Fisheries Research最新文献

{"title":"Best practices for common snook stock enhancement identified through iterative release experiments","authors":"Ryan W. Schloesser,&nbsp;Nathan P. Brennan,&nbsp;Paula Caldentey,&nbsp;Kenneth M. Leber","doi":"10.1016/j.fishres.2025.107540","DOIUrl":"10.1016/j.fishres.2025.107540","url":null,"abstract":"<div><div>Research on stock enhancement of Common Snook <em>Centropomus undecimalis</em> in southwest Florida has recently prioritized using passive integrated transponder (PIT) tags to monitor released fish. Autonomous antenna arrays deployed around release sites allowed for continuous sampling of PIT tagged fish, increasing post-release observations to estimate survival and establish best practices. A series of 25 iterative stocking experiments from 2015 to 2023 have generated data on 333 unique release groups (mean sizes = 112–287 mm FL) spanning a suite of stocking times, locations, and protocols. Stocking experiments were conducted with 45,958 juveniles, with ∼65 % being PIT tagged (100 % tagged for replicated studies and 10 % for larger, one-time releases). Mark-recapture models regularly indicated that survival is high and constant around 35 days post-release, providing a consistent point in time to assess experimental impacts. The diversity of stocking efforts resulted in survival rates to day 35 ranging from 0 % to 50.9 % of individuals. A step-wise modeling approach examined the spatial, temporal, and procedural factors for each unique release group to identify best practices with the goal of &gt; 20 % survival to day 35, which occurred for 68 release groups. Although low-surviving groups (&lt;10 %) can occur at any time, many were anecdotally associated with experimental designs with high-handling or stressful environmental times. We determined best practices for stocking Snook in southwest Florida to be releasing large juveniles into the mouth, lower, or middle reaches of tidal creeks in May, June, or September, using acclimation cages when stocking into locations considered to be high predation risk or environmentally stressful, and waiting an additional year between releases following a high-survival stocking event.</div></div>","PeriodicalId":50443,"journal":{"name":"Fisheries Research","volume":"291 ","pages":"Article 107540"},"PeriodicalIF":2.3,"publicationDate":"2025-09-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145158436","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Growth and life-history parameters of the high-value sea cucumber, Holothuria fuscogilva","authors":"Steven W. Purcell ,&nbsp;Lea A.F. Djenidi ,&nbsp;Hugo Denis ,&nbsp;Florian Baletaud ,&nbsp;Antoine Gilbert","doi":"10.1016/j.fishres.2025.107539","DOIUrl":"10.1016/j.fishres.2025.107539","url":null,"abstract":"<div><div>Growth rates and life-history parameters of marine animals underpin conservation planning and fishery harvest strategies yet are unknown for most sea cucumbers. The white teatfish <em>Holothuria</em> (<em>Microthele</em>) <em>fuscogilva</em>, a high-value species, is widely harvested and listed on CITES Appendix II. We used a photographic mark−recapture method to measure growth of wild white teatfish in New Caledonia. <em>Ex situ</em> measurements of the animals weakly corresponded with their <em>in situ</em> measurements. Bidimensional metrics of body size using <em>ex situ</em> measures provided the most reliable predictions of body weight. Length−weight relationships for <em>H. fuscogilva</em> varied greatly among data from New Caledonia, French Polynesia, Torres Strait (Australia) and the Coral Sea. Of 67 animals photographically marked, seven were recaptured 13 months later. Growth averaged 220 g (total whole weight) or 1.4 cm (total length) per individual. We modelled growth using the Electronic Length Frequency Analysis (ELEFAN) routine using data of all captured animals. The growth coefficient (<em>K</em>) was estimated at 0.082 y⁻¹ and natural mortality rate (<em>M</em>) was approximated at 0.19 y⁻¹. Age-at-first-sexual-maturity was estimated at 15−23 years and longevity at 57 years. While the modelling deserves caution, the data overall suggest that <em>H. fuscogilva</em> is a slow-growing species with a considerable lifespan. Management and conservation measures for teatfish sea cucumbers (subgenus <em>Microthele</em>) should be highly conservative in light of their vulnerable life-history traits.