Dataset Information

Catch composition and life history characteristics of sharks and rays (Elasmobranchii) landed in the Andaman and Nicobar Islands, India.

ABSTRACT: Detailed information on shark and ray fisheries in the Andaman and Nicobar Islands, India are limited, including information on the diversity and biological characteristics of these species. We carried out fish landing surveys in South Andamans from January 2017 to May 2018, a comprehensive and cost-effective way to fill this data gap. We sampled 5,742 individuals representing 57 shark and ray species landed from six types of fishing gears. Of the 36 species of sharks and 21 species of rays landed, six species of sharks (Loxodon macrorhinus, Carcharhinus amblyrhynchos, Sphyrna lewini, C. albimarginatus, C. brevipinna, and Paragaleus randalli) comprised 83.35% of shark landings, while three species of rays (Pateobatis jenkinsii, Himantura leoparda and H. tutul) comprised 48.82% of ray landings, suggesting a species dominance in the catch or fishing region. We provide insights into the biology of species with extensions in maximum size for seven shark species. Additionally, we document an increase in the known ray diversity for the islands and for India with three previously unreported ray species. We found that amongst sharks, mature individuals of small-bodied species (63.48% males of total landings of species less than 1.5 m total length when mature) and immature individuals of larger species (84.79% males of total landings of species larger than 1.5 m total length when mature) were mostly landed; whereas for rays, mature individuals were predominantly landed (80.71% males of total landings) likely reflecting differences in habitat preferences along life-history stages across species and fishing gear. The largest size range in sharks was recorded in landings from pelagic longlines and gillnets. Further, the study emphasizes the overlap between critical habitats and fishing grounds, where immature sharks and gravid females were landed in large quantities which might be unsustainable in the long-term. Landings were female-biased in C. amblyrhynchos, S. lewini and P. jenkinsii, and male-biased in L. macrorhinus and H. leoparda, indicating either spatio-temporal or gear-specific sexual segregation in these species. Understanding seasonal and biological variability in the shark and ray landings over a longer study period across different fisheries will inform future conservation and fishery management measures for these species in the Andaman and Nicobar Islands.

SUBMITTER: Tyabji Z

PROVIDER: S-EPMC7595311 | biostudies-literature | 2020

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

Catch composition and life history characteristics of sharks and rays (Elasmobranchii) landed in the Andaman and Nicobar Islands, India.

Tyabji Zoya Z Wagh Tanmay T Patankar Vardhan V Jabado Rima W RW Sutaria Dipani D

PloS one 20201029 10

Detailed information on shark and ray fisheries in the Andaman and Nicobar Islands, India are limited, including information on the diversity and biological characteristics of these species. We carried out fish landing surveys in South Andamans from January 2017 to May 2018, a comprehensive and cost-effective way to fill this data gap. We sampled 5,742 individuals representing 57 shark and ray species landed from six types of fishing gears. Of the 36 species of sharks and 21 species of rays land ...[more]

PMID: 33119595

Similar Datasets

Project description:BackgroundPools of salt water and puddles created by giant waves from the sea due to the tsunami that occurred on 26th December 2004 would facilitate increased breeding of brackish water malaria vector, Anopheles sundaicus. Land uplifts in North Andaman and subsidence in South Andaman have been reported and subsidence may lead to environmental disturbances and vector proliferation. This warrants a situation analysis and vector surveillance in the tsunami hit areas endemic for malaria transmitted by brackish water mosquito, An. sundaicus to predict the risk of outbreak.MethodsAn extensive survey was carried out in the tsunami-affected areas in Andaman district of the Andaman and Nicobar Islands, India to assess the extent of breeding of malaria vectors in the habitats created by seawater flooding. Types of habitats in relation to source of seawater inundation and frequency were identified. The salinity of the water samples and the mosquito species present in the larval samples collected from these habitats were recorded. The malaria situation in the area was also analysed.ResultsSouth Andaman, covering Port Blair and Ferrargunj sub districts, is still under the recurring phenomenon of seawater intrusion either directly from the sea or through a network of creeks. Both daily cycles of high tides and periodical spring tides continue to cause flooding. Low-lying paddy fields and fallow land, with a salinity ranging from 3,000 to 42,505 ppm, were found to support profuse breeding of An. sundaicus, the local malaria vector, and Anopheles subpictus, a vector implicated elsewhere. This area is endemic for both vivax and falciparum malaria. Malaria slide positivity rate has started increasing during post-tsunami period, which can be considered as an indication of risk of malaria outbreak.ConclusionPaddy fields and fallow land with freshwater, hitherto not considered as potential sites for An. sundaicus, are now major breeding sites due to saline water. Consequently, there is a risk of vector abundance with enhanced malaria transmission potential, due to the vastness of these tsunami-created breeding grounds and likelihood of them becoming permanent due to continued flooding in view of land subsidence. The close proximity of the houses and paucity of cattle may lead to a higher degree of man/vector contact causing a threat of malaria outbreak in this densely populated area. Measures to prevent the possible outbreak of malaria in this tsunami-affected area are discussed.

