The influence of weather and habitat fragmentation on plant and insect phenology, arrival times and breeding success of boreal birds

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Breeding areas for resident and migrant birds in North America are becoming increasingly fragmented by human use and birds must also cope with changing climate.  Climate warming is predicted to be most intense at high latitudes, hence, boreal birds may be most affected.  Since forest microclimate is affected by patch size and surrounding forest cover, harsher weather conditions and lower amounts insect food in smaller patches may reduce survival of winter residents.  However, in spring, fragments may warm up earlier, have earlier plant and insect phenology and more insects, hence medium sized patches may be of high quality in spring and summer.  These interactions between fragmentation, weather and microclimate and phenology and the impacts of these on population persistence in fragmented landscapes have not been well studied.  The main objectives of this proposal are to: 1. Determine the influence of patch size and surrounding forest cover on micro-climate, plant phenology, insect phenology and abundance in winter and summer. 2. Relate these factors to winter survival and body condition and to breeding season food conditions and reproductive success of resident birds (chickadees, nuthatches, woodpeckers). 3. Relate these factors to arrival times, territory choice and reproductive success of migrants. 4. Determine the relationship of spring temperature and extreme weather events on sex and age ratios of migrant birds arriving at banding stations in the northern parts of the breeding range.