The role of closed areas in rebuilding monkfish populations in the Gulf of Maine

  • Published source details Smith M.D., Grabowski J.H. & Yund P.O. (2008) The role of closed areas in rebuilding monkfish populations in the Gulf of Maine. ICES Journal of Marine Science, 65, 1326-1333.


This study is summarised as evidence for the following.

Action Category

Establish long-term fishery closures

Action Link
Marine Fish Conservation
  1. Establish long-term fishery closures

    A site comparison study in 2004–2005 of two areas of mud and gravel seabed in the Gulf of Maine, USA (3) found that year-round closure of an area to fisheries targeting bottom-dwelling fish (groundfish) for six to seven years, resulted in lower abundance and size of monkfish Lophius americanus abundance inside the closure area compared to outside, feeding intensity varied and condition was similar. Overall, monkfish abundance and size were lower inside the closure area than outside (data reported as statistical model results). The abundance of larger monkfish (401–800 mm) was similar inside compared to outside (inside: 0.3–0.8 fish/tow, outside: 0.3–1.2 fish/tow), but was lower for monkfish between 0–400 mm (inside: 0.3–0.8 fish/tow, outside: 1.3–2.7/tow). Stomach fullness of adult monkfish was higher inside (10 g/mm3), than outside (6 g/mm3), but juvenile (<300 mm) stomach fullness was similar (inside: 8 g/mm3, outside: 11 g/mm3). Monkfish condition was similar across protection levels (data reported as statistical model results). In addition, monkfish feeding intensity and condition were generally more strongly affected by habitat type than the closure. In autumn 2004 and spring 2005, a total of 32 otter trawl deployments were conducted at paired sampling sites, rock/cobble edge and mud, inside and outside, of the Western Gulf of Maine Closure Area. The area was closed to groundfish fishing in 1998, initially to reduce fishing mortality of key groundfish species such as cod. Monkfish were counted, lengths measured, weighed and stomach content recorded.

    (Summarised by: Leo Clarke)

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