Destructive Fishing Methods Research Articles

Use and management of seagrass ecosystems in southwestern Madagascar

Madagascar’s seagrass meadows are among the least-studied ecosystems in the western Indian Ocean region. To facilitate sustainable management, understanding the traditional uses of seagrass areas in relation to current management policies is necessary. This study assessed the uses of, and policies relevant to, seagrass ecosystems off southwestern Madagascar. We interviewed 131 community members in five coastal villages around the Bay of Ranobe in Toliara Province. Answers to the survey revealed a good level of awareness of seagrass, though 55% of respondents perceived the status of the seagrass areas as deteriorating. Opinions varied on the source or degree of threats to seagrass, but 74.8% of respondents suggested destructive fishing methods or other factors, including natural phenomena and animal grazing. The responses highlight that seagrass meadows serve as areas important for fishing, seaweed cultivation or sea cucumber farming, and the passage of boat/pirogue transportation. There are currently no tangible policies that directly protect or manage the seagrass areas regarding these activities, although some national regulations and local management initiatives are indirectly relevant, notably no-take zones and the local-level codes known as Dina. Development and implementation of a national management plan for seagrass ecosystems is a key gap. This demands the collection of scientific data to support decision-making to ensure long-term provision of the services provided by seagrass meadows. The involvement of coastal communities in the management of seagrass ecosystems will be necessary for the success of any new policies.

Coral restoration in the Philippines: Interactions with key coastal sectors

Much work on coral restoration to date has focused on experimenting with diverse technical approaches and techniques. As the implementation of coral restoration globally increases, it is increasingly recognized that there is a need to better understand how to govern this emerging technology effectively, which requires assessing the social, economic and political contexts in which reefs are restored. This study examined the interactions (both current and potential) between the dominant economic sectors in coastal Philippines and coral restoration. Informed by ongoing coral restoration efforts in Pangasinan province, the paper draws on social data collection of the major coastal economic sectors in the province. Large-scale aquaculture of milkfish generates significant challenges to existing and new efforts at coral restoration as the industry is poorly regulated and environmentally damaging. Destructive fishing methods persist due to weak enforcement capacities and likewise pose challenges to coral restoration. Tourism, as an increasingly important economic activity in the region, potentially provides synergies between coral restoration and local economies. This study highlights that interactions between these business sectors and organisations working to protect coral reefs will go a long way to shaping the eventual governability and sustainability of coral restoration projects. Future reef restoration initiatives need to understand the interactions and dynamics of these sectors in specific contexts, and to identify strategies to manage them for the restoration interventions to work effectively and ultimately generate sustained benefits.

Effects of Coral Reef Destruction on Humans and the Environment

Coral reefs are home to a rich biodiversity and one of the most diverse ecosystems on the planet. It provides home to 35,000–60,000 species of plants and animals (over 25% of all marine life), many of which have not been described by science. It provides food, employment, and tourism to people, protecting coastal areas from storm surges; and acts as nesting grounds for many species of fish that are important for commerce. In recent years, several natural and anthropogenic disturbances have damaged the coral reefs of the world a number of events, including pollution, overfishing, destructive fishing methods, boat anchor falls, tourism, mining coral for building materials, and a warming climate, are destroying coral reefs. To reduce the destruction of coral reefs, mitigation measures, encourage sustainable fishing, following all safety precautions when visiting coral reef areas, provide alternative management plans such as coral restoration, artificial reef management, and coral nurseries to improve the coral cover in degraded areas and also increase public awareness and stewardship program related to coral reef and its associated biota, reduce plastic pollution in the ocean.

LAW ENFORCEMENT MODEL BASED ON LOCAL KNOWLEDGE AND FORMAL LAW IN SAVING CORAL REEF DESTRUCTION IN SPERMONDE ISLANDS

The purpose of this research is to describe a law enforcement model based on local knowledge and formal law in preserving coral reefs in the Spermonde Islands. The method used is a literature review. The data collection technique was carried out using the PRISMA method which resulted in inclusion of 17 journals, then were analyzed using thematic analysis techniques. The result shows that the damage happened to coral reefs in the Spermonde Islands was caused by human activities related to the use of fishing gear and destructive fishing methods which damaged coral reefs. Local knowledge combined with formal law is an effective solution as an effort to save the damage to coral reefs in the Spermonde Islands. This solution can be realized and has a good impact on the sustainability of coral ecosystems which in line with SDG'S point 14.

