Pub Date : 2019-08-29DOI: 10.20944/preprints201908.0306.v1
M. Jaffa
Salmon farming has been blamed for the collapse of the sea trout (Salmo trutta) fishery in Loch Maree on Scotland’s west coast despite the absence of any direct evidence. Stocks of west coast demersal marine fish, especially around the Clyde Estuary have also declined over a similar time span. The decline of these marine fish stocks can be attributed to the removal of the “three-mile fishing limit” in 1984 by UK Government legislation. Sea trout inhabit the same inshore waters as targeted demersal fish and can be caught as by-catch. Comparisons of the decline of demersal species and the sea trout from Loch Maree and the west coast show a high degree of correlation. Stocks of whiting (Merlangius merlangus) from inshore waters have found to consist of small fish which mirrors the stock makeup of the Loch Maree sea trout stock.
{"title":"Concurrent Collapses of Demersal Fish and Sea Trout (Salmo trutta) on Scotland’s West Coast Following the Removal of the “Three-Mile Fishing Limit”","authors":"M. Jaffa","doi":"10.20944/preprints201908.0306.v1","DOIUrl":"https://doi.org/10.20944/preprints201908.0306.v1","url":null,"abstract":"Salmon farming has been blamed for the collapse of the sea trout (Salmo trutta) fishery in Loch Maree on Scotland’s west coast despite the absence of any direct evidence. Stocks of west coast demersal marine fish, especially around the Clyde Estuary have also declined over a similar time span. The decline of these marine fish stocks can be attributed to the removal of the “three-mile fishing limit” in 1984 by UK Government legislation. Sea trout inhabit the same inshore waters as targeted demersal fish and can be caught as by-catch. Comparisons of the decline of demersal species and the sea trout from Loch Maree and the west coast show a high degree of correlation. Stocks of whiting (Merlangius merlangus) from inshore waters have found to consist of small fish which mirrors the stock makeup of the Loch Maree sea trout stock.","PeriodicalId":262559,"journal":{"name":"Aquaculture and Fisheries Studies","volume":"7 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-08-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115124408","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}
Glauco Favot, M. E. Cunha, H. Quental-Ferreira, M. Serrão
The cultivation of macroalgae in earth ponds could provide an optimal control on both quantity and quality of biomass. In previous studies the genus Ulva has proved to be an ideal candidate for growing in fish ponds since it withstands their considerable environmental fluctuations. This study assessed the biomass production and the SGR (specific growth rate) of green algae Ulva sp. cultivated in earth ponds facing the Ria Formosa lagoon (Southern Portugal). The growth and production performance were tested among: a) two different multitrophic systems (IMTA (fish +oyster + Ulva) and ‘Fish + Ulva’); b) four different initial densities (15 ,30, 50 e 60 g/m2); c) five production and harvest cycles (6, 7, 8, 9 e 15 days). The Specific Growth Rate (SGR) of Ulva sp. was found to be significantly different between the two multitrophic systems (p <0.05) and higher in the ‘Fish + Ulva’ system (19.3 ± 0.08% day-1) than in the IMTA system (16.7 ± 0.8% day-1). Also, there were significant differences between different densities and varied cultivating periods. Growth of Ulva sp. was dependent on both densities and time periods. The densities of 30g/m2 revealed to be the best among the four tested densities (23 ± 3.9 % day−1) whereas the optimal cultivating period was between seven and nine days (≈21 % day−1). The experiments on the production cycle indicated an optimal period of cultivation of about 8 days.
