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Are you a longliner plagued with a shark bycatch problem? Well, not to worry. The Super Polyshark just might be the thing to keep sharks away from your hooks. This is a semiochemical shark repellent that when added to bait forms an odor plume in the water that repels sharks.

Super PolysharkIt was tested in Florida’s swordfish fishery and reduced shark bycatch by as much as 70 percent, while maintaining the target catch rate. Super Polyshark also holds the promise of reducing shark bycatch in tuna and swordfish longline fisheries around the world. 

That’s why Super Polyshark’s designers, Florida researchers Eric Stroud and Patrick Rice won a $10,000 runner-up prize in the 2014 World Wildlife Fund’s International Smart Gear Competition. WWF started the competition in 2004 to develop innovative but practical fishing gear to reduce the decline of fish and other marine species caused by bycatch.

The prize for the second runner-up went to a German group made up of scientists and fishermen who came up with the Freswind (Flatfish Rigid Escape Windows) to release flatfish from a trawl.

2015 115 Freswind Smart Gear figure 2Freswind Generally, a grid system in a trawl is better at releasing round fish than flatfish. Using behavioral differences between fish species, the developers of Freswind determined the most appropriate angle and spacing of vertical bars within a grid to reduce flatfish bycatch. The results have shown a bycatch reduction of 54 to 66 percent.

Of the 26 albatross species that have been identified, 25 are listed as endangered, and longline fishing is a big reason for those declines. Thus when a Dutch team came up with an innovative idea to reduce bycatch in longline fisheries that is also in improvement over the use of streamer lines, they were awarded a $7,500 Special Bycatch Reduction in Tuna Fisheries Prize.

2015 115 Seabird Saver Smart Gear installation1Seabird SaverThe Seabird Saver uses a laser and optional acoustic stimulus to keep birds away from fishing areas, thus reducing bird bycatch while not affecting the catch rate.

The laser’s beam and the “scattering” effect when it hits the waves is said to be a powerful bird deterrent. It’s seen as a threat and the birds move away. The laser is designed so that it won’t cause retinal damage to the birds.

As opposed to streamer lines, the Seabird Saver should be able to be used in strong wind conditions, which restricts the use of streamer lines.

OK. Now the $30,000 Grand Prize. It went to a group of Norwegians for a device to reduce bycatch in purse seine fisheries. A problem with mackerel, herring, capelin, anchovy and sardine fisheries is when the net is pursed up close to the boat, and it is discovered the fish are the wrong size or quality, they have to be “slipped” or released. Because of high stress levels and fish being jammed up against each other, this results in a lot of dead fish.

2015 Air Powered Sampler Grand Prize Smart Gear DSC 0002Air Powered SamplerThe Air Powered Sampling System allows fishermen to obtain a sample of the fish before they are brought next to the boat. The Air Powered Sampling System consists of a mini trawl packed into a plastic tube that’s loaded into a pneumatic line thrower. 

The plastic tube is shot into the purse seine up to 50 meters away. When a length of thin line is stretched out, it pulls the trawl out of the tube just before it hits the water. The tube and trawl sink into the purse seine, gathering a sampling of fish, and are then pulled back to the boat with a small hydraulic winch. If the fish are not the right size or quality, the purse seine can be opened up and the fish released without a high mortality rate.

Markets for the Air Powered Sampling System are considered to be the North Sea herring fishery, sardine fisheries of West Africa, and the anchovy fisheries of Peru.

A question has to be what will happen to these ideas? Do they ever get on a boat? Once the prizes are awarded, the WWF says it works with each winner to see their idea implemented in fisheries. Forty percent “of the winning ideas identified by the competition in previous years are being used regularly in different types of fisheries,” says Bill Fox, WWF’s fisheries vice president in a press release.

 

 

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