Vestimentiferan tubeworms, once erected at a phylum level, are now known to comprise a part of the specialised deep-sea polychaete family Siboglinidae. Their widespread and abundant occurrence at hydrothermal vents and hydrocarbon seeps has fostered numerous studies of their evolution and biogeography, ecology and physiology. Harbouring autotrophic, sulphide-oxidising, intracellular bacterial symbionts, they form large populations of `primary' producers with contrasting characteristics, from fast-growing, short-living species at vents, to slow-growing, long-living species at seeps. These different life strategies and the ways they modify the biogeochemistry of their respective environments have consequences on the macro- and meiofaunal assemblages that develop within vestimentiferan bushes. New findings indicate that postlarval recruits get infected through the skin by free-living bacteria for which growth is rapidly and specifically limited by the host to mesoderm cells around the gut that further transform into the characteristic trophosome. The resulting internal location of symbionts prompts specific adaptations of the hosts to fulfil their metabolic requirements, including unusual sulphide and carbon dioxide assimilation and transport mechanisms. Symbiont genome sequencing has improved our knowledge of potential bacterial metabolism and should rapidly open the way for new research approaches to resolve the intricate physiological relationships between a eukaryotic host and its chemoautotrophic bacterial symbionts.
{"title":"The biology of vestimentiferan tubeworms","authors":"M. Bright, F. Lallier","doi":"10.1201/EBK1439821169-4","DOIUrl":"https://doi.org/10.1201/EBK1439821169-4","url":null,"abstract":"Vestimentiferan tubeworms, once erected at a phylum level, are now known to comprise a part of the specialised deep-sea polychaete family Siboglinidae. Their widespread and abundant occurrence at hydrothermal vents and hydrocarbon seeps has fostered numerous studies of their evolution and biogeography, ecology and physiology. Harbouring autotrophic, sulphide-oxidising, intracellular bacterial symbionts, they form large populations of `primary' producers with contrasting characteristics, from fast-growing, short-living species at vents, to slow-growing, long-living species at seeps. These different life strategies and the ways they modify the biogeochemistry of their respective environments have consequences on the macro- and meiofaunal assemblages that develop within vestimentiferan bushes. New findings indicate that postlarval recruits get infected through the skin by free-living bacteria for which growth is rapidly and specifically limited by the host to mesoderm cells around the gut that further transform into the characteristic trophosome. The resulting internal location of symbionts prompts specific adaptations of the hosts to fulfil their metabolic requirements, including unusual sulphide and carbon dioxide assimilation and transport mechanisms. Symbiont genome sequencing has improved our knowledge of potential bacterial metabolism and should rapidly open the way for new research approaches to resolve the intricate physiological relationships between a eukaryotic host and its chemoautotrophic bacterial symbionts.","PeriodicalId":54693,"journal":{"name":"Oceanography and Marine Biology","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2010-05-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89547869","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2010-01-01DOI: 10.1201/EBK1439821169-C3
G. Tsounis, S. Rossi, R. Grigg, G. Santangelo, L. Bramanti, J. Gili
Precious corals have been commercially exploited for many centuries all over the world. Their skeletons have been used as amulets or jewellery since antiquity and are one of the most valuable living marine resources. Precious coral fisheries are generally characterized by the 'boom-and-bust' principle, quickly depleting a discovered stock and then moving on to the next one. Most known stocks are overexploited today, and populations are in decline. The unsustainable nature of most fisheries is clearly revealed by analyzing all available data. Precious corals belong to the functional group of deep corals and are important structure-forming organisms, so called ecosystem engineers, that provide shelter for other organisms, increasing biodiversity. Yet, their management is usually focused on single species rather than a holistic habitat management approach. This review compares the biology of precious corals as well as the historical ecology and the socioeconomy of their fisheries to improve precious coral management and conservation. The analysis demonstrates that a paradigm shift is necessary in precious coral exploitation, not only to conserve habitats of high biodiversity but also to achieve sustainable fisheries and stabilize a specialized jewellery industry.
