The role of fisheries sector in the coastal fishing communities of Sri Lanka

Sri Lanka is an island country with a land area of 65 610 km2. With the declaration of the exclusive economic zone (EEZ) in 1976, the country gained sovereign rights over an ocean area of 536 000 km2 and EEZ extending from 24 to 200 nm. The continental shelf is about 26 000 km2 with an average width of around 22 km, and the coastline is 1 100 km long. The total annual fish production of Sri Lanka was 25 000 t in 1952 and 269 850 t in 1998. Major fish species caught in Sri Lankan waters are skipjack, blood fish, yellow fin tuna, mullet, shark, trevally, Spanish mackerel, prawns, lobsters. Gross domestic product (GDP) is composed of services, agriculture including forestry and fishery, manufacturing, construction and mining and quarrying. Of these, the agriculture sector contributed 21% with 2.5% coming from the fisheries subsector in 1998. In 1975, fisheries contributed Rs420 million to GDP and substantially improved to Rs24 823 million (US$382 million at 1 US$ = 64.90 Sri Lanka Rupee; source: oanda.com) in 1998. Export volume from fisheries was 3 240 t in 1985, and 11 433 t in 1998; equivalent to an export value of Rs453 mil (US$7 million) to Rs6 732 mil. (US$104 million). The fisheries sector has provided direct employment opportunities to over 115 000 people and indirect benefits to 100 000 people in related occupations such as fish processing, boat building and other equipment manufacture and trade and public sector organizations. A socioeconomic survey conducted in 1996 noted a fisher population of 83 776 with 81.7% having fishing as their sole source of income, 12.5% as their main source and 4.3% as their second source. Fish is the main and preferred source of animal protein in Sri Lanka. Fish consumption accounts for 5% of the total food consumption and per capita fish consumption was 12.77 kg in 1998. However fish constitutes a substantial share of expenditure on food because of its high domestic price. The policy of almost all fisheries projects in Sri Lanka has been to maximize the fisheries resource utilization for direct extractive purposes rather than for sustainable resource management. This short-range orientation has increased the efficiency of fishing operations through the application of advanced technologies in fish capture, leading to a shift from the traditional fishing methods to the adoption of modern fishing gear. This has led to the depletion of fishery resources, particularly in the coastal waters. Thus there is a need to adopt programmes that emphasize the development of offshore fishing and thereby reduce fishing pressure in the coastal areas. Implementation of alternative livelihood opportunities would also improve the quality of life of coastal fishers.Fishery resources, Fishery surveys, Catch/effort, Trawling, Population characteristics, Biomass, Coastal fisheries, Mathematical models, Marine fisheries, Ecosystems, Socioeconomic aspects, Artisanal fishing, Economic benefits, Fishery industry, Capture fishery economics, Fish consumption, ISW, Sri Lanka,

Small scale multispecies demersal fishery off Negombo, Sri Lanka : a study of their biology and socio-economics

