Subrata Sarker

Habitat modelling of juvenile Hilsa Tenualosa ilisha (Clupeiformes) in the coastal ecosystem of the northern Bay of Bengal, Bangladesh

Hilsa shad Tenualosa ilisha comprises the largest and most valuable single fishery of Bangladesh. This study was conducted to identify suitable habitats for Hilsa juvenile in the northern Bay of Bengal along the coast of Bangladesh using Geographical Information Systems (GIS) based Multi-Criteria Evaluation (MCE) of water temperature, dissolved oxygen, pH, salinity, turbidity, current, depth and rainfall. Landsat imagery and 8 thematic layers were analyzed with ENVI and GIS capabilities, and developed as a series of GIS models to identify and prioritize the appropriate habitats for Hilsa juvenile. The study covered 29.484 km2 water body and revealed that 56% (16.388 km2) is the most suitable, 21% (6.054 km2) is moderately suitable and 24% (7.042 km2) is not suitable which was consistent with field verification. The assemblage of marinebrackish-freshwater ecosystems with favourable ecological parameters and rainfall patterns are very much important for supporting juvenile Hilsa in the study area. The results are useful for habitat-specific sanctuary development as the efficient conservation may lead to higher production of adult Hilsa and increase the economic benefit to the fishers.

Freshwater Fish Diversity at Greater Noakhali, Bangladesh

ABStRAct This study assessed the spatial-temporal diversity of fish at greater Noakhali, an aquatic ecosystem that supports the most diverse fish communities in Bangladesh. Fish samples were collected from eight locations from July 2010 to June 2011 and diversity analyzed using PAST software. Findings showed that greater Noakhali is the habitat for 128 fish species. For the whole sampling area, the Shannon diversity index, evenness, Margalef richness and dominance index values were 4.501, 0.889, 15.763 and 0.012, respectively. Oreochromis mossambicus, Mastacembelus armatus and Tenualosa toli were the major contributory species in temporal terms and Tenualosa ilisha, Somileptes gongota and Mystus vittatus in spatial terms.

New species of leaf fish Nandus meni (Perciformes: Nandidae) from Noakhali, Bangladesh

Nandus meni sp. nov. is described from the Meghna deltaic region in Noakhali, Bangladesh, after a detailed morphological examination and careful comparisons with other geographically proximate congeners. N. meni can be readily diagnosed by having the following combination of characters: total length 114.1–142.4 mm, standard length (SL) 94.1–117.3 mm, body depth at anus 29.0–32.9% of SL, head length (HL) 39.6–42.2% of SL, a dark spot on the caudal peduncle, a concave ventral portion of the body, gill arch V-shape, greenish body colour, 9–11 pectoral fin rays, snout length 24.5–33.1% of HL and eyes diameter 18.1–20.4% of HL. The new species N. meni differs from other congeners in having greenish body colour, smaller eyes, a concave ventral body, a V-shaped gill arch and a dark spot on the caudal peduncle.

Production in Small Scale Aquaculture Farm: A Success Story from Bangladesh

Small scale aquaculture plays an important role in rural poverty elevation. Present study was carried out at Ramgonj Upazila (sub-district) of Bangladesh and aimed to fathom out the story of small scale aquaculture in Bangladesh with its problems, solution and economics. Data were collected from personal interview and participatory observation. Small scale aquaculture in Bangladesh plays a significant role in meeting the homestead fish protein demand and serves as an important livelihood option. Rural people of Bangladesh convert house hold pond to culture farm and faced problem which includes fund, disease, feed crisis, bloom and others. Therefore, government involvement and providing extension service can mitigate these problems.