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Management agencies have increasingly relied on size limits, daily bag or trip limits, quotas, and seasonal closures to manage fishing in recreational and commercial fisheries. Another trend is to establish aquatic protected areas, including no-take reserves (NTRs), to promote sustainable fisheries and protect aquatic ecosystems. Some anglers, assuming that no serious harm befalls the fish, advocate allowing catch-and-release (C&R) angling in aquatic protected areas. The ultimate success of these regulations and C&R angling depends on ensuring high release survival rates by minimizing injury and mortality. To evaluate the potential effectiveness of these practices, we review trends in C&R fishing and factors that influence release mortality. Analysis of Marine Recreational Fishery Statistic Survey (MRFSS) data for 1981–1999 showed no statistically significant U.S. trends for total number of anglers (mean 7.7 × 106), total catch in numbers (mean 362 × 106), or total annual catch/angler (mean 42.6 fish). However, mean total annual landings declined 28% (188.5 to 135.7 × 106), mean total catch/angler/trip declined 22.1% (0.95 to 0.74 fish), and mean landings/angler/trip declined 27% (0.42 to 0.31 fish). The total number of recreational releases or discards increased 97.1% (98.0 to 193.2 × 106) and as a proportion of total catch from 34.2% in 1981 to 58.0% in 1999. Evidence indicates that the increased releases and discards are primarily in response to mandatory regulations and to a lesser extent, voluntary releases. Total annual catch and mean annual catch/angler were maintained despite declines in catch per trip because anglers took 30.8% more fishing trips (43.5 to 56.9 × 106), perhaps to compensate for greater use of bag and size limits. We reviewed 53 release mortality studies, doubling the number of estimates since Muoneke and Childress (1994) reviewed catch and release fishing. A meta-analysis of combined data (n=274) showed a skewed distribution of release mortality (median 11%, mean 18%, range 0–95%). Mortality distributions were similar for salmonids, marine, and freshwater species. Mean mortality varied greatly by species and within species, anatomical hooking location was the most important mortality factor. Other significant mortality factors were: use of natural bait, removing hooks from deeply hooked fish, use of J-hooks (vs. circle hooks), deeper depth of capture, warm water temperatures, and extended playing and handling times. Barbed hooks had marginally higher mortality than barbless hooks. Based on numbers of estimates, no statistically significant overall effects were found for fish size, hook size, venting to deflate fish caught at depth, or use of treble vs. single hooks. Catch and release fishing is a growing and an increasingly important activity. The common occurrence of release mortality, however, requires careful evaluation for achieving fishery management goals and in some cases, disturbance, injury, or mortality may conflict with some goals of NTRs. Research is needed to develop better technology and techniques to reduce release mortality, to assess mortality from predation during capture and after release, to determine cumulative mortality from multiple hooking and release events, and to measure sub-lethal effects on behavior, physical condition, growth, and reproduction.
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... The practice has grown significantly globally, presumably driven by dwindling fish stocks, stricter regulations and an increasing conservation ethic amongst recreational angler groups (Arlinghaus et al., 2020;Pollock and Pine, 2007). However, despite its use as a conservation measure, C&R angling can cause considerable physiological and physical stress to target fishes and may result in significant post-release mortality (Bartholomew and Bohnsack, 2005;Bower et al., 2016a;Danylchuk et al., 2014;Suski et al., 2007). ...
... collated in Brownscombe et al., 2017). As such, C&R studies have been conducted on a variety of different species in a vast range of environments and have illustrated how the impacts of C&R vary dramatically, being both species-, fisheryand context-specific (Bartholomew and Bohnsack, 2005;Brownscombe et al., 2017;Cooke and Suski, 2005). Over time, standard methodologies have become commonplace within C&R angling experiments and tests of physical impairment, physiological stress, behavioural response and post-release mortality are most often used to quantify the response of fishes within organised 'rapid assessments' Bartholomew and Bohnsack, 2005;Gagne et al., 2017;Lennox et al., 2015). ...
... As such, C&R studies have been conducted on a variety of different species in a vast range of environments and have illustrated how the impacts of C&R vary dramatically, being both species-, fisheryand context-specific (Bartholomew and Bohnsack, 2005;Brownscombe et al., 2017;Cooke and Suski, 2005). Over time, standard methodologies have become commonplace within C&R angling experiments and tests of physical impairment, physiological stress, behavioural response and post-release mortality are most often used to quantify the response of fishes within organised 'rapid assessments' Bartholomew and Bohnsack, 2005;Gagne et al., 2017;Lennox et al., 2015). ...
