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
Ovenbird abundance and housing density changes in Massachusetts from 1970 to 2000: a metapopulation modeling perspective.
Wunnicke, Aaron*,1, Lepczyk, Christopher1, Radeloff, Volker1, Pidgeon, Anna1, Flather, Curtis2, Hammer, Roger3, 1 Department of Forest Ecology and Management, Madison, WI, USA2 USDA Forest Service, Fort Collins, CO, USA3 Department of Rural Sociology, Madison, WI, USA
ABSTRACT- Habitat loss and fragmentation are major factors responsible for the decline of many Neotropical migrant birds. One driver of habitat loss and fragmentation is housing growth. Housing growth may be especially important in forested landscapes where it can occur below the canopy and thus escape the detection of remotely sensed land cover maps. To investigate how housing development may affect forest dwelling Neotropical migrant birds we investigated the relationship between housing growth and ovenbird (Seiurus aurocapillus) abundance in Massachusetts. We compared estimates of ovenbird relative abundance and housing density for each decade from 1970 to 2000 using the North American Breeding Bird Survey (BBS) and the decennial Census. We found a significant negative relationship between ovenbird abundance and housing density within 400 m of the BBS routes (adj. r2 = 0.54). The relationship resulted in a simple linear regression model that was used in RAMAS GIS to extrapolate habitat suitability maps of the entire state for 1970, 1980, 1990, and 2000. As housing density increased over time, ovenbird populations were fragmented. Specifically, we found that large areas of western Massachusetts may constitute fairly contiguous habitat that may serve as a source of breeding birds for populations in more isolated patches in the eastern part of the state. We manipulated several RAMAS parameters (fecundity, carrying capacity, and dispersal distance) to determine ovenbird metapopulation sensitivity. Overall, we found a strong decline in suitable habitat in Massachusetts and identified potential areas that are important for maintaining long-term viability of ovenbird populations in the state.
Key words: Neotropical, metapopulation, habitat fragmentation, housing density