Integrated coastal management of Dakshina Kannada and Udupi--a case study

A concerted effort is needed to achieve sustainable and equitable development of the coastal regions of India. In this direction government of India has initiated the processes of putting in place integrated coastal management through the Department of Ocean Development. The study area, an ecologically sensitive region is developing at a very fast rate, however, the development has neither been uniform nor spread over the entire region, rather it has been concentrated in Dakshina Kannada district alone. Innovative technologies have been introduced in the area of capture and culture fisheries and also there has been major industrial development. These two aspects have led to user-user conflict and concern for environmental degradation. The study reveals an urgent need to put in place processes leading to integrated coastal management. Cause and effects have been discussed and possible remedies suggested.

Positive reform of tuna farm diving in South Australia in response to government intervention

OBJECTIVES

Much of the tuna harvested in South Australia since 1990 has involved "farming" techniques requiring the use of divers. From 1993 to 1995, 17 divers from this industry were treated for decompression illness (DCI). In response, the State Government introduced corrective strategies. A decrease in the number of divers presenting for treatment was subsequently recorded. Consequently, the hypothesis was tested that the government intervention resulted in a decrease in the incidence of DCI in the industry and an improved clinical outcome of divers with DCI.

METHODS

The incidence of treated DCI in tuna farm divers was estimated from the number of divers with DCI treated and the number of dives undertaken extrapolated from a survey of the industry in 1997-8. General health was measured in the tuna farm diving population by a valid and reliable self assessment questionnaire. The outcome of the divers treated for DCI was analysed with a modified clinical severity scoring system.

RESULTS

The apparent incidence of treated DCI has decreased in tuna farm divers since the government intervention. The evidence supports a truly decreased incidence rather than underreporting. The general health of the tuna farm divers was skewed towards the asymptomatic end of the range, although health scores indicative of DCI were reported after 1.7% of the dives that did not result in recognised DCI. The clinical outcome of the divers treated since the intervention has improved, possibly because of earlier recognition of the disease and hence less time spent diving while having DCI.

CONCLUSIONS

The government intervention in the tuna industry in South Australia has resulted in a reduced incidence of DCI in the industry.

The great scallop: an endangered species

The great scallop is a highly valued marine species. It makes its home on rocky seabeds around the British Isles and has been heavily exploited. Fears that natural stocks are showing signs of over fishing are being remedied by strict enforcement of fisheries legislation and by the development of stock enhancement practices.

Population dynamics and stock assessment for Octopus maya (Cephalopoda: Octopodidae) fishery in the Campeche Bank, Gulf of Mexico

The octopus (Octopus maya) is one of the most important fish resources in the Mexican Gulf of Mexico with a mean annual yield of 9000 ton, and a reasonable number of jobs created; O. maya represents 80% of the total octopus catch, followed by Octopus vulgaris. There are two artisanal fleets based on Octopus maya and a middle-size fleet that covers both species. Catch-at-length structured data from the artisanal fleets, for the 1994 season (August 1st to December 15th) were used to analyze the O. maya population dynamics and stock and to estimate the current level of exploitation. Von Bertalanffy growth parameters were: L infinity = 252 mm, mantle length; K = 1.4 year-1; oscillation parameters C = 1.0, WP = 0.6; and tz = 0.842 years. A rough estimate of natural mortality was M = 2.2, total mortality from catch curve Z = 8.77, and exploitation rate F/Z = 0.75. This last value suggests an intensive exploitation, even when yield per recruit analysis indicates both fleets may increase the minimum legal size on about 10% to increase yields. The length-based VPA also shows that the stock is being exploited under its maximum acceptable biological limit. These apparently contradictory results are explained by biological and behavioral characteristics of this species. Because most females die after reproduction, a new gross estimation of natural mortality was computed as M = 3.3. The new estimate of exploitation rate was F/Z = 0.57. This new value coincides with results from the length-VPA and the Thompson and Bell methods, the former suggesting that a reduction of 20% in fishing mortality may provide larger yields. This fishery resource is fully exploited and current management measures must be revised to sustain and probably optimize yields.

Variable effort fishing models in random environments

We study the growth of populations in a random environment subjected to variable effort fishing policies. The models used are stochastic differential equations and the environmental fluctuations may either affect an intrinsic growth parameter or be of the additive noise type. Density-dependent natural growth and fishing policies are of very general form so that our results will be model independent. We obtain conditions on the fishing policies for non-extinction and for non-fixation at the carrying capacity that are very similar to the conditions obtained for the corresponding deterministic model. We also obtain conditions for the existence of stationary distributions (as well as expressions for such distributions) very similar to conditions for the existence of an equilibrium in the corresponding deterministic model. The results obtained provide minimal requirements for the choice of a wise density-dependent fishing policy.

Species identification using genetic tools: the value of nuclear and mitochondrial gene sequences in whale conservation

DNA sequence analysis is a powerful tool for identifying the source of samples thought to be derived from threatened or endangered species. Analysis of mitochondrial DNA (mtDNA) from retail whale meat markets has shown consistently that the expected baleen whale in these markets, the minke whale, makes up only about half the products analyzed. The other products are either unregulated small toothed whales like dolphins or are protected baleen whales such as humpback, Bryde's, fin, or blue whales. Independent verification of such mtDNA identifications requires analysis of nuclear genetic loci, but this is technically more difficult than standard mtDNA sequencing. In addition, evolution of species-specific sequences (i.e., fixation of sequence differences to produce reciprocally monophyletic gene trees) is slower in nuclear than in mitochondrial genes primarily because genetic drift is slower at nuclear loci. When will use of nuclear sequences allow forensic DNA identification? Comparison of neutral theories of coalescence of mitochondrial and nuclear loci suggests a simple rule of thumb. The "three-times rule" suggests that phylogenetic sorting at nuclear loci is likely to produce species-specific sequences when mitochondrial alleles are reciprocally monophyletic and the branches leading to the mtDNA sequences of a species are three times longer than the average difference observed within species. A preliminary test of the three-times rule, which depends on many assumptions about the species and genes involved, suggests that blue and fin whales should have species-specific sequences at most neutral nuclear loci, whereas humpback and fin whales should show species-specific sequences at fewer nuclear loci. Partial sequences of actin introns from these species confirm the predictions of the three-times rule and show that blue and fin whales are reciprocally monophyletic at this locus. These intron sequences are thus good tools for the identification of these species and will afford a chance to identify putative hybrid blue/fin whales thought to have entered the retail market after 1989.

National legislation in Great Britain for the control of fish diseases

The Diseases of Fish Act 1937 of Great Britain is almost certainly the longest-standing example of national legislation specifically devised to control fish diseases. It was introduced in response to several outbreaks of furunculosis disease in wild salmon and other fish species in the rivers of England, Wales and Scotland, which were attributed to the importation of infected live rainbow trout from Germany. The Act totally prohibited the importation of live salmonids into Great Britain, and made it illegal to import salmonid ova and all live freshwater fish species without a licence. The Act also provided powers for authorised persons to enter onto any land to confiscate any fish, ova, foodstuff or articles suspected to have been illegally imported into Great Britain. Moreover, the Act enabled any disease to be designated as 'notifiable', meaning that even the suspicion of its presence in any waters must be reported to the official services. This legislation was eventually amended and extended by the Diseases of Fish Act 1983 to make it a legal requirement for all fish-farming businesses to become registered with the official services, and to maintain records of the movement of fish and fish ova into and from their sites. In 1986, additional powers were introduced under the Animal Health Act 1981 to limit the importation of dead, ungutted salmonid fish. In 1993, the legislation was amended to remove any legal conflict with European Economic Community Council Directive 91/67/EEC. In addition, the Diseases of Fish (Control) Regulations have since been passed so that new European Union rules for the control of infectious salmon anaemia, viral haemorrhagic septicaemia and infectious haematopoietic necrosis may be enforced nationally.

Review of disease control in aquaculture in the Republic of South Africa

The disease control measures in respect of domestic and wildlife aquatic species in the Republic of South Africa (RSA) are shared between two Directorates in the Department of Agriculture. The Directorate of Animal Health is responsible for disease control measures in respect of Salmonidae, while the Directorate of Plant and Quality Control regulates the introduction of exotic and unwanted aquatic species into the RSA. The activities and interests of commercial aquaculture are coordinated through the South African Aquaculture Organization and a national coordinating committee under the control of the national Department of Agriculture. Four diseases of trout are notifiable under the terms of the Animal Diseases Act (Act 35 of 1984), namely viral haemorrhagic septicaemia, infectious pancreatic necrosis, infectious haematopoietic necrosis and bacterial kidney disease. The zoosanitary measures in respect of these diseases require State intervention after detection of occurrence. Sampling procedures for the diagnosis of diseases, maintenance of the disease-free status of trout farms accredited for export purposes and requirements for the import of ova are based on the standards recommended in the International Aquatic Animal Health Code of the Office International des Epizooties. Zoosanitary control of other aquatic species not related to aquaculture--especially ornamental fish--may be unnecessary. An embargo, through existing legislation on the importation of unwanted species, has been the only means of protecting inland species. The author concludes by evaluating the need for, and the feasibility of, additional legislation for the zoosanitary control of other aquatic species.

Synopsis of freshwater aquaculture legislation in Germany since national reunification

Under German law, federal ministries are responsible for preparing legislation, while federal states (Länder) are responsible for applying the legislation. The author describes the system, contrasting it with the situation in former East Germany, where preparation and application of legislation were controlled centrally. The author also describes the various inland water fisheries Acts and regulations of the federal states of former West Germany which apply to aquaculture. There is a discussion of the impact on German freshwater aquaculture of the Federal Water Act, the Waste Water Levies Act, the Nature Conservation and Protection Act, the Conservation of Species Regulation, the Animal Welfare Act, the Fisheries Acts of the Länder, the Drug Act, the Animal Epidemic Act and the Fish Epidemics Regulation. The impact of this legislation varies considerably, and the extent of application is discussed. The economic changes in freshwater fish production are briefly summarised and their causes analysed.

Chilean legislation for the control of diseases of aquatic species

The Political Constitution of Chile establishes the right of the people to live in an environment which is free from contamination. The State has a duty to uphold this right and to preserve nature. With the aim of reconciling this constitutional guarantee with the pursuit of profitable economic activities, the concept of 'sustainable development' has been promoted. This mechanism makes it possible to use natural resources and the environment in a rational, effective and efficient manner both at present and in the future, and led to the promulgation of the General Law of Fisheries and Aquaculture No. 18,892 of 6 September 1991 and its amendments. This law regulates national fisheries and aquaculture activities throughout the country, and contains eleven regulations applicable to aquaculture. These regulations form a complete procedure of action relevant to the importation of aquatic species, to applicants for aquaculture concessions and authorisations, to the operation of these concessions and authorisations, and to ocean ranching systems. Due to the complexity of these regulations, important rules are still under study, while the remaining texts come into force on 1 September 1996. Formulating these rules involves consideration of current national and international regulations, the experience of farmers, the results of technical and scientific research, and bibliographical data. These regulations will form the cornerstone of Children aquaculture policy in confronting the challenges of the next century.

Finfish health protection regulations in Canada

The Fish Health Protection Regulations (FHPR) in Canada were implemented under the Fisheries Act in 1977. These Regulations are based on the principle of controlling the movement of fish and eggs carrying infectious diseases of concern. Source facilities require a history of inspections to demonstrate the absence of named diseases and disease agents. Since the FHPR were implemented, no disease agents of concern are known to have been transferred with egg and fish shipments approved under these Regulations. Changes to the Regulations are needed, however, for the following reasons: -to incorporate new knowledge on salmonid diseases and their distribution -to cover transfers of other finfish species which present a risk of introducing or spreading infectious disease agents to Canada or between provinces -to eliminate unnecessary controls -to specify the new authorities needed to protect effectively the health of fisheries resources -to reflect emerging international standards. The author describes the authority, administration, requirements and procedures for the current FHPR and the corresponding 'Manual of Compliance', and the proposed amendments to the Regulations and Manual. Issues related to fish health protection in Canada are discussed, including the following: -industry concerns with the FHPR -the need for quality assurance/quality control guidelines for diagnostic laboratories -consistency with international trade standards -the need to consider genetic and ecological factors, as well as fish health, when assessing impacts of introductions and transfers.

Quarantine of aquatic animals in Australia

Australia is free from many significant diseases of aquatic animals. Quarantine policies for aquatic animals and aquatic animal products are designed to meet the international trade obligations of Australia, while preventing the entry of pests and diseases. These policies are supported by measures to prevent the introduction of aquatic species which would have deleterious effects on the environment. The Australian approach to quarantine--utilising objective risk analysis, where possible--is more difficult to apply to aquatic species than to terrestrial animals, as it is hard to identify and quantify risks when much of the relevant disease and epidemiological information is unavailable. Other than ornamental fish, for which stringent quarantine restrictions apply, involving isolation in quarantine premises, there have been no commercial importations of live aquatic species into Australia over the past decade. The onerous requirements for detailed analysis of disease risks and environmental implications have tended to deter potential importers. For many years, specific controls--based on risk analysis--have also been placed on the importation of products such as oysters in the shell, salmonid products, and feeds and meals of aquatic animal origin. A major review of quarantine requirements has been commissioned.

[Legal and animal welfare aspects of the killing of fish]

The selection of methods for killing fish is determined by the number of fish to be killed, their utilization and the existing laws. No regulations exist for killing non-food fish. The methods for killing food-fish, however, are stipulated in a regulation from 1936. Mechanical or electrical stunning is obligatory except for flatfish and eel. Single fish should be stunned by a blow on the head, followed immediately by slaughtering or bleeding to be sure that the fish is really dead. When larger numbers of fish should be killed for food production only electrical methods are allowed as alternative. Chemicals can be used for killing non-food fish, the non-pollutant destruction of dead fish and chemical-contaminated water, however, has to be guaranteed. The methods are discussed with respect to practicability and animal welfare.

Programs of safety surveillance and control of fishery products

In the United States, fishery product safety at the federal level falls primarily under the authority of the Food and Drug Administration. However, other federal agencies play an important role. The Environmental Protection Agency is responsible for setting and recommending pesticide limits in seafood, and the National Marine Fisheries Service operates a voluntary inspection program. The Centers for Disease Control is responsible for the collection and evaluation of data characterizing the source of seafood-borne illness. Individual states also play a dominant role in the control of seafood-borne risk because of the important differences in consumption and contaminant levels across regions of the country. State public health, environmental protection, and resource management agencies have developed programs designed to mitigate that risk. Because of the complication and variability of the fishery industry, an effective safety system can be developed based on partnership among federal and state agencies, in which state governments retain the dominant role and the federal government develops and updates guidance programs and provides oversight. The international community has developed practices and protocols impacting the regulation of seafood safety in the United States. In view of developing trade agreements, the international community should address the criteria of setting equivalent contaminant levels and consider the option of establishing import contract criteria for fishery products.

Species preservations in an optimal harvest model with random prices

In this paper, we consider an optimal harvest model in which the objective is to maximize the expected return. The unit price of biomass is assumed constant until a random time when the price increases by a given amount. Furthermore, due to obvious environmental protection requirements, it is assumed that the fishery population is bounded from below for all time so as to reduce the danger of species extinction. Clearly, this problem is an optimal control problem in which a random parameter is involved. However, due to its special structure, it is shown that the problem is convertible into a deterministic optimal control problem and hence is solvable by an existing optimal control software package, MISER. The practical implication of several computed results obtained by this approach is discussed. They are also compared with other related results in the literature.