Argyrosomus japonicus is arguably South Africa’s most important estuarine recreational and small-scale fishery species. Although juvenile A. japonicus predominate in estuarine environments, where catch-and-release angling is common, limited C&R studies have taken place. The aim of this study was to use angler-behaviour to robustly examine the physiological stress response, reflex impairment and short-term (12–36-hour) survival of A. japonicus following C&R angling. Observations of estuarine recreational angling informed three air exposure treatments based on minimum (10 s), mean (75 s) and maximum (240 s) observed times, for use in a controlled angling experiment. Based on a prior laboratory study, blood sampling was delayed 30–40 min post-capture to allow for peak accumulations of lactate and glucose. Long air exposure (240 s) predicted significantly higher blood glucose concentrations (ANOVA, p = 0.03) than short (10 s) exposure. Similarly, both long (p = 0.01) and moderate (75 s; p = 0.01) air exposure significantly predicted elevated blood lactate concentrations, when compared with short exposure. In terms of physical impairment, long air exposure (240 s) had a significant negative influence on the reflex response (cumulative link model, p = 0.01) of A. japonicus. An observed short-term mortality of 7.7% was primarily attributed to hooking injury. To reduce significant physiological and physical stress, it is proposed that anglers should aim to reduce air exposure times to below the observed mean of 75 s, and ideally to 10 s. For relevant and meaningful future C&R studies, we propound the incorporation of angler behavioural assessments, and the investigation of physiological stress responses, prior to designing field studies.
... Severe hooking injuries have been shown to impede fish survival. This is especially true when deep hooking occurs and results in internal esophageal and/or organ tissue damage (e.g., gills, stomach) (Arlinghaus et al., 2007;Bartholomew and Bohnsack, 2005;Cooke et al., 2012;Muoneke and Childress, 1994;Schaefer, 1989). While we were unable to assess any long-lasting sublethal impacts (e.g., feeding impairment) from hooking injury, of the 50 trials in this study, only one GT (2%) was documented as a potential mortality after losing its equilibrium at and after release, and this fish was deeply hooked near the gills. ...
... Although predator density was low in the selected study site and depredation for GT was not observed, if predator burdens become high, GT may be susceptible to predation events regardless of their resiliency to the effects of C&R angling. Further, considering activity levels for fly angled GT were suppressed for several minutes after release, they could also be vulnerable to post-release mortality if greater physical injury and sub-lethal impacts occur (Bartholomew and Bohnsack, 2005). For example, Danylchuk et al. (2007) documented that for bonefish (Albula vulpes) that lost equilibrium, often corresponding to air exposure duration, were six times more likely to be predated than those that did not lose equilibrium. ...
Giant trevally (Caranx ignobilis, GT) are growing in popularity as a target for tourism-based recreational fisheries throughout their range in the Indo-Pacific. Although predominately catch-and-release (C&R), to date there is no species-specific scientific evidence to support capture and handling guidelines. As such, we examined how GT caught via fly fishing gear while in shallow water responded to capture and handling in the Alphonse Island Group, Republic of the Seychelles. Specifically, we evaluated the physical injury for GTs captured via fly fishing gear, as well as their reflex impairment and post-release activity (using tri-axial accelerometer biologgers) following three air exposure treatments (0 s, 15 s, 30 s). We also had a reference treatment where GTs were caught and landed quickly via a handline, and not exposed to air (0 s) prior to release. Hooking location for both gear types was predominately the jaw or corner of the mouth (fly fishing, n = 30; 83.3%; handline; n = 12, 85.7%), but one fish hooked in a critical location for each capture gear. Across all treatments, only one fish (2%) in the handline treatment was considered a potential short-term post-release mortality following being deeply hooked in the gills and subsequently losing equilibrium upon release. GT reflex impairment and overall post-release activity measured via overall dynamic body acceleration were not influenced by fight time and air exposure treatments used in our study. For GTs across all treatments, locomotor activity was lower in the initial minutes following release than during the second half of the ten minute monitoring period. Overall, our study suggests that GTs in the Alphonse Island Group are resilient to being caught via fly fishing, handled, and air exposed for up to 30 s. However, given the diversity of angling locations for GTs (e.g., shallow flats, deeper reefs) and gear types (e.g., conventional tackle, lures with several treble hooks), additional assessments are needed to help act as the foundation for more universal best practices that can inform management plans for GT recreational fisheries.
