1. Annual Precipitation and Bird Population Caitlin Gorden, Jamie Jefferson, James Nooyen Jr. University of Wisconsin-Platteville The Christmas Bird Count started on Christmas day in 1900 to prevent widespread shooting of birds, and promote simply counting them. The dataset goes back to 1900 and it evolved into a countrywide movement. One count made within a predetermined 15 mile diameter area over one day. All counts take place between December 14 th and January 5 th. Counts rely on volunteers to contribute data, so some error must be taken into account regarding volunteer effort. Data collected each year by the CBC has been used by a number of researchers for their publications. Their findings have been used to spur conservation efforts, track long term health of birds, and follow migration patterns. Riveredge Nature Center, located in Saukville, Wisconsin, has been collecting data for the CBC since 1969. With these data sources, we checked to see if there was a correlation between precipitation levels and populations of select finch species, specifically the Purple Finch (Carpodacus purpureus), Pine Siskin (Carduelis pinus), and American Goldfinch (Spinus tristis). We hypothesize that there will be a significant correlation between yearly precipitation levels and population sizes of C. purpureus, C. pinus, and S. tristis within the dataset provided by the Saukville Riveredge Nature Center from 1969-2011. We would like to thank all contributors and volunteers of the Audubon Christmas Bird Count that have spent numerous hours collecting the data that made this research possible. Thanks to the Riveredge Nature Center for providing access to their CBC data. A special thanks to our professor, Dr. Huebschman, as well as our class members who took the time to give us feedback. Introduction Conclusions There was no significant correlation found between precipitation levels and populations of specific finch species in the Saukville area. The lack of a significant correlation could be due to other factors or a combination of factors affecting finch population sizes. Link, Sauer, and Niven used CBC data in combination with weather data to look at population changes of Northern Bobwhites from 1964 to 2004. (Link, Sauer & Niven, 2011) Root found that precipitation is frequently associated with the range limits of bark gleaners and seed eaters on a continent-wide scale. (Root, 1988) The same methodologies can be applied to test other possible correlations between precipitation levels and other bird species. This could also be used to correlate specific bird species to other bird species, i.e. hawk to finch populations, etc. References History of the christmas bird count. (2013). Retrieved from http://birds.audubon.org/history-christmas-bird-count Link, W. A., Sauer, J. R., & Niven, D. K. (2011). Combining breeding bird survey and christmas bird count data to evaluate seasonal components of population change in northern bobwhite. Journal of Wildlife Management, 75(8), 44-51. doi: http://dx.doi.org/10.2193/2007-299 National Oceanic and Atmospheric Administration, National Environmental Satellite, Data and Information Service. (1969-2011). Noaa climatological data annual summary wisconsin. Retrieved from website: http://www.ncdc.noaa.gov/IPS/cd/cd.html?_page=0&jsessionid=B2 5FC89C7EAF642ED67F6596715FF570&state=WI&_target1=Next > Root, T. (1988). Environmental factors associated with avian distributional boundaries. Journal of Biogeography, 15(3), 489-505. Retrieved from http://www.jstor.org/stable/2845278 Methodology Results Birds Used: Purple Finch (C. purpureus) Pine Siskin(C. pinus) American Goldfinch (S. tristis ) We used these species because they are in the same family and have data all the way back to the beginning of the count. They also fluctuate from year to year, providing a window to determine if the fluctuations are correlated with precipitation. They eat mainly seeds with weeds, berries, and sometimes insects as supplements, which are affected by precipitation. Annual precipitation data was taken from the NOAA Data Climatic Data Center for Port Washington, WI as it is the closest data collection center to the Riveredge Nature Center. To standardize the bird count data, we adjusted for volunteer effort (birds per party hour= total number of birds seen/ total number of party hours in the field). Then a regressional analysis was run using Microsoft Excel to linearize the correlation between the selected finch populations and annual precipitation in order to determine if there is a positive or negative relationship between the two variables. Fig. 1 – C. purpureus adjusted counts plotted against annual precipitation (cm). No significant correlation found to exist between bird population and annual precipitation. Trend line included. Each point represents one year of data between 1969 and 2011. Fig. 3 – S. tristis adjusted counts plotted against annual precipitation (cm). No significant correlation found to exist between bird population and annual precipitation. Trend line included. Each point represents one year of data between 1969 and 2011. Fig. 2 – C. pinus adjusted counts plotted against annual precipitation (cm). No significant correlation found to exist between bird population and annual precipitation. Trend line included. Each point represents one year of data between 1969 and 2011. Table 1 – The r 2 indicates the correlation strength between annual precipitation and finch populations. C. purpureusC. pinusS. tristis r 2 -value0.006080.002010.06766 Acknowledgements