Movement of bottlenose dolphins around the south‐west coast of Britain

After an absence of two decades a group of bottlenose dolphins, Tursiops truncatus, became resident in the coastal waters of Cornwall, U.K. in 1991. Using a combination of field techniques and information from the general public, the movements of this group were monitored. The dolphins demonstrated a seasonal residency pattern, spending the winter in southern Cornwall and moving further north‐eastward during spring and summer. Residency was flexible with a number of individual dolphins using the region intermittently. The dolphins occupied a linear range of coast of 650 km. Within this range they repeatedly made long‐distance journeys. Mean swimming speed was documented at 7.9 km·h−1, with the dolphins travelling the coast at a mean of 3.6 km·h−1. The longest journey recorded covered 1076 km and took 20 days. In one confirmed case the dolphins left the south‐west of England and were resighted in Wales. Such wide ranging movements have important implications for the conservation of bottlenose dolphins in U.K. waters.