Present status of the multi‐gear shrimp fishery off the west coast of Sri Lanka: gear‐based species diversity and selectivity

Catch statistics were monitored from well established small‐scale shrimp fisheries in Negombo lagoon and the adjacent coast in western Sri Lanka, in order to evaluate resource usage, gear selectivity, and spatio‐temporal dynamics of catches and CPUE. A total of 55 species, representing 35 families, including 13 shrimp species were recorded from 3546 samples obtained weekly during January 2009‐April 2010, for nine types of gear in six fishing grounds. Special emphasis was on shrimp catches: four main shrimp species, Metapenaeus dobsoni, Fenneropenaeus indicus, Parapenaeopsis coromandelica and Penaeus semisulcatus, represented 82% of the total shrimp landings. Catch per unit effort (CPUE) differed among fishing grounds, months and gear types. Species diversity differed among the gear chosen. Hierarchical cluster analysis based on presence‐absence of the species data of catches showed that clustering was based on habitat rather than on the fishing gear. Species composition analysed with a Detrended Correspondence Analyses over months and fishing grounds showed a distinction of trawl gear from the remainder of the gear operated in the lagoon. The information presented is of importance for evaluation of the present status of the shrimp fishery and for developing management strategies based on the types of gear.     

The Status of the Marine Fisheries of West Bengal Coast of the Northern Bay of Bengal and Its Management Options: A Review

Marine fishery is one of the most important sectors for both economic and social development of the country. The whole coast of West Bengal was surveyed from July 2010 to August 2012 for acquiring data on marine fishing. The secondary data were also collected from various government departments and non-government organizations. After compiling all the data a clear picture of marine fisheries in the coastal region of West Bengal was emerged. Arius spp. has the height percentage (15.16) and Yellow Fin Tuna has the lowest percentage (0.06) of landing in West Bengal coast during 2006–2012. Bombay duck and Hairtail Ribbon fish landing shows a decreasing tendency in these 7 years. As the number of mechanically powered boats are increasing in recent years, the total marine fish landing from West Bengal coast is remained more or less static. Therefore, the catch per unit effort has declined significantly in recent years (r = 0.77). So, immediate remedial measures should be taken to manage sustainably, the marine fishery sector of West Bengal.     

Redescription of Amblyomma integrum adults and immature stages

Amblyomma integrum Karsch, 1879 (Acari: Ixodidae) is one of four Amblyomma Koch, 1844 species with eyes found in southern India and Sri Lanka. The immature stages of this species were poorly described. Therefore, accurate identification is difficult. Here we re‐describe the male, female, nymph and larva of A. integrum and illustrate all the stages in greater detail for the first time. A set of diagnostic morphological characters is defined to distinguish this species from other sympatric species of eyed Amblyomma in any parasitic stage of development. Adults of A. integrum parasitize mostly various larger mammals whereas nymphs and larvae use mostly larger and medium mammals. Amblyomma integrum is recorded from India (Andhra Pradesh, Goa, Karnataka, Orissa and Tamil Nadu States) and throughout Sri Lanka.     

Initial study on catch,species composition and reproductive biology of fishes off the south‐west coast of Sri Lanka,targeted by ring nets while utilizing natural floating objects

This study evaluates the catch rates, species composition and reproductive biology of flotsam‐associated fishes targeted by ring nets off the southwest coast of Sri Lanka. Catch and number of multiday boats operating with ring nets were collected at Beruwala fishery harbor on the southwest coast of Sri Lanka, March to October 2013, by making fortnightly field visits. Fish samples were collected randomly from the unloaded ring net catches to analyze reproductive biology. Twelve fish species belonging to four major families: Scombridae, Carangidae, Coryphaenidae and Balistidae were identified in the ring net catches and five species, Decapterus russelli, Katsuwonus pelamis, Thunnus albacares, Elagatis bipinnulata and Canthidermis maculatus were predominant. An average of 25 ± 12% multiday boats landing at the Beruwala fishery harbor operated with ring nets each month, with an average monthly catch rate fluctuating from 730 ± 101 to 3924 ± 1094 kg per boat per trip. Catch rates of tunas and carangids were significantly higher than the other fish groups (anova ; d.f. = 3, P < 0.05). Total fish landed by ring nets at the Beruwala fishery harbor during the study period was 1456 tonnes. Species belonging to the family carangidae had the highest percentage contribution (46.6%) to the ring net landings followed by tuna (34%). Similar‐size individuals ranging from 24 to 31 cm were landed by ring nets, with all landed individuals belonging to K. pelamis, T. albacares and E. bipinnulata having immature gonads. The findings of this study will be useful locally as well as regionally to manage the ring net fishery and to aid in implementing measures to manage the highly migratory tuna species.     

