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Economic performance of a single hooks & line unit based on the operation per day by 4 units in AR sites and 12 units in NAR sites in 4 villages.
Source publication
The economics of fishery from artificial reef (AR) and non-artificial reef (NAR) sites by gillnet and hooks & line was studied during 2007-08 from 11 fishing villages in 6 coastal districts of Tamil Nadu. The Tamil Nadu State Fisheries Department fabricated and deployed the reefs under the technical guidance of the Central Marine Fisheries Research...
Context in source publication
Citations
... This occurs because ARs often attract more fish from surrounding habitats than they produce themselves, which can contribute to decreased fish abundance in nearby natural habitats (Matthews, 1985;Simon et al., 2011). ARs are effective at attracting and concentrating commercially-important species, including highly migratory species (Pears and Williams, 2005;Schroepfer and Szedlmayer, 2006), and numerous studies around the world have recorded increased short term catch rates and economic gains associated with ARs for both commercial and recreational fishers (Korea: Kim et al., 1994;Taiwan: Lin and Su, 1994;Philippines: Chou, 1997;Portugal: Santos and Monteiro, 1998;Iran: (Azhdari et al., 2012); India: Kasim et al., 2013;Australia: Keller et al., 2017). In the long term, these increased catch rates can contribute to regional overfishing, however (see paragraph below). ...
Artificial reef (AR) deployment has increased dramatically in the Arabian Gulf in recent years, and will likely continue as Gulf nations continue to develop their coastlines and expand fisheries. Unfortunately, there is little publicly-available information about AR programs in the Gulf, including information about management goals and program success. ARs can provide economic, social and ecological benefits, but they also have underappreciated risks associated with them. Benefits include increasing short-term catch rates for fisheries, increasing tourism, enhancing and protecting biodiversity and providing ecological services. Risks include exacerbating regional overfishing in the long-term, facilitating the spread of invasive species, altering benthic habitat around the AR, contributing to marine pollution and creating habitats that are “sinks” for larval fish. This paper provides recommendations for managers that are considering whether to initiate AR programs in the Arabian Gulf. Deployment of ARs should not be used as an excuse to allow the destruction or degradation of natural habitat, since ARs are not surrogates of natural habitat. Managers should define clear, explicit management goals in the planning stages of the reef project, and then design and deploy the reef to meet those particular goals. Managers should also set quantifiable objectives for each goal, and implement long-term monitoring programs to determine whether the reef is successful in meeting its goals. Finally, managers should disseminate the results of the monitoring program and share “lessons learned”. Implementation of these recommendations will help to guide future sustainable AR programs in the Arabian Gulf and elsewhere.
... Nine studies compared economic values related to MMS with those from non-MMS sites, six of which recorded higher economic values on MMS than on adjacent areas (Johns et al., 2001, Vivekanandan et al., 2006, Whitmarsh et al., 2008, Oh et al., 2008, Kasim et al., 2013, Kirkbride-Smith et al., 2016. Notably, Kasim et al. (2013) found that the revenues of commercial fishers in India were over twice as high on artificial reefs compared to non-artificial reef areas, whilst Johns et al. (2001) observed that recreational divers in South-East Florida were willing to pay over twice as much to protect natural reefs (USD 229.3 million/year) than to protect a shipwreck (USD 85.1 million/year). ...
... Nine studies compared economic values related to MMS with those from non-MMS sites, six of which recorded higher economic values on MMS than on adjacent areas (Johns et al., 2001, Vivekanandan et al., 2006, Whitmarsh et al., 2008, Oh et al., 2008, Kasim et al., 2013, Kirkbride-Smith et al., 2016. Notably, Kasim et al. (2013) found that the revenues of commercial fishers in India were over twice as high on artificial reefs compared to non-artificial reef areas, whilst Johns et al. (2001) observed that recreational divers in South-East Florida were willing to pay over twice as much to protect natural reefs (USD 229.3 million/year) than to protect a shipwreck (USD 85.1 million/year). However, Huth et al. (2015) found that dive tourists in Florida had a higher willingness to pay for a dive trip to a shipwreck (USD 368) than to natural reefs (USD 300), whilst Islam et al. (2014) found that the monthly fishing income from artisanal fishers on an artificial reef in Malaysia was lower than on adjacent natural reefs. ...