Seagrass restoration in a high-energy environment in the Western Indian Ocean

Although seagrass restorations have been conducted in many regions globally, restorations in high-energy wave environments are less explored. With accelerating losses of seagrass meadows globally, we also lose valuable ecosystem-based adaptations and ecosystem services, where the Western Indian Ocean is not an exception. The coast of Tanzania has only a few island shelters, creating an open exposed coast with a long wind fetch, generating strong wave exposure on the coastline. Still, seagrass meadows are present but have similar to global trends declined due to e.g. warmer ocean temperatures, coastal developments and destructive fishing methods. In view of the above challenges, there is a strong need for restoring seagrass meadows along the coast of Tanzania and the Western Indian Ocean (WIO) at large. However, restoration studies in the WIO are scarce and generally lacking in Tanzania. Studies elsewhere have shown that the success of a seagrass restoration varies significantly among trials and is to a large extent subject to the choice of a planting technique. Thus, in order to initiate the best practice for seagrass restoration in the Western Indian Ocean Region, for high-energy wave intertidal environments, we contrasted two restoration techniques, the plug and the sprig methods. We further explored different anchoring techniques and how various physical environmental factors influenced the growth and survival rates of seagrass shoots and rhizomes. We found that Syringodium isoetifolium transplants survived poorly in the sprig method (median = 0%), while the plug method demonstrated a much higher survival (median = 33.3%) for the 7 cm plug, and 66.7% for the 10 cm plug. The study also revealed a strong effect of water depth, where survival and growth parameters decreased with increased water depth. Finally, the study found a number of significant correlations, both positive and negative, between growth parameters and the measured environmental factors – and revealed that most of the measured environmental parameters were influenced by the local weather conditions and the monsoon seasonal cycling. The study illustrates that the restoration technique is strongly related to restoration success, providing clear guidance for future seagrass restorations in high-energy coasts in the Western Indian Ocean.

Anthropogenic Threats to Ecosystem Services of Maldivian Coral Reefs: Current Policies and Solutions

Healthy, biodiverse coral reefs provide many ecosystem services from both an ecological and socio-economic standpoint. Anthropogenic activity poses a threat to the capacity of coral reefs to provide ecosystem services. The vast, teeming coral reef system of the Maldives is under threat from overfishing, coral mining, destructive fishing methods, direct pollution and litter, and the unsustainable disposal of garbage in the country. The Maldivian government has implemented a number of policies to address these threats and protect local coral reef ecosystems from harm; however, these policies need to be expanded in order to more effectively and comprehensively protect local coral reefs. If the policies outlined in this paper are adopted, Maldivian coral reefs will be protected well into the future and the local population will benefit from their ecosystem services for generations to come.

Maximum Sustainable Yield Estimates from Lake Nasser Fisheries, Egypt with Special Reference to Nile Tilapia Oreochromis niloticus using ASPIC Software

The lakes’ fisheries play an important role in the Egyptian economy. Egyptian lakes face many challenges such as over-fishing, illegal and destructive fishing methods, human activities and pollution which affected the fish production from it. The lakes’ contribution to the Egyptian fish production decreased from about 50% in 80’s to the only 10% during 2017. Lake Nasser, as one of the largest artificial lakes in the world, plays a significant role in Egyptian fisheries. Its mean annual fish production is about 28,000 ton, this constituted 18% of the total fish harvested from Egyptian lakes. The catch and effort data over 15 years were collected from the lake and analyzed to assess its status and to summerize the main problems facing its development and management. Maximum Sustainable Yield of Nasser lake with special reference to the Nile tilapia, the main species in the lake, is estimated based on catch and effort data from 2003 to 2017. The computer software packages of ASPIC had been used. The surplus production model of Schaefer was applied in this study. The obtained results proved the over exploitation situation for the lake fishery and to achieve the sustainability many applicable measures are recommended.

