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

The American monkfish, Lophius americanus, supports important commercial fisheries in the Northwest Atlantic. Although life history information is available for smaller L. americanus, the biology of large monkfish (.70 cm) is poorly understood because relatively few large fish are caught in standard...

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Bibliographic Details
Main Authors: A. K. Johnson, R. Anne Richards, Daniel W. Cullen, Ra J. Sutherl
Other Authors: The Pennsylvania State University CiteSeerX Archives
Format: Text
Language:English
Published: 2008
Subjects:
Online Access:http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.501.6190
http://www.nefsc.noaa.gov/read/popdy/monkfish/Publications/ICES J 2008 Johnson et al.pdf
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Summary:The American monkfish, Lophius americanus, supports important commercial fisheries in the Northwest Atlantic. Although life history information is available for smaller L. americanus, the biology of large monkfish (.70 cm) is poorly understood because relatively few large fish are caught in standard resource surveys. Between 2006 and 2008, 699 L. americanus of 71–118 cm total length were collected from commercial gillnet fishers operating in the mid-Atlantic Bight (n = 689) and in the Gulf of Maine (n = 10) to investigate growth rates, reproductive biology, and feeding habits of large monkfish. All those collected were mature females ranging in age from 7 to 13 years. Growth was linear at an average annual rate of 7.6 cm. Hepatosomatic indices peaked in February and gonadosomatic indices between February and April. Postovulatory follicles and vitellogenic oocytes were observed in the same ovaries, evidence that monkfish spawn over a protracted period and possibly more than once annually. Food habits were similar to those reported for smaller benthic phase monkfish, but cannibalism was more prevalent in large fish (5.6 % frequency of occurrence). Frequencies of feeding and canni-balism were greatest in females in the final stage of oocyte maturation.