Man-made marine structures (MMS) are commonly used to describe any artificial structure in the marine environment, encompassing oil and gas infrastructure and pipelines, artificial reefs, jetties, piers and shipwrecks. MMS are increasingly proposed to address issues facing marine planners, including augmenting fish stocks through the creation of artificial reefs and the repurposing of redundant offshore oil and gas infrastructure (‘rigs to reefs’). Marine spatial planning is a highly contested process, characterised by multiple stakeholders with often divergent priorities due to competing objectives and values. Understanding stakeholder perspectives in relation to MMS is therefore critical in formulating appropriate policies. This review presents the first systematic and comprehensive integration of information from academic journals and ‘grey’ literature relating to social and economic values and perceptions of MMS. The review identifies that, despite advocacy for research on social and economic values of MMS, there are significant gaps in knowledge, in particular relating to comparative assessments of stakeholder values across different types of MMS. Priority areas for future research are highlighted.
... India, AFHs are deployed to improve the fishery resources and, thus, to improve the fish catch for the traditional and motorized fishermen [3][4][5]. The specific studies on the habitat ecology, habitat environment and species distribution are potential areas for research in India. ...
In this study, fish assemblages on deployed artificial fish habitats and natural rocky habitats were compared one-year post-deployment in Zuari estuary, southwest coast of India employing underwater visual census. Comparisons demonstrated significant differences in fish species composition between artificial fish habitats and natural rocky habitats. Within the artificial fish habitats, the habitats located at deeper regions indicated high richness, diversity and species abundance. The rich and diverse fish assemblages on deeper artificial fish habitats might be a result of isolated location, species behavioral preferences on feeding and shelter and complexity of the habitat
... Previous studies on the economic performance of fishing units employed different indicators like net -benefit earnings ratio, rate of return (LeRy et al., 1999;Tietze et al., 2001), net returns (Panikkar et al., 1994;Kasim et al., 2013), capital productivity and labour productivity (Narayanakumar et al., 2009;Aswathy et al., 2011). In this study various indicators like operating ratio, net benefit-earnings ratio, internal rate of return (IRR) and benefit-cost ratio (BCR) were used to analyse the economic and financial performance of purse seiners operated in Karwar Harbour. ...
ABSTRACT
The techno-economic and financial performance of mechanised purse seiners and trawlers operating in Karwar Fishing
Harbour was compared using various indicators. The average diesel consumption per trip was 179 l for purse seiners and
79 l for trawlers. The average operating cost and gross revenue per trip were `21,818 and `44,383 respectively for
purse seiners and `4,803 and `6,571 respectively for trawlers. Oilsardines and mackerels contributed more than 85% of the
catch of purse seiners whereas shrimps and flatfishes contributed nearly 50% of the catch of trawlers. Capital productivity
was higher (operating ratio - 0.49) for purse seiners than trawlers (operating ratio - 0.73). The economic and financial
performance indicators like net benefit-earnings ratio (0.43), benefit-cost (BC) ratio (1.75) and internal rate of return, IRR
(117%) were higher for purse seiners which suggested that the investment on purse seiners is a more viable undertaking
when compared to trawlers in the location.
Keywords: Economic performance, Internal rate of return, Net-benefit earnings ratio, Operating ratio
Artificial reefs have been widely deployed with the intention of increasing fish habitat, enhancing recreational fishery opportunities and providing socio-economic benefits to surrounding communities. Substantial work has been done to understand the ecology of artificial reefs but the efficacy of artificial reefs as a management tool hinges on socioecological feedbacks that are not well understood. Socioecological feedbacks are difficult to discern because they depend on multiple and complex interactions between fish, fishers, managers and habitats. To better understand the net effects of artificial reefs on recreational fisheries, we conducted a literature review to catalogue effects and feedbacks of artificial reefs. Our global synthesis revealed that artificial reefs may result in a net negative effect on fish populations, at least in the short-term, as catch-driven effects bolstering socio-economic objectives occur more often or at greater intensities than positive biological effects. We have highlighted important effects of artificial reefs and feedbacks that need to be accounted for when considering their deployment in fishery management. There may be unintended consequences if biological benefits from habitat-to- fish and fish-to- fish feedbacks are outweighed by population losses due to greater socio-economic benefits from fish-to- fisher feed-backs. Taken in concert with their semi- permanent nature and apparent popularity with stakeholders, a view emerges of artificial reefs possibly functioning as a ‘social-ecological trap’. This work emphasizes the need for robust assessments of the effects of artificial reefs, as well as more formal decision science approaches for implementing of these structures.
