Pub Date : 2013-10-02DOI: 10.1080/10641262.2013.799391
Jonathan S. F. Lee, E. P. Tezak, B. Berejikian
Preliminary experiments that optimize release methods pave the way to larger-scale releases and proper evaluation methods. One evaluation method is before-after-control-impact, which requires that more animals remain at release areas (“site fidelity” to impact areas) than disperse to control areas. This study tested whether there are release methods that maximize fidelity to the release area and minimize dispersal to nearby areas, which might enable a before-after-control-impact experiment. Lingcod that were 17-months old at release showed greater fidelity to release areas (23% remaining one year after release) than lingcod that were 9- and 11-months old at release. None of the 17- and 21-month-old release groups were detected on more distant structured habitats 44 weeks after release, but 8% and 13% of lingcod from the 9- and 11-month-old release groups were detected at distant structured habitat. Thus, releasing 17-month-old lingcod maximized fidelity to the release area and minimized dispersal to other areas. Differences in fidelity and dispersal rates among release-age groups may reflect ontogenetic changes in dispersal and habitat use patterns that have also been reported for wild lingcod. These behavioral similarities with wild lingcod also suggest that hatchery lingcod have potential to interact and integrate with wild lingcod in nature.
{"title":"Ontogenetic Changes in Dispersal and Habitat Use in Hatchery-Reared Lingcod","authors":"Jonathan S. F. Lee, E. P. Tezak, B. Berejikian","doi":"10.1080/10641262.2013.799391","DOIUrl":"https://doi.org/10.1080/10641262.2013.799391","url":null,"abstract":"Preliminary experiments that optimize release methods pave the way to larger-scale releases and proper evaluation methods. One evaluation method is before-after-control-impact, which requires that more animals remain at release areas (“site fidelity” to impact areas) than disperse to control areas. This study tested whether there are release methods that maximize fidelity to the release area and minimize dispersal to nearby areas, which might enable a before-after-control-impact experiment. Lingcod that were 17-months old at release showed greater fidelity to release areas (23% remaining one year after release) than lingcod that were 9- and 11-months old at release. None of the 17- and 21-month-old release groups were detected on more distant structured habitats 44 weeks after release, but 8% and 13% of lingcod from the 9- and 11-month-old release groups were detected at distant structured habitat. Thus, releasing 17-month-old lingcod maximized fidelity to the release area and minimized dispersal to other areas. Differences in fidelity and dispersal rates among release-age groups may reflect ontogenetic changes in dispersal and habitat use patterns that have also been reported for wild lingcod. These behavioral similarities with wild lingcod also suggest that hatchery lingcod have potential to interact and integrate with wild lingcod in nature.","PeriodicalId":49627,"journal":{"name":"Reviews in Fisheries Science","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2013-10-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/10641262.2013.799391","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"59680668","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2013-10-02DOI: 10.1080/10641262.2013.836446
Y. Miyakoshi, M. Nagata, S. Kitada, M. Kaeriyama
The hatchery program for chum salmon in Hokkaido, northern Japan, constitutes one of the largest salmon hatchery programs in the world. The hatchery program has been conducted for over 120 years, and returns of chum salmon rapidly increased during the last quarter of the 20th century. Since the 1990s, chum salmon returns to Hokkaido have remained at a historically high level, although different fluctuation trends have been observed among regions within Hokkaido. Although such intensive hatchery programs have been conducted for more than 25 generations, there has been no evidence indicating any decline of genetic diversity. The hatchery program for chum salmon in Hokkaido is successful in increasing commercial catches and will likely be the main management tool in future. However, information on naturally spawning chum salmon in Hokkaido remains scarce. Assessment of naturally spawning populations recently commenced, and it has been revealed that naturally spawning chum salmon populations remain in many rivers in Hokkaido. For future management, monitoring chum salmon of both hatchery and natural origin is important, and a novel strategy that accounts for the enhancement of commercial stocks and the coexistence of hatchery programs and wild populations should be established in Japan.