... However, post-release mortality of hook-and-line caught fish is not easy to measure and can vary significantly between species and fisheries. Many factors are important, including water temperature, hooking damage, and handling (Bartholomew and Bohnsack, 2005;Brownscombe et al., 2017). Extrapolation of existing post-release mortality to other species or regions is likely to depend on the similarity of the fishing practices and environmental conditions (ICES, 2015). ...
Technical Report
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The introduction of high survivability exemptions from the EU landing obligation has raised questions on how they relate to ICES stock advice and the management of quotas (TACs). Where discard rates are high, and survival rates are limited, substantial quantities of dead discards are generated. On the other hand, high survival rates may result in limited impacts of discarding despite high discard rates. Therefore, to achieve agreed levels of fishing mortality, dead discards should be accounted for in the stock assessment and the advice derived from it. The inclusion of discard survival in stock assessments has wider application also since it can improve estimates of fishing mortality and in turn enhance scientific advice on fishing opportunities. This ICES workshop, WKSURVIVE, was established to explore and progress the inclusion of discard survival in stock assessments. Participants consisted of researchers with expertise in conducting discard survival experiments and researchers with expertise in stock assessments. The workshop successfully reviewed the approaches taken in existing ICES stocks assessments to integrate discard survival estimates. Three cases were identified: plaice (Pleuronectes platessa) in Division 7.a (Irish Sea), several Norway lobster (Nephrops norvegicus) Functional Units (FUs), andsea bass (Dicentrarchus labrax) in divisions 4.b, 4.c, 7.a, and 7.d–h (although only for recreational catches in this last case). These cases are reviewed and described in the report. WKSURVIVE identified case study ICES stock assessments for which there is management interest to include discard survival, and for each one mapped to it relevant and robust discard survival evidence. Based on the type of assessment and the associated discard survival evidence, the group agreed on recommendations on the inclusion of discard survival for each stock assessment. A table including the stock assessments, survival evidence, and stock-specific recommendations was a key output from this workshop. The group also reviewed other case studies where the implications of discard survival on stock estimates and reference points are actively being explored, but not yet used in the assessments. The workshop also included a small seminar with a series of presentations on recent and current research activity related to discard survival. Ten presentations were made and included, among others, the discard survival of Nephrops, sole, rays, and small pelagics. This continues to be an active research area and there is currently substantial attention on the discard survival of rays in particular, which links to the EU conditional survivability exemption for skates and rays and associated evidence roadmap. A summary of each area of research activity is presented here.
... Recent research has mainly focused on the mortality of catch-andrelease angling and its effect on fish populations or higher trophic levels [18][19][20], ecological and biological responses [21,22], and systematic management patterns of recreational fishing [5,[23][24][25][26]. There is a growing tendency to estimate the status of recreational fishery in various developing countries [27][28][29][30]. ...
Recreational fishing is an important component of the global capture fishery, given its significant role in the economy, social culture, and ecology. Compared to the mature development found in industrialized countries, recreational fishing in developing countries or transitional economy is a new industry with abundant jobs and high revenues. China's recreational fishery industry has shown an upward trend since 2003. This paper built an evaluation framework from both static (present competitive strength) and dynamic (potential competitive strength) perspectives to evaluate recreational fishery competitiveness in 30 Chinese provinces based on normal cloud model. The results showed the following: (1) The evaluation framework can effectively evaluate recreational fishery competitiveness. Meanwhile, there is significant randomness and fuzziness discrepancy between different indicators. 'Industry' indicators had the lowest fuzziness and randomness. (2) The development of recreational fishery competitiveness in China is not strong and uneven, with more than two-thirds of the total provinces with the lowest competitiveness level. Regarding spatial distribution, the eastern coastal provinces had relatively strong competitiveness, whereas the western inland provinces were weak. (3) There was stability divergence of competitiveness results among different grades. In general, the competitiveness of provinces belonging to grades I and V was the most stable, while other provinces are relatively unstable with the characteristics of dynamic changes. (4) The main advantageous factors for recreational fishery competitiveness in most provinces were 'service', whereas the main disadvantageous factor was 'resources'. The abundance of fishery resources might not be a key factor resulting in regional recreational fishery competitiveness discrepancies. This study can provide a reference for decision-makers to formulate an assessment framework for recreational fishery industry and provide ideas for the formulation of recreational fishery planning at the national level.