{"title":"The Exploitation and Conservation of Precious Corals","authors":"G. Tsounis, S. Rossi, R. Grigg, G. Santangelo, L. Bramanti, J. Gili","doi":"10.1201/EBK1439821169-C3","DOIUrl":"https://doi.org/10.1201/EBK1439821169-C3","url":null,"abstract":"Precious corals have been commercially exploited for many centuries all over the world. Their skeletons have been used as amulets or jewellery since antiquity and are one of the most valuable living marine resources. Precious coral fisheries are generally characterized by the 'boom-and-bust' principle, quickly depleting a discovered stock and then moving on to the next one. Most known stocks are overexploited today, and populations are in decline. The unsustainable nature of most fisheries is clearly revealed by analyzing all available data. Precious corals belong to the functional group of deep corals and are important structure-forming organisms, so called ecosystem engineers, that provide shelter for other organisms, increasing biodiversity. Yet, their management is usually focused on single species rather than a holistic habitat management approach. This review compares the biology of precious corals as well as the historical ecology and the socioeconomy of their fisheries to improve precious coral management and conservation. The analysis demonstrates that a paradigm shift is necessary in precious coral exploitation, not only to conserve habitats of high biodiversity but also to achieve sustainable fisheries and stabilize a specialized jewellery industry.","PeriodicalId":54693,"journal":{"name":"Oceanography and Marine Biology","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2010-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78625934","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2010-01-01DOI: 10.1201/ebk1439821169-c1
Yuri P. Springer, C. Hays, M. Carr, Megan R. Mackey
Ecosystem-based management is predicated on the multifaceted and interconnected nature of biological communities and of human impacts on them. Species targeted by humans for extraction can have multiple ecological functions and provide societies with a variety of services, and management practices must recognize, accommodate, and balance these diverse values. Similarly, multiple human activities can affect biological resources, and the separate and interactive effects of these activities must be understood to develop effective management plans. Species of large brown algae in the order Laminariales (kelps) are prominent members of shallow subtidal marine communities associated with temperate coastlines worldwide. They provide a diversity of ecosystem services, perhaps most notably the fuelling of primary production and detritus-based food webs and the creation of biogenic habitat that increases local species diversity and abundance. Species of kelp have also been collected for a variety of purposes throughout the history of human habitation of these coastlines. The bull kelp, Nereocystis luetkeana, provides a clear example of how the development of sustainable harvest policies depends critically on an understanding of the morphological, physiological, life-history, demographic, and ecological traits of a species. However, for Nereocystis as well as many other marine species, critical biological data are lacking. This review summarizes current knowledge of bull kelp biology, ecological functions and services, and past and ongoing management practices and concludes by recommending research directions for moving toward an ecosystem-based approach to managing this and similarly important kelps in shallow temperate rocky reef ecosystems.
{"title":"TOWARD ECOSYSTEM-BASED MANAGEMENT OF MARINE MACROALGAE—THE BULL KELP, NEREOCYSTIS LUETKEANA","authors":"Yuri P. Springer, C. Hays, M. Carr, Megan R. Mackey","doi":"10.1201/ebk1439821169-c1","DOIUrl":"https://doi.org/10.1201/ebk1439821169-c1","url":null,"abstract":"Ecosystem-based management is predicated on the multifaceted and interconnected nature of biological communities and of human impacts on them. Species targeted by humans for extraction can have multiple ecological functions and provide societies with a variety of services, and management practices must recognize, accommodate, and balance these diverse values. Similarly, multiple human activities can affect biological resources, and the separate and interactive effects of these activities must be understood to develop effective management plans. Species of large brown algae in the order Laminariales (kelps) are prominent members of shallow subtidal marine communities associated with temperate coastlines worldwide. They provide a diversity of ecosystem services, perhaps most notably the fuelling of primary production and detritus-based food webs and the creation of biogenic habitat that increases local species diversity and abundance. Species of kelp have also been collected for a variety of purposes throughout the history of human habitation of these coastlines. The bull kelp, Nereocystis luetkeana, provides a clear example of how the development of sustainable harvest policies depends critically on an understanding of the morphological, physiological, life-history, demographic, and ecological traits of a species. However, for Nereocystis as well as many other marine species, critical biological data are lacking. This review summarizes current knowledge of bull kelp biology, ecological functions and services, and past and ongoing management practices and concludes by recommending research directions for moving toward an ecosystem-based approach to managing this and similarly important kelps in shallow temperate rocky reef ecosystems.","PeriodicalId":54693,"journal":{"name":"Oceanography and Marine Biology","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2010-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88187548","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