</div></div>","PeriodicalId":50443,"journal":{"name":"Fisheries Research","volume":"291 ","pages":"Article 107539"},"PeriodicalIF":2.3,"publicationDate":"2025-09-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145159260","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Influence of time-varying productivity on fishery reference points and implications for conservation objectives and management advice","authors":"Nathan E. Hebert ,&nbsp;Timothy J. Barrett ,&nbsp;Julie R. Marentette ,&nbsp;François Turcotte ,&nbsp;Brad Hubley","doi":"10.1016/j.fishres.2025.107541","DOIUrl":"10.1016/j.fishres.2025.107541","url":null,"abstract":"<div><div>Providing science advice for fisheries management generally involves estimating reference points, commonly defined in terms of a proportion of the biomass at maximum sustainable yield or unfished biomass. These reference points assume a population in equilibrium, a premise frequently challenged by the time-varying productivity observed in many fish stocks. Reference points can serve as control points in harvest control rules (HCRs) and as indicators of stock status that can trigger a rebuilding plan. The guidance for addressing time-varying productivity varies among jurisdictions (e.g., using mean productivity over a time series or recent productivity only). Fisheries and Oceans Canada (DFO) has recently identified a need for further research on time-varying reference points before providing policy guidance for use in fisheries management. In this study, we describe how individual components of productivity influence reference points using three generalized fish life-histories. We also assess the impact of alternative approaches (i.e., static vs. time-varying) to defining reference points on implied stock status (using the DFO status categories of critical, cautious, and healthy) and management advice using reference points as control points in HCRs. Using a static limit reference point (LRP) to operationalize DFO’s objective to avoid serious harm to stock productivity, we evaluate the performance of various HCRs under time-varying productivity, with control points defined via different productivity scenarios. We identify an HCR with a static biomass lower control point and a dynamic fishing mortality upper control point that has relatively high yields while maintaining a high probability of keeping the stock above the LRP. This HCR performs well across both increasing and decreasing productivity scenarios. An HCR with control points based only on recent productivity performed well under decreasing productivity only when stock biomass didn’t fall far below the LRP. We show that perceived stock status can vary from critical to healthy in a given year, depending on choice of productivity period used to define stock status reference points, implying that careful selection of such reference points is needed. There can be risks to using policy default approaches based solely on recent productivity when productivity is decreasing over time.</div></div>","PeriodicalId":50443,"journal":{"name":"Fisheries Research","volume":"291 ","pages":"Article 107541"},"PeriodicalIF":2.3,"publicationDate":"2025-09-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145158437","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The effects of ENSO on spatial-temporal distribution and growth rate of three cryptic mullet species in Taiwan","authors":"Yu-Ling Nien ,&nbsp;Nan-Jay Su ,&nbsp;Ching-Ping Lu ,&nbsp;Hsueh-Jung Lu ,&nbsp;Chia-Hui Wang","doi":"10.1016/j.fishres.2025.107538","DOIUrl":"10.1016/j.fishres.2025.107538","url":null,"abstract":"<div><div>This study investigates the impact of ENSO on the species composition and growth during the early-life history of three cryptic mullet species (NWP1–3) in the estuaries around Taiwan. Juvenile mullets were identified using genetic method, and their growth rates were analyzed using generalized additive models (GAMs) based on biological and environmental variables. The results found that NWP2 was the most abundant species, dominating several months and estuaries. NWP1 had lower abundance than NWP2, but its proportion was relatively higher in La Niña and rarer in El