PARENT SESSION
Poster Session 28: Avian Ecology
Thursday, August 11, 5:00 PM - 6:30 PM, Exhibit Hall 220 A-E, Level 2, Palais des congrès de Montréal

Predicting habitat use patterns of fragmentation-sensitive forest birds at multiple scales in southwestern Quebec (Canada).

Carignan, Vincent^{1, 2, 3}, Drapeau, Pierre^{1, 2, 3, 4}, ¹ Université du Québec à Montréal, Montréal, Québec, Canada² Groupe de recherche en écologie forestière interuniversitaire, Montréal, Québec, Canada³ Chaire d'étude sur les écosystèmes urbains, Montréal, Québec, Canada⁴ Chaire CRSNG-UQAT-UQAM en aménagement forestier durable, Rouyn-Noranda, Québec, Canada

ABSTRACT- The southwestern portion of the Province of Quebec (Canada) consists of highly modified agricultural and urban landscapes, where forest cover has been estimated to be less than 50%. During the summers of 2002 and 2003, we sampled the avifauna associated with residual mature maple forests in urban (< 10% forest), agricultural (20-60% forest), and forested landscapes (> 75% forest) using point-counts (two 20-min visits) and conspecific playbacks (two visits of 2 min per target species; n = 346). Measures of local, patch and landscape variables were collected for each site. Linear regressions revealed that our target species (Black-throated Blue Warbler, Ovenbird, Wood Thrush, Scarlet Tanager, White-breasted Nuthatch, and Pileated Woodpecker) reacted at least to two of the three scales we investigated. Local variables and landscape configuration variables explained the greatest proportion of the variance. Among the most often retained explanatory variables (all positively correlated with abundance) were: perimeter/area ratio, spatial configuration of the woodlots within 1 or 5 km of the site, distance to the closest woodlot of 1000 ha or more (presumed source) and mean woodlot area within 1 or 5 km of the site. Despite the elevated fragmentation level observed in certain parts of our study area, the region retains enough forest and this forest is distributed in such a way that most sensitive species are able to persist in the landscape. Further investigations are underway to determine the reproductive success of these species and their dependence on large source woodlots.

Key words: birds, fragmentation, multiple-scales, Quebec