{"title":"Historical and Current Hatchery Programs and Management of Chum Salmon in Hokkaido, Northern Japan","authors":"Y. Miyakoshi, M. Nagata, S. Kitada, M. Kaeriyama","doi":"10.1080/10641262.2013.836446","DOIUrl":"https://doi.org/10.1080/10641262.2013.836446","url":null,"abstract":"The hatchery program for chum salmon in Hokkaido, northern Japan, constitutes one of the largest salmon hatchery programs in the world. The hatchery program has been conducted for over 120 years, and returns of chum salmon rapidly increased during the last quarter of the 20th century. Since the 1990s, chum salmon returns to Hokkaido have remained at a historically high level, although different fluctuation trends have been observed among regions within Hokkaido. Although such intensive hatchery programs have been conducted for more than 25 generations, there has been no evidence indicating any decline of genetic diversity. The hatchery program for chum salmon in Hokkaido is successful in increasing commercial catches and will likely be the main management tool in future. However, information on naturally spawning chum salmon in Hokkaido remains scarce. Assessment of naturally spawning populations recently commenced, and it has been revealed that naturally spawning chum salmon populations remain in many rivers in Hokkaido. For future management, monitoring chum salmon of both hatchery and natural origin is important, and a novel strategy that accounts for the enhancement of commercial stocks and the coexistence of hatchery programs and wild populations should be established in Japan.","PeriodicalId":49627,"journal":{"name":"Reviews in Fisheries Science","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2013-10-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/10641262.2013.836446","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"59681151","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2013-10-02DOI: 10.1080/10641262.2013.812503
A. Hart, Lachlan W. S. Strain, F. Fabris, Jamin Brown, M. Davidson
A cohort of Haliotis laevigata, spawned from wild broodstock, was monitored from settlement at a hatchery until age 8. Animals were released into the wild at 31 mm (± 4 SD), targeting an enhancement size-class of 135–145-mm shell length. Release densities were tailored to match wild-stock densities using a size-dependent mortality model. A total of 7,500 animals were released into 24 sites, and each site was precisely mapped to control release densities. Environmental and husbandry factors were also quantified. Initial survival rates (six months post-release) differed significantly among sites (range: 11–67%) but not beyond this time period. Legal minimum length (140 mm) was achieved, on average, at 5 years of age or 3.5 years post-release, and the cohort entered the fishery over 3 years (age 5–8). Cumulative survival at age 5 varied between 20% at the better sites and 6% at the worst sites, with an average of 13%. Water depth was significantly positively correlated with growth (r = 0.47; p < 0.05), but no other ecological variables influenced growth or survival. Husbandry factors were implicated in sites with poor survival, but this was not confirmed statistically. The cohort successfully entered the fishery and was harvested at an overall fishing mortality (F) of 0.27, but site differences in F were significant and highly correlated with growth.