R. Gibson, R. Atkinson, J. Gordon, J. Micael, M. J. Alves, A. Costa, M. Jones
The phylum Echinodermata contains some of the most charismatic benthic marine invertebrates and has become a symbol of marine life. However, growing global pressures on the collection of echinoderms for various commercial enterprises have put these enigmatic invertebrates under threat. This review summarises the demands on echinoderms from commercial fisheries, aquarium and souvenir trades, as part of the global search for bioactive compounds from marine organisms, and as experimental models in evolution and toxicology, and highlights the urgent need for an integrated global strategy for their protection and conservation. Sea urchins and sea cucumbers are fished commercially worldwide. Increased landings, limited information on population biology and lack of stringent management of the fisheries have resulted in a global decline of populations. In addition to being a target species for commercial fishing, many echinoderms form part of the significant by-catch produced from the general use of fishing hardware. Even when they are not caught directly, echinoderms may be damaged to varying degrees as the gear passes over them and may be affected indirectly by the physical disturbance caused by fishing gear to the seafloor. Echinoderms are gaining popularity with aquarists and account for about 17% of the global trade. Pharmaceutical companies are constantly screening marine organisms for biochemical compounds for potential use in medicine, traditional healing and industrial applications. The marine bioprospecting industry is not regulated and, although at an early stage of development, the huge potential of echinoderms to provide bioactive products highlights the need for urgent action to regulate this kind of activity. Echinoderm embryos and larvae have been used as experimental model systems in several lines of research for more than a century, leading to significant advances in the areas of developmental biology, cell biology and immunology. In addition, echinoderms are well known for their striking regenerative capacity and have provided a valuable experimental model to identify the genes involved in the process of neural regeneration. Sea urchin gametes, embryos and larvae have also been used for fast, low-cost and reliable screening of toxic substances, and for detailed studies of their mechanism of action. One way to mitigate the commercial exploitation of wild echinoderm stocks is to develop laboratory culture methods to produce individuals for reseeding exploited populations and this is being done with sea urchins and sea cucumbers. However, releasing large numbers of captive-bred animals into the wild will undoubtedly affect the genetic composition of local populations, giving rise to important ethical issues related to the loss of a genetically unique wild stock. To aid conservation, it is necessary to improve the collection of data to quantify the extent of harvesting echinoderms and to document the location and catch data by species. It
{"title":"EXPLOITATION AND CONSERVATION OF ECHINODERMS","authors":"R. Gibson, R. Atkinson, J. Gordon, J. Micael, M. J. Alves, A. Costa, M. Jones","doi":"10.1201/9781420094220-7","DOIUrl":"https://doi.org/10.1201/9781420094220-7","url":null,"abstract":"The phylum Echinodermata contains some of the most charismatic benthic marine invertebrates and has become a symbol of marine life. However, growing global pressures on the collection of echinoderms for various commercial enterprises have put these enigmatic invertebrates under threat. This review summarises the demands on echinoderms from commercial fisheries, aquarium and souvenir trades, as part of the global search for bioactive compounds from marine organisms, and as experimental models in evolution and toxicology, and highlights the urgent need for an integrated global strategy for their protection and conservation. Sea urchins and sea cucumbers are fished commercially worldwide. Increased landings, limited information on population biology and lack of stringent management of the fisheries have resulted in a global decline of populations. In addition to being a target species for commercial fishing, many echinoderms form part of the significant by-catch produced from the general use of fishing hardware. Even when they are not caught directly, echinoderms may be damaged to varying degrees as the gear passes over them and may be affected indirectly