Local abundance and distribution of bottlenose dolphins (Tursiops truncatus) in the nearshore waters of Virginia Beach, Virginia

We investigated patterns of abundance and distribution for coastal migrator y Atlantic bottlenose dolphins (Tursiops truncatus) that appear seasonally in the nearshore waters of Virginia Beach, Virginia. The study was conducte d along 24 km of shoreline at the southern point of the Chesapeake Bay mout h from April 1994 to March 1995. This is the first study to investigate the relationship between the abundance of coastal migratory dolphins and facto rs that might affect their movement. A profile analysis of variance reveale d significant differences in local abundance and distribution throughout th e year. Dolphin number was positively correlated with water temperature and not correlated with photoperiod. Although prey distribution and abundance are two factors thought to affect dolphin presence, in this study the relat ionship between these two factors and dolphin abundance was unclear. Greate r numbers of dolphins were found in the ocean section of the study area. Ho wever, significantly higher ratios of neonatal dolphins were observed in th e bay section, suggesting the bay serves as a nursery area. The observed re lationship between local dolphin abundance and environmental factors in Vir ginia may provide insight into dolphin distribution and migration along the Atlantic coast of the United States.