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1.
Cyanide-free Net-caught Fish for the Marine Aquarium Trade   总被引:1,自引:0,他引:1  
The International Marinelife Alliance (IMA) has been training collectors in the Philippines and Indonesia to use barrier-nets rather than sodium cyanide to capture marine-aquarium fish. Despite the training, collectors have been slow to switch to using nets because they can earn more using cyanide. A new Philippine export company has agreed to pay the collectors more for net-caught fish and to adhere to standards being set by the USA-based Marine Aquarium Council. The IMA is monitoring the collectors and conducting cyanide testing to certify that the fish are net-caught and totally cyanide-free. Clearance certificates now accompany shipments of these marine-aquarium fish being shipped to wholesalers and retailers associated with the American Marine Dealers Association (AMDA) situated in the USA and Canada. AMDA members are being surveyed to assess whether the net-caught fish are more cost competitive compared to cyanide-caught fish for the marine ornamental fish trade because of reduced mortality through the chain from reef to retailer.  相似文献   

2.
Reef fish, corals, and other marine invertebrate species associated with coral reefs need to be managed in a sustainable manner to halt destructive fishing in the Philippines and other Southeast Asian countries. As part of the Coastal Communities Empowerment Project, the International Marinelife Alliance (IMA) plans to implement Territorial Use Rights in Fisheries (TURFs) to help manage municipal waters; while creating alternative livelihoods for small-scale fishermen and their families. Changes to the Local Government Code allow Philippine municipal councils to regulate fishing and mariculture in waters within 15km from shore. The councils can lease TURFs to local fisherfolk and prevent their use by those outside the community. The IMA plans to help create several types of TURFs. These include TURFs used by aquarium-fish collectors, for rearing giant clams, and for farming live rock and coral fragments. The TURFs are part of a larger strategy to conserve marine biodiversity, protect and restore marine habitats, and promote sustainable use of marine resources by local people. Fish and invertebrates harvested from the TURFs will be used in programs to restore marine habitats and to generate income from exports that supply the aquarium trade.  相似文献   

3.
  • 1. A detailed study on the spatial and temporal patterns of reef fish assemblages associated with non‐reefal coral communities at A Ma Wan (AMW) and A Ye Wan (AYW) in Tung Ping Chau, Hong Kong, China, was carried out using an underwater visual census method from January 1998 to December 1999.
  • 2. The study identified a total of 106 species (76 genera in 39 families) of fish in the study sites, in which 88 species were recorded in AMW and 78 species in AYW. Seasonal patterns in the abundance and species richness of all reef fishes and most of the frequently encountered families/trophic groups in both study sites were observed. Seasonal fluctuation of macroalgae, the influence of recruitment of larvae, and the possible seasonal variation in the behaviour of fish may all contribute to these observed seasonal patterns.
  • 3. Multidimensional scaling (MDS) ordinations demonstrated that there were spatial variations in the fish community structures within and between sites. Such spatial patterns were possibly related to the spatial variation of the coral community structures in the study sites. The ordinations also showed that the fish community structures in the study sites were not seasonally stable. Such temporal instability of the fish community structures may be partly due to habitat isolation among the fish communities around the island.
  • 4. These results imply that preservation and enhancement of habitat connectivity of the coral communities should be one of the main conservation strategies for the reef fish communities of Tung Ping Chau, and those of Hong Kong in general. This strategy may be equally applicable to other non‐reefal coral communities elsewhere around the world.
Copyright © 2008 John Wiley & Sons, Ltd.  相似文献   

4.
Abstract

This paper provides a case study of the evolution of the freshwater food fish and marine food fish culture industries in Hong Kong as a highly urbanized and polluted metropolis. This study lends support to the thesis that marine fish culture is generally more sustainable than pond fish culture, owing to the fact that oceanic resources are relatively less scarce than land resources ‐ even though the transaction costs of delineating and enforcing private property in the former are much higher. The case study gives a brief historical account of the evolution of the freshwater food fish and marine food fish culture industries in Hong Kong, identifies the technical inputs constraining the survival and prospects of these industries, and evaluates the relevance of the private property rights approach to their sustainability. Examination of the culture industries reveals the differences in property right characteristics of both industries. In addition to the differentiation in the degree of privatization between freshwater food fish and marine food fish culture, the major characteristics and inputs for culture practices in both industries are also examined. A qualitative evaluation of the relative significance of these inputs to the sustainability of the culture industries is provided. It is argued that the escalation in the factor price of land will destroy the local pond fish culture industry even though it is more ‘private’ than marine fish culture, notwithstanding the fact that substantial areas of intertidal ponds are owned by government and that in‐filling of fishponds have been subject to stringent planning control. The policy implications of the case study are spelled out.  相似文献   

5.
The worldwide market for ornamental saltwater invertebrates supplies the needs of millions of aquarium hobbyists, as well as for public exhibition (zoos, aquaria), universities, and research institutions. The large-scale continuous collection of marine organisms is responsible, in many places, for the destruction of habitats, including coral reefs. The perceived expansion of the animal trade further threatens these fragile habitats. In the present paper, several concepts for the domestication of marine ornamental invertebrates (mainly colonial species) are discussed, offering an alternative commercial approach. The major rationale is based on future ex situ propagation, not field collections; a strategy aimed to circumvent the need for wild-harvested animals. This strategy is based on: (1) collection, settlement and metamorphosis of large numbers of larvae from marine organisms or of naturally shed germ cells under aquarium conditions, where survivorship exceeds several orders of magnitude than that in nature; (2) fragmentation of very small pieces (such as the size of a single polyp in colonial corals or blood vessel ampullae in tunicates) for the production of new colonies; (3) the development of replicates and inbred-lines from chosen ornamental species; (4) the use of cryopreservation of larvae and germ cells which will support the supply of material year-round; (5) several concepts for husbandry methods. Some benefits and deficiencies associated with the strategy for ex situ cultures are discussed, revealing its importance to the future of the trade.  相似文献   

6.
  • 1. This paper reports on the dynamics of the coral community structure at A Ma Wan (AMW) and A Ye Wan (AYW) in Tung Ping Chau, Hong Kong, focusing on data collected before and after the summer typhoon seasons in 1997 to 1999. This period (1999) experienced the highest frequency of severe tropical cyclones to hit Hong Kong with one cyclone being the strongest to hit in the last 23 years (1984 to 2006).
  • 2. This is part of a long‐term monitoring programme of subtropical coral communities that has been set up in AMW since May 1997 and AYW since May 1998 with nine fixed position 40 m long transects and 0.5 m × 0.5 m permanent quadrats laid at 5 m intervals along each transect. A total of 45 scleractinian coral species from 21 genera (12 families) was recorded, with 40 species in AMW and 32 species in AYW recorded at the beginning of the study.
  • 3. Multidimensional scaling ordinations showed distinct spatial variations in the coral communities within and between sites. These variations were probably a result of the differential effects of the repeated cyclone impacts on the communities. Cyphastrea serailia, Goniopora lobata, Montipora peltiformis and Pavona decussata were the dominant species most strongly affected by cyclone impacts at AMW, experiencing a 6.2–16.2% loss of mean area cover during the study period. Some dominant species (e.g. P. decussata) in AYW also experienced a 6.5–14.3% loss of mean area cover within the same period.
  • 4. Overall, these coral community structures appeared relatively stable and resistant to repeated physical disturbances. However, they may have low resilience towards more severe disturbances in the future. Preserving the resilience of coral communities/species in Tung Ping Chau should be one of the main goals of coral conservation strategies for the island.
Copyright © 2008 John Wiley & Sons, Ltd.  相似文献   

7.
徐闻珊瑚礁保护区鱼类种类组成初步研究   总被引:3,自引:0,他引:3  
对徐闻珊瑚礁保护区栖息的鱼类进行4个季节的调查分析.结果表明,徐闻珊瑚礁保护区有鱼类2纲13目55科91属135种,其中软骨鱼纲有1目3科3属6种,硬骨鱼纲有12目52科88属129种.在硬骨鱼纲中鲈形目种类最多,有26科45属73种,约占总渔获物种类数的54.1%.在渔获的鱼类中底层鱼类有69种,中下层鱼类有34种,中上层鱼类有32种,分别占鱼类总种数的51.1%、25.2%和23.7%.在春季渔获的鱼类种数最多,有74种,夏季、秋季和冬季渔获鱼类种数变化较小,分别有38种、46种和52种,而在4个季节均有出现的鱼类仅有8种.  相似文献   

8.
The marine life fishing industry in Florida is defined by the state as the non-lethal harvest of marine plants, finfish, and invertebrates that are sold live for commercial purposes (primarily into the saltwater aquarium industry). Approximately 330 different species of finfish and invertebrates are harvested by marine life collectors in Florida, including 180 species of finfish and 150 species of invertebrates and plants. In 1998, the total dockside value of these species was approximately US$1.9 million. The industry is highly regulated via limits on gear, handling methods, harvest sizes, and trip/bag/possession limits. Entry into the industry has been recently curtailed by the implementation of a moratorium on marine life endorsements. The total number of licensed harvesters exceeded 700 in 1998. Approximately 70 wholesales buyers also participated in the market during 1998. The majority of the dockside value is generated in south Florida, with the majority of the remaining value accruing from the region including and north of Tampa Bay. Over 80% of the total value associated with both finfish and invertebrates is generated by only 10 species within each group. Dockside prices vary considerably among the various species landed, with those landed in greater volumes exhibiting the lower prices.  相似文献   

9.
First feeding performance of the milletseed butterflyfish (Chaetodon miliaris) was evaluated using three experiments examining prey type, microalgal cell density and prey density. To ensure no size bias existed between trials, morphometric measurements, fertilization and hatch rates were recorded for each trial. The proportion of larvae feeding and feeding intensity were measured in each experiment. To evaluate prey type, larvae were offered small size Brachionus plicatilis and Parvocalanus crassirostris nauplii in clear water and water greened with Tisochrysis lutea (Tiso). In trial 1, green water and P. crassirostris nauplii had a significantly higher proportion of larvae feeding and feeding intensity. In trial 2 no differences were detected between P. crassirostris treatments. Microalgae experiments evaluated six treatments ranging from 0 cells/ml to 8 × 105 cells/ml. Feeding response increased as microalgae was added to the environment, but no statistical differences were discerned between treatments besides the highest cell density (8 × 105 cells/ml) and lowest cell density in both trials (0 cells/ml). To determine if prey density had an effect on first feeding response P. crassirostris nauplii were added to tanks at 1 to 15 nauplii/ml. No significant differences in the feeding response were found between prey densities of 1–15 P. crassirostris nauplii/ml in either trial. This study revealed that C. miliaris larvae had the highest first feeding response, measured by the proportion of larvae feeding and feeding intensity per larvae, with the prey item P. crassirostris nauplii in green water and prey densities between 1 and 15 nauplii/ml.  相似文献   

10.
This study was conducted to determine the effects of broodstock diet on flame angelfish (Centropyge loriculus) reproduction and generate baseline spawning performance (mean fecundity, egg fertilization, egg viability) and egg biochemistry data for this species. Sixteen flame angelfish broodstock pairs were maintained on one of three formulated diets or a raw diet (consisting of squid, shrimp, fish eggs and algae) to determine the effect of diet composition on the fecundity, egg fertilization rates and egg viability over a 7‐month period. Although all the diets supported similar mean spawn frequency and fecundity over the duration of the experiment, the mean fertilization rates and egg viability were significantly greater among pairs receiving the raw diet. Egg fatty acid composition was generally reflective of the maternal diet and similar to the values reported for other tropical species. In particular, dietary factors such as n‐3 highly unsaturated fatty acid and ARA level (which were elevated in the raw diet and eggs from fish receiving that treatment) are correlated with egg quality and are therefore worthy of future investigation. Because of the ease of conditioning, adaptability to varied formulated diets and continuous, sustained reproductive output, flame angelfish are an excellent model for examining the factors affecting marine fish egg and larval quality.  相似文献   

11.
西沙群岛重要珊瑚礁海域鱼类区系   总被引:6,自引:0,他引:6  
根据1998年5月、1999年5月和2003年5月在西沙群岛北礁、永兴岛、琛航岛、华光礁、浪花礁、金银岛、东岛和玉琢礁等8个岛礁的调查资料,研究了西沙群岛岛礁水域的鱼类区系。在8个岛礁共捕获鱼类48科261种,其中礁栖性鱼类占78.93%,在8个岛礁广泛分布的鱼类只有33种,各礁区之间种类的相似度不超过41%,因此,种类多样性高和相似度低是该区域鱼类区系的2个主要特征。与南沙岛礁(1998~1999)延绳钓、刺网和手钓以及南沙群岛西南陆架区(1991)、南海北部海域等底拖网鱼类相比较,物种相似度分别为34.0%、5.1%和6.8%。  相似文献   

12.
13.
Following independence from Ethiopia in 1993, Eritrea resumed exploiting Red Sea and Arabian fish species for the ornamental trade in 1995 as a means to earn foreign exchange from sparsely exploited marine resources. This paper describes the findings of research conducted in 1997, in collaboration with the Eritrean Ministry of Fisheries. The capture, transport and export of aquarium fish were reviewed and potential impacts and the status of management were investigated through liaison with stakeholders and researchers. From 1995 to 1997 two companies exported approximately 60,000 fish per year, mainly to the USA, worth US$65,000 (export value). Seventy-five species (from 22 families) were exported. Damselfishes made up two-thirds of total exports but more valuable families (angelfishes and butterflyfishes) were more economically significant. To earn revenue for Eritrea, a 20% export tax was imposed, although this was calculated from declarations by the operators. The emerging nature of the trade allowed detailed monitoring by the Ministry of Fisheries. However, management efforts were constrained by a lack of capacity for enforcement and baseline research. Several potential effects of the trade exist but other, land-based impacts may be more pressing concerns for Eritrea's reefs. Research priorities for management are discussed as well as the implications of mariculture of Eritrean species by other nations.  相似文献   

14.
西沙群岛珊瑚礁海域鱼类分类学多样性   总被引:10,自引:1,他引:10  
为评价南中国海西沙群岛珊瑚礁海域鱼类分类学多样性和更好地保护其鱼类,根据西沙群岛珊瑚礁海域鱼类物种组成的历史资料对西沙群岛及其16座岛礁的珊瑚礁水域鱼类物种数目、平均分类差异指数和16座岛礁的G-F多样性指数作了分析。结果显示,西沙共记录鱼类661种,隶属于25目、93科、305属。其中,永兴岛(351种),华光礁(173种),东岛(160种)记录鱼类物种数目较多。西沙鱼类平均分类差异指数(Δ+)约为60.2,各岛礁的Δ+与物种数目无关。中建岛、晋卿岛、玉琢礁等岛礁鱼类平均Δ+显著低于西沙鱼类Δ+。西沙鱼类Δ+小于陆架和河口区鱼类Δ+,说明珊瑚礁海域鱼类亲缘关系比陆架和河口区域的都要接近,此外大尺度上,一般纬度越低,中国海洋鱼类Δ+越小。但G-F多样性测度各指数由物种数目的大小决定,一般物种数目较大的岛礁G-F多样性各指数也相对较高,而RG-F指数更适合该海域鱼类多样性的测度。以石岛为例初步探讨了G-F指数为负的原因,一是物种数目较少,二是多样性测度的关键函数Y=-XLnX并不是单调函数所致;物种数目较大的岛礁如永兴岛、华光礁、东岛等应该成为西沙珊瑚礁海域鱼类保护的重点区域。  相似文献   

15.
Reef fishes are significant socially, nutritionally and economically, yet biologically they are vulnerable to both over‐exploitation and degradation of their habitat. Their importance in the tropics for living conditions, human health, food security and economic development is enormous, with millions of people and hundreds of thousands of communities directly dependent, and many more indirectly so. Reef fish fisheries are also critical safety valves in times of economic or social hardship or disturbance, and are more efficient, less wasteful and support far more livelihoods per tonne produced than industrial scale fisheries. Yet, relative to other fisheries globally, those associated with coral reefs are under‐managed, under‐funded, under‐monitored, and as a consequence, poorly understood or little regarded by national governments. Even among non‐governmental organizations, which are increasingly active in tropical marine issues, there is typically little focus on reef‐associated resources, the interest being more on biodiversity per se or protection of coral reef habitat. This essay explores the background and history to this situation, examines fishery trends over the last 30 years, and charts a possible way forward given the current realities of funding, capacity, development patterns and scientific understanding of coral reef ecosystems. The luxury live reef food‐fish trade is used throughout as a case study because it exemplifies many of the problems and challenges of attaining sustainable use of coral reef‐associated resources. The thesis developed is that sustaining reef fish fisheries and conserving biodiversity can be complementary, rather than contradictory, in terms of yield from reef systems. I identify changes in perspectives needed to move forward, suggest that we must be cautious of ‘fashionable’ solutions or apparent ‘quick fixes’, and argue that fundamental decisions must be made concerning the short and long‐term values of coral reef‐associated resources, particularly fish, for food and cash and regarding alternative sources of protein. Not to address the problems will inevitably lead to growing poverty, hardship and social unrest in many areas.  相似文献   

16.
Following the construction of a large-scale public aquarium, we were presented with an opportunity to investigate how wild caught Caribbean reef fish respond to their first encounter with a novel environment. Within the constraints of this opportunity, we designed a behavioural study to determine the reef fishes' response to a new habitat in relation to their locomotory mode. Nine species of fish representing three locomotory modes: carangiform, sub-carangiform and labriform/sub-carangiform were observed over a four-week period following their first introduction to the aquarium. Fish activity levels and spatial distribution were quantified in relation to time since their first encounter with the novel environment. The most important result was that, regardless of locomotory mode or ecology, all of the species extensively explored the novel environment rather than settle on the first habitat that they encountered. This is a particularly interesting result for territorial species. More specifically, however, there were significant differences between species in activity through time. Carangiform activity level was lowest in the initial phases of an encounter with the novel environment subsequently rising to a stable level. The other species had variable activity throughout the study, but all of them exhibited a phase of low activity at some stage during the study. In terms of the fishes' use of the 2.5 million litres of water, six species utilised the whole of the aquarium based on a predefined zoning scheme. Although the initial activity level was low, carangiform swimmers used at least 90% of the zones in the early phases of an encounter with the novel environment and subsequently used all of the zones. Sub-carangiform species also used 100% of the zones by the end of the study. Three of the four labriform/sub-carangiform swimmers used a maximum of 90% of the zones. There was no significant difference between species in their use of the zones. However, each individual zone was subject to differential use by the fish. Owing to the extensive scale of the aquarium, we discuss the applicability of the behavioural results obtained to the natural environment in the context of the ecology of the species of fish studied. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   

17.
The marine ornamental fish trade (MOFT) is a worldwide industry that targets a remarkable quantity and diversity of reef fish species and provides an important source of revenue for exporting countries, particularly developing nations in Southeast Asia. Here we provide, for the first time, an economic assessment of the MOFT to the European Union (EU), one of the key players of the marine aquarium trade, along with the USA and Japan. Data from EUROSTAT (the European Statistical System) was analysed for the MOFT between 2000 and 2011. Results show that this industry was not affected by the economic crisis and accounted for a total of 135 million Euros during the study period. Both the UK and Indonesia have been reinforcing their importance as leading importer and exporter countries, respectively. The long‐term temporal pattern of the MOFT by EU and non‐EU countries is described, as well as its diversity and evenness between importing and exporting countries. The present economic assessment also identifies the key players of this industry, and ultimately contributes to management and conservation practices that may enhance the sustainable use of world's coral reefs.  相似文献   