Historical abundance and distribution of the native flat oyster (

Reefs of the flat oyster (Ostrea angasi) were once common along the southern coasts of Australia. Historical and current literature relating to O. angasi was used to identify bays and estuaries where this species once existed. In many estuaries of Western Australia, current populations are significantly lower than historical levels, including in Princess Royal Harbour and Oyster Harbour, near Albany. The main causes of the declines included overfishing, combined with the use of destructive fishing methods, such as dredging. Other factors, such as sedimentation, increased nutrient input and loss of seagrass, may have contributed to the loss of oyster reefs, and may have inhibited effective recovery. The possible impact of the protozoan pathogen Bonamia exitiosa is uncertain, although it is known to have severely affected flat oyster populations in other parts of the world. The fact that O. angasi reefs in Oyster Harbour did not recover after the fishery ceased suggests that restoration activities, aimed at restarting the ecosystem services that the oyster reefs once provided, should be undertaken. This paper suggests that the historical presence of O. angasi could be an effective starting point for prioritising potential restoration sites and details the prioritisation protocol that was used in recent restoration activities.

Ecosystem Approach to Fisheries Management works—How switching from mobile to static fishing gear improves populations of fished and non‐fished species inside a marine‐protected area

Abstract Designated using a Statutory Instrument in 2008, Lyme Bay marine‐protected area (MPA) is the UK's first and largest example of an ambitious, whole‐site approach to management, to recover and protect reef biodiversity. The whole‐site approach applies consistent management, in this case excluding bottom towed fishing, across the full 206 km2 extent of the MPA, thus protecting a mosaic of reef‐associated habitats from regular damage, while still allowing less destructive fishing methods, such as static gear, rod and line, and diving. To assess the effectiveness of this management strategy for mobile taxa and the sustainability for those taxa that continue to be targeted, Exploited and Non‐Exploited species' populations were compared inside the MPA, relative to open control sites spanning 11 of the 12 years of designation. baited remote underwater video systems (BRUVs) were deployed annually to assess mobile benthic and demersal fauna. Overall, the number of taxa significantly increased in the MPA relative to the open controls while total abundance increased in both treatments. Exploited fish showed increases in number of taxa (430%) and total abundance (370%) inside the MPA over 11 years. Likewise, but to a lesser degree in the open controls, number of taxa of commercially Exploited fish increased over time, potentially showing ‘spillover’ effects from the MPA. Non‐Exploited fish did not show such changes. Regardless of constituting the majority of the fishery value, highly valuable Exploited invertebrates showed no significant changes over time. Synthesis and applications. The Lyme Bay marine‐protected area shows importance of protecting a whole site, comprising mosaics of different benthic habitats, through protection of sessile organisms that contribute to essential fish habitats. This Ecosystem Approach to Fisheries Management can benefit and maintain sustainable fisheries and species of conservation importance.

The Importance of Involving Community Organizations for Preventing Destructive Fishing Activities in Mannar, Sri Lanka

The irresponsible destructive fishing practices with respect to the ecosystem approach have remained a major concern since the elimination of these practices has not been easy despite efforts. There is an urgent need to identify the different types of destructive fishing methods and their threats to fisheries then, to assess how the different organizations/groups/individuals confront with these threats. This study was carried out in Pesalai, a fisheries village in the Mannar district of Northern Sri Lanka in the years 2016 and 2017. The methodology employed consists of a pre-tested structured questionnaire in the field survey with a random sample of 310 fishers and a focus group discussion was conducted where 20 fishers actively participated. The results revealed that trawling net fishing, dynamite fishing, brush pile fishing, and stake net were being used extensively by the fishers. However, the use of such gears have facilitated to catch more fish and earning a high income. Resultant, the major negative impacts were gearing damages, nets damages and net loss. It is apparently found that, the majority of fisheries (93%) had faith in fisher community organizations (fisheries co-op society, the church/father and women welfare society) in terms of resolving conflicts which were raised by destructive fisheries (wrangling, argument and dissension) while 7% of the respondents have faith in the state to resolve conflicts. The fisheries believed that, the government supports for fishing activities was not well required. Hence, it is strongly concluded that the Regulations should be enforced, as a joint effort between the department of fisheries and community organizations.