by the physical disturbance caused by fishing gear to the seafloor. Echinoderms are gaining popularity with aquarists and account for about 17% of the global trade. Pharmaceutical companies are constantly screening marine organisms for biochemical compounds for potential use in medicine, traditional healing and industrial applications. The marine bioprospecting industry is not regulated and, although at an early stage of development, the huge potential of echinoderms to provide bioactive products highlights the need for urgent action to regulate this kind of activity. Echinoderm embryos and larvae have been used as experimental model systems in several lines of research for more than a century, leading to significant advances in the areas of developmental biology, cell biology and immunology. In addition, echinoderms are well known for their striking regenerative capacity and have provided a valuable experimental model to identify the genes involved in the process of neural regeneration. Sea urchin gametes, embryos and larvae have also been used for fast, low-cost and reliable screening of toxic substances, and for detailed studies of their mechanism of action. One way to mitigate the commercial exploitation of wild echinoderm stocks is to develop laboratory culture methods to produce individuals for reseeding exploited populations and this is being done with sea urchins and sea cucumbers. However, releasing large numbers of captive-bred animals into the wild will undoubtedly affect the genetic composition of local populations, giving rise to important ethical issues related to the loss of a genetically unique wild stock. To aid conservation, it is necessary to improve the collection of data to quantify the extent of harvesting echinoderms and to document the location and catch data by species. It ","PeriodicalId":54693,"journal":{"name":"Oceanography and Marine Biology","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2009-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79612297","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2009-01-01DOI: 10.1201/9781420094220.CH3
L. Hastie, G. Pierce, Jianjun Wang, I. Bruno, A. Moreno, U. Piatkowski, J. Robin
Cephalopods play a significant role in coastal and oceanic ecosystems, both as consumers of invertebrates and small fish and as the prey of some fish, seabirds and marine mammals and other large predators. Approximately 30 species of cephalopod have been recorded in the north-eastern Atlantic and adjacent waters, including 18 teuthid (squid), seven sepiolid (bobtail), three sepiid (cuttlefish) and 10 octopod (octopus) species. A number of these are exploited commercially and support important target and by-catch fisheries in Western Europe. During the past decade, annual landings of cephalopods from the north-eastern Atlantic (International Council for the Exploration of the Sea [ICES] area) have ranged from 40,000 to 55,000 t, including substantial catches of long-fin (loliginid) squid (7000–11,000 t per annum), short-fin (ommastrephid) squid (3000–10,000 t), cuttlefish (including sepiolids; 16,000–24,000 t) and octopods (12,000–18,000 t). The most important exploited species in the north-eastern Atlantic are Eledone cirrhosa, Illex coindetii, Loligo forbesi, Loligo vulgaris, Octopus vulgaris, Todarodes sagittatus, Todaropsis eblanae and Sepia officinalis. Other species including Alloteuthis subulata, Gonatus fabricii and certain sepiolids, appear to be abundant and may be marketable. Cephalopods tend to rapidly concentrate heavy metals and other toxic substances in their tissues and this plays an important role in the bioaccumulation of these pollutants in marine predators as well as having implications for human consumption. High levels of cadmium and mercury are often recorded in cephalopod tissues. Another important environmental issue concerns the potential impact of widespread human activity on cephalopod spawning areas, particularly bottom-fishing operations but also shipping, and oil exploration and production. In contrast to many finfish species that spawn annually over a number of years, most cephalopods live only 1–2 yr and die after spawning. Therefore, failure to reproduce and recruit adequately in any given year may seriously impact the long-term viability of cephalopod stocks. Climate change is expected to have a significant effect on many species in the north-eastern Atlantic. This review provides a detailed account of the zoogeography, biology and ecology of cephalopods in the north-eastern Atlantic, on a species-by-species basis. Important economic, ecological and conservation issues affecting cephalopods in this area are also discussed
