Karena Haecker; Helmut Kruckenberg; Steffen Kämpfer; Pierrick Bocher; Jérôme Fort; Frédéric Jiguet; Samantha Franks; Jaanus Elts; Riho Marja; Markus Piha; Pierre Rousseau; Rebecca Pederson; Heinz Düttmann; Thomas Fartmann; Stefan Garthe
• Keywords: Baltic sea; Tern

EU member countries and the UK are currently installing numerous offshore windfarms (OWFs) in Baltic North Seas to achieve decarbonization of their energy systems. OWFs may have adverse effects on birds; however, estimates collision risks barrier for migratory species notably lacking, but essential inform marine spatial planning. We therefore compiled an international dataset consisting 259 migration tracks 143 Global Positioning System-tagged Eurasian curlews (Numenius arquata arquata) from seven European recorded over 6 years, assess individual response behaviors when approaching at two different scales (i.e. up 3.5 km 30 distance). Generalized additive mixed models revealed a significant small-scale increase flight altitudes, which was strongest 0-500 m OWF more pronounced during autumn than spring, due higher proportions time spent migrating rotor level. Furthermore, four integrated step selection consistently detected horizontal avoidance responses about 70% curlews, approximately 450 OWFs. No distinct, large-scale were observed plane, although they could possibly been confounded by changes altitudes close land. Overall, 28.8% crossed least once migration. Flight within overlapped with level high degree (50%) significantly lesser extent spring (18.5%). Approximately 15.8% 5.8% entire curlew population estimated be increased risk migration, respectively. Our data clearly show strong responses, likely reduce risk, simultaneously highlight substantial effect species. Although alterations paths seem moderate respect overall route, there is urgent need quantify respective energetic costs, given massive ongoing construction both sea areas.