Anopheles culicifacies Y-chromosome dimorphism indicates sibling species (B and E) with different malaria vector potential in Sri Lanka

In Sri Lanka, malaria is transmitted mainly by Anopheles culicifacies Giles sensu lato (Diptera: Culicidae). In India, this nominal taxon comprises sibling species A, B, C, D and E, distinguished by their chromosome morphology. Species B (identified by polytene chromosome sequence Xab, 2g1 + h1) is not such an efficient vector of malaria as other members of the An. culicifacies complex in India. All specimens of An. culicifacies s.l. examined from Sri Lanka possess Xab, 2g1 + h1 polytenes, previously interpreted as species B, despite their important vector status. Recently, species E was described from Rameshwaram Island (Tamil Nadu, India) between Sri Lanka and the Indian mainland, where both species B and E are sympatric. Species B and E share polytene sequence Xab, 2g1 + h1 but differ by the mitotic Y-chromosome being acrocentric in species B, submetacentric in species E, the latter implicated as vector of vivax malaria. From May 1999 to January 2000, we surveyed Y-chromosomes of male progeny from An. culicifacies Xab, 2g1 + h1 females collected from cattle bait in diverse malarious districts of Sri Lanka: Badulla, Monaragala, Puttalam and Trincomalee. Karyotypes of readable quality were obtained from 42/83 families examined, with overall proportions 24% acrocentric and 76% submetacentric Y-chromosome carriers, both types being sympatric in at least 3/4 localities sampled. By analogy with the situation on Rameshwaram Island, we interpret these observations to demonstrate widespread presence of two members of the An. culicifacies complex in Sri Lanka, their karyotypes being compatible with species B and E, the latter predominant and having greater vector potential.     

The importance of the marine ornamental reef fish trade in the wider Caribbean

The marine ornamental fish trade began in the 1930s in Sri Lanka, spread to Hawaii and the Philippines in the 1950s, and expanded to a multi-million dollar industry in the 1970s with fisheries established throughout the tropical Pacific, Indian and Atlantic Oceans. Currently, 45 countries supply global markets an estimated 14-30 million fish annually, with an import value of US$28-44 million. The largest suppliers are Indonesia and the Philippines, followed by Brazil, Maldives, Vietnam, Sri Lanka and Hawaii. In the tropical Western Atlantic, 16 countries have export fisheries, including the U.S. (Florida and Puerto Rico). The U.S. is the world's largest buyer, followed by the European Union and Japan. The global trade consists of over 1400 species of reef fishes, of which only about 25 are captive bred on a commercial scale. Damselfish, anemonefish, and angelfish constitute over 50% of the global volume; butterflyfish, wrasses, blennies, gobies, triggerfish, filcfish, hawkfishes, groupers and basselets account for 31% of the trade, and the remaining 16% is represented by 33 families. The most important fishes from the Caribbean are angelfish (six species), seahorses (two species), royal gramma, jawfish, queen triggerfish, redlip blenny, puddingwife, bluehead wrasse, and blue chromis. The Caribbean currently supplies a small percentage of the global trade in marine ornamental species, but ornamental fisheries in this region represent important emerging industries. It is critical that effective ornamental fishery management plans and regulations are developed and enforced, and fishery-dependent and fishery-independent data are collected and utilized in decision making processes to ensure sustainable ornamental fisheries throughout the region.     

Memories of ethnic violence in Sri Lanka among immigrant Tamils in the UK

This article contributes to recent studies on the relationship between ethnicity and memory in the formation of transnational communities. The focus of the article is migrant Tamils' memories of violence in Sri Lanka in 1958, in the aftermath of an act declaring Sinhala to be the sole language of administration in the country. The ways in which past violence is remembered by this overlooked older generation helps in understanding the particular impetus of the contemporary Tamil diaspora, which continues to play a key role in shaping the image of Sri Lanka abroad. Research on the formation of the diaspora must therefore be situated within a more concrete history of relations between Sinhalese and Tamils in post-independence Sri Lanka.     

