A Five-Year Survey of Native Bee Diversity and Abundance in North Georgia

Commercial fruit, nut, and vegetable agriculture are dependent on bees for pollination services.  In the following study, native bee abundance and diversity was investigated from 2010-2014 in Georgia apple orchards.  The survey occurred over the entire growing season (March-September) with special emphasis on the apple bloom. Over 20,000 bees were collected using pan traps, vane traps, malaise traps, and sweep netting. 2010 was a traditional apple bloom dominated by Andrena species.  In 2011 and 2012, the apple bloom occurred 2 to 4 weeks early.  During these blooms, much lower Andrena species were present; however, greater abundances of Osmia species and other non-Andrena bees were documented. In 2013, the apple bloom was 2-3 weeks later than the traditional bloom.  Interestingly, overall diversity and abundance were much higher than in the previous years.  In 2014, a traditional apple bloom took place, and the Andrena species once again dominated the samples. In order to use native pollinators successfully in commercial agriculture, we will need to gain a better understanding of the abundance, diversity, emergence times, and pollination behaviors of the native bee species.