{"title":"Stock Enhancement in Greenlip Abalone Part I: Long-Term Growth and Survival","authors":"A. Hart, Lachlan W. S. Strain, F. Fabris, Jamin Brown, M. Davidson","doi":"10.1080/10641262.2013.812503","DOIUrl":"https://doi.org/10.1080/10641262.2013.812503","url":null,"abstract":"A cohort of Haliotis laevigata, spawned from wild broodstock, was monitored from settlement at a hatchery until age 8. Animals were released into the wild at 31 mm (± 4 SD), targeting an enhancement size-class of 135–145-mm shell length. Release densities were tailored to match wild-stock densities using a size-dependent mortality model. A total of 7,500 animals were released into 24 sites, and each site was precisely mapped to control release densities. Environmental and husbandry factors were also quantified. Initial survival rates (six months post-release) differed significantly among sites (range: 11–67%) but not beyond this time period. Legal minimum length (140 mm) was achieved, on average, at 5 years of age or 3.5 years post-release, and the cohort entered the fishery over 3 years (age 5–8). Cumulative survival at age 5 varied between 20% at the better sites and 6% at the worst sites, with an average of 13%. Water depth was significantly positively correlated with growth (r = 0.47; p < 0.05), but no other ecological variables influenced growth or survival. Husbandry factors were implicated in sites with poor survival, but this was not confirmed statistically. The cohort successfully entered the fishery and was harvested at an overall fishing mortality (F) of 0.27, but site differences in F were significant and highly correlated with growth.","PeriodicalId":49627,"journal":{"name":"Reviews in Fisheries Science","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2013-10-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/10641262.2013.812503","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"59681400","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2013-10-02DOI: 10.1080/10641262.2013.812506
A. Hart, Lachlan W. S. Strain, S. Hesp
This study presents a bioeconomic evaluation of the effect of stock enhancement on biomass, net present value, profitability, and gross value of product of the Australian greenlip abalone (Haliotis laevigata) fishery. Enhancement targets were defined as a function of natural recruitment (Nr) and compared with current harvest strategies. The model was conditioned on a Western Australian fishery, then applied to greenlip stocks throughout Australia. Two levels of releases (50% Nr and 100% Nr) at varying fishing mortality (F), size at harvest, and size at release were evaluated in detail. Model validation was also undertaken by comparing the model-derived spawning biomass (SSb) with an alternative estimate (SSbf) obtained using in-water surveys and a different growth model. Economic profitability and increased spawning biomass were achieved for most stock enhancement scenarios, and optimal profitability occurred with a 10–20% decrease in F from current levels, a 10% decrease in minimum legal length, and an annual enhancement of Nr juveniles to match natural recruitment. More radical scenarios, such as an annual release of 150% Nr combined with a 30% decrease in size at harvest resulted in greater profitability (+175%) but presented a higher risk of wild stocks being replaced with hatchery genotypes. Sensitivity analysis revealed that mortality, size at release, and harvest price were the critical parameters, while costs of production and fishing were less important. At the national scale, an enhancement scenario involving an annual release of 6.1 million 4-cm juveniles (∼age 2) resulted in a 60% increase in gross value of product ($25 to $40 million), a 120% increase in profitability ($12 to $26 million), and net present value ($190 to $420 million; 6% discount), and a 25% increase in SSb.
{"title":"Stock Enhancement in Greenlip Abalone Part III: Bioeconomic Evaluation","authors":"A. Hart, Lachlan W. S. Strain, S. Hesp","doi":"10.1080/10641262.2013.812506","DOIUrl":"https://doi.org/10.1080/10641262.2013.812506","url":null,"abstract":"This study presents a bioeconomic evaluation of the effect of stock enhancement on biomass, net present value, profitability, and gross value of product of the Australian greenlip abalone (Haliotis laevigata) fishery. Enhancement targets were defined as a function of natural recruitment (Nr) and compared with current harvest strategies. The model was conditioned on a Western Australian fishery, then applied to greenlip stocks throughout Australia. Two levels of releases (50% Nr and 100% Nr) at varying fishing mortality (F), size at harvest, and size at release were evaluated in detail. Model validation was also undertaken by comparing the model-derived spawning biomass (SSb) with an alternative estimate (SSbf) obtained using in-water surveys and a different growth model. Economic profitability and increased spawning biomass were achieved for most stock enhancement scenarios, and optimal profitability occurred with a 10–20% decrease in F from current levels, a 10% decrease in minimum legal length, and an annual enhancement of Nr juveniles to match natural recruitment. More radical scenarios, such as an annual release of 150% Nr combined with a 30% decrease in size at harvest resulted in greater profitability (+175%) but presented a higher risk of wild stocks being replaced with hatchery genotypes. Sensitivity analysis revealed that mortality, size at release, and harvest price were the critical parameters, while costs of production and fishing were less important. At the national scale, an enhancement scenario involving an annual release of 6.1 million 4-cm juveniles (∼age 2) resulted in a 60% increase in gross value of product ($25 to $40 million), a 120% increase in profitability ($12 to $26 million), and net present value ($190 to $420 million; 6% discount), and a 25% increase in SSb.","PeriodicalId":49627,"journal":{"name":"Reviews in Fisheries Science","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2013-10-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/10641262.2013.812506","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"59681440","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2013-10-02DOI: 10.1080/10641262.2013.796813