在土池中培养大型藻类可以对生物量的数量和质量进行最优控制。在以前的研究中，乌尔瓦属已被证明是鱼塘中生长的理想候选者，因为它能承受相当大的环境波动。本研究评估了在葡萄牙南部Ria Formosa泻湖的土池中养殖的绿藻Ulva sp.的生物量产量和特定生长率。试验了两种不同的多营养系统(IMTA(鱼+牡蛎+ Ulva)和“鱼+ Ulva”)的生长和生产性能;B)四种不同的初始密度(15、30、50和60 g/m2);C)五个生产和收获周期(6,7,8,9和15天)。两种多营养系统中Ulva sp.的特定生长率(SGR)差异显著(p <0.05)，“Fish + Ulva”系统的SGR(19.3±0.08%)高于IMTA系统的SGR(16.7±0.8%)。不同密度、不同栽培年限间也存在显著差异。乌尔瓦氏菌的生长与密度和时间有关。在4个试验密度中，30g/m2为最佳密度(23±3.9% day - 1)，最佳培养时间为7 ~ 9 d(≈21% day - 1)。生产周期试验表明，最佳栽培期为8天左右。
{"title":"Production of Ulva Sp. in Multitrophic Aquaculture in Earth Ponds","authors":"Glauco Favot, M. E. Cunha, H. Quental-Ferreira, M. Serrão","doi":"10.31038/afs.2019111","DOIUrl":"https://doi.org/10.31038/afs.2019111","url":null,"abstract":"The cultivation of macroalgae in earth ponds could provide an optimal control on both quantity and quality of biomass. In previous studies the genus Ulva has proved to be an ideal candidate for growing in fish ponds since it withstands their considerable environmental fluctuations. This study assessed the biomass production and the SGR (specific growth rate) of green algae Ulva sp. cultivated in earth ponds facing the Ria Formosa lagoon (Southern Portugal). The growth and production performance were tested among: a) two different multitrophic systems (IMTA (fish +oyster + Ulva) and ‘Fish + Ulva’); b) four different initial densities (15 ,30, 50 e 60 g/m2); c) five production and harvest cycles (6, 7, 8, 9 e 15 days). The Specific Growth Rate (SGR) of Ulva sp. was found to be significantly different between the two multitrophic systems (p <0.05) and higher in the ‘Fish + Ulva’ system (19.3 ± 0.08% day-1) than in the IMTA system (16.7 ± 0.8% day-1). Also, there were significant differences between different densities and varied cultivating periods. Growth of Ulva sp. was dependent on both densities and time periods. The densities of 30g/m2 revealed to be the best among the four tested densities (23 ± 3.9 % day−1) whereas the optimal cultivating period was between seven and nine days (≈21 % day−1). The experiments on the production cycle indicated an optimal period of cultivation of about 8 days.","PeriodicalId":262559,"journal":{"name":"Aquaculture and Fisheries Studies","volume":"4 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116924503","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}
two Abstract An analysis of nutrient flow, based on nitrogen (N) and phosphorous (P), was conducted on an integrated rabbit–fish–rice system (IRFR) system at the Rwasave Fish Farming Station (National University of Rwanda). Rabbits, stocked at 12 per are (1200 rabbits.ha -1 ) of pond, were reared over fishponds stocked with one and three male tilapia ( Oreochromis niloticus) per m 2 for pond treatments PT1 and PT2. Effluent fertilised by the rabbits was drawn away from the ponds by pipes installed at the bottom of the ponds to irrigate rice ( Oryza sativa L., variety Yuni Yin4 ) fields . There were six 400 m 2 ponds and nine 90 m 2 rice fields; three of the latter were irrigated by canal water and fertilised by NPK (200 kg.ha -1 .crop -1 , 2 applications; 100 kg.ha -1 .crop -1 , one application). The results showed that rabbit droppings supplied about 27% N and 79% P of the total N and P inputs, fertilising the ponds at a rate of 3.98 kg N and 1.94 kg P.ha -1 .d -1 . The fish recovered 18.5-7.6% N and 16.9-34.3% P of the total nitrogen (TN) and total phosphorus (TP) inputs. All water quality variables remained within good limits for tilapia aquaculture and nutrient distribution was not dependent on fish density. Large amounts of N and P accumulated in the water, sediment, and effluent fertilised rice fields at a higher rate (118.5 kg N and 27.2 kg P.ha -1 .d -1 ) than that of inorganic fertilizers, resulting in a slightly higher rice yield than that induced by NPK and urea. Tilapia effluent was thus able to substitute inorganic fertilisers completely, allowing savings to the farmers, and showing its potential as a fertiliser for fish and crop production rather than waste to be discharged, polluting the environment by its solids and organic matter component. Further studies involving a thorough analysis of nutrients lost and diversified uses of the nutrient-rich effluent are needed.
