Sunday, April 17, 2011

Draggers are they sustainable?

Continuing from last week's series on the types of gear that local fishermen use to catch fish for CAFC, this week I will discuss draggers. Draggers are the predominate type of gear used to catch groundfish in New England. Draggers tow nets along the ocean floor (and sometimes in the mid-water column for fish such as herring). The nets are held open by metal 'doors' that help spread the mouth of the net open. A chain runs along the bottom often lined with 'scrubers' or 'rollers' which help the net to bounce over rocks and other impediments. The fish cannot outswim the net and are forced into it, ending up in the 'codend'.


By the criteria we discussed last week: selectivity and ocean impact, draggers score low on both counts. They are indiscriminate fishers, however many modern draggers use large mesh, and sophisticaed electronics to reduce by-catch. And, they have arguably the greatest impact on the ocean bottom.

Some dragger fishermen argue that in some cases dragging is much like tilling the soil and may actually result in increased fecundity. There is some evidence for this in species like scallops and flounders.

Many CAFC folks ask whether dragging (sometimes also called trawling, which is not the same as trolling) is sustainable, andthe answer like most things in the fish business is a little yes and a little no. Small scale draggers are incredibly efficient fishers. When the fish are in close to Gloucester, a dragger can go out and back in less than twenty-four hours with a full hold of fish.

Further, Captains like Joe Orlando argue that he has been fishing the same grounds for thirty years and that if draggers were wiping out the habitat, they would not be abl to continue to fish over and over in the same spots. As with most things in life, it is really a question of moderation vs. excess. Small scale day-boat draggers while not the ideal gear type are relatively benign. The problem is when you have large vessels with nets the size of football fields systematically towing patterns over the bottom that large scale habitat destruction occurs.

Another huge problem is when draggers target spawning aggregations. As we've come to learn many of our local groundfish are a lot more like salmon than we ever thought in that they return to the same breeding grounds over and over. When a dragger (or a gillnetter) wipes out a spawning mass, that sub-population could be wiped out for decades or even as they are seeing in Atlantic Canada and Downeast Maine, populations just cannot rebuild despite the absence of fishing.

I am loathe to incite gear conflict issues. There really is a place out there in the ocean for all the types of fishing. Some areas/fisheries are better suited for dragging, others work well as hook and line fisheries. The answer is a diverse fleet and a better understanding of ocean eco-systems to help protect sensitive areas and spawning biomass's.

No comments:

Post a Comment