The blue shark (Prionace glauca) is the most frequently captured shark in pelagic oceanic fisheries, especially pelagic longlines targeting swordfish and/or tunas. As part of cooperative scientific efforts for fisheries and biological data collection, information from fishery observers, scientific projects and surveys, and from recreational fisheries from several nations in the Atlantic and Indian Oceans was compiled. Data sets included information on location, size and sex, in a total of 478,220 blue shark records collected between 1966 and 2014. Sizes ranged from 36 to 394 cm fork length.Considerable variability was observed in the size distribution by region and season in both oceans. Larger blue sharks tend to occur in equatorial and tropical regions, and

The occurrence of tiger shark Galeocerdo cuvier in the Atlantic Ocean was assessed using at-sea observer data from multiple pelagic longline fisheries. Geographic positions of 2764 G. cuvier recorded between 1992 and 2013 and covering a wide area of the Atlantic Ocean were compared with the currently accepted distribution ranges of the species. Most records fell outside those ranges in both the Southern and Northern Hemispheres, which strongly suggests that the distribution range of G. cuvier in the open ocean is considerably larger than previously described.

This paper presents the first by-catch assessment focussed on mobulid rays in pelagic longline fisheries based on on-board scientific observer data (1998)(1999)(2000)(2001)(2002)(2003)(2004)(2005)(2006)(2007)(2008)(2009)(2010)(2011)(2012)(2013) over the south-western Atlantic. Mobulid diversity, as well as their catch distribution and disposition, were investigated. Mobulid by-catch frequency was low, but by-catch probability increased at lower bottom depths (i.e. continental shelf and slope), higher fishing effort and during the warm period (summer-autumn). Photographic and video records allowed the identification of two devil ray species, the spinetail devil ray (Mobula japanica) and the bentfin devil ray (Mobula thurstoni), but the number of species interacting with longliners in the region could also be greater. Southernmost captures of both species (368S) exceed previous reported records by almost 128, therefore greatly expanding their known distribution ranges towards southern waters in the south-western Atlantic. Mobulids were never retained on board, and most of them were released alive. However, hooks were often not removed from their bodies and on several occasions fishermen caused injuries while trying to cut the branch line, so some uncertainty remains regarding their post-capture mortality. More specific studies that assess these particular aspects are needed to better understand the potential effect of longline fisheries on mobulid populations.

The shortfin mako is one of the most important shark species caught in Atlantic Ocean pelagic fisheries. Given increasing concerns for the stock status of the species, the present study was designed to fill gaps in the knowledge of habitat use and movement patterns of shortfin mako in the Atlantic Ocean. From 2015 to 2019, 53 shortfin makos were tagged with pop-up satellite archival tags within the North, Central, and Southwest Atlantic Ocean, with successful transmissions received from 34 tags. Generally, sharks tagged in the Northwest and Central Atlantic moved away from tagging sites showing low to no apparent residency patterns, whereas sharks tagged in the Northeast and Southwest Atlantic spent large periods of time near the Canary Archipelago and Northwest Africa, and over shelf and oceanic waters off southern Brazil and Uruguay, respectively. These areas showed evidence of site fidelity and were identified as possible key areas for shortfin mako. Sharks spent most of their time in temperate waters (18–22°C) above 90 m; however, data indicated the depth range extended from the surface down to 979 m, in water temperatures ranging between 7.4 and 29.9°C. Vertical behavior of sharks seemed to be influenced by oceanographic features, and ranged from marked diel vertical movements, characterized by shallower mean depths during the night, to yo-yo diving behavior with no clear diel pattern observed. These results may aid in the development of more informed and efficient management measures for this species.

The Portuguese dogfish Centroscymnus coelolepis is a wide‐ranging deep‐water shark and a common by‐catch component of the catches of several mid‐ to deep‐water fisheries. In the present study, two new records from the south‐western Atlantic Ocean are reported based on specimens caught by bottom‐longline fishing vessels operating in the Argentinean–Uruguayan Common Fishing Zone. Species identification based on morphology and detailed morphometrics, as well as molecular data are presented for one of the specimens. The distribution of the species over the south‐western Atlantic is discussed on the basis of the available bibliography and a thorough revision of museum collections. The records presented here expand the species' previously acknowledged distribution southwards, from around 21° S to at least 38° S, suggesting it occurs continuously along the shelf break of eastern South America. However, given the limited access to specimens of deep‐water sharks in the region, the abundance and real extent of C. coelolepis distribution in the south‐western Atlantic as well as its interaction with deep‐water fisheries remain to be fully assessed.