{"title":"Cephalopods in the north-eastern Atlantic: Species, biogeography, ecology, exploitation and conservation","authors":"L. Hastie, G. Pierce, Jianjun Wang, I. Bruno, A. Moreno, U. Piatkowski, J. Robin","doi":"10.1201/9781420094220.CH3","DOIUrl":"https://doi.org/10.1201/9781420094220.CH3","url":null,"abstract":"Cephalopods play a significant role in coastal and oceanic ecosystems, both as consumers of invertebrates and small fish and as the prey of some fish, seabirds and marine mammals and other large predators. Approximately 30 species of cephalopod have been recorded in the north-eastern Atlantic and adjacent waters, including 18 teuthid (squid), seven sepiolid (bobtail), three sepiid (cuttlefish) and 10 octopod (octopus) species. A number of these are exploited commercially and support important target and by-catch fisheries in Western Europe. During the past decade, annual landings of cephalopods from the north-eastern Atlantic (International Council for the Exploration of the Sea [ICES] area) have ranged from 40,000 to 55,000 t, including substantial catches of long-fin (loliginid) squid (7000–11,000 t per annum), short-fin (ommastrephid) squid (3000–10,000 t), cuttlefish (including sepiolids; 16,000–24,000 t) and octopods (12,000–18,000 t). The most important exploited species in the north-eastern Atlantic are Eledone cirrhosa, Illex coindetii, Loligo forbesi, Loligo vulgaris, Octopus vulgaris, Todarodes sagittatus, Todaropsis eblanae and Sepia officinalis. Other species including Alloteuthis subulata, Gonatus fabricii and certain sepiolids, appear to be abundant and may be marketable. Cephalopods tend to rapidly concentrate heavy metals and other toxic substances in their tissues and this plays an important role in the bioaccumulation of these pollutants in marine predators as well as having implications for human consumption. High levels of cadmium and mercury are often recorded in cephalopod tissues. Another important environmental issue concerns the potential impact of widespread human activity on cephalopod spawning areas, particularly bottom-fishing operations but also shipping, and oil exploration and production. In contrast to many finfish species that spawn annually over a number of years, most cephalopods live only 1–2 yr and die after spawning. Therefore, failure to reproduce and recruit adequately in any given year may seriously impact the long-term viability of cephalopod stocks. Climate change is expected to have a significant effect on many species in the north-eastern Atlantic. This review provides a detailed account of the zoogeography, biology and ecology of cephalopods in the north-eastern Atlantic, on a species-by-species basis. Important economic, ecological and conservation issues affecting cephalopods in this area are also discussed","PeriodicalId":54693,"journal":{"name":"Oceanography and Marine Biology","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2009-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"72817939","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Diel vertical migration (DVM) is a characteristic behavioural pattern performed by zooplankton in which their vertical distribution changes over the 24-h day. Here the proximate control of zooplankton DVM is reviewed. Light has emerged as the major proximate cue controlling DVM behaviour and the understanding of zooplankton visual physiology and the light-mediated behaviour underlying DVM is expanding. Field and laboratory evidence exist to support each of the three major hypotheses for the exogenous role of light in DVM: (1) preferendum or isolume, (2) absolute intensity threshold, and (3) relative rate of change. Light may also play an endogenous role in DVM by entraining circadian rhythms in vertical movement or activity. This appreciation of the role of light has improved modelling efforts into the causes and consequences of DVM. The most important recent advance in the study of DVM is the recognition that this behaviour is a phenotypic response in many species and is most commonly activated by chemical cues (kairomones) from fish predators. High levels of kairomones signal high levels of predation pressure, and DVM-related photobehaviours, such as swimming responses on relative rates of irradiance change, are altered such that migration occurs and zooplankton achieve a refuge from visual predators.
Diel vertical migration (DVM)是浮游动物在24小时内垂直分布变化的一种特有的行为模式。本文就浮游动物DVM的近因控制作一综述。光已经成为控制DVM行为的主要直接线索，并且对浮游动物视觉生理和光介导的DVM行为的理解正在扩大。现有的现场和实验室证据支持光在DVM中外源作用的三个主要假设:(1)首选或等量，(2)绝对强度阈值，(3)相对变化率。光也可能通过在垂直运动或活动中引入昼夜节律而在DVM中发挥内源性作用。这种对光的作用的认识已经改进了对DVM的原因和后果的建模工作。DVM研究中最重要的最新进展是认识到这种行为是许多物种的一种表型反应，最常见的是由来自鱼类捕食者的化学线索(kairomones)激活。高水平的kairomones表示高水平的捕食压力，并且与dvm相关的光行为，例如对相对辐照率变化的游泳反应，被改变，从而发生迁移，浮游动物获得了躲避视觉捕食者的避难所。
{"title":"ZOOPLANKTON DIEL VERTICAL MIGRATION — A REVIEW OF PROXIMATE CONTROL","authors":"Jonathan H. Cohen, R. Forward","doi":"10.1201/9781420094220-5","DOIUrl":"https://doi.org/10.1201/9781420094220-5","url":null,"abstract":"Diel vertical migration (DVM) is a characteristic behavioural pattern performed by zooplankton in which their vertical distribution changes over the 24-h day. Here the proximate control of zooplankton DVM is reviewed. Light has emerged as the major proximate cue controlling DVM behaviour and the understanding of zooplankton visual physiology and the light-mediated behaviour underlying DVM is expanding. Field and laboratory evidence exist to support each of the three major hypotheses for the exogenous role of light in DVM: (1) preferendum or isolume, (2) absolute intensity threshold, and (3) relative rate of change. Light may also play an endogenous role in DVM by entraining circadian rhythms