Philip D. Doherty

Fishing pots illuminated with light-emitting diodes (LEDs) could offer a lower-impact alternative to dredges for capturing European king scallops (Pecten maximus; hereafter ‘scallops’). However, low catch efficiency of pots could be a barrier to uptake and constrain the potential for any environmental gain. In this study, we sought to identify pot configurations that maximize scallop catch efficiency within illuminated pots, and to evaluate how these modifications influence catch efficiencies of two other target species: brown crab (Cancer pagurus), and European lobster (Homarus gammarus; hereafter ‘lobsters’). We investigated (i) LED colour, (ii) number of LEDs, (iii) pot base type, and (iv) pot entrance (hereafter ‘eye’) design across four spatially discrete experiments (69 fishing trips; 186 hauls; 3 559 pots). In total, 17 742 individuals from 48 species were caught, with 57% of catches comprising brown crabs (n = 6 612; 37%), scallops (n = 2 435; 14%), and lobsters (n = 1 025; 6%). Of the scallops captured, 99% (n = 2 407) were caught in illuminated pots. Catch efficiency of scallops was maximized using a standard metal-based pot fitted with a single white LED and elongated soft-eyes or ScallopEyes, particularly when deployed on scallop grounds. Neither blue LEDs, multiple white LEDs, nor rubber pot bases increased scallop catch efficiency relative to this configuration. In contrast, eye modifications designed to enhance scallop entry reduced brown crab catch efficiency, highlighting species-specific, spatially and seasonally targeted potting strategies could be more appropriate than a multi-species approach. If appropriately regulated alongside existing crustacean fisheries, scallop potting with LEDs could support sustainable diversification, not necessarily augmenting crustacean catches within pots, but increasing fishing options. These findings will contribute to broader conservation and climate objectives while enhancing the resilience of small-scale coastal fleets reliant on declining brown crab and lobster stocks.

Seabird bycatch in gillnet fisheries is a globally pervasive conservation issue, yet evidence for effective, scalable mitigation remains limited. In a gillnet fishery off the United Kingdom (1057 sets), we evaluated two above water deterrents (AWDs); “scarybird” kites (“kites” hereafter) and looming‐eyes buoys (LEBs) for reducing seabird bycatch. Both AWDs significantly reduced the chance of auk bycatch occurring (kites = −71%, LEB = −59% lower odds of a bycatch event) and magnitude when it did occur (kites = −62%, LEB = −68% reduction in bycatch per unit effort) relative to controls. Kites had a stronger deterrent effect < 30 m from the device whereas LEBs were moderately effective over a broader range. Bycatch peaked in winter, and where net mesh sizes were 100–120 mm, indicating that targeted deployments of AWDs can maximize conservation benefit, while minimizing operational disruption. Given the ubiquity of gillnet fisheries, simple, low‐cost AWDs offer a practical route to reducing bycatch and supporting conservation policy.

Reef manta rays ( Mobula alfredi ) are threatened by fishing and other anthropogenic threats. Which, when coupled with conservative life history traits, have made this species vulnerable to extinction. Spatiotemporal ecological knowledge, such as site fidelity and visitation patterns to key aggregation sites, are imperative for effective conservation management of M. alfredi . A novel method of environmental sensing, remote underwater photo systems (RUPs), was employed to understand drivers of M. alfredi habitat use and resighting patterns. RUPs were deployed at four cleaning sites around Laamu Atoll, Maldives. Between March 2021 and May 2023, 455,458 photos were analysed. Generalised linear models revealed increases in M. alfredi presence in response to high chlorophyll-a concentrations, low illumination moon states, the Southwest Monsoon, and in the morning, while human presence had no effect. Branchial spot patterns allowed for 81 M. alfredi individuals to be identified, from 629 sightings, representing 51.59% of Laamu Atoll’s previously identified population (n = 157). Cleaning stations are visited more intensively during periods of increased productivity of the Southwest Monsoon, likely in response to greater foraging opportunities near the study areas. Additionally, moon state, used as a proxy for tidal strength, was associated with increased visitation during new moon periods, suggesting that weaker tidal states may facilitate presence. These data support integrating RUPs with observational surveys to improve inferences about habitat use and our understanding of cleaning sites frequented by M. alfredi . This study aims to inform the implementation of Laamu Atoll’s first marine protected area management plan.