以卢旺达国立大学Rwasave养鱼站的兔-鱼-稻一体化系统(IRFR)为研究对象，进行了以氮(N)和磷(P)为基础的养分流动分析。兔子，以每只12只的价格饲养(1200只兔子)。在PT1和PT2池塘处理下，每平方米饲养1条和3条罗非鱼(Oreochromis niloticus)。由兔子施肥的废水通过安装在池塘底部的管道从池塘中抽出，用于灌溉水稻(Oryza sativa L.，品种Yuni Yin4)田地。有6个400米2的池塘和9个90米2的稻田;其中3个采用渠水灌溉，施用200 kg氮磷钾。Ha -1 .crop -1, 2次应用;100公斤。Ha -1 .crop -1，一次应用)。结果表明，兔粪提供了27%的N和79%的P，以3.98 kg N和1.94 kg P / ha -1 .d -1的速率施肥。鱼对总氮(TN)和总磷(TP)输入的18.5 ~ 7.6%的N和16.9 ~ 34.3%的P进行了回收。罗非鱼养殖的所有水质变量保持在良好的范围内，营养成分分布不依赖于鱼密度。大量氮和磷在水、沉积物和废水中积累，以比无机肥料更高的速率(118.5 kg N和27.2 kg p.a ha -1 .d -1)施肥稻田，导致水稻产量略高于氮磷钾和尿素。因此，罗非鱼废水能够完全替代无机肥料，为农民节省开支，并显示出其作为鱼类和作物生产肥料的潜力，而不是排放废物，因为其固体和有机物成分污染了环境。需要进行进一步的研究，包括对流失的营养物进行彻底分析和对富含营养物的废水进行多样化利用。
{"title":"Nutrient Flow in an Integrated Rabbit–Fish–Rice System in Rwanda","authors":"Rukera Tabaro, O. Mutanga, J. Micha","doi":"10.31038/afs.2021324","DOIUrl":"https://doi.org/10.31038/afs.2021324","url":null,"abstract":"two Abstract An analysis of nutrient flow, based on nitrogen (N) and phosphorous (P), was conducted on an integrated rabbit–fish–rice system (IRFR) system at the Rwasave Fish Farming Station (National University of Rwanda). Rabbits, stocked at 12 per are (1200 rabbits.ha -1 ) of pond, were reared over fishponds stocked with one and three male tilapia ( Oreochromis niloticus) per m 2 for pond treatments PT1 and PT2. Effluent fertilised by the rabbits was drawn away from the ponds by pipes installed at the bottom of the ponds to irrigate rice ( Oryza sativa L., variety Yuni Yin4 ) fields . There were six 400 m 2 ponds and nine 90 m 2 rice fields; three of the latter were irrigated by canal water and fertilised by NPK (200 kg.ha -1 .crop -1 , 2 applications; 100 kg.ha -1 .crop -1 , one application). The results showed that rabbit droppings supplied about 27% N and 79% P of the total N and P inputs, fertilising the ponds at a rate of 3.98 kg N and 1.94 kg P.ha -1 .d -1 . The fish recovered 18.5-7.6% N and 16.9-34.3% P of the total nitrogen (TN) and total phosphorus (TP) inputs. All water quality variables remained within good limits for tilapia aquaculture and nutrient distribution was not dependent on fish density. Large amounts of N and P accumulated in the water, sediment, and effluent fertilised rice fields at a higher rate (118.5 kg N and 27.2 kg P.ha -1 .d -1 ) than that of inorganic fertilizers, resulting in a slightly higher rice yield than that induced by NPK and urea. Tilapia effluent was thus able to substitute inorganic fertilisers completely, allowing savings to the farmers, and showing its potential as a fertiliser for fish and crop production rather than waste to be discharged, polluting the environment by its solids and organic matter component. Further studies involving a thorough analysis of nutrients lost and diversified uses of the nutrient-rich effluent are needed.","PeriodicalId":262559,"journal":{"name":"Aquaculture and Fisheries Studies","volume":"49 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116754373","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}
There are 19 native fish species in Lake Kinneret [1,2] of which 6 are endemic, 2 are extinct, 5 are intentional and non-intentional introductions, and 10 under commercial exploitation and of the commercial species, Sarotherodon galilaeus (Arabic: Musht Abiad; Hebrew: Amnoon HaGalil; Common: Galilee St. Peter Fish) [1-6] and the stocked mugilids [2,3,7] have the highest market value. The silver carp (introduced), bleaks (native), the common carp (nonintentionally invasion), Barbus spp, and 3 other tilapia species have lower market values (Tables 1 and 2) [8].
