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A plane flying even 1 or 2 miles away may cause either single or flocked brant (Branta bernicla) to take to the air. In some areas, boating activity continually molests birds seeking food in their usual places. During the last 5 years high-speed boats are commonly used from British Columbia to San Quintin Bay in northern Baja California. The use of power dredges intimidates feeding birds in daylight and tends to destroy eelgrass beds. A boating disturbance was observed on Mission Bay, San Diego Harbor, on January 19, 1958. Here at low tide the brant geese could find sanctuary only in small elbows off the main channel in the bay, where they could drift up a mud-bottomed slough for perhaps a few hundred yards (a few hundred meters); but the continual traffic of high-speed boats, traveling at velocities of from 8-40 mph (12.9-64.4 km/hr), prohibited the birds from foraging on eelgrass beds or occupying open water in the channel. Boating activity on Humboldt Bay, California, is also forcing brant geese to spend their nights on the ocean. Serious losses result, for sleeping brant drift unconsciously into the breakers where the heavy sand content beats them down to the ocean floor and they wash ashore as "sanded" dead.