Genetic relationship among the musk shrews,Suncus murinus insectivora,inhabiting islands and the continent based on mitochondrial DNA types

Cleavage patterns of mitochondrial DNA (mtDNA) by restriction endonucleases were examined in musk shrews collected at six trapping sites on two Japanese and two Indonesian islands, on Sri Lanka, situated close to the Indian subcontinent, and on the mainland of East Bengal in Bangladesh. No variation of mtDNAs was found among the Japanese and Indonesian shrews, despite their geographical isolation by the sea. In contrast, at least six mtDNA types were present in the Sri Lanka and the Bangladesh populations (three types for each), and these two populations seemed to be differentiated to the extent, which could be compared to the mice-intersubspecific differences. These populations were also differentiated from the Japanese-Indonesian type. Furthermore, a similar level of differentiation was also estimated between two mtDNA types within these respective populations. This feral species might be considered unique because of its high emigration rate caused by human movements and its high rate of subspecific hybridization.     

Diaspora identification and long-distance nationalism among Tamil migrants of diverse state origins in the UK

Accounts of Tamil long-distance nationalism have focused on Sri Lankan Tamil migrants. But the UK is also home to Tamils of non-Sri Lankan state origins. While these migrants may be nominally incorporated into a ‘Tamil diaspora’, they are seldom present in scholarly accounts. Framed by Werbner's (2002) conception of diasporas as ‘aesthetic’ and ‘moral’ communities, this article explores whether engagement with a Tamil diaspora and long-distance nationalism is expressed by Tamil migrants of diverse state origins. While migrants identify with an aesthetic community, ‘membership’ of the moral community is contested between those who hold direct experience of suffering as central to belonging, and those who imagine the boundaries of belonging more fluidly – based upon primordial understandings of essential ethnicity and a narrative of Tamil ‘victimhood’ that incorporates experiences of being Tamil in Sri Lanka, India and in other sites, despite obvious differences in these experiences.     

Rapid Fishery Assessment by Market Survey (RFAMS) – An Improved Rapid-Assessment Approach to Characterising Fish Landings in Developing Countries

The complex multi-gear, multi-species tropical fisheries in developing countries are poorly understood and characterising the landings from these fisheries is often impossible using conventional approaches. A rapid assessment method for characterising landings at fish markets, using an index of abundance and estimated weight within taxonomic groups, is described. This approach was developed for contexts where there are no detailed data collection protocols, and where consistent data collection across a wide range of fisheries types and geographic areas is required, regardless of the size of the site and scale of the landings. This methodology, which was demonstrated at seven fish landing sites/fish markets in southern Indonesia between July 2008 and January 2011, provides a rapid assessment of the abundance and diversity in the wild catch over a wide variety of taxonomic groups. The approach has wider application for species-rich fisheries in developing countries where there is an urgent need for better data collection protocols, monitoring future changes in market demographics, and evaluating health of fisheries.     

Distribution of seagrasses along the Indian coast

Seagrass environments, from the main coast of India, Lakshadweep and Andaman Islands, were surveyed for seagrass and marine algal composition. Extensive seagrass meadows and the maximum number of species (seven genera and 12 species) occurred along the Tamil Nadu coast. Seagrasses were observed from intertidal to subtidal regions down to 8 m depth. Thalassia hemprichii (Ehrenberg) Aschers. and Cymodocea serrulata (R. Brown) Aschers. & Magnus were the dominant seagrasses in the subtidal zones. Halophila beccarii Aschers. was restricted to the intertidal mudflats in association with mangroves. The rich growth of seagrasses along the Tamil Nadu coast and Lakshadweep can be attributed mainly to high salinity, clarity of the water and sandy substratum. One hundred species of marine algae were recorded from the seagrass environments of India.     