Artificial Reefs (AR) show a wide diversity and vary in their construction materials, shape and purpose, as illustrated by the present analysis of 127 scientific papers. AR have been deployed for different purposes, including fisheries improvement, ecological restoration of marine habitats, coastal protection or purely scientific research. Statistical analyses using 67 variables allow us to characterize the design, objectives and monitoring strategies used for AR. An effectiveness indicator comprised of three categories (low, moderate and high) was adapted from previous studies and applied to the present dataset in terms of the objectives defined in each scientific paper. The effectiveness of various monitoring approaches was investigated and recommendations were formulated regarding environmental parameters and the assessment of ecological processes as a function of AR type. These analyses showed that inert materials like concrete associated with biomimetic designs increase the benefits of reefs to the local environment. This study also compared effectiveness between the different economic, ecological or scientific objectives of AR projects and reveals that fisheries projects showed the highest efficiencies but points out the weakness of environmental assessments for this type of project. In conclusion, the analyses presented here highlight the need to use a panel of complementary monitoring techniques, independently of the initial purpose of the artificial structures, to properly assess the impact of such structures on the local environment. It is recommended to adopt approaches that associate structural and functional ecology. An improved characterisation of the role of AR should be integrated into future assessments, taking into account the complex framework of ecosystem structure and trophic relationships.
Fisheries enhancement initiatives are a potentially useful tool for managers to supplement traditional approaches. Habitat‐based enhancements often deploy artificial reefs with the aim to increase the available structure to augment local production, yet current assessment approaches make it difficult to assess whether these reefs achieve pre‐deployment goals. This makes it hard for managers to determine whether artificial reefs could improve their fishery outputs, potentially leading to missed opportunities and reduced production. We reviewed 270 research articles to determine whether existing monitoring studies identify whether artificial reefs meet their pre‐deployment goals, thereby providing some evidence of their suitability for certain fisheries. We found only 62% of these studies clearly articulated the original goals of the reef. Goals were qualitative, and most studies were conducted over insufficient time frames to allow for ecological communities to stabilize and mature. It is therefore difficult to determine the success or failure of many artificial reefs in addressing the management issues for which they were deployed. In the light of these findings, we think the setting of explicit quantitative goals (which may be biological, social or economic), and monitoring the performance of reefs against these goals, could stimulate the broader application of artificial reefs in fisheries management strategies. Such an approach has been successfully adopted in aquaculture‐based fisheries enhancement, and we explain how current evaluation methods such as harvest strategies can be easily adapted to quantitatively monitor artificial reef performance.
Artificial reefs are used to protect coastal habitats and rebuild fisheries. This engineering approach to fisheries management has gained popularity in many coastal areas, including China. In Shandong province alone, over USD 50 million were invested in artificial reefs during 2005–2013. Have artificial reefs achieved their biological and economic objectives? We compared reef and control sites in terms of catch and value per unit effort and average body length across species, based on surveys carried out during 2012–2013. We found that in aggregate, with all fish and invertebrates combined, artificial reefs did not improve the overall catches or revenues. Instead, seasonal fluctuations were prominent. However, when we allow for species-specific differences and focus on the common fish species, we find that an artificial reef can increase the catch and value per unit effort on average by approximately 40% compared to the control sites. The difference between these contrasting results occurs because some of the dominant species that comprise the bulk of the catches did not benefit from the reef, while many of the less dominant ones did so. This underlines the importance of being specific about what is meant by “benefiting fisheries” when evaluating artificial reefs, as well as when the objectives of reef projects are formulated in the first place. The positive effects of artificial reefs can be caused by the reefs themselves and by their influence on fishing patterns. Our study was not designed to separate these effects but we suggest that in Shandong, restrictions on fishing access may have been as important as the presence of the reef itself.
The depletion of fishery resources and their habitats on account of fishing, pollution and other anthropogenic activities necessitates their replenishment by some strategic management approaches. Artificial Reef (AR) is a kind of artificial fish habitat which provides living, hiding and breeding places for aquatic organisms and thereby augmenting the biodiversity and abundance of fishery resources. In particular, the installation of ARs along coastal regions could bring down the fishing pressure from mechanised sectors and thus support the small scale traditional fisheries. Since the management based on AR is not species specific but effective for all aquatic organisms in the ecosystem, it allows fisheries managers to move from a single species framework to Ecosystem Based Fisheries Management (EBFM) in the long run. Being a tropical coastal nation, India has also initiated trials on AR deployment. However, these studies so far are limited to the design, construction and performance of AR. In this review paper, the historical AR initiatives in India are critically analysed and potential areas for research and development that the country can focus on are discussed particularly in the perspective of supplementing the inshore fisheries.
