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The annual counts of large whale entanglements (including serious injury and mortalities) were analyzed and used to assess the effectiveness of the Atlantic Large Whale Take Reduction Plan. Fishing gear entanglements related to the annual number of mortality events averaged 2.5 for right whales (Eubalaena glacialis), 5.6 for humpback (Megaptera novaeangliae), 0.6 for fin whales (Balaenoptera physalus) and 2.4 for minke whales (B. acutorostrata).

A state-space model, using the Jolly-Seber assumption about population entry, was used to characterize the changing abundance of North Atlantic right whales (Eubalaena glacialis) between 1990 and 2015. Estimates from this modeling approach were only slightly higher than published values, except for the most recent years (capture rates substantially declined). North Atlantic right whale abundance increased about 2.8%/annually from the median estimate of 270 individuals in 1990 to 483 in 2010, followed by a decline to 458 in 2015.

Photographic data on body and skin condition, blowhole cyamids and rake marks were used to evaluate the health of North Atlantic right whales (Eubalaena glacialis) from 1980-2008. A hierarchical Bayesian model was applied to the data to estimate demographic groups, underlying health status conditions and the population to characterize health patterns and temporal trends. Visual health scores (0-100 scale) (N=48,560) were used to estimate the health of 622 identified right whales on a monthly basis. Most whales’ health scores fluctuated between 70 and 90.

The fecal glucocorticoid metabolites (fGC) concentrations from right whales (Eubalaena glacialis) chronically entangled in fishing gears or live stranded were compared to right whales quickly killed by vessels and healthy right whales. The study aimed to characterize fGC responses to acute vs. chronic stress. fGCs in entangled whales and stranded whales were significantly higher than in whales killed by vessels and healthy whales. Serum cortisol and corticosterone in a live stranded whale were much higher than values reported in other cetaceans.

The kinematics of a tagged entangled North Atlantic right whale, before, during and after disentanglement were examined. Three sets of gear attached to a load-cell tensiometer at multiple speeds were used to calculate additional drag forces and energetic demand. Tag analyses revealed significant increases in dive depths and duration; ascent, descent and fluke stroke rates; and decreases in rot mean square fluke amplitude were significantly greater than in the non-entangled case.

This study evaluated drag characteristics of entangled North Atlantic right whales, contextualized gear drag measurements for individual whales and quantified the benefits of partial disentanglement. A load cell was used to measure drag forces on 15 sets of fishing gear removed from entangled right whales, a towed satellite telemetry buoy and 200 m of polypropylene line as it was shored to 25 m, as they were towed behind a vessel at -0.77, 1.3 and 2.1 m/s and 0, 3 and 6 m depth. Information suggests that on average entanglements increase drag and propulsive power by 1.47 fold.

Standardized external injury assessments were used to investigate the relative importance of direct anthropogenic and natural threats to northwest Atlantic leatherback turtles (Dermochelys coriacea). The information was used to assess whether the susceptibility to these threats varies between low latitude nesting and high latitude foraging region, by size and sex. Leatherback turtles foraging off the coast of Nova Scotia and at nesting sites in Trinidad were sampled. Combined, 62% showed characteristic marking associated with one injury.

The effects of hook soak time on targeted reef fish and shark bycatch were investigated in the eastern Gulf of Mexico bottom longline fishery. Hook timers were used to evaluate capture time and catch per unit effort (CPUE) for the target species, red grouper (Epinephelus morio). The results indicate the typical duration of hook soak times is longer than needed to efficiently harvest red grouper. Reducing soak time to less than one hour would result in minimal to no reduction and CPUE of red grouper.

The effects of hook soak time on targeted reef fish and shark bycatch were investigated in the eastern Gulf of Mexico bottom longline fishery. Hook timers were used to evaluate capture time and catch per unit effort (CPUE) for the target species, red grouper (Epinephelus morio). The results indicate the typical duration of hook soak times is longer than needed to efficiently harvest red grouper. Reducing soak time to less than one hour would result in minimal to no reduction and CPUE of red grouper.