Niño. NWP3 exhibited the lowest abundance, but expanded spatially during El Niño. Moreover, the growth of juvenile mullet was influenced by multiple factors annually, especially sea surface temperature (SST) and drifting growth rate (DGR). The environmental changes induced by ENSO and species-specific traits simultaneously impact both the distribution and growth patterns of cryptic mullet species. Both these factors directly influence species composition and indirectly affect species abundance by modifying growth and mortality rates. Consequently, lower SST during La Niña year benefited the abundance and growth of NWP1, while higher SST during El Niño year benefited NWP3 population. Although NWP2 maintained high abundance annually, rising SST may impact the growth of this species. These findings underscore the critical role of interannual environmental variability in regulating the distribution, abundance, and growth during the early life stages of cryptic mullet species in subtropical estuarine systems.</div></div>","PeriodicalId":50443,"journal":{"name":"Fisheries Research","volume":"291 ","pages":"Article 107538"},"PeriodicalIF":2.3,"publicationDate":"2025-09-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145119265","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The use of fatty acid markers to distinguish hatchery and wild chum salmon fry and a description of post-stocking changes in fatty acid levels","authors":"Yutaka Yano,&nbsp;Koh Hasegawa,&nbsp;Kentaro Honda,&nbsp;Yuhei Ogura","doi":"10.1016/j.fishres.2025.107537","DOIUrl":"10.1016/j.fishres.2025.107537","url":null,"abstract":"<div><div>Fatty acid compositions of chum salmon (<em>Oncorhynchus keta</em>) fry were examined to distinguish between hatchery and wild fish in natural environments. Levels (%) of 18:2n-6 (linoleic acid) were significantly higher in fry obtained from a hatchery (13.0 %) than in wild fry collected in a river (2.1 %). Conversely, levels of 20:5n-3 (eicosapentaenoic acid; EPA) were significantly lower in the former (4.2 %) than in the latter (11.4 %). Differences in the levels of the two fatty acids between artificial pellets and wild fry stomach contents suggest that dietary differences caused the observed differences in fry fatty acid composition. The levels of 18:2n-6 and 20:5n-3 in hatchery fry collected in coastal waters decreased and increased, respectively, within days after stocking in the river. Furthermore, the levels became similar to those of riverine wild fry by approximately 20 days after stocking. These results indicate that the two fatty acids can be used to distinguish between hatchery and wild chum salmon fry in the natural environment. However, the period during which the two can be distinguished is limited.</div></div>","PeriodicalId":50443,"journal":{"name":"Fisheries Research","volume":"291 ","pages":"Article 107537"},"PeriodicalIF":2.3,"publicationDate":"2025-09-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145106727","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Cod highly infected with the parasitic nematode Contracaecum osculatum demonstrates stunted growth: A controlled laboratory experiment with ad libitum feeding","authors":"Jane W. Behrens ,&nbsp;Marie Plambech Ryberg ,&nbsp;Jakob Hemmer-Hansen ,&nbsp;Maria Krüger-Johnsen ,&nbsp;Anders Nielsen ,&nbsp;Niels Gerner Andersen","doi":"10.1016/j.fishres.2025.107532","DOIUrl":"10.1016/j.fishres.2025.107532","url":null,"abstract":"<div><div>Predatory fish in the wild and in particular Eastern Baltic cod <em>Gadus morhua</em> are facing varying and unpredictable feeding opportunities. This implies a high assimilative capacity including nutritional state-related hyperphagia to maintain long-term positive energy balance. Heavy infection of cod livers by the parasitic nematode <em>Contracaecum osculatum</em> is suspected to jeopardize the assimilative capacity and thus the vital rates, growth, reproduction and mortality of the cod population. We examine the effect of <em>C. osculatum</em> on growth, condition and liver weight of cod in laboratory experiments with ad libitum feeding. We find that highly infected cod displays reduced hepatosomatic index and reduced or negative growth and change in condition factor. We suggest that in the wild, cod also with lower infection levels may be constrained by an impaired liver capacity as they here also face feeding constraints. Measurements of growth hormone expression together with knowledge about the endocrine regulation of appetite and growth are used to explain the data. We find strong indications that for cod with high infection level this plays a significant role for all the three vital population rates, and that these effects should be considered in the management of the cod stock in the eastern Baltic Sea.