... For example, the Humphead Maori wrasse (Cheilinus undulatus) and Potato cod (Epinephelus tukula), which are both listed as protected species under the Fish Resources Management Act (1994), were both caught in low numbers by recreational fishers in one or both years of the study (Table 1). While these fish were released, post-release mortality can be high for a range of fish species (Bartholomew and Bohnsack, 2005), resulting from short and long-term effects of barotrauma (Wegner et al., 2021). Although protection of these diversity hotspots is important to conserve many individual species, it must be recognized that low diversity areas may also contain species of conservation value (Kareiva and Marvier, 2003). ...
Information on fish species diversity is important to monitor changes and maintain sustainability in multispecies fisheries. However, examination of species diversity often ignores spatial patterns, yet it is influenced by spatially structured ecological processes. Such information is important for identifying areas of high conservation value for individual species, taxonomic groups or the entire ecosystem. In this study, the spatial distribution of West Coast demersal scalefish diversity in Western Australia was characterized based on recreational fishing data collected through two off-site phone-diary surveys. Using multivariate indicator cokriging, the effect of fishing effort and measurement uncertainty was considered in the characterisation. The study found that teleost species from Families Epinephelidae, Glaucosomatidae and Sparidae were the most common, with the relative contribution of 77% and 71% to the total catch in 2011/12 and 2013/14, respectively. In addition, maps of diversity indices showed that high diversity was located at the south-central parts of the study area and increased near the coast with some patchiness at the southern part. Spatial maps can be helpful when site-specific management is aimed at maintaining a certain level of species diversity caught by recreational fishers.
... Considering the paucity of information on this subject, and differences across species in both deep hooking rates (Bartholomew & Bohnsack, 2005;Muoneke & Childress, 1994) and circle hook performance (Cooke & Suski, 2004), the primary objective of this study was therefore to evaluate straight and turned-up hook eyes on a circle hook to assess whether eye orientation affected deep hooking of bait-caught stream-dwelling trout. We included J hooks in our study design for comparative purposes, and also evaluated the relative success of landing fish with hooks having different eye orientations. ...
It has been well documented that circle hooks generally reduce deep hooking of bait‐caught fish. However, for decades there has been speculation that the hook eye must be straight relative to the shank for circle hooks to function properly, yet this aspect of hook configuration has rarely been investigated. Using a passive hook set when strikes were detected, we compared deep hooking rates and catch probability for stream‐dwelling trout (Yellowstone cutthroat trout [Oncorhynchus clarkii bouvieri Jordan & Gilbert], rainbow trout [O. mykiss Walbaum], and cutthroat trout × rainbow trout hybrids) caught using baited circle and J hooks with the eye either straight with or turned‐up from the shank. Landed fish averaged 26 cm in total length and ranged from 11 to 46 cm. Most fish (83%) were hooked either in the upper or lower jaw, but 16% were hooked deeply (i.e., either in the esophagus or the gills). As expected, the deep hooking rate was lower for circle hooks (10%) than for J hooks (24%). Logistic regression model results indicated that hook eye orientation had no effect on deep‐hooking, with deep hooking rates of 11.0% and 8.2% for circle hooks with angled‐up and straight eyes, respectively, compared to 21.7% and 25.3% for J hooks with angled‐up and straight eyes. Model results also revealed that deep hooking probability differed among anglers but did not differ between species and was not related to fish length. Catch probability (i.e., the proportion of fish strikes that resulted in a landed fish) did not differ between hooks or hook eye orientations. Contrary to some perceptions, our results suggest that changing the angle of the hook eye does not affect deep hooking rates when anglers use baited circle hooks to land stream‐dwelling trout.
... This is particularly the case for contentious issues that may draw a wide range of opinions from various user and conservation groups or issues that require fishers to change their fishing behaviour. For example, release weights have become mandatory in some jurisdictions to mitigate the impacts of barotrauma and reduce post-release mortality when fishers release undersize or unwanted fish at depth [4,[28][29][30]. Provision of information on the impacts of post-release mortality, as well as ways to reduce these impacts, has played an important role in successfully implementing change [27,[31][32][33]. ...