The present multidiciplinary study on the demersal fishery in the Negombo area on the west coast of Sri Lanka was based on the data collected from 1992 to 1999. The prime objective of this study was to identify an appropriate management strategy for the sustainable development of the resources and the fishery. Assessments of fishery, fishery resources, economics of fishing marketing and the social aspects of the fishing community were studied in detail. The status of economically important fish stocks in the shallow and deep waters were assessed through indicator species. Lelhhnus lentjan and Leihrinus nehulosus. The demersal fishery in the area is highly diverse and the highest fishing effort is deployed by handline combined with drift gillnet boats followed by bait cage traditional handline with outboard motor boats, bottom trammel net. bottom longline. bait cage handline with inboard motor boats, and a more limited effort by bottom set gillnet and spear fishing. Handline with inboard motor boats, bottom set gillnets and spear fishing only operate during the nonmonsoon season, but fishing effort is high during this period by all gears. The multigear demersal fishery in the area is predominately conducted in the shallow waters of less than 40 m and only handlinc and bottom longline fishing are deployed in depths greater than 40m. The CPUE realised from shallow waters are low for all gears but improved with increasing fishing depth. A total of 139 fish species belonging to 68 families have been recorded in the catches but the most important families arc Lcthrinidac. Carangidac. Lutjanidac. Serranidae and Scombridac /.. nehulosus and /,. tentjim arc the dominant species. Recently the contribution of squid and cuttlefish to the total demersal catch has increased. Lcthrinds replaced the catches of Carangids as dominant fish. The three important gears, traditional bait cage handlinc. bottom longlinc and bottom trammel net fisheries arc highly interactive, harvesting the same stocks of economically important species of different but overlapping sizes. Both traditional handlinc and bottom trammel nets catch large quantities of juveniles of the indicator species inhabiting the shallow waters while bottom longlincs catch adults in deeper waters. A decline of CPUE of these interactive gears has been observed over the years. The present fishing effort of the multispccics demersal fishery has come close to the optimum, which produces the ma.ximum sustainable yield (MSY). but has long c.xcccdcd the maximum economic yield (MEY). The economically important fish resources in the shallow waters arc being overexploited and have long c.xcccdcd the optimum exploitation of 0.5 by all three main gears. The exploitation of bottom longlinc fishing has exceeded the optimum effort which produces MSY for nehulosus and both handlinc and bottom longlinc has c.xcccdcd the optimum cfTort for A. lentjan. The economics of exploitation of these two species has c.xcccdcd the MEY by all gears. The yield or the value of the catch of these two indicator species could only be improved by a 50% reduction of current effort of cither bottom trammel nets or traditional handlinc fishery, but over 60% of the households engaged in these fisheries depend entirely on fishing income. All boat/gcar combinations involved in demersal fishing c.xhibitcd good performance and generated a positive net profit, but the economic performance among them is highly variable. Profitability is highest for modem gears rather than traditional bait cage handlinc fishing. The seasonal change in fishing, according to the seasonal abundance of resources, is economically rewarding. Relatively low fixed costs plus a competitive market, high demand and low indebitness to middlemen results in a high net profit

Herding a Deluge of Good Samaritans: How GitHub Projects Respond to Increased Attention

Collaborative crowdsourcing is a well-established model of work, especially in the case of open source software development. The structure and operation of these virtual and loosely-knit teams differ from traditional organizations. As such, little is known about how their behavior may change in response to an increase in external attention. To understand these dynamics, we analyze millions of actions of thousands of contributors in over 1100 open source software projects that topped the GitHub Trending Projects page and thus experienced a large increase in attention, in comparison to a control group of projects identified through propensity score matching. In carrying out our research, we use the lens of organizational change, which considers the challenges teams face during rapid growth and how they adapt their work routines, organizational structure, and management style. We show that trending results in an explosive growth in the effective team size. However, most newcomers make only shallow and transient contributions. In response, the original team transitions towards administrative roles, responding to requests and reviewing work done by newcomers. Projects evolve towards a more distributed coordination model with newcomers becoming more central, albeit in limited ways. Additionally, teams become more modular with subgroups specializing in different aspects of the project. We discuss broader implications for collaborative crowdsourcing teams that face attention shocks.National Science Foundation Grant No. IIS-1617820.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/153786/1/Maldeniya et al. 2020.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/153786/4/Maldeniya et al. 2020 Published Version.pdfDescription of Maldeniya et al. 2020.pdf : Main ArticleDescription of Maldeniya et al. 2020 Published Version.pdf : Published Versio

Understanding communities using mobile network big data CPRsouth 2015

Understanding the strength and boundaries of human connections can help identify communities amongst a population, and is valuable knowledge for modeling disease spread, information flow, and mobility patterns. Administrative boundaries, formed by history and geography, do not necessarily reflect the actual communities or social interaction patterns within a region. In this study we employ community detection algorithms to a mobile Call Detail Records (CDR) network in Sri Lanka in order to compare natural communities existing in the interaction network against administrative regions of Sri Lanka. Additionally we explore how these communities segment into a further level of sub-communities

Using mobile network big data for land use classification CPRsouth 2015

The traditional way of generating insights on land use involve surveys and censuses, which are both infrequent as well as costly. This paper explores the potential of leveraging massive amounts of human mobile phone data to understand the spatiotemporal activity of mass populations, and by extension, provide a useful proxy for activity-based classification of land use. Understanding and monitoring land use characteristics is critical for urban planning. The study demonstrates possibilities for use of mobile network big data, and how it can be leveraged to infer three distinct land use characteristics: commercial/ economic, residential, and mixed-use

A training programme involving automatic self-transcending meditation in late-life depression: preliminary analysis of an ongoing randomised controlled trial.

