Investigating sources, transport, accumulation and effects of persistent contaminants in urban environments using a top predator as indicator

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Building on recent research, I propose to develop a program to investigate the ecotoxicology of priority contaminants in top predators inhabiting urbanized and neighboring semi-rural environments. Many ecologically important Canadian landscapes, such as the Fraser and Okanagan regions of southern British Columbia are being rapidly transformed into a matrix of urban and residual rual lands. Such landscapes continue as habitat for breeding of birds of prey and as wintering areas for latitudinal and altitudinal migrants. This proposal focuses on using the Cooper's hawk, Accipter cooperii, as a primary bioindicator of sources, fate, transport and effects of persistent organic contaminants (POPs) in such systems. POPs of recent concern such as brominated flame retardants and perfluorinated compounds appear to originate from use and disposal of commercial products in urban areas, and likely move through and contaminate the environment in the form of fine dust and aerosols. I hypothesize that top predators are exposed to such pollutants through their diet of birds and small mammals, which in turn accumulate contaminants via food, dermal and inhalation exposure and the increased need to preen feathers and fur in more environments with increased atmospheric loadings of dust and aerosols. Birds of prey, particularly in urbanized environments, are also exposed to and poisoned by second generation anticoagulant rodenticides. Currently, the sources and consequences of such exposure are poorly understood in bird-eating raptors such as the Coooper's hawk. Traditional methods will be used to locate nesting territories and measure reproduction. Nests will be visited and as needed blood and unhatched eggs collected for exposure determination. Technologies such as remote video, advanced telemetry techniques such as GIS data loggers and stable isotopes will be used to determine diet and food web relations. Effects will be assessed using biomarkers. Population genetics will be investigated using microsatellite DNA markers. Results will be communicated to risk assessors and regulators in federal and provincial governments.