M. D. Taylor, Andrew V. Fairfax, I. Suthers
The dynamics of fish behavior, migration, and habitat use following stock enhancement will influence the outcome of recovery programs and indicate the ecological limits of the system. This study tested the effect of release density on emigration, activity patterns, and space utilization by releasing juvenile mulloway (Sciaenidae: Argyrosomus japonicus) at low and high densities and monitoring movement intensively for 336 h post release. Mulloway released at high densities had faster emigration and greater overall emigration rates than low density releases. Also, mulloway released at high densities used sub-optimal habitats at a greater frequency. Released fish dispersed into habitat patches at densities proportional to the quality of the habitat patch, consistent with density-dependent habitat selection. Targeting releases of small numbers of fish to the carrying capacity of individual patches of habitat will contribute to the success and economic viability of release programs in open systems. Releases of high densities of individuals or repeated releases at the same site may lead to increased emigration and losses from the stocked system. The capacity of a target habitat to support released fish can be rapidly assessed using pilot releases and intensive monitoring of acoustically tagged fish, prior to the implementation of large-scale release programs.
{"title":"The Race for Space: Using Acoustic Telemetry to Understand Density-Dependent Emigration and Habitat Selection in a Released Predatory Fish","authors":"M. D. Taylor, Andrew V. Fairfax, I. Suthers","doi":"10.1080/10641262.2013.796813","DOIUrl":"https://doi.org/10.1080/10641262.2013.796813","url":null,"abstract":"The dynamics of fish behavior, migration, and habitat use following stock enhancement will influence the outcome of recovery programs and indicate the ecological limits of the system. This study tested the effect of release density on emigration, activity patterns, and space utilization by releasing juvenile mulloway (Sciaenidae: Argyrosomus japonicus) at low and high densities and monitoring movement intensively for 336 h post release. Mulloway released at high densities had faster emigration and greater overall emigration rates than low density releases. Also, mulloway released at high densities used sub-optimal habitats at a greater frequency. Released fish dispersed into habitat patches at densities proportional to the quality of the habitat patch, consistent with density-dependent habitat selection. Targeting releases of small numbers of fish to the carrying capacity of individual patches of habitat will contribute to the success and economic viability of release programs in open systems. Releases of high densities of individuals or repeated releases at the same site may lead to increased emigration and losses from the stocked system. The capacity of a target habitat to support released fish can be rapidly assessed using pilot releases and intensive monitoring of acoustically tagged fish, prior to the implementation of large-scale release programs.","PeriodicalId":49627,"journal":{"name":"Reviews in Fisheries Science","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2013-10-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/10641262.2013.796813","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"59680572","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2013-10-02DOI: 10.1080/10641262.2013.799389
B. Green, Hugh Pederson, C. Gardner
Translocation, sea ranching, and assisted migration are under scrutiny as methods to augment populations so that harvests can be increased or populations can better adapt to changing environmental conditions. Understanding the ecological effects of any such environmental manipulation is critical to its successful application. One potential ecological effect of any type of stock enhancement is the displacement of either resident or released groups such that finding shelter or foraging habitat is adversely affected. This study examined behavioral interactions of resident and translocated Jasus edwardsii rock lobster after an introduction of 1,961 “small pale” phenotypic morphs to an area populated by the resident “large red” phenotypic morph. This translocation was an experimental stock enhancement conducted as part of a larger study to increase the yield and value of the fishery. Most translocated individuals established a home range within a couple of days of release (generally <2), and these ranges were generally less than 1.0 ha in size. Home-range kernels and foraging ranges overlapped between the two morphs, and there was no evidence of avoidance (Jacob's cohesion index 0.01, Z = 1.06, p = 0.28). This case of translocation for stock enhancement between ecotypes had no detectable adverse effect on either the resident or the translocated population, and in this species, stock enhancement could become part of an integrated conservation and harvest optimization strategy.