Kinneret湖有19种本地鱼类[1,2]，其中6种为特有种，2种已灭绝，5种为有意或无意引进，10种为商业开发，其中商业种为Sarotherodon galilaeus(阿拉伯语:Musht Abiad;希伯来语:Amnoon HaGalil;常见的:加利利圣彼得鱼(Galilee St. Peter Fish)[1-6]和放养的mugilids[2,3,7]具有最高的市场价值。鲢鱼(引进)、白鲢(本地)、鲤鱼(非故意入侵)、Barbus spp和其他3种罗非鱼的市场价值较低(表1和表2)[8]。
{"title":"Biennial (2007/8) Crisis of Sarotherodon galilaeus Fishery in Lake Kinneret (Israel): A Synopsis","authors":"M. Gophen","doi":"10.31038/afs.2021325","DOIUrl":"https://doi.org/10.31038/afs.2021325","url":null,"abstract":"There are 19 native fish species in Lake Kinneret [1,2] of which 6 are endemic, 2 are extinct, 5 are intentional and non-intentional introductions, and 10 under commercial exploitation and of the commercial species, Sarotherodon galilaeus (Arabic: Musht Abiad; Hebrew: Amnoon HaGalil; Common: Galilee St. Peter Fish) [1-6] and the stocked mugilids [2,3,7] have the highest market value. The silver carp (introduced), bleaks (native), the common carp (nonintentionally invasion), Barbus spp, and 3 other tilapia species have lower market values (Tables 1 and 2) [8].","PeriodicalId":262559,"journal":{"name":"Aquaculture and Fisheries Studies","volume":"62 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123517862","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}
{"title":"A Short Note on Climate Change: An Alternative View","authors":"","doi":"10.31038/afs.2021331","DOIUrl":"https://doi.org/10.31038/afs.2021331","url":null,"abstract":"","PeriodicalId":262559,"journal":{"name":"Aquaculture and Fisheries Studies","volume":"17 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131077666","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}
tests used of and equality The differences between using by Abstract In the study, changes in biochemical composition of warty crabs, Eriphia verrucosa between female and male individuals after the reproductive period were evaluated. The warty crabs used as study material were freshly obtained from fishermen after the breeding season (end of July). According to the data obtained in the study where the female and male individuals were evaluated separately, the average moisture, crude protein, crude lipid and crude ash contents in female E. verrucosa were 77.89%, 20.96%, 0.91% and 2.66%, respectively. In male E. verrucosa , it was found to be 76.30%, 21.44%, 0.79% and 2.47%, respectively. In the study, it was determined that the difference between male and female individuals in crude protein and crude lipid values was significant (p<0.05). Although the crude protein content was low in females, the crude lipid content was found to be higher. In other words, it was determined that while the protein ratio decreases in female individuals after the reproductive period, the lipid ratio increases. This suggests that the energy lost due to ovulation during the reproductive period may have been met by the accumulation of fat in the body.
