Effects of Harbour and Ship Channel Construction on Breeding Seabirds

Bird population changes were studied during the construction of the new Vuosaari Harbour in 2001–2011 (Helsinki, Finland, N60°14.52' E25°9.07'). Part of the monitoring programme was to determine the possible impacts of harbour and ship channel construction on breeding seabird populations. The study revealed that the population trends of most species showed no substantial difference between islets close to harbour and channel and more distant reference islet. A Black-headed Gull colony was destroyed by landfill but that was deliberately and with permission. The trends of Ruddy Turnstone and Great Black-backed Gull populations were more negative in near than in distant islets. In the surrounding archipelago, the Barnacle Goose, Mew Gull and Common Black-headed Gull clearly increased during the study years. The European Herring Gull decreased distinctly, which was probably caused by the removal of individuals from the rubbish dumps around Helsinki. There were some differences between the restricted-and open-access islands. The population of Herring Gull was higher and the decline stronger in the restricted areas, while the Common Ringed Plover population simultaneously increased.