作为增加种群数量的方法，迁移、海上牧场和辅助迁移正在接受审查，以便增加收成或使种群更好地适应不断变化的环境条件。了解任何此类环境操纵的生态影响对其成功应用至关重要。任何种类的种群增加的一个潜在的生态影响是迁离居住或放归的种群，从而对寻找庇护所或觅食生境产生不利影响。本研究在将1961种“小苍白”表型型的爱德华螯虾引入到“大红色”表型型的居住区域后，研究了居住和易位的爱德华螯虾的行为相互作用。这种易位是一项实验性的种群增加，是增加渔业产量和价值的更大研究的一部分。大多数迁移个体在释放后的几天内(一般小于2天)建立了一个家园范围，这些范围的大小通常小于1.0公顷。两个变种的家核区和觅食区存在重叠，不存在回避现象(Jacob’s cohesion index 0.01, Z = 1.06, p = 0.28)。在这种情况下，种群数量增加在生态型之间的易位对居住种群和易位种群都没有明显的不利影响，在该物种中，种群数量增加可以成为综合保护和收获优化策略的一部分。
{"title":"Overlap of Home Ranges of Resident and Introduced Southern Rock Lobster after Translocation","authors":"B. Green, Hugh Pederson, C. Gardner","doi":"10.1080/10641262.2013.799389","DOIUrl":"https://doi.org/10.1080/10641262.2013.799389","url":null,"abstract":"Translocation, sea ranching, and assisted migration are under scrutiny as methods to augment populations so that harvests can be increased or populations can better adapt to changing environmental conditions. Understanding the ecological effects of any such environmental manipulation is critical to its successful application. One potential ecological effect of any type of stock enhancement is the displacement of either resident or released groups such that finding shelter or foraging habitat is adversely affected. This study examined behavioral interactions of resident and translocated Jasus edwardsii rock lobster after an introduction of 1,961 “small pale” phenotypic morphs to an area populated by the resident “large red” phenotypic morph. This translocation was an experimental stock enhancement conducted as part of a larger study to increase the yield and value of the fishery. Most translocated individuals established a home range within a couple of days of release (generally <2), and these ranges were generally less than 1.0 ha in size. Home-range kernels and foraging ranges overlapped between the two morphs, and there was no evidence of avoidance (Jacob's cohesion index 0.01, Z = 1.06, p = 0.28). This case of translocation for stock enhancement between ecotypes had no detectable adverse effect on either the resident or the translocated population, and in this species, stock enhancement could become part of an integrated conservation and harvest optimization strategy.","PeriodicalId":49627,"journal":{"name":"Reviews in Fisheries Science","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2013-10-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/10641262.2013.799389","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"59680656","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2013-10-02DOI: 10.1080/10641262.2013.800785
M. Walsh, H. Fujimoto, Takeo Yamamoto, Tatsuya Yamada, Yoichi Takahashi, Y. Yamashita
Conditioning is the process of providing individuals reared for stock enhancement with some degree of “natural” experience prior to release. Conditioning flatfish in predator-free cages may help adjustment to the wild. From 2008–2010, the Obama Laboratory conducted pre-release, experimental cage conditioning for Japanese flounder in both the Takahama and Obama portions of Wakasa Bay, Japan. Recaptured fish were acquired through a cooperative effort between researchers and local fishermen. The objectives were to describe how characteristics of released flounder changed with cage exposure and to determine how recapture rates compared between conditioned and non-conditioned fish. Significantly more conditioned fish were recaptured than non-conditioned fish in Obama Bay in 2010 (p < 0.05). In 2008 and 2009, recapture rates of conditioned and non-conditioned flounder followed the same trend, although these were not significantly different. Laboratory experiments revealed that conditioned fish had significantly better burying abilities (p < 0.001) and enhanced feeding abilities compared to non-conditioned fish. This study is the first to examine flatfish conditioning strategies using market data and shows that cage conditioning can favorably alter the attributes and recapture rates of released fish.