In Retrospect the Assumption of Sustainability for Atlantic Fisheries has Proved an Illusion

Fishery landings data series from 1970 to 2002 for the Northeast (FAO Area 27) and Northwest Atlantic (Area 21) with 73 and 42 species or species groups respectively, were mapped onto single charts as a diagnostic of the overall state of fisheries in these two regions, and could be appreciated simultaneously for the entire exploited suite of species as a series of contiguous bar charts. Charts were compared with that for a similar data set of 42 species or species groups from the Mediterranean and Black Seas (FAO Area 37). A “traffic light convention” partitioned the range of landings by species over the period into four equal intervals; coloured respectively red, yellow, green and blue between zero and the highest annual landing of the species. This allowed a model-free display of changes in the timing of species’ landings at the overall ecosystem level, as represented by the important commercial resources in the three areas. The year T₅₀ by which 50% of species landings had been harvested over the period, was considered a comparable measure of the response of individual species to exploitation. For a significant proportion of groundfish and pelagic fishes, the time to reach T₅₀ occurred early in the Atlantic time series. The hypothesis was tested that this measure of the depletion schedule is related to some aspect of species biology, as judged by data from the FISHBASE database. Except for commercial invertebrates where landings peaked late in the Northwest Atlantic time series, no significant regression was found between T₅₀ values per species and any biological characteristic of the species of finfish tested, suggesting that scheduling may reflect overcapacity and targeting by fisheries and/or regime changes. A decline in peak landings proceeded sequentially over time for the large proportion of all finfish species in the North Atlantic following a broadly similar trajectory. Possible exceptions were deeper water species where fisheries began later, suggesting that “fishing down the bathymetry” has occurred. A more synchronous “pulse” of high landings occurred in the Mediterranean and Black Seas in the mid-late 1980s, which was postulated as due to an increase in system productivity. Although regime changes and quota management cannot be excluded as partly responsible for the persistent low landings late in many time series, the main conclusion is that for all three areas, the effects of fishing overshadow those resulting from differing biological characteristics, habit, or species interactions. Although quota control may in part be responsible for low landings of some species late in the time series, the fishery management regimes that applied during 1970–2002 cannot be considered sustainable. This was confirmed by comparative analysis fitting a variety of models to the raw landing data. Of the mathematical models considered, the Hubbert curve, first used to predict the trajectory of extraction of non-renewable petroleum resources globally over time, best fitted the largest proportion of species time series. This seems to confirm that a hypothesis of harvest sustainability cannot be supported by the landing data.     

Mapping and analysis of the physical vulnerability of coastal Tamil Nadu

Abstract

This is an integrated study to classify Tamil Nadu Coast in terms of its vulnerability to coastal processes. It is accomplished through estimating Coastal Vulnerability Index (CVI) for the entire stretch of the said coast using weighted averages of six parameters, viz., geomorphology, shoreline changes, coastal slope, and relative sea level rise, mean significant wave height and mean tidal range. Thus, CVI evaluates the state of the coast in terms of level of risk hovering on it as and when it is affected by oceanic hazards. The target of this study is to evaluate the vulnerability status of coastal stretches of 35 taluks of Tamil Nadu. Twenty one percent of the coastal stretch is under very high vulnerability level. Following this is 36% stretch under high vulnerability state. Another 34% coastal stretch is in moderate setting. Low vulnerability state prevails about 6%. Further, it is learnt that there are only 2% of Tamil Nadu coastal region coming under the least vulnerable category. The study revealed the very high vulnerability of Nagapattinam coastal region. The present study may also help create awareness among people about marine natural hazards such as coastal erosion, inundation, loss of life and their properties.     

Observations on the mass migration of Bridled Terns Sterna anaethetus off the coast of Colombo

A mass mieration of Bridled Terns Sterna anaethetus has been observed periodically off the south western coast of Sri Lanka during the past several years (Hoffmann 1975, Phillips 1978) and it is now evident that the phenomenon is an annual occurrence A preliminary study was initiated in 1981 (De silva 1982) and the results encouraged the continuation of observations until late October 1984 Only those aspects of migration which were visible from land are dealt with here     

Stunting in Oreochromis mossambicus (Peters) (Pisces, Cichlidae): An evaluation of past and recent data from Sri Lankan reservoir populations

Tilapiine fish are known to become stunted under different environmental conditions. Of the tilapia, Oreochromis mossambicus (Peters), once considered to be the aquatic chicken, is now treated as a nuisance species in some countries because of its tendency to stunt easily. O. mossambicus is the mainstay of the commercial gillnet fishery in existence in the multitude of reservoirs in Sri Lanka for over 35 years. Published and new evidence on O. mossambicus population traits are presented with a view to evaluating whether the populations in Sri Lankan reservoirs are stunted or not. The main lines of evidence considered are the mean size at maturity (Lm), the proportion of individuals below 20 cm total length in the commercial landings, and growth performance of the individual reservoir populations. Statistically valid inter-relationships exist between the mean length at maturity and the proportion of undersized individuals (below 20 cm) in the landings, and the ratio of the reservoir catchment or watershed area to surface area. Evidence on Lm indicate that there is a tendency for O. mossambicus populations to stunt, however, evidence on growth and mean landing size do not indicate stunting.     

