Groupers are a valuable fishery resource of reef ecosystems and are among those species most vulnerable to fishing pressure because of life history characteristics including longevity, late sexual maturation and aggregation spawning. Despite their economic importance, few grouper fisheries are regularly monitored or managed at the species level, and many are reported to be undergoing declines. To identify major threats to groupers, the International Union for Conservation of Nature (IUCN) Red List criteria were applied to all 163 species. Red List assessments show that 20 species (12%) risk extinction if current trends continue, and an additional 22 species (13%) are considered to be Near Threatened. The Caribbean Sea, coastal Brazil and Southeast Asia contain a disproportionate number of Threatened species, while numerous poorly documented and Near Threatened species occur in many regions. In all, 30% of all species are considered to be Data Deficient. Given that the major threat is overfishing, accompanied by a general absence and/or poor application of fishery management, the prognosis for restoration and successful conservation of Threatened species is poor. We believe that few refuges remain for recovery and that key biological processes (e.g. spawning aggregations) continue to be compromised by uncontrolled fishing. Mariculture, through hatchery‐rearing, increases production of a few species and contributes to satisfying high market demand, but many such operations depend heavily on wild‐caught juveniles with resultant growth and recruitment overfishing. Better management of fishing and other conservation efforts are urgently needed, and we provide examples of possible actions and constraints.

Effective ocean management and conservation of highly migratory species depends onresolving overlap between animal movements and distributions, and fishing effort.However, this information is lacking at a global scale. Here we show, using a big-data approach that combines satellite-tracked movements of pelagic sharks and global fishing fleets, that 24% of the mean monthly space used by sharks falls under the footprint of pelagic longline fisheries. Space-use hotspots of commercially valuable sharks and of internationally protected species had the highest overlap with longlines (up to 76% and 64%, respectively), and were also associated with significant increases in fishing effort.We conclude that pelagic sharks have limited spatial refuge from current levels of fishing effort in marine areas beyond national jurisdictions (the high seas). Our results demonstrate an urgent need for conservation and management measures at high-seas hotspots of shark space use, and highlight the potential of simultaneous satellite surveillance of megafauna and fishers as a tool for near-real-time, dynamic management.Industrialised fishing is a major source of mortality for large marine animals (marine megafauna) 1-6 . Humans have hunted megafauna in the open ocean for at least 42,000 years 7 , but international fishing fleets targeting large, epipelagic fishes did not spread into the high seas (areas beyond national jurisdiction) until the 1950s 8 . Prior to this, the high seas constituted a spatial refuge largely free from exploitation as fishing pressure was concentrated on continental shelves 3,8 . Pelagic sharks are among the widest ranging vertebrates, with some species exhibiting annual ocean-basin-scale migrations 9 , long term trans-ocean movements 10 , and/or fine-scale site fidelity to preferred shelf and open ocean areas 5,9,11 . These behaviours could cause extensive spatial overlap with different fisheries from coastal areas to the deep ocean. On average, large pelagic sharks account for 52% of all identified shark catch worldwide in target fisheries or as bycatch 12 . Regional declines in abundance of pelagic sharks have been reported 13,14 , but it is unclear whether exposure to high fishing effort extends across ocean-wide population ranges and overlaps areas in the high seas where sharks are most abundant 5,13 .Conservation of pelagic sharkswhich currently have limited high seas management 12,15,16would benefit greatly from a clearer understanding of the spatial relationships between sharks' habitats and active fishing zones. However, obtaining unbiased estimates of shark and fisher distributions is complicated by the fact that most data on pelagic sharks come from catch records and other fishery-dependent sources 4,15,16 .Here, we provide the first global estimate of the extent of space use overlap of sharks with industrial fisheries. This is based on the analysis of the movements of pelagic sharks tagged with satellite transmitters in the Atlantic, Indian and Pacific oceans, together with fishing vessel movements m...

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1 investigated seasonal, lunar and diel patterns in the spawnlng behaviour of a serranid, the common coral trout Plectropomus leopardus, on the Great Barrier Reef, Australia, uslng underwater visual census surveys. The study was conducted a t Scott and Elford Reefs, 2 mid-shelf reefs off Calrns, for 4 and 3 yi-, respectively. At each reef, coral trout aggrcgdted and spawned at the same 'primary' aggregation slte in each year. Primary sltes are defined as those with the largest aggregations of coral trout. Spawning activity, though not lim~ted to, was concentrated a t primary sites. The aggregatlon site at Scott Rccf measured l? 00 m' in area, and that a t Elford Rc.ef 3200 m' Maximum numbers of coral trout recorded in these sites were 128 fish a t Scott Reef and 59 a t Elford Reef. Coral trout aggregated and spawned at the primary sites around 3 consecutive new moons each year within the period August-Decembcr. 1991 to 1993 In 1990 only 2 aggregatlons were detected at Scott Keet, both around the new moon The largest aggregations were recorded at the primary s~t e at Scott Reef: numbers of fish at the aggregation site rose from an average prc-spawning density of 3.9 fish 1000m-' to aggregation densities ranglng from 37.1 to 75.3 fish lOOOm -'. The median size class of aggregating fish was 41 to 45 cm FL (forklength) at both reefs in all years. with a maximum range of 16 to 80 cm FL a t Scott Reef, and 16 to 65 cm FL dt Elford Reef The onset of the spawnlng season col-I-esponded with a rlse in water temperature (>24.00dC) after the austral winter. Spawning aggregations occurred for an average of 5 d , however aggregatlons were not found at the sltes throughout the day. The aggregatlons appeared to disperse in the morning and re-establish after 13:00 h. (:oral trout spawned in pairs predominantly on flooding tides and when current flow at the spawning sites was minimal. Ninoty-four spawning rushes were observed which only occurred during a 33 (i4 SE) min period spanning sunset. The spatial and temporal predictability of P. leopardus spawning aggregatlons makes them vulnerable to overfishlng, but also amenable to specialised management through s e~~s o n a l and/or spatlal closures

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