Recent advances in our knowledge of the biology and conservation of mahseers

Mahseers (Tor khudree), at one time considered to be of single species, are now represented by 6 valid species distributed all over India. Studies on their food habits, ecology of spawning grounds, eggs, larval development and especially methods of artificial propagation have advanced in recent years. Transport of eggs of Tor khudree by air in moist cotton has been possible for easy distribution. Breeding of T. khudree not only by hypophysation, but even without it in small ponds by manipulation of flow of water, exercise and feed has also been possible. Fry and fingerlings of T. khudree are being distributed to many of the states in the country to help conserve the species.

Diversity of wetland fish and its impact on the income of fishermen community of Assam.

A survey was conducted in 3000 fishermen households surrounding 54 wetlands (Beels) of Assam. The fish diversity of the wetlands has been decreasing during the last few years due to some extrinsic and intrinsic factors. The total number of fish species recorded so far during the present study is 67 belonging to 21 families. Cyprinidae is the most dominant family represented by major group species (8), intermediate group species (3) and minor group species (12) of high commercial value. Among these three groups, the diversity of fish species is higher in the minor group fish. The present paper deals with the economic condition of the fishermen who mainly fish in the wetlands. The economic condition of the fishermen community is found very poor. The income of fishermen varies from Rs. 4.478 to Rs.7,484 per annum. A regression analysis shows that the income of fishermen is not dependent alone on the fish production but it is exclusively dependent on the value of the fish catch. All the three groups (in terms of value) have significant influence at 10.00% confidence level. But analysis of β shows that the intermediate fish group exhibits the highest influence on the variation of the fishermen income followed by minor and major group respectively.

Scale structure, age and growth in the freshwater carp, Labeo calbasu (Pisces/Cyprinidae) from Harike wetland, India

Age structure and growth profile based on the scale studies of 468 specimens ranging from 17-62 cm total length of Labeo calbasu (Hamilton) from Harike wetland (30°13'N, 75°12'E), Punjab, India have been described, the present study showed better growth in terms of two important growth parameters namely index of species average size and population weight-growth intensity. Two distinct phases in its life history have been described that indicates the optimum exploitation of this species from this water body. Harvestable size is found to be fish of 34 cm total length. The detailed structural elaboration of scale (normal, regenerated, lateral line) has also been done using scanning electron microscopy (SEM).

Some problems and issues of sustainable management of mangrove ecosystems of Tamil Nadu, India

Mangrove, a tidal wetland, is a good example of complex land and water system whose resource attributes is neither fully understood from an ecological perspective nor valued comprehensively in economic terms. With increased ecological and social perception of the functions of wetlands, the utility and relative values will increase. The perception, however, varies from society to society. It must be recognized that mangrove forests differ greatly in local conditions and in their ability to produce a wide variety of economic products. What may be highly productive strategy for one country may have little meaning to its neighbor. Therefore, it becomes essential that from among diversity of potential uses of the mangrove environment, specific uses will have to be decided, and management plan developed on site, or area specific basis. It is therefore necessary to arrive at a balance between the views of the ecologists and economists on the management of mangroves. Biological conservation should encompass resource management in the sense that integrity of the biological and physical attributes of the resource base should be sustained and man-induced management practices should not alter an ecosystem to the extent that biological production is eliminated. Sustained yield management for food, fiber and fuel would serve to sustain local fisheries while generating new economic enterprises. This requires the recognition of mangrove environment as a resource with economic value, and managed according to local conditions and national priorities.

Feasibility study of biofuel production from freshwater fern, Azolla sp in Anzali Wetland

Production of bioethanol through acidic and enzymatic hydrolysis of aquatic Azolla sp., as a new source of bio-mass, has been performed, as a means to control increasing growth and reducing undesirable effects of this plant in Anzali lagoon. After sampling, drying and crushing, Azolla was hydrolyzed, using diluted acid and enzyme. Diluted acid hydrolysis was done using both autoclave and a high-pressure system (Batch Synth® Microwave synthesizer). The effects of temperature and time (in autoclave) and concentration of acid (in both) were compared. Cellubrix®, a ommercial cellulase source, was used for enzymatic hydrolysis process. The amounts of reducing sugars, glucose and furfural, released from hydrolyzate, were measured. To produce alcohol, Sacchromyces cerevisiae (to ferment sixcarbon sugars), Zygowilliopsis californica and Pichia stipitis (to ferment five-carbon and sixcarbon sugars) were used. Maximum amounts of glucose (4.83% w/w) and reducing sugars (14.15% w/w) were obtained using acid hydrolysis in autoclave. In the microwave oven, maximum glucose (5.04% w/w) and reducing sugars (13.27 w/w) were obtained at 180 and 200 °C, respectively. Under these conditions, maximum produced furfural was 1.54 g/L. The difference between amounts of furfural obtained from acid hydrolysis of Azolla in microwave oven compared to autoclave was statistically significant. Amounts of alcohol produced and its yields were 3.99 g/L and 33.13% for S. cerevisiae in 48 hours, 3.73 g/L and 30.45% for Pichia stipites in 48 hours, and 3.73 g/L and 30.45% for Z. californica in 24 hours after inoculation, respectively, with significant differences. Statistical comparison of results showed significant differences (P<0.05) in glucose production, at different conditions. Amounts of reducing sugars and glucose increased after optimization of levels of acid, time, and temperature. The overall optimum released sugar and glucose were obtained with 1.67% (w/v) acid using autoclave. Higher temperatures in microwave oven caused a significant increase (P<0.05) in furfural. Furfural severely inhibits fermentation. Hence, regarding the issues of energy consumption and time, amounts of inhibiting substances and sugar production, autoclave is found to be superior to the high temperature and pressure, generated in microwave oven, for hydrolyzing Azolla. Furthermore, given the amounts of Azolla in Anzali lagoon, it may be recommendable to use this plant as a biomass resource.

Report of the training course on seagrass conservation and monitoring in Myanmar Coastal Zone, Mawlamyine University, Myanmar, 26 April-3 May, 2013

A training course on seagrass conservation and monitoring was conducted at Mawlamyine University and Ngapali Beach government department and Non-Government Organizations (NGO) trainees.

Report of the national stakeholder consultation workshop on Sri Lanka NPOA for the conservation and management of sharks, 03 December, 2013, Colombo, Sri Lanka

The objectives of the workshop were to; ensure shark catches were sustainable; assess threats to shark populations; identify vulnerable shark stocks; protect biodiversity; improve consultation involving stakeholders; minimize waste a discards and facilitate monitoring and landings data.

Survey of shark fisheries and preparation of a National Plan of Action (NPOA) for conservation and management of shark resources in Bangladesh

The report presents; terms of reference; work progress; surveys of shark fishers and traders; shark biodiversity survey; and a National Plan of Action (NPOA) for conservation and management of shark resources in Bangladesh.