Black-legged kittiwakes as messengers of Atlantification in the Arctic

• Published in: Scientific reports Vol. 8; no. 1; pp. 1178 - 11
• Main Authors: Vihtakari, Mikko, Welcker, Jorg, Moe, Børge, Chastel, Olivier, Tartu, Sabrina, Hop, Haakon, Bech, Claus, Descamps, Sébastien, Gabrielsen, Geir Wing
• Format: Journal Article
• Language: English
• Published: England Nature Publishing Group 19.01.2018; Nature Publishing Group UK
• Subjects: Ecosystem ecology; Environmental Sciences; Food chains; Food webs; Juveniles; Marine ecosystems; Marine organisms; Matematikk og naturvitenskap: 400; Mathematics and natural scienses: 400; Phenology; Population dynamics; Prey; Sea ice; Species; VDP; Zoologiske og botaniske fag: 480; Zoology and botany: 480; Zooplankton; Arctic region
• ISSN: 2045-2322; 2045-2322
• DOI: 10.1038/s41598-017-19118-8

Climate warming is rapidly altering marine ecosystems towards a more temperate state on the European side of the Arctic. However, this "Atlantification" has rarely been confirmed, as long-term datasets on Arctic marine organisms are scarce. We present a 19-year time series (1982-2016) of diet samples from black-legged kittiwakes as an indicator of the changes in a high Arctic marine ecosystem (Kongsfjorden, Svalbard). Our results highlight a shift from Arctic prey dominance until 2006 to a more mixed diet with high contribution of Atlantic fishes. Capelin, an Atlantic species, dominated the diet composition in 2007, marking a shift in the food web. The occurrence of polar cod, a key Arctic fish species, positively correlated with sea ice index, whereas Atlantic species demonstrated the opposite correlation indicating that the diet shift was likely connected with recent climate warming. Kittiwakes, which gather available fish and zooplankton near the sea surface to feed their chicks, can act as messengers of ecosystem change. Changes in their diet reveal that the Kongsfjord system has drifted in an Atlantic direction over the last decade.