Most hydraulic dredges have a cutting head to assist with dislodging compacted sediment, breaking it up, and feeding it into the suction of the pump. The excavator dredge attachment is a hydraulic dredge that includes a high-powered EDDY Pump and cutterhead. This can be done with use of a hydraulic excavator dredge pump attachment. Sometimes, however, the material will be easier removed by barge, which can easily be accomplished when using barge-deployed EDDY Pump dredging equipment. Dredged material is often disposed into self-contained hoppers of the dredgers, in barges, pumping through pipelines, and using natural forces such as waves and currents. Typically, when dredging, the discharged material, or material to be removed, will be pumped to a specified location like a holding pond or tank where it is then properly disposed of. Many times, it depends on the type of dredging that will be performed, which will generally determine what type of dredging equipment and deployment options that will be available. Read the opinion document (PDF, 297 pages).Dredging can be conducted from the land by using an excavator or submersible dredge pump, or from the water by utilizing a barge or amphibious type of deployment. In April 2021, NOAA Fisheries completed its most recent evaluation of the impacts to sea turtles and other protected species from southeast shrimp fisheries under Section 7 of the Endangered Species Act. waters of the Gulf of Mexico and South Atlantic are required by federal law to equip their trawls with a TED.
Today, many shrimp trawlers operating in the U.S. NOAA Fisheries gear experts continue to work with the shrimp fishing industry to develop new and effective ways to reduce bycatch. Current TED designs have been determined to be 97 percent effective in excluding turtles from shrimp trawls. When larger animals like sea turtles enter the trawl net, they are redirected by the TED and are able to exit through an opening either at the top or bottom of the net. Small animals, such as shrimp, pass through the grid into the mesh bag at the end of the trawl and are caught. The modern TED is a simple grid made of metal bars that is fit into a trawl net. The result of over a decade of gear development, and subsequent evaluation, was the turtle excluder device. Our Harvesting Systems Unit, with assistance from the commercial shrimping industry, initiated research to develop solutions to this problem. By the late 1970s, incidental bycatch of sea turtles in shrimp trawling gear in the southeastern United States was determined to be a major threat to the survival of sea turtle populations. waters are listed under the Endangered Species Act as either threatened or endangered.
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