</div></div>","PeriodicalId":50443,"journal":{"name":"Fisheries Research","volume":"291 ","pages":"Article 107532"},"PeriodicalIF":2.3,"publicationDate":"2025-09-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145107229","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Jellyfish mitigation for net-based fisheries: A qualitative systematic review","authors":"Kylie A. Pitt ,&nbsp;Clare Morrison ,&nbsp;Iain M. Suthers ,&nbsp;Michael J. Kingsford","doi":"10.1016/j.fishres.2025.107535","DOIUrl":"10.1016/j.fishres.2025.107535","url":null,"abstract":"<div><div>Jellyfish blooms pose significant challenges to net-based fisheries, causing economic losses and operational difficulties. This study reviews existing strategies and proposes novel methods for mitigating jellyfish for net-based fisheries. A systematic literature search identified 35 publications that specifically discussed jellyfish mitigation for net-based fisheries, which were categorised into coping, adapting, and transforming strategies. Coping strategies include relocating vessels to avoid jellyfish; manually removing jellyfish bycatch and repairing fishing gear; government subsidies; and processing facilities imposing financial penalties when receiving catches contaminated with jellyfish. Adapting strategies involve the use of Bycatch Reduction Devices (BRDs), reconfiguring nets, and using predictive models to provide advanced warnings of jellyfish blooms. Transformative strategies encompass attempts to remove medusae and jellyfish polyps from the environment and pivoting fisheries to harvest jellyfish. Most methods used by fishers to mitigate jellyfish have remained largely unchanged for many decades. Technological advancements, such as intelligent nets and real-time monitoring, however, are beginning to offer innovative solutions but may be prohibitively expensive for small-scale fisheries. The study highlights the need for collaboration among stakeholders to develop sustainable jellyfish mitigation strategies; and to resolve and forecast the causes of jellyfish blooms.</div></div>","PeriodicalId":50443,"journal":{"name":"Fisheries Research","volume":"291 ","pages":"Article 107535"},"PeriodicalIF":2.3,"publicationDate":"2025-09-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145106726","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Variability in the density contrast of Antarctic krill (Euphausia superba): The non-negligible importance of size, season and region","authors":"Zhuang Chen ,&nbsp;Guoping Zhu","doi":"10.1016/j.fishres.2025.107533","DOIUrl":"10.1016/j.fishres.2025.107533","url":null,"abstract":"<div><div>The acoustic method has been widely used for estimating the biomass of Antarctic krill (<em>Euphausia superba</em>), the accuracy of which is often influenced by the parameters of the acoustic scattering model. A constant g-value has been used for this model, potentially introducing biases in the estimates due to effects of ontogeny, season and region. This study investigated the g-value of krill and the effects of size, season and region on this value using the generalized additive model (GAM) and found that the g-values were significantly affected by these variables. The optimal GAM explained 57.3 % of the deviance in the krill g-values, with 'Month' contributing the largest share (24.32 % absolute, 42.43 % relative to the explained deviance). A 0.5 % change in the g-value was found to result in approximately 0.8 dB difference in target strength. This study concluded that the importance of krill standard length, region and season cannot be neglected when considering the g-value as an input parameter in acoustic estimation of krill biomass. The study further suggests that ontogenetic, regional and seasonal variation in the g-value of krill should be incorporated into acoustic biomass estimation models to improve their accuracy and support krill conservation and management efforts.