Project description:Dragon fruit (Hylocereus spp.), an important tropical fruit belonging to the family Cactaceae, is rich in essential nutrients such as vitamins, minerals, complex carbohydrates, dietary fibres and antioxidants. This study aims to distinguish three dragon fruit species well adapted to Andaman and Nicobar Island through morphological (34 quantitative and 26 qualitative traits), biochemical (5 traits) and molecular (14 ISSR primers) characterization. Morphological characterization revealed that presence of considerable amount of genetic variations among them especially for fruit characters viz., colour of peel and pulp. Cladode characters such as number of spines (3-5), length of areoles (mm) as 1-4, margin ribs of cladode (convex or concave) and its waxiness (weak or strong white waxy or light waxy) could be used for identification of three Hylocereus spp. under present study. Highest co-efficient of variation (%) obtained for pulp weight (88.7), whereas, lowest in distance of anthers belowstigma (3.3). Fruit and pulp weight (g) ranged from 26.5-419.3 and 10.3-258.8 with mean value of 204.8 and 125.3, respectively. Comparatively, high phenol (71.3-161.3) and flavonoid (26.6-508.2) content observed in peels than pulp (32.5-130.0 and 45.0-258.2) of fruit indicating higher antioxidant potential. Highest total carotenoids (µg 100 g-1), β-carotene (µg 100 g-1) and xanthophyll (µg g-1) content obtained in pulp on DGF3 (33.8), DGF4 (55.9) and DGF3 (32.7), whereas, in peel on DGF2 (24.3), DGF4 (18.5) and DGF2 (24.1), respectively. DPPH-based scavenging activity (%) revealed higher scavenging activity of peels (55.6-81.2) than pulp (36.0-75.3) extracts. Comparatively, ABTS-based scavenging activity (%) was found more than DPPH-based one. Sixteen ISSR primers screened, 14 were produced 178 reproducible amplified bands. Number of amplified bands varied from 5 in UBC887 to 19 in UBC811 with an average of 12.71 bands per primer. Range of polymorphic bands and % polymorphism observed were 1-13 and 20.0-92.8, respectively. The polymorphic information content value of ISSR marker ranged from 0.42 (UBC895) to 0.91 (UBC 856). Cluster analysis distinguished three different Hylocereus species on the basis of geographic origin and pulp colour by forming separate groups and two genotypes each showed 52% (DGF1 and DGF3) and 76% (DGF2 and DGF4) genetic similarity. Key traits identified for distinguishing three different Hylocereus species were: Pulp/ peel colour of fruits, number of spines and length of areoles in cladode. Genotypes with high carotenoid and xanthophylls content (DGF4 and DGF2) identified under present study may be of industrial importance for development of nutraceutical products to meet out the vitamin-A deficiency among humans in tropical regions needed future focus.

Project description:BACKGROUND:Andaman and Nicobar Islands situated in the eastern part of Bay of Bengal are one of the distinguished biodiversity hotspot. Even though number of studies carried out on the marine flora and fauna, the studies on actinobacteria from Andaman and Nicobar Islands are meager. The aim of the present study was to screen the actinobacteria for their characterization and identify the potential sources for industrial and pharmaceutical byproducts. RESULTS:A total of 26 actinobacterial strains were isolated from the marine sediments collected from various sites of Port Blair Bay where no collection has been characterized previously. Isolates were categorized under the genera: Saccharopolyspora, Streptomyces, Nocardiopsis, Streptoverticillium, Microtetraspora, Actinopolyspora, Actinokineospora and Dactylosporangium. Majority of the isolates were found to produce industrially important enzymes such as amylase, protease, gelatinase, lipase, DNase, cellulase, urease and phosphatase, and also exhibited substantial antibacterial activity against human pathogens. 77% of isolates exhibited significant hemolytic activity. Among 26 isolates, three strains (NIOT-VKKMA02, NIOT-VKKMA22 and NIOT-VKKMA26) were found to generate appreciable extent of surfactant, amylase, cellulase and protease enzyme. NIOT-VKKMA02 produced surfactant using kerosene as carbon source and emulsified upto E(24)-63.6%. Moreover, NIOT-VKKMA02, NIOT-VKKMA22 and NIOT-VKKMA26 synthesized 13.27 U/ml, 9.85 U/ml and 8.03 U/ml amylase; 7.75 U/ml, 5.01 U/ml and 2.08 U/ml of cellulase and 11.34 U/ml, 6.89 U/ml and 3.51 U/ml of protease enzyme, respectively. CONCLUSIONS:High diversity of marine actinobacteria was isolated and characterized in this work including undescribed species and species not previously reported from emerald Andaman and Nicobar Islands, including Streptomyces griseus, Streptomyces venezuelae and Saccharopolyspora salina. The enhanced salt, pH and temperature tolerance of the actinobacterial isolates along with their capacity to secrete commercially valuable primary and secondary metabolites emerges as an attractive feature of these organisms. These results are reported for the first time from these emerald Islands and expand the scope to functionally characterize novel marine actinobacteria and their metabolites for the potential novel molecules of commercial interest.

Dataset Information

Catch composition and life history characteristics of sharks and rays (Elasmobranchii) landed in the Andaman and Nicobar Islands, India.

Publications

Catch composition and life history characteristics of sharks and rays (Elasmobranchii) landed in the Andaman and Nicobar Islands, India.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets