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Incidental catch of the loggerhead sea turtle (Caretta caretta) in the Mediterranean basin is the main threat to its conservation. In this basin, fisheries are multi-species, multi-gears and multi-national, making demersal fishing activities profitable, while preserving sea turtles is a challenge. In this study, scientists developed bycatch reducer devices and alternative fishing gears to mitigate the impact of demersal fishing gears on sea turtles. This included (i) testing hard and flexible Turtle Excluder Devices in bottom trawling nets and (ii) using ultraviolet LEDs as visual deterrents to illuminate set nets to avoid entanglement. The results of this study suggest the different devices did not affect the commercial catch, while bycatch reduction was instead evident. These results advocate for a global effort to introduce bycatch reduction devices in different areas and fisheries of the Mediterranean. 

Experiments using squid dyed with Brilliant Blue dye were undertaken aboard tuna longline vessels off East Cape, New Zealand, to determine the dyed baits ability to reduce the incidental capture of seabirds.  Significant differences in catch rates between bait types were observed when all species were combined and for seabird mortality, but the authors identified problems with the statistical design, which make the results not very convincing and therefore inconclusive.  In addition, at sea observations of seabird behavior during the deployment of the longline gear, suggest the dye did not effectively camouflage the bait.  Instead the authors suggest seabirds may reject the blue dyed bait due to its color after either seeing it or investigating it through pecking and/or eating.

This study compared the selectivity of two sorting grids (G1-SM40 and G20-ST20) and a T90 codend to a control trawl in a commercial bottom trawl fishery  targeting deep-water rose shrimp (Parapenaeus longirostris) and European hake (Merluccius merluccius) in the central Mediterranean. All modified gears reduced catches of undersized shrimp and hake. The sorting grids improved target-species selectivity and reduced benthic discards relative to the control, and the T90 codend substantially reduced elasmobranch bycatch, particularly juveniles. Economic assessments showed that, although catch rates and revenues declined slightly, discard ratios decreased and selectivity improved, indicating a more sustainable exploitation pattern. Fuel consumption remained unchanged among gears, demonstrating that these modifications do not affect vessel energy performance.

This review highlights the diversity of fishing gear used in inland fisheries, particularly in small-scale and artisanal fisheries, as well as gear regulations and management. Set gillnets are the most common type of fishing gear in use. Inland fishing gear is associated with environmental impacts that pose conservation challenges, including bycatch. The principal gear regulations in place for inland fisheries are mesh size limitations, bans on specific gear and closed seasons. 

This study examined global research trends and innovation pathways in trap fisheries using bibliometric indicators from Scopus-indexed publications between 2000 and 2025. 605 strongly relevant journal articles were retained for bibliometric analysis. Trap fisheries research has expanded steadily over the time period, with an annual growth rate of 4.93%, involving 2,090 authors across 205 publication sources. Thematic analysis indicated that trap fisheries research was mainly concentrated on species composition and biodiversity, trap design and fishing technology, habitat and ecosystem impacts, monitoring and data analytics, and fisheries management. In contrast, more specific themes such as bycatch mitigation, gear selectivity, ghost fishing, and fyke-net or set-net fisheries were less represented, although they are increasingly relevant in recent studies.

A modified single-layer codend configuration developed from previous studies was evaluated using BRDs with guide net angles of 30° and 45°. For target species, catch loss rates based on the number and weight of individuals were 9% and 13%, respectively for herring (Culpea pallasii) with the 30° guide net and 16% and 18% with the 45° guide net. For Korean pomfret (Pampus echinogaster), catch loss rates were 24% and 23% at 30° and 4% at 45°. Catch loss rates of target mackerel (Scomber jamponicus) with the 30° guide net reached 56%, whereas hairtail (Trichiurus lepturus) had loss rates of 60% and 65% with the 45° guide net. These results suggest that further modification of BRD is necessary. However, no bycatch of marine mammals occurred during the experimental operations, despite dolphins being observed nearby.

Two types of excluder devices, one with exclusion bars and one with exclusion rings, were fitted at the entrance to fyke nets to determine their efficiency in reducing turtle bycatch.  In addition, the efficacy of an escape chimney, compared to a net with a large hole, was tested.  The exclusion device with bars across the net significantly reduced turtle catch rates.  Fish catch rates were not impacted by either excluder device.  All turtles were able to escape through the escape chimney, while the majority of fish (88%) were retained.  In comparison, 60% of turtles and 77% of fish were able to escape through the a large hole in the net.  The escape chimney was therefore the most effective at avoiding turtle bycatch while retaining fish.

Harbour porpoise (Phocoena phocoena) bycatch was significantly lower (p<0.01) in high-density Iron Oxide (IO) gill nets compared to control nets. There was no significant difference in the acoustic target strength of the IO and control nets, and both nets behaved similarly in flume tank tests. The authors conclude the reduction of harbour porpoise bycatch in the IO nets was a result of the mechanical properties of the nets.

This investigation details an unusual encounter with a lunge-feeding minke whale (Balaenoptera acutorostrata) with fresh entanglement-like injuries to its head and ventral pouch.  It also discusses results from a short-term comparative study that tested whether the whale fed differently than five uninjured minke whales feeding in the same area.  Collectively, this study: 1) quantifies how much a rope-like injury can restrict the expansion of a minke's ventral pouch while feeding, 2) provides the first minke whale lunge-feeding velocities from a photogrammetric method using digital video, and 3) describes a new lunge-feeding aerial maneuver for minke whales that is possibly associated with the injury.

Field experiments were conducted to determine behavioral responses of minke whales (Balaenoptera acutorostrata) to experimental ropes and buoys made up of different colors, simulating those used in crab and whelk fishing gear. Trials were conducted with yellow, orange, green, blue, white and black ropes. Visual and acoustic monitoring was used to assess behavioral responses of whales to the different experimental gears. In addition, remote sensing equipment was used to monitor oceanographic conditions, underwater sounds and to video the whales as they swam near the experimental ropes. The results indicated a positive correlation between whale approach velocity and departure velocity and bearing changes. Minke whales decreased their swimming velocity and altered their bearing when passing by these ropes and increased their velocity once they had passed by the ropes. This was most evident when the ropes were black and white. Low frequency vocalizations and altered swimming trajectories were also noted in some whales as they passed near the ropes.