{"title":"Biochemical Composition of Warty Crab (Eriphia verrucosa) in the Post-reproductive Period in the Black Sea","authors":"S. Dernekbaşı, İ. Karayücel, S. Karayücel","doi":"10.31038/afs.2021322","DOIUrl":"https://doi.org/10.31038/afs.2021322","url":null,"abstract":"tests used of and equality The differences between using by Abstract In the study, changes in biochemical composition of warty crabs, Eriphia verrucosa between female and male individuals after the reproductive period were evaluated. The warty crabs used as study material were freshly obtained from fishermen after the breeding season (end of July). According to the data obtained in the study where the female and male individuals were evaluated separately, the average moisture, crude protein, crude lipid and crude ash contents in female E. verrucosa were 77.89%, 20.96%, 0.91% and 2.66%, respectively. In male E. verrucosa , it was found to be 76.30%, 21.44%, 0.79% and 2.47%, respectively. In the study, it was determined that the difference between male and female individuals in crude protein and crude lipid values was significant (p<0.05). Although the crude protein content was low in females, the crude lipid content was found to be higher. In other words, it was determined that while the protein ratio decreases in female individuals after the reproductive period, the lipid ratio increases. This suggests that the energy lost due to ovulation during the reproductive period may have been met by the accumulation of fat in the body.","PeriodicalId":262559,"journal":{"name":"Aquaculture and Fisheries Studies","volume":"6 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124918351","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}
Fish fauna of the river Ravi and its some tributaries in and from earlier and present survey from Ranjit Sagar dam to Kathour, Pathankot, Punjab, including Kathua district, has revealed the presence of 97 fish species belonging to 8 orders, 18 families and 53 genera. Among various orders, there is dominance of Cypriniformes (54 spp.) followed by Siluriformes (26 species), Percformes (9 species), Synbranchiformes (3 species), Osteoglossiformes (2 species) and Clupeiformes, Salmoniformes and Beloniformes (1 species, each). The list also includes a new record of Ailia punctata and Clupisoma naziri (reported earlier from Pakistan) for Punjab state and Union territory of Jammu and Kashmir. Salmo trutta fario noticed in Sewa River is also included in the present list. Like other Indian states, fish fauna is rapidly declining due to overfishing, fishing during monsoon breeding and illegal fishing methods (Dynamiting, electric shocking, poisoning etc.). Conservation status based on IUCN observations has also been discussed.
{"title":"Fish Fauna of the River Ravi and Its Some Tributaries with a New Record of Ailia puncata and Clupisoma naziri for Punjab State and Union Territory of Jammu and Kashmir, India","authors":"Dutta Sps","doi":"10.31038/afs.2021312","DOIUrl":"https://doi.org/10.31038/afs.2021312","url":null,"abstract":"Fish fauna of the river Ravi and its some tributaries in and from earlier and present survey from Ranjit Sagar dam to Kathour, Pathankot, Punjab, including Kathua district, has revealed the presence of 97 fish species belonging to 8 orders, 18 families and 53 genera. Among various orders, there is dominance of Cypriniformes (54 spp.) followed by Siluriformes (26 species), Percformes (9 species), Synbranchiformes (3 species), Osteoglossiformes (2 species) and Clupeiformes, Salmoniformes and Beloniformes (1 species, each). The list also includes a new record of Ailia punctata and Clupisoma naziri (reported earlier from Pakistan) for Punjab state and Union territory of Jammu and Kashmir. Salmo trutta fario noticed in Sewa River is also included in the present list. Like other Indian states, fish fauna is rapidly declining due to overfishing, fishing during monsoon breeding and illegal fishing methods (Dynamiting, electric shocking, poisoning etc.). Conservation status based on IUCN observations has also been discussed.","PeriodicalId":262559,"journal":{"name":"Aquaculture and Fisheries Studies","volume":"156 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121302769","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}
In Icelandic waters the green sea urchin (Strongylocentrotus droebachiensis) is the only targeted urchin species. It is common around Iceland but its distribution is very pachy. Harvesting started in 1983 by divers which was not economically feasible and stopped in 1989. In 1993 the fishing started again and now by dredging and peaked in 1994 when 1 500 tonnes were landed. After that the fishery diclined extremely and stopped 1997. More than half of the catches in these years came from Breiðafjörður west Iceland, but the fishery was conducted wiedly. In 2004 exploitation of the stock started again and now only in Breiðafjörður. The landings were minimal (<50 t) until 2007 when it reached 134 tonn. Since then the landings have been 130-400 tonn [1]. The main fishery has alway been in the the southern part of Breiðafjörður and focused on small hot spots. Since 1993 sea urchins have only been harvested by dredging but the selectivity and efficiency of the dredges used in Iceland is unknown.
