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

北美的留鸟和候鸟的繁殖区由于人类的使用而变得越来越分散，鸟类也必须科普不断变化的气候。 据预测，气候变暖在高纬度地区最为强烈，因此，北方鸟类可能受到的影响最大。 由于森林小气候受斑块大小和周围森林覆盖的影响，恶劣的天气条件和较小斑块中昆虫食物量的减少可能会减少冬季居民的生存。 然而，在春季，碎片可能升温较早，植物和昆虫物候较早，昆虫较多，因此中等大小的斑块在春季和夏季可能具有较高的质量。 碎片化，天气和小气候和物候之间的相互作用，这些对人口的持续性在破碎化景观的影响还没有得到很好的研究。 本提案的主要目标是：1.确定斑块大小和周围森林覆盖对小气候、植物物候、昆虫物候和冬夏丰富度的影响。2.将这些因素与冬季生存和身体状况以及繁殖季节食物条件和常驻鸟类（山雀，nuthatches，啄木鸟）的繁殖成功联系起来。3.将这些因素与移徙者的抵达时间、领土选择和生殖成功联系起来。4.确定春季温度和极端天气事件对到达繁殖范围北方部分环志站的候鸟性别和年龄比的关系。

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.