Feeding chronology of six species of carcharhinid sharks in the western North Atlantic Ocean
Published online on 28. September 2012Feeding chronology of six species of carcharhinid sharks in the western North Atlantic Ocean as inferred from longline capture data
William B. Driggers III, Matthew D. Campbell, Eric R. Hoffmayer, G. Walter Ingram Jr.
ABSTRACT:
Time-at-capture data for 6 species of carcharhinid sharks were collected during 2692 fishery-independent longline sets conducted in the western North Atlantic Ocean from 1995 through 2009. As operations occurred continuously throughout the diel cycle, time-at-capture data were used as a proxy for natural feeding behavior to examine the diel feeding chronology of blacknose Carcharhinus acronotus, spinner C. brevipinna, bull C. leucas, blacktip C. limbatus, sandbar C. plumbeus, and Atlantic sharpnose Rhizoprionodon terraenovae sharks. All 6 species were collected during all hours of the diel cycle; however, application of circular statistics revealed that spinner, bull, blacktip and sandbar sharks increased their feeding activity during nocturnal hours. Atlantic sharpnose and blacknose sharks exhibited no significant directedness in time-of-capture, indicating that these 2 species lack distinct feeding patterns. The species-specific differences in feeding chronologies of the sharks examined demonstrate that broad generalizations concerning the feeding behavior of sharks are not appropriate.
Mar Ecol Prog Ser 465:185-192