Monkfish fishing takes place in one of the most challenging environments for any bottom fishing gear, since this species is typically found sheltering among rocky blocks, crevices, and uneven seabeds, forcing vessels to set their lines in areas where the risk of snagging is especially high. For those working with bottom longline fishing, these losses are part of daily operations, though an increasing number of design solutions are helping to minimize them.
Across many European fleets, bottom longline fishing remains one of the most widely used techniques for catching monkfish selectively. The system allows fishing in areas where other gear types face greater limitations, though with a well-known drawback: the more rugged the seabed relief, the higher the likelihood that the gear will get caught during setting or hauling.
Monkfish habitat explains the challenges of catching it
Monkfish mainly live at depths between 50 and 1,000 meters, depending on the species and geographic area. They seek out hard, mixed, or rocky seabeds where they can hide easily thanks to their extraordinary camouflage ability. From this motionless position, they wait for prey to come close before capturing it with a rapid snap of their enormous mouth.
This preference for uneven seabeds shapes the entire fishing strategy of fishermen and shipowners. Vessels must work over a seabed relief riddled with blocks, crevices, and drops that increase the risk of the gear getting caught. The more complex the seabed, the greater the chances of losing part of the equipment during the maneuver.
How weight design improves fishing gear for rocky seabeds
Although the weight has traditionally been considered a secondary part of the gear, its design directly affects how it interacts with the seabed.
Low-profile weights with rounded surfaces and cylindrical or spherical shapes present fewer points likely to get caught between rock blocks. Rather than wedging into a crevice, they tend to slide or roll over obstacles, reducing the likelihood of snagging during both setting and hauling.
In this area, GreenCastSea offers a line of eco sinkers made from recycled, lead-free zinc alloy, designed for professional applications. Its catalog includes the Sare range, with cylindrical and spherical models designed for different working conditions; the Hari series, developed for various net configurations through variants with different eye diameters; and Soka, a line of eco-friendly weights combining strong corrosion resistance, durability, and lower environmental impact compared to conventional sinkers. Beyond these standard solutions, the company also manufactures custom weights, adapting shape, size, and weight to the technical requirements of each fleet or fishery.
This approach makes it possible to select configurations better suited to each type of fishing, optimizing gear performance while keeping in mind the resistance, durability, and sustainability criteria that are becoming increasingly important in professional fishing.
That said, categorical claims should be avoided. Even patents developed specifically to make snag-resistant weights acknowledge that no geometry can completely prevent a sinker from ending up lodged in a seabed cavity. Shape helps minimize the risk, but its effectiveness also depends on the material used, the gear configuration, and fishing conditions.
More sustainable materials for more efficient professional fishing
Reducing losses isn't just an economic matter. Every weight left on the seabed adds to the problem of abandoned fishing gear, and when made of lead, it also introduces a heavy metal whose toxicity and bioaccumulation potential are well documented.
For this reason, the sector is moving toward alternative materials such as recycled zinc, which performs well in professional applications, is recyclable, and reduces environmental impact in case of accidental loss. This shift responds both to sustainability criteria and to the need to stay ahead of increasingly strict regulations on lead use in certain applications.
Innovation to reduce losses without compromising performance
The evolution of fishing gear for rocky seabeds depends on optimizing every component. In a fishery as demanding as monkfish fishing, small changes in weight design can help reduce snags, cut material losses, and improve the efficiency of fishing operations.
In this context, specialized manufacturers like GreenCastSea develop standard and custom fishing weights tailored to the needs of each fishery. The goal isn't to eliminate a problem inherent to rocky seabeds, but to offer solutions that allow for safer operations, lower operating costs, and progress toward more sustainable fishing.