in vertical movement or activity. This appreciation of the role of light has improved modelling efforts into the causes and consequences of DVM. The most important recent advance in the study of DVM is the recognition that this behaviour is a phenotypic response in many species and is most commonly activated by chemical cues (kairomones) from fish predators. High levels of kairomones signal high levels of predation pressure, and DVM-related photobehaviours, such as swimming responses on relative rates of irradiance change, are altered such that migration occurs and zooplankton achieve a refuge from visual predators.","PeriodicalId":54693,"journal":{"name":"Oceanography and Marine Biology","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2009-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73634012","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Over the last 40 years, underwater stereo-image measurement systems have employed stereo-cameras and paired single cameras in a variety of configurations. Both still and movie cameras have been used, based on film, video tube and digital sensors. Whilst measurement configurations of all varieties have been used, the transect has been, and still is, the predominant sampling technique. These basic approaches to photogrammetric geometry and sampling techniques are still in use today; however, the image quality has advanced considerably and the use of fully digital video systems and digital still cameras is now commonplace. The wider use of precalibrated, self-contained stereo-image systems, plus the substantial improvements in image resolution and image fidelity, is enabling new possibilities for accurate and reliable measurement of 3-dimensional lengths, surfaces and volumes. These advances are leading to significant improvements in the effectiveness of the management of marine ecosystems for conservation and the estimation of biomass for aquaculture. This work reviews the status of underwater stereo-image measurement and illustrates applications of stereo-image measurement in marine biology and ecology.
{"title":"A Review of Underwater Stereo-Image Measurement for Marine Biology and Ecology Applications","authors":"M. Shortis, E. Harvey, D. Abdo","doi":"10.1201/9781420094220-9","DOIUrl":"https://doi.org/10.1201/9781420094220-9","url":null,"abstract":"Over the last 40 years, underwater stereo-image measurement systems have employed stereo-cameras and paired single cameras in a variety of configurations. Both still and movie cameras have been used, based on film, video tube and digital sensors. Whilst measurement configurations of all varieties have been used, the transect has been, and still is, the predominant sampling technique. These basic approaches to photogrammetric geometry and sampling techniques are still in use today; however, the image quality has advanced considerably and the use of fully digital video systems and digital still cameras is now commonplace. The wider use of precalibrated, self-contained stereo-image systems, plus the substantial improvements in image resolution and image fidelity, is enabling new possibilities for accurate and reliable measurement of 3-dimensional lengths, surfaces and volumes. These advances are leading to significant improvements in the effectiveness of the management of marine ecosystems for conservation and the estimation of biomass for aquaculture. This work reviews the status of underwater stereo-image measurement and illustrates applications of stereo-image measurement in marine biology and ecology.","PeriodicalId":54693,"journal":{"name":"Oceanography and Marine Biology","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2009-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82511814","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Sardine (Sardina pilchardus, Walbaum, 1792) and anchovy (Engraulis encrasicolus, Linnaeus, 1758) are two commercially important coastal pelagic species. The important ecological role of these two species in Mediterranean ecosystems has been recently highlighted and in the Adriatic in particular, anchovy and sardine have been found to play an essential role through the capture of energy from the lower trophic levels, making it available to the higher trophic levels. Furthermore, they are of major importance for Adriatic fisheries, accounting, together, for approximately 41% of total Adriatic marine catches and constituting extremely important shared fisheries resources. The ecological and fisheries importance of these two species, which essentially coexist in a relatively small area, prompted the authors to carry out a critical review of the information regarding their ecology. For each species information available on reproduction and migrations, feeding and predation, schooling and behaviour, growth and mortality, and genetic variability was collected and critically evaluated in an ecosystem functioning and fisheries context. The aim of the review is to try to understand the ecological differences and similarities allowing the coexistence of the two species as well as to identify the extent and geographic distribution of information as an aid to future research efforts.
