Lobster fishing is an iconic element of communities in Downeast Maine. Lobster traps are typically baited with herring, Clupea harengus, which is discarded when traps are pulled. Some lobstermen toss bait immediately overboard, while others bucket the bait for later disposal. Prior studies show that a significant portion of food fed to young gulls in Maine consists of lobster bait discards. During the summer of 2008, I observed gulls responding to lobster boats fishing in the vicinity of Great Duck Island, an off-shore island in the western Gulf of Maine. Over the course of 6 weeks I was able to observe gull behavior around 30 boats, with repeat observations of vessels concentrating their activity in the immediate vicinity of the island. I also analyzed 20 samples of food boli regurgitated by young gulls during banding procedures. Flock sizes around boats were recorded for fishing vessel behaviors that included rapid transit, slow, stop, turn, hauling trap, trap up, toss lobster and bait over. Gull numbers in the vicinity of lobster boats increased in apparent response to visual cues from gulls already over boats and also to lobster boat activity. Peak numbers of gulls (Max = 57) were observed over boats that were actively tossing bait. Some gulls persisted in following boats that were not throwing bait, although flock size never exceeded 12. Eight out of 20 sample food boli contained lobster bait. Bait was found in samples collected on both clear and extremely foggy days, suggesting that gulls may also use aural cues to locate fishing vessels.

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