Ropeless Pot
WHAT ARE ROPELESS POTS?
Ropeless (also known as remote-release or pop-up) pots and creels use triggers to release buoys, attached to submerged pots/creels, allowing them to float to the surface for retrieval. Such systems may be time controlled or use acoustic triggers, and negate the need for vertical lines in the water column, which pose a threat of entanglement for marine mammals and turtles.
Ropeless gears. (Top: Fiobuoy, DesertStar ARC-1, Ashored-Mobi. Bottom: LobsterLift, SMELTS LobsterRaft, EdgeTech 5112). Image credit: Kim Sawicki
CURRENT RESEARCH
Timed systems, which release pots at a pre-specified time, are potentially less effective than acoustic-release triggers, as they risk releasing when fishers are not yet in the vicinity. However, the technology is being refined to be more effective and cheaper. Successful testing has been completed in the USA for traps for lobster, crab, and bass to depths of about 90 metres in various ocean conditions and bottom types. A successful feasibility study was conducted in 1999 for the use of acoustic release systems in offshore lobster fisheries in the Gulf of Maine, USA, demonstrating that such systems could successfully be deployed. As yet, their implications for mitigating bycatch is undetermined, although trials are underway in Scotland and North America, and acoustic-release triggers are already in use in southern rock lobster fisheries in New South Wales, Australia. Researchers are also exploring the promising potential of technology that enables ropeless/buoyless pots to accurately report their locations to fishing and other vessels, although this is still in early stages.
Where switching to ropeless systems is not currently feasible, the Scottish Entanglement Alliance (SEA) recommends reducing excess rope in the water column by setting the riser length to the water depth and using a weighted rope on the riser. More recent research by the SEA has also revealed that a high proportion of whale entanglements are caused by groundlines, a rope which links creels (pots) together on the seabed and often floats. Research suggests that ensuring groundlines are made from a material that sinks and allows them to lie on the seabed could reduce entanglements
Interested in how this and other measures could mitigate bycatch in your fishery? Get in touch with us to collaborate or take part in a study.
This page was last updated on 14.06.23.