{"title":"ANCHOVY AND SARDINE IN THE ADRIATIC SEA — AN ECOLOGICAL REVIEW","authors":"E. Morello, E. Arneri","doi":"10.1201/9781420094220-8","DOIUrl":"https://doi.org/10.1201/9781420094220-8","url":null,"abstract":"Sardine (Sardina pilchardus, Walbaum, 1792) and anchovy (Engraulis encrasicolus, Linnaeus, 1758) are two commercially important coastal pelagic species. The important ecological role of these two species in Mediterranean ecosystems has been recently highlighted and in the Adriatic in particular, anchovy and sardine have been found to play an essential role through the capture of energy from the lower trophic levels, making it available to the higher trophic levels. Furthermore, they are of major importance for Adriatic fisheries, accounting, together, for approximately 41% of total Adriatic marine catches and constituting extremely important shared fisheries resources. The ecological and fisheries importance of these two species, which essentially coexist in a relatively small area, prompted the authors to carry out a critical review of the information regarding their ecology. For each species information available on reproduction and migrations, feeding and predation, schooling and behaviour, growth and mortality, and genetic variability was collected and critically evaluated in an ecosystem functioning and fisheries context. The aim of the review is to try to understand the ecological differences and similarities allowing the coexistence of the two species as well as to identify the extent and geographic distribution of information as an aid to future research efforts.","PeriodicalId":54693,"journal":{"name":"Oceanography and Marine Biology","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2009-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83603993","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2008-06-05DOI: 10.1201/9781420065756.CH4
R. Villanueva, M. Norman
Octopuses of the family Octopodidae adopt two major life-history strategies. The first is the production of relatively few, large eggs resulting in well-developed hatchlings that resemble the adults and rapidly adopt the benthic habit of their parents. The second strategy is production of numerous small eggs that hatch into planktonic, free-swimming hatchlings with few suckers, simple chromatophores and transparent musculature. These distinctive planktonic stages are termed para-larvae and differ from conspecific adults in their morphology, physiology, ecology and behaviour. This study aims to review available knowledge on this subject. In benthic octopuses with plank. tonic stages, spawning characteristics and duration of planktonic life seem to play an important role in their dispersal capacities. Duration of the hatching period of a single egg mass can range from 2 days to 11 wk, while duration of the planktonic stage can range from 3 wk to half a year, depending on the species and temperature. Thus these paralarvae possess considerable potential for dispersal. In some species, individuals reach relatively large sizes while living as part of the micronekton of oceanic, epipelagic waters. Such forms appear to delay settlement for an unknown period that is suspected to be longer than for paralarvae in more coastal, neritic waters. During the planktonic period, paralarval octopuses feed on crustaceans as their primary prey. In addition to the protein, critical to the protein-based metabolism of octopuses (and all cephalopods), the lipid and copper contents of the prey also appear important in maintaining normal growth. Littoral and oceanic fishes are their main predators and defence behaviours may involve fast swimming speeds, use of ink decoys, dive responses and camouflage. Sensory systems of planktonic stages include photo-, mechano- and chemoreceptors controlled by a highly evolved nervous system that follows the general pattern described for adult cephalopods. On settlement, a major metamorphosis occurs in morphology, physiology and behaviour. Morphological changes associated with the settlement process include positive allometric arm growth; chromatophore, iridophore and leucophore genesis; development of skin sculptural components and a horizontal pupillary response. At the same time, animals lose the Kolliker organs that cover the body surface, the 'lateral line system' and the oral denticles of the beaks. Strong positive phototaxis is a common response for hatchlings and some later paralarval stages but this response reduces, disappears or reverses after settlement. There are many gaps in our knowledge of the planktonic phases of benthic octopuses. Most of our understanding of octopus paralarvae comes from studies of just two species (Octopus vulgaris and Enteroctopus dofleini) and knowledge of the vast majority of benthic octopus species with planktonic stages is considered rudimentary or non-existent. Research is needed in a variety of
