2005 BES Annual Meeting Presentation and Poster Abstracts
Movement patterns and patch fidelity of bees and butterflies in urban parks and gardens
Kevin M. Cox and Gail A. Langellotto
Abstract: Although insect species richness typically decreases with urbanization, butterflies and bumblebees are nonetheless regularly observed within urban habitats. Flowering plants are numerous in certain city environs (e.g. parks and gardens) and many butterflies and bumblebees may be able to exploit these localized resources for nectar and pollen. However, in order for individual insects to utilize nectar and pollen sources within urban parks and gardens, they must be able to effectively disperse through the concrete streets, lots, and buildings that characterize urban areas. An understanding of how insects move through the urban matrix and the degree to which they utilize small, fragmented urban habitat patches may be valuable to conservation planning initiatives in cities and suburbs. In the Summer of 2005 over 600 individual Pieris rapae butterflies and 230 Bombus impatiens bumblebee individuals were marked in 12 community gardens and parks in the Bronx and East Harlem in New York City. Gardens and parks varied in size, floral area and distance from each other and were revisited after marking to determine degree of patch fidelity and interpatch movement for both taxa. For each garden, patch fidelity was investigated as a function of patch size and floral area. In addition, 70 P. rapae and 40 B. impatiens individuals were translocated from gardens into the urban matrix to determine movement patterns and degree of return. B. impatiens showed greater patch fidelity and less interpatch movement than P. rapae and both taxa showed high return rates to gardens when released in the matrix.