Can common forest bird species tolerate disturbances in neighbouring areas? A case study of the Vuosaari Harbour construction in southern Finland

Abstract

We studied the population growth and expansion of Barnacle Goose (Branta leucopsis) in Helsinki archipelago, southern Finland. Barnacle Goose breeding was first recorded in Helsinki in 1989. During our study 1996–2013 the number of nesting geese increased from 24 to 740 pairs.We analyzed the role of protected islands in the population growth, and the factors behind differences in growth rates. Our study data consisted of 104 islands. Of these, 29 are protected from private recreational activity (nature reserve ormilitary areas) and were established prior to the start of our study.We predicted that protected areas would have a positive impact on Barnacle Goose population growth. In part of the study period (2002–2013) the population growth in our study area was much steeper in protected islands compared to islands with open access.Results indicate that early breeders likeBarnacleGeese do not benefit from island protection probably because the recreational use of the islands is scant early in the spring.