Obligations and responsibilities of flag states related to IUU fishing based on ITLOS case no. advisory opinion 21 and its impacts to Indonesia

Illegal, unreported, and unregulated (IUU) fishing is still one of the biggest threats to the marine ecosystem. That is because IUU Fishing can damage a country’s national and regional efforts to manage fisheries in a sustainable manner and interface with efforts to conserve marine biodiversity. IUU Fishing has reached about 20 percent of the total world catch and up to 50 percent in some areas. IUU Fishing practices often use bonded labor, destructive fishing methods and deceptive actions to reap profits at the expense of the state’s local coastal fishing industry and the marine environment. Fisheries resources that should be available for fishermen are reduced due to IUU Fishing which can cause the collapse of local fisheries. Developing countries have proven to be very vulnerable because they have a large risk of being affected by illegal fishing, with the estimated total catch in West Africa reaching 40 percent higher than reported catches, such as exploitation rates severely almost sustainable management of marine ecosystems.

Diversity and Distribution of Fin-fish and Prawn Species Assemblages of the Catch in Five Perennial Reservoirs in Northern Province, Sri Lanka

Present study was carried out to assess the abundance and diversity of fin-fish and prawn species in the selected five reservoirs in the Northern Province, Sri Lanka. Fin-fish and prawns caught by multi-mesh gillnets, and rod and hooks, were sampled from January to December 2017. Relative abundance and diversity indices were calculated and, differences and similarities among reservoirs in different months were assessed. The hierarchical clustering was used in constructing dendrogram. Of the 27 finfish species and two freshwater prawn species identified in total, the highest number of species were observed in Muthayankattu reservoir (26 species) while Puthumurippu reservoir had the lowest (14 species). Oreochromis niloticus was the dominant species in all the reservoirs. Small reservoirs (Puthumurippu, Kalmadu and Muhathankulam) showed high Shannon-Weiner diversity index and evenness, though low in dominance index, compared to large reservoirs (Vavunikulam and Muthayankattu). Selective harvest methods, number of fishers and seasonal variation of hydro-climatic factors such as rainfall, strong wind and water level significantly influenced the diversity of fish species. Increasing fishing pressure and use of destructive fishing methods during low water level were the main contributors for diversity loss in the five perennial reservoirs studied.

Reproductive biology of the Atlantic mackerel Scomber scombrus Linnaeus, 1758 in Mediterranean coast of Sinai, Egypt.

This work aims to investigate reproductive biology of the Atlantic mackerel (Scomber scombrus L. 1758) to provide biological base for management of its fisheries in the Mediterranean coast of Sinai, Egypt. Monthly samples of S. scombrus were collected from the commercial catch in different landing sites of the Mediterranean coast of Sinai during 2019. The length-weight relation was found as W= 0.0116 L2.9556, W= 0.0077 L3.091 and W= 0.0094 L3.022715 for males, females and combined sexes respectively. Overall sex ratio (males: females) was 1: 1.4 during the period of study. Gonado- Somatic Index (GSI) of females showed that S. scombrus spawn during March, April and May, since GSI peaked in these months (6.5, 7.2 and 5.2 % respectively). The lowest value of GSI of females was recorded in October (0.05%). Lengths at first sexual maturity (Lm) were determined as 23.2 and 23.4 cm for males and females respectively. The absolute fecundity (F) was increasing with the fish length and described by a power equation: F = 0.0014 L5.6414. The relative fecundity gradually increased from 2481.8 to 7599.3 eggs per cm (average 4748.9 eggs / cm). To protect and maintain the stock of Atlantic mackerel in the Mediterranean coast of Sinai, it is recommended to ban using fishing nets of illegal mesh sizes and other destructive fishing methods which catch small fish sizes. Length at first capture should be larger than length at first sexual maturity (> 23.4 cm) and ban fishing nets targeting S. scombrus during its spawning season (from March to May).

Sustainable Fisheries Management in the Indian Ocean: The Way Forward

The Oceans cover 71% of the earth’s surface and contains 97% of the planet’s water. This is the life support system of the earth. The Ocean is the main protein supplier for the humankind. The Indian Ocean is a warm water ocean and well regulated by monsoons and currents. Large number of rivers and tributaries flow into this ocean, making it rich with minerals, seaweeds and planktons, which sustain the fish stocks. Man-made pollution and climate change can be detrimental to the sustenance of a balanced marine eco-system. Further, Illegal, Unreported and Unregulated (IUU) fishing combined with destructive fishing methods can deplete this valuable protein source. Issues and conflicts in delimitation of maritime boundaries and fishermen not respecting even internationally or bilaterally established maritime boundaries are impediments to effective fisheries management. The Indian Ocean is vast and the third largest ocean in the world. The population of the Indian Ocean is around 2.5 billion. However, we must be mindful of the need to have a sustainable ocean based economic model, that will not over exploit the finite fishery resources but will continue to provide the much-needed protein sources to this large population, not only at present times but even in the future. Non-management of fisheries by states and non-adherence to rule based maritime order by non-state actors engaged in fisheries could have ramifications on traditional and human security aspects for the region. Fishing boats and some fishermen could be involved with various maritime crime activities for monetary or ideological gains, and, depletion of fisheries resources due to overfishing can have a direct impact on human security of the Indian Ocean littorals, as the main livelihood and economic activities of the coastal populations are connected to the ocean based resources. There were many instances of the fishermen being exploited by terrorist groups. Hence the management of fisheries in a sustainable manner is important for the Indian Ocean, as the peaceful co-existence of the nations depends on the continued Blue Economic models where the fisheries is managed and harvested in a sustainable manner.

Spatially explicit action research for coastal fisheries management.

We worked with artisanal fisherfolk along the Coromandel coast in two districts of Tamil Nadu and the Union Territory of Pondicherry in South India to map and quantify catch, gear and crew details for all fishing craft along 120 km. Spatially explicit fisheries data were collected to understand the distribution of fishing effort and to identify high pressure fishing zones. Approximately 7,945 square kilometres of fishing grounds were surveyed and 3,427 fishing trips were observed using nine GPS enabled echo-sounders operated by fishermen. Data were visualised and non parametric statistical analysis revealed distinct patterns in fishing effort, high density fishing zones and large overlaps in zones between traditional, motorised and mechanised craft. Existing marine fishing regulations for the respective regions were also evaluated and violations were mapped. Results were presented in each of the villages and then in district wide meetings with community leaders to spur discussions on resource based conflicts and fisheries management. Our findings suggest that the present trajectory of resource over-exploitation, the use of destructive fishing methods combined with the lack of compliance to current regulations will lead to a collapse of the small scale fishing industry and further intensify conflicts within the community. Recommendations made by fishing community leaders are presented and their role in local fisheries management is discussed. This study is the first of its kind for this region and can easily be replicated at regional scales to develop a better understanding of the spatial extent and nature of small scale fisheries, including conflict, for the purpose of fisheries management.

When Patience Leads to Destruction: The Curious Case of Individual Time Preferences and the Adoption of Destructive Fishing Gears

The use of destructive fishing methods is a serious problem, especially for tropical and developing countries. Due to inter temporal nature of fisheries extraction activities, standard economic theory suggests that an individual's time preference can play a major role in determining the gear choice decision. Based on earlier theoretical work we identify two ways in which individual time preferences can impact the adoption of destructive extraction methods; (i) the conservation effect which posits that patient individuals (as indicated by relatively high discount factor) are less likely to use destructive extraction methods since they are more likely to account for the loss of future income that is accompanied by using these methods, (ii) the disinvestment effect which argues that patient individuals are more likely to use destructive extraction methods since they have greater investment capability.Using an agent-based model we clarify the conditions under which one of these effects is more dominant than the other one. Our model suggests that the nature of destructive gear along with the level of social dilemma determines whether patient or impatient individuals (relatively lower discount factor) are more likely to adopt such a gear. Additionally agent's beliefs regarding future resource condition and other agent's extraction level can have a major influence in some cases.

On some destructive fishing methods of Central Travancore of Kerala, India

Many destructive fishing practices are widely used at many sites of Central Travancore of Kerala, India. Most of these are indigenous methods practiced at high level to low level regions. It includes chemical poisons, plant poisons, fish traps, electric fishing etc. All these gears kill the fishes and their fries and fingerlings indiscriminately. It is an endeavor to trace out the details of these harmful fishing methods.

Dhonagoda River: Threats Investigation of River and Biodiversity for Policy Implementation

The River Dhonagoda is one of the important Rivers of Chandpur district with diverse fish biodiversity and supports livelihood for fisher’s community. The present study was conducted from January 2016 to September 2017 to determine the threats on the River Dhonagoda and fish biodiversity and to document fish species with their present conservation status both in the context of Bangladesh and global aspects. The major threats to Dhonagoda River and its fish biodiversity were found to be the illegal River encroachments, use of River bank soil, indiscriminate killing and overexploitation of fish fry and fingerling, habitat destruction, use of destructive fishing gear and methods, silt bed, water pollution and lack of proper management initiatives. A total of 56 fish species were documented belonging to 9 orders and 23 families. The most dominant order was found to be Siluriformes consisting 32% of the total fish population. Cyprinidae was found to be the richest family (21.4%). In the studied areas 15 common groups were recorded where Catfish contributes the highest percentages (32%). River-Estuary was found to be the biggest habitat for the maximum number of fishes (50%). Among the total identified fish species from the River Dhonagoda, 13 threatened fish species (19%) were recorded in which 6 species (46%) were found as Vulnerable (VU), 5 species (38%) as Endangered (EN) and 2 species (16%) as Critically Endangered (CR). To save the River and to conserve its fish biodiversity best management practices have to be adopted and strictly implemented by the proper authority.

Marine ornamental species culture: From the past to “Finding Dory”

The present article revises the major topics related to fish and coral reproduction. In particular after a short review of the ornamental trade and the destructive fishing methods that are still used in some areas, the present review revises the principal modes of fish and coral reproduction introducing the main critical bottlenecks in their captive propagation. Regarding fish these include sexing the fish, pair forming, the embryo development, the hatching process and of course the transition from an endogenous to an exogenous feeding by the larvae. As concerns corals, great attention is given to the main modes of reproduction as well as to nutrition and lightening.

A longitudinal evaluation of the Communication, Education and Public Awareness (CEPA) campaign for the Philippine crocodile Crocodylus mindorensis in northern Luzon, Philippines

The Philippine crocodile Crocodylus mindorensis is Critically Endangered and its range is restricted to a few localities in human‐dominated landscapes. Therefore, the survival of this species in the wild depends strongly on the support of local people. Communication and education are prerequisites for successful in situ conservation. Over a 12 year period, the Mabuwaya Foundation distributed posters, calendars and comic books, organized theatre shows, gave school lectures, facilitated community meetings and established a crocodile rearing station/visitor centre to mobilize local support for the conservation of the Philippine crocodile in the northern Sierra Madre in Luzon. This paper documents changes in people's awareness of and attitudes towards the conservation of the Philippine crocodile, and changes in people's behaviour in ten barangays (villages) in the municipality of San Mariano. Most people living in crocodile habitat now know that the Philippine crocodile is protected by law and support the conservation of the species in the wild. Hunting, the destruction of nests and the use of destructive fishing methods have all significantly declined in these areas. As a result of the integrated conservation programme, the Philippine crocodile population is slowly recovering.