{"title":"Post-Release Performance and Assessment of Cage-Conditioned Japanese Flounder, Paralichthys olivaceus, in Wakasa Bay, Japan","authors":"M. Walsh, H. Fujimoto, Takeo Yamamoto, Tatsuya Yamada, Yoichi Takahashi, Y. Yamashita","doi":"10.1080/10641262.2013.800785","DOIUrl":"https://doi.org/10.1080/10641262.2013.800785","url":null,"abstract":"Conditioning is the process of providing individuals reared for stock enhancement with some degree of “natural” experience prior to release. Conditioning flatfish in predator-free cages may help adjustment to the wild. From 2008–2010, the Obama Laboratory conducted pre-release, experimental cage conditioning for Japanese flounder in both the Takahama and Obama portions of Wakasa Bay, Japan. Recaptured fish were acquired through a cooperative effort between researchers and local fishermen. The objectives were to describe how characteristics of released flounder changed with cage exposure and to determine how recapture rates compared between conditioned and non-conditioned fish. Significantly more conditioned fish were recaptured than non-conditioned fish in Obama Bay in 2010 (p < 0.05). In 2008 and 2009, recapture rates of conditioned and non-conditioned flounder followed the same trend, although these were not significantly different. Laboratory experiments revealed that conditioned fish had significantly better burying abilities (p < 0.001) and enhanced feeding abilities compared to non-conditioned fish. This study is the first to examine flatfish conditioning strategies using market data and shows that cage conditioning can favorably alter the attributes and recapture rates of released fish.","PeriodicalId":49627,"journal":{"name":"Reviews in Fisheries Science","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2013-10-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/10641262.2013.800785","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"59681266","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2013-10-02DOI: 10.1080/10641262.2013.837364
B. Chin, M. Nakagawa, T. Noda, T. Wada, Y. Yamashita
The effects of release habitat on the effectiveness of stocking were evaluated in Miyako Bay, Iwate, Japan. Hatchery-reared black rockfish juveniles were released at four different stations characterized by different habitat conditions from 2002–2007, and a survey was conducted of landed fish at Miyako Fish Market. Growth rate and feeding condition of wild and released juveniles sampled from two known wild nursery areas (Stn. 1 and Stn. 2) were also examined to elucidate the conditions that form optimal habitat. Comparisons of growth and feeding condition of juveniles between Stn. 1 and Stn. 2 indicated that Stn. 1, with its brackish waters, seagrass beds, abundant mysids, and large gammarids, supported better growth and survival of released fish, which in turn led to a higher market return rate. The highest market return rate was estimated as 8.3% (for 45-mm total length juveniles released at Stn. 1 in 2007), corresponding to a maximum economic return rate (value of recaptured fish divided by hatchery and release costs) of 1.32.
