Do agricultural sites provide high quality habitat for declining grassland songbirds?

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Grassland birds are in steep decline throughout North America and these declines are caused mainly byregional habitat loss and degradation as a result of agricultural intensification. A key question is how canhabitat quality be improved in agricultural landscapes to benefit declining grassland birds? Few studies havetested how different agricultural habitats impact the breeding success. There is also an urgent need to studyhabitat selection of grassland songbirds in agricultural landscapes, both during and after nesting, to betterunderstand how habitat quality affects breeding females. Prior studies have been hampered by the high expenseand difficulty of radio-tracking songbirds. We are studying Savannah Sparrows (Passerculus sandwichensis), adeclining species in Canada and the U.S, near Guelph, ON. In 2016, funded by ENGAGE, we monitored 10nests from intensive agricultural sites and 26 from natural sites and found that nesting success was similar inthese vastly different habitats. Adult body mass was also not significantly different between agricultural andnon-agricultural sites for both males and females. We are also using innovative new technology (MOTUSautomated telemetry array) to remotely track the dispersal and habitat selection of post-breeding adults overtens of kilometers and up until the point of fall migration. Birds radiotagged with uniquely coded Nanotags areautomatically detected when they fly within 5-10 km of any of the dozens of receiver towers in southwesternOntario. In 2016 we tagged 14 adults in agricultural sites and 18 in natural sites; movement data will beavailable in Feb 2017 for analysis. We will use GIS analysis of landscape features to monitor post-breedinghabitat selection, and test if nesting habitat carries over to affect timing of fall migration. By continuing thisstudy in 2017, to increase sample sizes and to test for between-year effects (2016 was a drought year) ourresearch will identify which agricultural habitats can best sustain declining populations of grassland birds. Thisis expected to lead to management recommendations for farmers.