The loss of hooked fish from shark depredation has become an increasing problem in marine recreational fisheries worldwide, particularly among charter and private-boat recreational fishers. There is growing need to understand the prevalence of shark encounters, where depredation occurs and how recreational fishers respond to and mitigate depredation. This study of 1340 charter and private-boat recreational fishers in north-western Australia, included both probability-based (telephone and online) and opt-in (online) survey methods and is the first to document mitigation methods used by recreational fishers. More than half of the respondents (728) who completed the survey indicated that they had attempted to mitigate depredation. In the probability-based survey, the main mitigation methods reported by charter and private-boat fishers were to move spots, use wire trace or stop fishing. Depredation evokes strong opinions from some sections of the fishing population. Although more avid fishers self-selected for the opt-in surveys, the inclusion of information from these respondents, particularly from open-ended questions, provided detailed information on attitudes among fishers where this issue is of concern. This study highlights the wide range of views and concerns regarding depredation, all of which need to be considered when developing policies and guidelines around this issue. As with other contentious issues where changes in fishing behaviour are required, decision-makers will need to devise strategies to inform and educate the fishing public in how to mitigate against depredation.
We quantified effects of wind speed and sunlight on Smallmouth Bass (Micropterus dolomieu), a popular gamefish in North America, after catch‐and‐release (C&R) (n = 90) during August for various periods (0, 10, 30 and 90 s) in direct sunlight or shaded from direct sunlight. We evaluated change in skin temperature and reflex action mortality predictor (RAMP) scores. Changes in skin temperature were larger with increasing wind speeds and air exposure duration. Light intensity had no effect on skin temperature or RAMP. Generally, skin temperature decreased (i.e. colder) when wind speed exceeded ~5 km/h and increased (i.e. warmer) when wind speed was below ~5 km/h. Significantly, lower RAMP scores were associated with longer air exposure. Generally, Smallmouth Bass exposed to air for longer than 10 s were significantly more impaired prior to release. We recommend anglers reduce the time that large fish are exposed to air to reduce immediate reflex impairment.
One of the elements critical to the success of catch-and-release fisheries is the use of appropriate gear that permits releasing fish safely. To date, not all fish species have been the focus of comprehensive studies on this topic, and this applies to cyprinids. Fish from this family are distinct because of their pharyngeal teeth and the particular way they ingest food. We evaluated the impact of hook type on cyprinid catch rates (further catch per unit effort (CPUE)), the size of the fish caught, and the welfare of the fish released. Quickly assessing immediate reactions with reflex action mortality predictors (RAMP), we determined the consequences of recreational angling with barbed J-hooks, barbless J-hooks, and circle hooks. During the study, 1,066 fish were caught that belonged to eight native cyprinid species. Hook type did not have a significant impact on the fishing index with the mean CPUE ranging from 14.4 (circle hook) to 17.2 (barbed J-hook). The size of the fish caught also did not depend on hook type. However, hook type influenced the efficiency of hook removal, which was the lowest for circle hooks (45.6 %) and the highest for barbless hooks (63.7 %). Dehooking time was linked significantly with hook type, hook location, and fish species. The longest dehooking time was noted for fish caught with barbed J-hooks. Anatomical hooking locations did not differ in the fish caught with J-hooks, while the hooking location of circle hooks differed significantly in comparison to that of the J-hooks. Deep hooking in fish caught with circle hooks occurred decidedly less frequently as did tissue damage. Bleeding occurred more frequently in fish that exhibited impaired reflex action mortality predictors. Fish caught with circle hooks exhibited the least impaired reflexes. The differences in the build of the anterior part of the cyprinid digestive system and the manner in which theses fishes take up food did not exclude using circle hooks.