{"title":"Biology of the planktonic stages of benthic octopuses","authors":"R. Villanueva, M. Norman","doi":"10.1201/9781420065756.CH4","DOIUrl":"https://doi.org/10.1201/9781420065756.CH4","url":null,"abstract":"Octopuses of the family Octopodidae adopt two major life-history strategies. The first is the production of relatively few, large eggs resulting in well-developed hatchlings that resemble the adults and rapidly adopt the benthic habit of their parents. The second strategy is production of numerous small eggs that hatch into planktonic, free-swimming hatchlings with few suckers, simple chromatophores and transparent musculature. These distinctive planktonic stages are termed para-larvae and differ from conspecific adults in their morphology, physiology, ecology and behaviour. This study aims to review available knowledge on this subject. In benthic octopuses with plank. tonic stages, spawning characteristics and duration of planktonic life seem to play an important role in their dispersal capacities. Duration of the hatching period of a single egg mass can range from 2 days to 11 wk, while duration of the planktonic stage can range from 3 wk to half a year, depending on the species and temperature. Thus these paralarvae possess considerable potential for dispersal. In some species, individuals reach relatively large sizes while living as part of the micronekton of oceanic, epipelagic waters. Such forms appear to delay settlement for an unknown period that is suspected to be longer than for paralarvae in more coastal, neritic waters. During the planktonic period, paralarval octopuses feed on crustaceans as their primary prey. In addition to the protein, critical to the protein-based metabolism of octopuses (and all cephalopods), the lipid and copper contents of the prey also appear important in maintaining normal growth. Littoral and oceanic fishes are their main predators and defence behaviours may involve fast swimming speeds, use of ink decoys, dive responses and camouflage. Sensory systems of planktonic stages include photo-, mechano- and chemoreceptors controlled by a highly evolved nervous system that follows the general pattern described for adult cephalopods. On settlement, a major metamorphosis occurs in morphology, physiology and behaviour. Morphological changes associated with the settlement process include positive allometric arm growth; chromatophore, iridophore and leucophore genesis; development of skin sculptural components and a horizontal pupillary response. At the same time, animals lose the Kolliker organs that cover the body surface, the 'lateral line system' and the oral denticles of the beaks. Strong positive phototaxis is a common response for hatchlings and some later paralarval stages but this response reduces, disappears or reverses after settlement. There are many gaps in our knowledge of the planktonic phases of benthic octopuses. Most of our understanding of octopus paralarvae comes from studies of just two species (Octopus vulgaris and Enteroctopus dofleini) and knowledge of the vast majority of benthic octopus species with planktonic stages is considered rudimentary or non-existent. Research is needed in a variety of","PeriodicalId":54693,"journal":{"name":"Oceanography and Marine Biology","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2008-06-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81487707","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2008-06-05DOI: 10.1201/9781420065756-10
W. C. Leggett, K. Frank
The development of the field of fisheries oceanography over the past century has been heavily influenced by a relatively small number of paradigms that have shaped thinking, influenced lines of enquiry and occasionally stalled progress in the field. This review provides an overview of what are considered to be the most influential paradigms in the discipline. Each begins with a brief discussion of its origins. Next their respective (and often overlapping) impact on the development of the discipline is discussed and then the evolution of these paradigms as shaped by new advances in approaches and technologies and by direct challenges to their underlying assumptions is reviewed. For each, the endpoint is an overview of the current state of knowledge and thinking and the probable future direction of research in the area. The review concludes with an overview of the probable future directions of research in the discipline as a whole.
{"title":"Paradigms in fisheries oceanography","authors":"W. C. Leggett, K. Frank","doi":"10.1201/9781420065756-10","DOIUrl":"https://doi.org/10.1201/9781420065756-10","url":null,"abstract":"The development of the field of fisheries oceanography over the past century has been heavily influenced by a relatively small number of paradigms that have shaped thinking, influenced lines of enquiry and occasionally stalled progress in the field. This review provides an overview of what are considered to be the most influential paradigms in the discipline. Each begins with a brief discussion of its origins. Next their respective (and often overlapping) impact on the development of the discipline is discussed and then the evolution of these paradigms as shaped by new advances in approaches and technologies and by direct challenges to their underlying assumptions is reviewed. For each, the endpoint is an overview of the current state of knowledge and thinking and the probable future direction of research in the area. The review concludes with an overview of the probable future directions of research in the discipline as a whole.","PeriodicalId":54693,"journal":{"name":"Oceanography and Marine Biology","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2008-06-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80054766","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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