</div></div>","PeriodicalId":50443,"journal":{"name":"Fisheries Research","volume":"291 ","pages":"Article 107533"},"PeriodicalIF":2.3,"publicationDate":"2025-09-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145106725","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"In situ target strength measurements of Peruvian anchovy (Engraulis ringens) from data collected by a commercial echosounder during fishing operations","authors":"Martin Santivañez-Yuffra ,&nbsp;Nathaly Pereira-Letona ,&nbsp;Cynthia Vasquez-Paredes","doi":"10.1016/j.fishres.2025.107534","DOIUrl":"10.1016/j.fishres.2025.107534","url":null,"abstract":"<div><div>Although fishing vessels have been used as opportunistic scientific platforms in the last two decades, target strength (TS) studies based on industry-collected data are still scarce. Here we present an <em>in situ</em> TS estimation of Peruvian anchovy (<em>Engraulis ringens</em>) from data recorded by a 120 kHz Simrad ES60 commercial echosounder mounted on the purse-seiner “Maru” in May-July 2017 during its fishing operations on North-Center stock area. TS-length (L) relationships (TS=a Log₁₀ (L)+b, with b= b₂₀ when a= 20) were estimated from pooled data using a curve fitting method. Influence of depth (Z) on TS was also investigated. Mean TS of 10–16.5 cm individuals was −54.2 dB (±0.2 dB) with corresponding a, b and b₂₀ values of 22.2, −79.5 dB and −77 dB. TS showed strong dependence with depth following Boyle’s law: TS= 20Log₁₀(L)-6.4Log₁₀(1-Z/10)-73.3 dB (r²=0.8). Our TS and b₂₀ estimates are in line with existing values for <em>E. ringens</em> in Perú but are lower than those published for the same species in Chile and from other members of the <em>Engraulis</em> genus. Results reported here can be used for biomass estimation during periods not covered by systematic surveys, helping to achieve near-real time monitoring of stocks.</div></div>","PeriodicalId":50443,"journal":{"name":"Fisheries Research","volume":"291 ","pages":"Article 107534"},"PeriodicalIF":2.3,"publicationDate":"2025-09-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145061038","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"New trophic insights associated with the return of a top predator, bluefin tuna, to Skagerrak and the Sound","authors":"Gustav Hellström ,&nbsp;Kim Birnie-Gauvin ,&nbsp;Petter Lundberg ,&nbsp;William Jaktén Langert ,&nbsp;Kristi Källo ,&nbsp;Lene K. Sortland ,&nbsp;Brian R. MacKenzie ,&nbsp;Jose Luis Varela ,&nbsp;Anders Koed ,&nbsp;Einar Eg Nielsen ,&nbsp;Andreas Sundelöf ,&nbsp;Hege Sande ,&nbsp;Maria Overgård ,&nbsp;Henrik Baktoft ,&nbsp;Kim Aarestrup ,&nbsp;Tomas Brodin","doi":"10.1016/j.fishres.2025.107501","DOIUrl":"10.1016/j.fishres.2025.107501","url":null,"abstract":"<div><div>This study examines the dietary composition of the recently reoccurring Atlantic bluefin tuna (ABFT, <em>Thunnus thynnus</em>) in the Skagerrak-Kattegat-Sound area of the North-East Atlantic. We analysed the stomach contents of 44 ABFT, with lengths between 232 and 295 cm (CFL), captured in August and September annually from 2020 to 2022 via rod-and-reel fishing. Our analysis identified 19 species of teleost fish, four types of squid, and one crab species, although the diet was dominated by pelagic schooling fish such as garfish (percentage of index of relative abundance (%IRI) = 22.5), herring (%IRI = 6.8), mackerel (%IRI = 6.8), and various demersal gadoid species (combined %IRI = 42). Regional variation in dietary composition between Skagerrak and the Sound indicates that ABFT exhibit foraging flexibility, primarily targeting locally abundant, energy-rich schooling fish, while occasionally consuming other prey. The prevalence of garfish in the diet, which is neither commercially targeted nor managed or regulated, highlights the importance of maintaining healthy stocks of this species for supporting the continuous return of ABFT to the area.</div></div>","PeriodicalId":50443,"journal":{"name":"Fisheries Research","volume":"291 ","pages":"Article 107501"},"PeriodicalIF":2.3,"publicationDate":"2025-09-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145050187","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}