{"title":"Stock Assessment of the Green Sea Urchin (Strongylocentrotus droebachiensis) in Southern Breiðafjörður West Iceland","authors":"G. Thorarinsdóttir","doi":"10.31038/afs.2021323","DOIUrl":"https://doi.org/10.31038/afs.2021323","url":null,"abstract":"In Icelandic waters the green sea urchin (Strongylocentrotus droebachiensis) is the only targeted urchin species. It is common around Iceland but its distribution is very pachy. Harvesting started in 1983 by divers which was not economically feasible and stopped in 1989. In 1993 the fishing started again and now by dredging and peaked in 1994 when 1 500 tonnes were landed. After that the fishery diclined extremely and stopped 1997. More than half of the catches in these years came from Breiðafjörður west Iceland, but the fishery was conducted wiedly. In 2004 exploitation of the stock started again and now only in Breiðafjörður. The landings were minimal (<50 t) until 2007 when it reached 134 tonn. Since then the landings have been 130-400 tonn [1]. The main fishery has alway been in the the southern part of Breiðafjörður and focused on small hot spots. Since 1993 sea urchins have only been harvested by dredging but the selectivity and efficiency of the dredges used in Iceland is unknown.","PeriodicalId":262559,"journal":{"name":"Aquaculture and Fisheries Studies","volume":"11 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123160147","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}
The non-native fish impact assessment and native fish stock management in respect of ecosystem function, biodiversity, recruitment pattern and fish stock, presently disputing both environmental executives (e.g. policy maker/government) and scientific communities especially in riverine sector and other large water bodies in developing countries [1-4]. Non-native species may become invasive and are capable of decreasing biodiversity through competition, spreading exotic diseases, predation and habitat degradation, genetic deterioration of wild populations through hybridization and gene introgression in short or long course of time [5-8]. Non-native fish species are also responsible for reduction of fish lenght, damage breeding ground and change food web structure and population structure of indigenous fish species and also earlier introduced fish species [9-13].
{"title":"Invasion Potential, Impact and Population Structure of Non-native Fish Species, Cyprinus carpio (Linnaeus, 1758) from the Tributary of the Ganga River, Central India","authors":"N. Mishra, A. Dwivedi, P. Mayank","doi":"10.31038/afs.2021332","DOIUrl":"https://doi.org/10.31038/afs.2021332","url":null,"abstract":"The non-native fish impact assessment and native fish stock management in respect of ecosystem function, biodiversity, recruitment pattern and fish stock, presently disputing both environmental executives (e.g. policy maker/government) and scientific communities especially in riverine sector and other large water bodies in developing countries [1-4]. Non-native species may become invasive and are capable of decreasing biodiversity through competition, spreading exotic diseases, predation and habitat degradation, genetic deterioration of wild populations through hybridization and gene introgression in short or long course of time [5-8]. Non-native fish species are also responsible for reduction of fish lenght, damage breeding ground and change food web structure and population structure of indigenous fish species and also earlier introduced fish species [9-13].","PeriodicalId":262559,"journal":{"name":"Aquaculture and Fisheries Studies","volume":"302 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115863989","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}
Anomalous specimens of Tor tor and Tor putitora were noticed among fish collections made by fishermen from the river Chenab in Pargwal Wetland area, Akhnoor, over a period of three years, and are reported. Morphologically these deformed fishes were truncated and showed displacement of fins. Radiological analysis exhibited truncated vertebral column and compressed vertebrae with reduced vertebral thickness and intervertebral spaces. A possible cause of these aberrations is fast currents in various Himalayan tributaries of the torrential river Chenab in which Tor generally breeds.
{"title":"Some Deformed Specimens of Tor tor (Ham.-Buch.) and Tor putitora (Ham.-Buch.) from the Torrential River Chenab, An Important Himalayan River, Draining Union Territory of the Jammu and Kashmir, India","authors":"Dutta Sps","doi":"10.31038/afs.2021313","DOIUrl":"https://doi.org/10.31038/afs.2021313","url":null,"abstract":"Anomalous specimens of Tor tor and Tor putitora were noticed among fish collections made by fishermen from the river Chenab in Pargwal Wetland area, Akhnoor, over a period of three years, and are reported. Morphologically these deformed fishes were truncated and showed displacement of fins. Radiological analysis exhibited truncated vertebral column and compressed vertebrae with reduced vertebral thickness and intervertebral spaces. A possible cause of these aberrations is fast currents in various Himalayan tributaries of the torrential river Chenab in which Tor generally breeds.","PeriodicalId":262559,"journal":{"name":"Aquaculture and Fisheries Studies","volume":"88 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128381585","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}
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