: Late-life depression affects 2-6% of seniors aged 60 years and above. Patients are increasingly embracing non-pharmacological therapies, many of which have not been scientifically evaluated. This study aimed to evaluate a category of meditation, automatic self-transcending meditation (ASTM), in alleviating symptoms of depression when augmenting treatment as usual (NCT02149810). The preliminary results of an ongoing single-blind randomised controlled trial comparing a training programme involving ASTM with a wait-list control indicate that a 12-week ASTM programme may lead to significantly greater reductions in depression and anxiety severity. As such, ASTM may be an effective adjunctive therapy in the treatment of late-life depression. DECLARATION OF INTEREST: R.I.N. is Director of Research and Health Promotion for the Art of Living Foundation, Canada and supervised the staff providing ASTM training. COPYRIGHT AND USAGE: © The Royal College of Psychiatrists 2016. This is an open access article distributed under the terms of the Creative Commons Non-Commercial, No Derivatives (CC BY-NC-ND) licence

Where did you come from? : where did you go?; robust policy relevant evidence from mobile network big data

The paper discusses how output from mobility analysis based on mobile network big data (MNBD) can be aligned with the different stages of traditional forecasting frameworks familiar to transport planners and policy makers. Levels of accuracy and detail are estimated, so that mobility insights-based MNBD can be delivered. Recently developed approaches for estimating mobility are compared, and results are validated against data from traditional methods. The limitations of MNBD are presented, and alternatives are proposed to address these limitations in future work. The research aims to extend state of the art data mining to support and transform efficiencies in transportation planning

Biology, Fishery, Conservation and Management of Indian Ocean Tuna Fisheries

The focus of the study is to explore the recent trend of the world tuna fishery with special reference to the Indian Ocean tuna fisheries and its conservation and sustainable management. In the Indian Ocean, tuna catches have increased rapidly from about 179959 t in 1980 to about 832246 t in 1995. They have continued to increase up to 2005; the catch that year was 1201465 t, forming about 26% of the world catch. Since 2006 onwards there has been a decline in the volume of catches and in 2008 the catch was only 913625 t. The Principal species caught in the Indian Ocean are skipjack and yellowfin. Western Indian Ocean contributed 78.2% and eastern Indian Ocean 21.8% of the total tuna production from the Indian Ocean. The Indian Ocean stock is currently overfished and IOTC has made some recommendations for management regulations aimed at sustaining the tuna stock. Fishing operations can cause ecological impacts of different types: by catches, damage of the habitat, mortalities caused by lost or discarded gear, pollution, generation of marine debris, etc. Periodic reassessment of the tuna potential is also required with adequate inputs from exploratory surveys as well as commercial landings and this may prevent any unsustainable trends in the development of the tuna fishing industry in the Indian Ocean

Interaction between Coastal and Oceanic Ecosystems of the Western and Central Pacific Ocean through Predator-Prey Relationship Studies

The Western and Central Pacific Ocean sustains the highest tuna production in the world. This province is also characterized by many islands and a complex bathymetry that induces specific current circulation patterns with the potential to create a high degree of interaction between coastal and oceanic ecosystems. Based on a large dataset of oceanic predator stomach contents, our study used generalized linear models to explore the coastal-oceanic system interaction by analyzing predator-prey relationship. We show that reef organisms are a frequent prey of oceanic predators. Predator species such as albacore (Thunnus alalunga) and yellowfin tuna (Thunnus albacares) frequently consume reef prey with higher probability of consumption closer to land and in the western part of the Pacific Ocean. For surface-caught-predators consuming reef prey, this prey type represents about one third of the diet of predators smaller than 50 cm. The proportion decreases with increasing fish size. For predators caught at depth and consuming reef prey, the proportion varies with predator species but generally represents less than 10%. The annual consumption of reef prey by the yellowfin tuna population was estimated at 0.8±0.40CV million tonnes or 2.17×1012±0.40CV individuals. This represents 6.1%±0.17CV in weight of their diet. Our analyses identify some of the patterns of coastal-oceanic ecosystem interactions at a large scale and provides an estimate of annual consumption of reef prey by oceanic predators