Alleles at plasma alpha-amylase locus(Amy-1) of the house musk shrew(Suncus murinus): frequency distribution and new variants in laboratory lines and local Asian populations

Among nine laboratory shrew lines originating from the Japanese islands (Nag, Tok, TKU, Ize, Tr and OKI lines), West Java (Bog), Bangladesh (BAN) and Sri Lanka (SRI), Nag, Tr and Bog were fixed with Amy-1b and SRI with Amy-1a. The remaining lines were still highly polymorphic with the two alleles. A new electrophoretic band C was found in the BAN line and concluded to be expressed by a codominant allele, Amy-1c, which was carried by a single heterozygous female from among eleven wild shrews of the original breeding stock. In most local populations of the Asian shrews surveyed, Amy-1b was more common than Amy-1a. The Sri Lanka population was clearly distinguishable from the others, being nearly fixed with Amy-1a. The C band was found in eleven (one homozygous) of 86 wild shrews caught in Bangladesh. Of a total of 234 wild shrews collected from four Japanese and two Indonesian islands, Bangladesh, and Sri Lanka, only two showed different AMY-bands from AMY-A, -B and -C, and such bands were not found in the laboratory-bred shrews examined.     

Zooplankton composition and diversity in western Bay of Bengal

The biomass of zooplankton ranged from 1 – 90 ml/100 m³in the western Bay of Bengal from off Sri Lanka to south ofCalcutta in June 1978. The coastal belt between Madras and Visakhapatnamwhere upwdling is known to occur during the season showed higherstanding stock. Copepoda formed the dominant group followedby Decapod a and Chaetognatha. Species composition of variousgroups and their distribution is discussed. A general inverserelationship between biomass and species diversity was the trend.Diversity was higher in the oceanic realm.     

Visual detection of filaria-specific IgG4 in urine using red-colored high density latex beads

The use of urine for the immunodiagnosis of lymphatic filariasis has a definite advantage: the sample collection is not invasive and thus well accepted by people. Urine-based ELISA to detect filaria-specific IgG4 has been used successfully. However, ELISA requires equipment such as a microplate reader, which is often not available in most endemic areas. We have developed a new visual immunodiagnosis that detects urinary IgG4 using red-colored latex beads (bead test). The sensitivity was 87.2% when ICT antigen test positive people were regarded as the standard (136/156), and the specificity was 97.2% with the non-endemic people in Japan and Bangladesh, and the urine ELISA negatives in Sri Lanka (1264/1300). In a prevalence study, the bead test could detect filarial infection more effectively than ICT test among young children in Sri Lanka, indicating the usefulness of the visual test in epidemiological studies.     

Notes on the occurrence of the tropical eel Anguilla bicolor bicolor in Peninsular Malaysia, Malaysia

Previous studies indicated that a tropical freshwater eel Anguilla bicolor bicolor occurs in Africa, India, Sri Lanka, Bangladesh, Myanmar, Indonesia and Australia, but an intensive survey has indicated an extended distribution range for the species into Peninsular Malaysia. Thus, A. b. bicolor is a native subspecies of Malaysia.     

Framing disputes and organizational legitimation: UK-based Sri Lankan Tamil diaspora groups' use of the ‘genocide’ frame since 2009

The ending of the war in Sri Lanka in 2009 led to significant changes in the political strategies pursued by Sri Lankan Tamil diaspora groups in the UK. One contentious feature of these groups' campaigns has been their use of the ‘genocide’ frame to describe the actions of the Sri Lankan state, which has been predominantly viewed either as a signal of these groups' strategic naivety or as a coded expression of a wider nationalist agenda. In this article I argue that its growing use in the post-war period is more complex and is best understood in relation to these organizations' strategies of legitimation. Deploying the genocide frame has served two key functions: to demonstrate groups' responsiveness to popular demands, and to challenge dominant international approaches to post-war Sri Lanka. Together these functions served to bolster groups' legitimacy in an environment characterized by political change and high levels of inter-organizational competition.