Growth, reproduction, and feeding of large monkfish, Lophius americanus

The American monksh, Lophius americanus, supports important commercial sheries in the Northwest Atlantic. Although life historyinformation is available for smaller L. americanus, the biology of large monksh (.70 cm) is poorly understood because relatively fewlarge sh are caught in standard resource surveys.Between 2006 and 2008, 699 L. americanus of 71–118 cm total length were collectedfrom commercial gillnet shers operating in the mid-Atlantic Bight (n=689) and in the Gulf of Maine (n=10) to investigate growthrates, reproductive biology, and feeding habits of large monksh. All those collected were mature females ranging in age from 7 to 13years. Growth was linear at an average annual rate of 7.6 cm. Hepatosomatic indices peaked in February and gonadosomatic indicesbetween Februaryand April. Postovulatory follicles and vitellogenic oocytes were observed in the same ovaries, evidence that monkshspawn over a protracted period and possibly more than once annually. Food habits were similar to those reported for smaller benthicphase monksh, but cannibalism was more prevalent in large sh (5.6% frequency of occurrence). Frequencies of feeding and canni-balism were greatest in females in the nal stage of oocyte maturation.