ABSTRACT. Six adult belugas, Delphinapterus leucas, (2 males, 4 females) were instrumented with satellite-linked transmitters in Croker Bay, southeastern Devon Island in the Canadian High Arctic in mid-September 1995. Some days, the animals remained close to shore along the southeastern and eastern shoreline of Devon Island, presumably foraging for arctic cod (Boreogadus saida) and other prey. They spent the rest of the time in the deep waters of Lady Ann Strait, eastern Jones Sound, and the waters southeast of Coburg Island, presumably feeding on deepwater prey. Only males went farther north in waters off southeastern Ellesmere Island. The belugas' swimming speeds decreased in the later part of the study period. Their last transmissions came from the North Water, an area where belugas are known to winter. Results of this study were not sufficient to determine the extent of movement of belugas between the eastern Canadian Arctic and Greenland.

During the summer of 1998, the effects of boat activity on the behavior of bottlenose dolphins (Tursiops truncatus) were investigated using 52 shore-based surveys along Hilton Head Island, South Carolina. Temporal autocorrelation indicated data collected on most variables should be analyzed in 6-min intervals. Responses to boats were categorized as "no response," "behavioral response," "change in direction of movement," or "change in both behavior and direction." Multiple boats had a greater influence on dolphin behavior and movement than the presence of a single boat. Dolphin-watching boats, motorboats, shrimp boats, and jet skis affected the group size and behavior of dolphin groups. Dolphin groups responded to dolphin-watching boats during 20% of observations, mainly with a change in both behavior and direction of movement. Motorboats caused a response in dolphins during 55% of observations, with a change in behavior or both behavior and direction. Jet skis had a more dramatic effect on dolphin groups, with 56% of groups changing their behavior and 11% changing both their behavior and direction. Shrimp boats always elicited a response. Dolphin groups changed both their behavior, and direction of movement to follow and feed behind these boats. In contrast, ships rarely caused a response, with groups changing their behavior but not their direction in 11% of observations. As the number of boats in the Hilton Head area increased, dolphin groups heightened responses-that is, changed both behavior and direction of movement. These boat-related effects on bottlenose dolphin behavior are considered "harassment" under the U.S. Marine Mammal Protection Act (1972) and should be scrutinized by agencies responsible for public education and enforcement of protective legislation.

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