Date of Defense
Date of Graduation
Our world is changing more than many individuals could imagine. Climate change is not a hoax. Comprehensive empirical records of changes since 1900 in local, regional, and global temperature clearly indicate that Earth is warming more rapidly than ever in recorded history. In response, some bird species are already shifting, both phenologically (timing) and geographically. However, the majority of birds are not shifting or not shifting fast enough, and this is resulting in population declines. A much smaller number of studies suggest that mammals are also shifting phenologically and geographically.
If we do not alter our current behaviors soon, Earth will warm in excess of 4.5oC by 2100. Such warming is likely to result in the extinction of many species of birds and mammals, and substantial population declines for many more. The most vulnerable species will be those that live at high latitudes, high altitudes, and on islands.
Overexploitation, the overuse of wildlife and plant species by people for food, medicinal and personal use, also affects a wide range of birds and mammals. 345 species of birds and 250 species of mammals threatened due to overexploitation. 14% of the world’s bird and 22% of the world’s mammals are exploited for either consumption or medicinal uses; of these, 23% of bird species are threatened and 36% of mammal species are threatened.
Although climate change and overexploitation are formidable threats, there are solutions for both. If we act quickly to replace fossil fuels with carbon-free energy sources, several of which are already viable alternatives, we can avoid many adverse effects on birds and mammals. Overexploitation can be minimized by strengthening existing international regulations. The first step for all solutions is to generate the desire to implement them.
Denny, Rachel, "The Effects of Climate Change and Overexploitation on Birds and Mammals: Phenological shifts, range shifts, and population changes" (2012). Honors Theses. 2357.
Honors Thesis-Open Access