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Chris Trosen

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Prairie ecosystems and the grassland birds that rely on them for habitat may be particularly vulnerable to rapid changes in climate. Extensive portions of prairie have already been lost due to agriculture and urbanization, and as a result grassland birds have declined more than any other bird group in the last four decades. Now, climate change could exacerbate existing threats to these birds as temperatures in certain prairie ecosystems are expected to rise and extreme weather events, such as drought, could become more common. The goal of this project was to develop a framework to identify demographic sensitivities and assess the vulnerability of grassland bird species to future climate change. To do so, the researchers...
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To ensure habitat restoration efforts are targeted towards areas maximizing monarch population growth, it is important to understand the effects of landscape heterogeneity on monarch occurrence in habitat patches (i.e. grasslands with milkweeds). Over two summers (2018-2019), monarch adults, larvae, and eggs were surveyed at sixty grassland sites in Wisconsin varying in patch size and landscape context. Milkweed density and floral richness were also estimated to characterize local patch quality. Results suggest that optimal sites for monarch habitat restoration are within landscapes with less surrounding habitat and that high milkweed density and floral richness should be conservation goals.
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