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The stock of the red grouper in the Campeche Bank, Southern Gulf of Mexico, is overexploited. The Mexican artisanal fleet generates the greatest contribution in the catches of the red grouper in Yucatán with a high proportion of red grouper smaller than the minimum catch size. The current regulations for the fishing management of this species indicate, among other, a minimum catch size (MCS) and a restriction on the hook size used for the capture of the red grouper, however, it has not yet been evaluated and recent studies indicate that the hooks designated for this fleet are not efficient for the TMC indicated by this regulation. Three longlines equipped each with 150 Mustad hooks of sizes # 13/0, # 14/0 and # 15/0, baited with pieces (4 and 8 cm) of Atlantic Herring (Opisthonema oglinum), were tested for capture red grouper at sites near to Celestún and Río Lagartos, inside the operation area of the artisanal fleet. A total of 1,063 fish were catched (24.2–73.8 cm Lt) between June 2016 and June 2017. Generalized Linear Models (GLM) were used to identify any effects of spatial factors (fishing area and depth stratum), technological (hook size and bait size) and biological (individuals’ size) on CPUE, size and weight of fish, the physical integrity and the catchability of the red grouper. The likelihood of damage caused by technological and spatial factors (depth stratum) on the body of red grouper individuals was also analyzed by logistic regression. The spatial factors generated an effect on CPUE. The size of the hooks and the size of the bait did not represent factors with significant effects on CPUE in number, but in weight. The size of the hooks and the size of the bait generated a significant effect on the catch size of the individuals. The average size and weight of the individuals captured was significantly greater with hook size #15/0 and with the larger size of bait. However, the size range of the individuals captured was a wide one (24 to 73 cm Lt) and the percentage of juveniles smaller than the TMC was significantly low. The most common hooked organs were the mouth and stomach. The external organs (eyes and fins) were hooked occasional. The size of the individuals, the size of the hooks and the size of the bait were factors related to the probability of hooking. Hooks # 14/0 and long bait favored insertion in the mouth. However, the probability of stomach insertion was higher for adult individuals. The most common symptoms of barotrauma were the expansion of the gas bladder and the eversion of the stomach. The expansion of the gas bladder was frequent from -25 m, depth in which some cases of stomach expulsion were observed, the frequency of this symptom was increased from 30 m deep. Both symptoms were frequent in individuals less than the TMC that were captured from 30 m deep. Fishing areas and depth, as well as the size of the hook, were the factors that represented a significant source of variation in catchability. The catchability was higher: in the eastern zone, at the deepest sites (> 20 m) and with the larger hooks (14/0 and 15/0). Bait size did not represent a factor of variation in catchability. The catchability was high for juveniles and adults without changes related to the size of the individuals. The size and depth interacted on the catchability. Juvenile were always vulnerable to fishing gear, regardless of the fishing area, depth, or size of the hook. This work represents the second study that evaluates the effect of hook size on size of fish at capture and complementary to the previous study conducted in the artisanal fishery of the red grouper at the Campeche Bank. This is the first study to analyze the effect of bait size on catch size and the one that evaluates the effect of the size of the circular hooks, the size of the bait and the depth of capture on the physical integrity of the red grouper captured in operation area of the artisanal fleet of the Yucatan coast. It is also the first to assess catchability and its variations due to the size of the circle hooks, the size of the bait and the depth based on fishery independent data.
Electronic serial mode of access: World Wide Web via the Michigan DNR, Institute for Fisheries Research site.
The fishing characteristics of circle hooks and straight shank or "J" hooks were investigated in the pelagic longline fishery during two successive trips. In one trip, circle hooks and J-hooks of comparable size were alternated along the length of the longline on six sets of approximately 400 live-baited hooks each, allowing a preliminary comparison of catch per unit effort (CPUE), hooking location, and mortality between the two hook types. On a previous trip, records of hooking location and mortality were obtained for J-hooks on nine additional longline sets. Yellow fin tuna Thunnus albacares accounted for 60% of the catch; the remainder was composed of 15 other species, none of which was represented by more than eight individuals. There was higher CPUE for all species combined, using circle hooks (5.05 fish/100 hooks) as compared with using "J" hooks (2.28 fish/100 hooks). Similar results were observed with the catch of the target species (yellowfin tuna), for which CPUE was approximately 2.5 times higher with circle hooks (3.33 tuna/100 hooks) as compared with J-hooks. Circle hooks also resulted in a lower mortality for all species (31% versus 42%) and for the target species (21 % versus 39%). For all species, 95% of the fish taken on circle hooks were hooked in the jaw. Hooking location varied by species, but for all species combined, circle hooks consistently had a higher frequency of jaw hooking and a lower frequency of gut hooking than J-hooks. These preliminary results suggest that use of circle hooks in the pelagic longline fishery targeting yellowfin tuna may not only increase CPUE and survival of this species but also improve the survival of incidental catch and bycatch.