Preliminary data on cold-water corals and large sponges by-catch from Spanish/EU bottom trawl groundfish surveys in NAFO Regulatory Area (Divs. 3LMNO) and Canadian EEZ (Div. 3L): 2005-2007 period

Since 2005, by-catch of vulnerable invertebrates, such as cold-water corals and large sponges, has been studied with special attention in the Spanish/EU bottom trawl groundfish surveys in Northwest Atlantic (NAFO Divs. 3LMNO). Based on this research, twenty-nine different taxa of cold-water corals h...

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Bibliographic Details
Main Authors: Murillo, Francisco Javier, Durán-Muñoz, Pablo, González-Troncoso, Diana, Serrano, Alberto
Format: Report
Language:English
Published: 2008
Subjects:
Online Access:http://hdl.handle.net/10508/731
http://hdl.handle.net/10261/328974
Description
Summary:Since 2005, by-catch of vulnerable invertebrates, such as cold-water corals and large sponges, has been studied with special attention in the Spanish/EU bottom trawl groundfish surveys in Northwest Atlantic (NAFO Divs. 3LMNO). Based on this research, twenty-nine different taxa of cold-water corals have been preliminarily identified in the study area: five alcyonaceans, ten gorgonaceans, ten pennatulaceans, three solitary scleractinians and one antipatharian. No colonial scleractinians were recorded during these surveys and reef structures are unlikely to occur in the study area. The main large sponges found belong to the family Geodiidae. The volume of cold-water corals and large sponges in the by-catches was generally low in the regularly-used fishing grounds studied. Most of the by-catches were recorded in hauls carried out in areas outside of regular fishing grounds for the bottom trawlers. By-catches of large gorgonians were recorded in three small areas located in Divs. 3LM (two in Div. 3L and one in Div. 3M), indicating that Vulnerable Marine Ecosystems (VMEs) could occur there. Pennatulaceans, solitary scleractinians, alcyonaceans and antipatharians were also observed as part of bycatch in some hauls carried out in Divs. 3LMO, but it is not clear if these by-catches indicate presence of VMEs in the area sampled. Highest diversity of coral species was found in Div. 3M. Large sponges occurred in deep waters, in a narrow band along Northern slope of the Grand Banks (Div. 3N) and Southern Flemish Pass (Div. 3L) as well as in several patches located in North-eastern and Eastern Flemish Cap. The preliminary information presented here, derived solely from bottom trawl survey by-catch records, it is not enough for identification of VMEs accurately, but it is very valuable to give a general view of where VMEs like to occur or not occur. Previous experience from other North Atlantic high-seas fishing grounds (e.g. NEAFC Regulatory Area) suggests that additional geohabitat mapping and information on fishery ...