Climate change and habitat loss are two major factors effecting animal and plant species. Changes in presence and abundance of bird species effect ecosystems as well as the ecotourism industry. Christmas Bird Counts, sponsored by the National Audubon Society, are one-day events in which all birds are counted in a 7.5 mile radius circle. Counts take place across North America from December 14 – January 5. The Flour Bluff Christmas Bird Count is one of the top counts in North America in terms of number of species seen and has been conducted annually since 1963. We restricted our analysis to species seen on 44 or more of the 48 years the count has been conducted. We compared local trends to continent-wide trends and evaluated changes in land use in the count circle since 1963 in an effort to determine if changes in presence and abundance are due to climate change or changes in land use patterns.
Results/Conclusions
Anecdotal evidence from participants was that several species were declining. However, we found only 15 out of 89 species have shown a decreasing trend. Surprisingly, 34 species show an increasing trend. Two species were declining but are now stable and another two species have shown a sharp increase then a decrease. The remaining 53 species exhibit no apparent trend, though some have high variability. Not all species in our circle follow continent-wide trends. For example, the American White Pelican and Eared Grebe show no continent-wide trend, but in our circle, the American White Pelican is increasing and the Eared Grebe is decreasing. However, some species, such as the Eastern Meadowlark and the Vesper Sparrow, do follow continent-wide trends. Although climate change may be involved in the decline for these two species, decline of grassland habitat is obviously important in this trend both on the continent-wide and local level. We attempted to see if climate change and land use patterns explain the trends for the other species.