PARENT SESSION
Poster Session 13: Landscape Ecology / Geomorphology
Tuesday, August 9, 5:00 PM - 6:30 PM, Exhibit Hall 220 A-E, Level 2, Palais des congrès de Montréal
Factors determining avian species richness in Atlantic Canada.
Mailhiot, Joshua*,1, Silva, Marina1, Sanchez, Javier1, 1 University of Prince Edward Island, Charlottetown, Prince Edward Island, Canada
ABSTRACT- Very few studies have used a regional approach to investigate the factors that determine avian species richness in Canada. We investigated the effects of body mass, land cover features, and other abiotic factors on the patterns of species richness of birds breeding on Prince Edward Island (PEI), Canada. Data on species richness were obtained from the Breeding Bird Atlas of the Maritime Provinces, while information on body size and other factors were collected from published literature. Land cover features were calculated using the 1990 PEI Forest Inventory and ArcView GIS. Variation in species richness across PEI was measured by dividing the entire island into 98 equal area cells (10 x 10 km). Using various statistical tools, we developed four different models with different theoretical and practical purposes. With the exception of body mass, other factors known to determine species richness at larger spatial scales explained small, and often non-significant amounts of the variation in species richness. Overall the models showed that the range of body mass spanned by species within assemblages at each sampling cell was the major determinant (53% variance explained) of avian species richness on PEI, suggesting that factors such as energetics and/or resource partitioning may be responsible for this pattern. There were also significant relationships between the range of body mass spanned by avian assemblages and several land use covers. However, land use covers explained up to 25% of the variation in avian species richness on PEI after excluding body mass from the model. The best multivaritate model explained 78% of the variation in avian species richness, and included body mass range, and the physical dimensions of agricultural fields and other human infrastructures. Overall our findings show that avian species richness on PEI is not only affected by energetics, but it is particularly influenced by land-use activities such as agriculture.
Key words: Species Richness, Body Size, Aves, Land-use