Stock discrimination of American Monkfish Northwest Atlantic Using Mitochondrial DNA

The monkfish (Lophius americanus) supports one of the most lucrative fisheries in the northwest Atlantic Ocean. Despite a paucity of life history, genetic or behavioral data, monkfish management in the US divides the species range into Northern and Southern Management Areas (NMA and SMA). However, little is known of stock structure, an understanding of which is critically important to population assessment. At present, the monkfish resource in each area is assessed as if it were a unit stock, with no exchange between areas. Monkfish were collected from winter 2008-spring 2009 from Cape Cod to Cape Hatteras during the NOAA Living Marine Resources Cooperative Science Center research cruise and the NEFSC Cooperative Monkfish Survey cruises. Fin clips and liver samples were taken and preserved in 99% ethanol from individual fish for mitochondrial DNA (MtDNA) extraction. The cytochrome oxidase I (COX-I) gene was used as a marker for population genetic analysis to determine if there are identifiable genetic stocks and how they relate to the management areas. Our results showed genetic differentiation among three groups, in correlation to the management areas. There is no geographic isolation observed among the three groups.