18.
  • 1. Trap fishing is widespread on coral reefs but the sustainability of this practice is causing concern because it is efficient and unselective. The effects of trap fishing were investigated by comparing fish assemblages among six Caribbean islands subject to different trapping pressures. These ranged from none in Bonaire and Saba increasing through Puerto Rico, St Lucia, Dominica and Jamaica respectively.
  • 2. Fish were censused at depths of 5 m and 15 m on fore‐reef slopes by counting the numbers within replicate 10 m diameter areas for 15 min. Between 64 and 1375 counts were made in each country.
  • 3. In St Lucia and Jamaica abundance of fish censused on the reef was compared to representation in traps which were visually sampled underwater in the area of fish counts. Twenty‐three traps were sampled in Jamaica and 75 in St Lucia. For some comparisons between these islands, St Lucian sampling effort was reduced to that of Jamaica (23 traps and 112 counts) by randomly sub‐sampling 10 times.
  • 4. Traps contained 54 different species in St Lucia and 22 in Jamaica, while there were 90 and 57 respectively in counts. After reducing St Lucian sampling effort to Jamaican levels, an average of 35 species were found in traps and 70 seen in counts. Of these, 76% in St Lucia and 73% in Jamaica were relatively more abundant in traps than they were on the reef.
  • 5. Species were considered to be highly susceptible to trapping if the ratio of their abundance in traps compared to that on the reef exceeded 3:1. Trapping pressure was approximately three and a half times greater in Jamaica than St Lucia. After equalizing sampling effort, there was an average of 16 highly trappable species in St Lucia compared to 13 in Jamaica. Species did not always appear highly trappable in both countries. Eleven of St Lucia's highly trappable species were absent from Jamaica (falling to 8.5 on average after equalizing sampling effort), but none vice versa, suggesting that trapping may have contributed to their absence or rarity on Jamaican reefs.
  • 6. The Tetraodontiformes, which include many non‐target species, were particularly susceptible to trapping in both countries. Their abundance in the six islands censused was inversely related to trap fishing pressure, as was that of two other non‐target families, butterflyfish (Chaetodontidae) and angelfish (Pomacanthidae).
  • 7. To determine whether fish that are common in traps in St Lucia are reaching sexual maturity before capture, size frequency data for 23 species from a sample of trap catches were gathered and examined for their state of maturity. In seven species, more than a third of 705 trapped fish were immature, indicating that trap fishing causes growth over‐fishing (premature removal of fish), and calling into question the sustainability of yields for these species.
  • 8. In conclusion, at the intensities seen in this study, trap fisheries cause serious over‐fishing, reduce biodiversity, and alter ecosystem structure. While commonly perceived as low impact, coral reef trap fisheries in the Caribbean and further afield, need tighter regulation and control.
Copyright © 2006 John Wiley & Sons, Ltd.  相似文献   

19.
Extensive and unregulated harvest of marine ornamental fishes can lead to localized depletion of target species and habitat degradation from inappropriate collecting techniques. One potential solution to these problems is the creation of marine reserves where fishing is prohibited. Marine reserves have been shown to increase fish abundance and protect ecosystems from habitat destruction associated with fishing. If protective areas are to be effective, they must include the diversity of habitats necessary to accommodate the wide range of fish species that are of interest to the marine ornamental fish trade.Fish assemblages with high diversity and abundance are often associated with habitats of high structural complexity. A relationship between fish size and reef complexity suggests the importance of shelter as a refuge for certain fishes in avoiding predation. Many species tend to aggregate to spawn in structurally complex habitats to reduce their risk of predation. Closing of spawning areas during aggregation periods has been shown to be a highly effective management strategy for these species. The limited home ranges and high degree of habitat specificity associated with many marine ornamental fishes should make marine reserves a highly effective strategy for managing these resources.  相似文献   

20.
ABSTRACT

In the hatchery production of aquatic animals for aquaculture, livefoods such as diatoms; rotifer, Brachionus plicatilis and brine shrimp, Artemia salina, have been used throughout the world. However, such production requires large facilities, maintenance expenses, and labor to produce a desired amount of live foods constantly and reliably. Also, the nutritive value of planktonic organisms is occasionally variable, indicating that the dietary quality of these live foods varies with the content of n-3 highly unsaturated fatty acid (n-3 HUFA). Therefore it is necessary to develop microparticulate diets as a substitute for live foods to further increase theproductivity of seed for fish culture. The nutritional components of microparticulate diets for fish larvae should be determined on the basis of requirements of the larval fish for proteins and amino acids, lipids and fatty acids, carbohydrates, vitamins, and minerals. Moreover, the efficient development of microparticulate diets for the fish larvae has promoted the improvement of nutritional requirement studies. The present reviewconcerning the nutrition of marine fish larvae focuses on the proteins, amino acids, peptides, fatty acids, phospholipids, depigmentation of flatfish, stress tolerance of lipids, incorporation of HUFA in neural tissues, HUFA in egg and larvae, HUFA enrichment of live food, carbohydrates, vitamins, energy source during embryo and larval stages, enzyme supplement in microparticulate diets, and application of microparticulate diets inaquaculture.  相似文献   

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