In Small Island Developing States (SIDS), coastal marine resources are particularly vulnerable to overexploitation, with small‐scale fisheries (SSF) providing an irreplaceable source of income and food. However, the decentralized and complex nature of SSF coupled with limited monitoring capacity hinders the design of effective measures to protect marine resources and local livelihoods. To address this knowledge gap, we implemented a participatory mobile device app‐based fisheries survey in 23 coastal communities of São Tomé and Príncipe (STP). Trained fishers and fish traders collected landing data from 12,403 unique fishing trips between 2019 and 2023 and recorded vessel activity on 620 sampling days. Catch and effort varied seasonally, with species composition varying across métiers (fishing types). While fishers demonstrated the ability to switch across métiers to target different species, catches were dominated by a few abundant species, notably blue runner and flying fish. Catch biomass and species richness, as well as biomass of demersal large‐bodied species, were lower on São Tomé Island compared to Príncipe Island, likely reflecting historical impacts of higher fishing effort. By combining community participation with digital tools, this approach generated high‐resolution data previously inaccessible to national authorities and provided actionable insights for fisheries governance in STP. Our findings highlight the value of participatory, mobile device‐based monitoring for filling knowledge gaps in SIDS, demonstrating how such approaches can guide conservation priorities while integrating resource users in fisheries management.

[This corrects the article DOI: 10.1371/journal.pone.0312849.].

The recent Kunming-Montreal Global Biodiversity Framework (GBF) sets ambitious goals but no clear pathway for how zero loss of important biodiversity areas and halting human-induced extinction of threatened species will be achieved. We assembled a multi-taxa tracking dataset (11 million geopositions from 15,845 tracked individuals across 121 species) to provide a global assessment of space use of highly mobile marine megafauna, showing that 63% of the area that they cover is used 80% of the time as important migratory corridors or residence areas. The GBF 30% threshold (Target 3) will be insufficient for marine megafauna’s effective conservation, leaving important areas exposed to major anthropogenic threats. Coupling area protection with mitigation strategies (e.g., fishing regulation, wildlife-traffic separation) will be essential to reach international goals and conserve biodiversity.

Understanding species distribution across habitats and environmental variables is important to inform area-based management. However, observational data are often lacking, particularly from developing countries, hindering effective conservation design. One such data-poor area is the Gulf of Guinea, an understudied and biodiverse region where coastal waters play a critical role in coastal livelihoods. Here, we describe the results of the largest national-scale Baited Remote Underwater Video Systems (BRUVS) survey in the region, aiming to understand the effects of several environmental variables on fish community composition and diversity. From 2018 to 2020, we successfully deployed 417 benthic BRUVS in the coastal waters of the São Tomé and Príncipe (STP) archipelago. Species richness and relative abundance were higher in deeper waters, on steeper slopes, and in rocky reef habitats. Nevertheless, maerl and sand habitats also hosted unique, and economically important species. Our results potentially indicate historical impacts of fishing in the archipelago, especially in São Tomé Island, where observed fishing effort is higher. Indeed, abundance of large predatory fish was low in both islands and abundance of species targeted by artisanal fisheries was lower in São Tomé than in Príncipe. Our results provide crucial information supporting the designation and future monitoring of marine protected areas in STP.

Global catch rates of sharks and rays from artisanal fisheries are underreported, leading to a lack of data on population status. This forms a major barrier to developing effective management plans, such is the case in Central and West Africa. Over 3 years, we undertook the first systematic quantitative assessment of sharks and rays landed by an artisanal fishery in the Republic of the Congo. During 507 sampling days (mean 14 surveys per month), we recorded 73,268 individuals. These comprised 42 species, of which 81% are considered at an elevated risk of extinction. Landings were dominated by immature individuals, especially for species of conservation concern. Presence of species thought to have largely disappeared from the region such as the African wedgefish ( Rhynchobatus luebberti ) and smoothback angelshark ( Squatina oculata ) suggest Congolese waters are a potential stronghold for these species—warranting increased protection. We identified seasonality of catch within years, but not across years. Both inter‐ and intra‐annual trends varied by species, signifying annual fluctuations in catch of each species but consistent catch of all species year‐on‐year. Analysis showed increased catch between the short‐wet and the long‐wet, and the long‐dry seasons (January–February and August–September). Lowest catch was shown to occur during the short‐wet and the short‐dry seasons (October–December), which may provide an opportunity for seasonal closures or gear restrictions.