Key pelagic shark species are caught in the North Pacific by Japanese longline fisheries as bycatch. These species include blue shark (Prionace glauca) and shortfin mako (Isurus oxyrinchus). In this study, fishery-independent data was leveraged by utilizing a generalized linear mixed model to standardize these data and identify changes in spatio-temporal catch rates. For blue shark, catch was recorded from temperate waters of the western and central North Pacific.

Direct interactions between longline fisheries and many top predators such as toothed whales result in substatial impacts on fishing activity; depredating species and fish stocks. These issues continue to be a growing concern in fisheries worldwide, including the French Patagonian toothfish fishery. In this field study, researchers deployed data loggers on killer whales and sperm whales while aboard commercial toothfish demersal longline fishing vessels to gain insight into when, where and how depredation occurs.

In 2015, NPF Industry Pty Ltd launched the Northern Prawn Fishery’s Bycatch Strategy 2015-2018 with the vision to reduce small bycatch by 30% in three years. A key component of the strategy was industry innovation and through this process the Kon’s Covered Fisheyes Bycatch Reduction Device (BRD) was developed.In 2016, at-sea testing of the Kon’s Covered Fisheyes Bycatch Reduction Device (BRD) was conducted in the Gulf of Carpentaria to determine its effectiveness in reducing small bycatch in the tiger prawn fishery compared to a currently legislated device.

Mobulid rays are distributed worldwide in tropical and warm temperate waters, and are landed as bycatch in many different fisheries. Five mobulid species (Mobula birostris, M. japanica, M.munkiana, M.

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 challange. In this study, scientists developed bycatch reducer devices and alternative fishing gears to mitigate the impact of demersal fishing gears on seaturtles.

Penguins are one of the most threatened groups of seabirds, with 10 of the world’s 18 species listed as Vulnerable or Endangered on the IUCN Red List. At-sea threats, such as the bycatch of penguins in fishing gear has been the subject of few directed studies and has not been fully assessed. In this literature review, researchers assess which species and fishing gear are largest contributers to penguins globally.

Fishing-related seabird mortalities are considered the most pervasive threat to seabird conservation status. Specifically, warp wire interactions (warp strike) and net captures of trawl vessels in Australia’s Commonwealth-managed Southern and Eastern Scalefish and Shark fisheries has been identified as a growing concern. This paper describes an industry-led study that developed and tested the effectiveness of 2 experimental mitigation devices for trawl vessels: a "baffler" and a "water sprayer".

Although counting nesting females and nests has been widely used to assess sea turtle abundance, surveys of in-water populations can provide a more effective means of measuring the success of recovery actions. Here, the bycatch of turtles recorded in observer data from fishing trips in the Pamlico-Albemarle Estuarine Complex, North Carolina, in 1995−1997, 2001−2003, and 2007−2009 was leveraged to idenitfy changes in species composition and overall abundance throughut the three different fishing periods.

This study investigated the effect of acoustic pingers on the behavior of Burmeister's porpoise (Phocoena spinipinnis) in the vicinity of the Peruvian small-scale driftnet fleet. Over a 4-yr period (2009-2012), 116 control (without pingers) and 94 experimental (with pingers) fishing sets were observed, and porpoise acoustic activity around nets was recorded using passive acoustic loggers (C-PODs). In regions of preferred habitat associated with cooler (17-18 C), shallow waters (within the 100 m.

1,700 lbf prototypes were developed and tested both in a lab and at sea to determine their fishing practicality. Use of these ropes have been documented as a strategy for reducing the incidence and severity of large whale entanglements in lobster pot buoy lines. Additionally, modeling work was carried out to assess the tensions placed on ropes when hauling gear in normal fishing operations and to evaluate what forces a whale might put on gear during an entanglement.

The Pacific hake (Merluccius productus) midwater trawl fishery is the largest groundfish fishery off the U.S. West Coast by volume. However, bycatch of Chinook salmon can be an issue as Endangered Species Act (ESA)-listed Evolutionarily Significant Units represent a portion of the total Chinook salmon bycatch. This study investigated the influence of artificial illumination on Chinook salmon behavior and their escapement out of a bycatch reduction device (BRD) in a Pacific hake midwater trawl.