{"title":"Determining Optimal Release Habitat for Black Rockfish, Sebastes schlegelii: Examining Growth Rate, Feeding Condition, and Return Rate","authors":"B. Chin, M. Nakagawa, T. Noda, T. Wada, Y. Yamashita","doi":"10.1080/10641262.2013.837364","DOIUrl":"https://doi.org/10.1080/10641262.2013.837364","url":null,"abstract":"The effects of release habitat on the effectiveness of stocking were evaluated in Miyako Bay, Iwate, Japan. Hatchery-reared black rockfish juveniles were released at four different stations characterized by different habitat conditions from 2002–2007, and a survey was conducted of landed fish at Miyako Fish Market. Growth rate and feeding condition of wild and released juveniles sampled from two known wild nursery areas (Stn. 1 and Stn. 2) were also examined to elucidate the conditions that form optimal habitat. Comparisons of growth and feeding condition of juveniles between Stn. 1 and Stn. 2 indicated that Stn. 1, with its brackish waters, seagrass beds, abundant mysids, and large gammarids, supported better growth and survival of released fish, which in turn led to a higher market return rate. The highest market return rate was estimated as 8.3% (for 45-mm total length juveniles released at Stn. 1 in 2007), corresponding to a maximum economic return rate (value of recaptured fish divided by hatchery and release costs) of 1.32.","PeriodicalId":49627,"journal":{"name":"Reviews in Fisheries Science","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2013-10-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/10641262.2013.837364","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"59681302","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2013-10-02DOI: 10.1080/10641262.2013.838075
Edward V. Camp, K. Lorenzen, R. Ahrens, L. Barbieri, K. Leber
In this study, an integrative review of the potential for stock enhancement is conducted to support desirable management outcomes in marine recreational fisheries, focusing on the Florida, USA, red drum fishery as a case study. Here, stock enhancement is implicitly seen as a way of simultaneously achieving both ecological objectives of sustained wild fish populations and socioeconomic objectives of high fishing effort and/or catch rates. However, the review suggests that a fundamental tradeoff remains between these objectives in the short-term because stocking of hatchery fish is likely to result in at least partial displacement of wild fish through biological interactions as well as increased fishing pressure. Contrary to the perception of enhancement as a “quick fix,” successful use of the approach in the marine recreational fishery is likely to require sophisticated stock management and some adaptation in governance. In developing the enhancement, it will be necessary to address uncertainty in key attributes, specifically dynamics of recruitment, angler-effort responses, and stakeholder involvement. This may be achieved by combining quantitative modeling, monitoring, and stocking experiments in an active adaptive management framework to consider enhancement in the context of alternative management strategies. It is suggested that any interim enhancement should minimize ecological risk per socioeconomic benefit by stocking larger fish in areas where high fishing mortality limits abundance of wild fish. These conclusions are largely generalizable to other recreational enhancements, and this work serves as a model of rarely published a priori enhancement evaluation.
{"title":"Potentials and Limitations of Stock Enhancement in Marine Recreational Fisheries Systems: An Integrative Review of Florida's Red Drum Enhancement","authors":"Edward V. Camp, K. Lorenzen, R. Ahrens, L. Barbieri, K. Leber","doi":"10.1080/10641262.2013.838075","DOIUrl":"https://doi.org/10.1080/10641262.2013.838075","url":null,"abstract":"In this study, an integrative review of the potential for stock enhancement is conducted to support desirable management outcomes in marine recreational fisheries, focusing on the Florida, USA, red drum fishery as a case study. Here, stock enhancement is implicitly seen as a way of simultaneously achieving both ecological objectives of sustained wild fish populations and socioeconomic objectives of high fishing effort and/or catch rates. However, the review suggests that a fundamental tradeoff remains between these objectives in the short-term because stocking of hatchery fish is likely to result in at least partial displacement of wild fish through biological interactions as well as increased fishing pressure. Contrary to the perception of enhancement as a “quick fix,” successful use of the approach in the marine recreational fishery is likely to require sophisticated stock management and some adaptation in governance. In developing the enhancement, it will be necessary to address uncertainty in key attributes, specifically dynamics of recruitment, angler-effort responses, and stakeholder involvement. This may be achieved by combining quantitative modeling, monitoring, and stocking experiments in an active adaptive management framework to consider enhancement in the context of alternative management strategies. It is suggested that any interim enhancement should minimize ecological risk per socioeconomic benefit by stocking larger fish in areas where high fishing mortality limits abundance of wild fish. These conclusions are largely generalizable to other recreational enhancements, and this work serves as a model of rarely published a priori enhancement evaluation.","PeriodicalId":49627,"journal":{"name":"Reviews in Fisheries Science","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2013-10-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/10641262.2013.838075","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"59681353","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
京公网安备 11010802042870号
京ICP备2023020795号-1
扫码关注我们
求助内容：
应助结果提醒方式：