The Impact of Co-management on the Sundarbans Fisheries: Evidence from Sharankhola, Bagerhat, Bangladesh

The study was conducted in the Sarankhola, Bagerhat during the period from August to October, 2012 to determine the impact of co-management on the Sundarbans fisheries. At present only one co-management organization is working in the study area. The co-management organization is performing various activities to make fisheries resources of the Sarankhola, Sundarbans sustainable. Co-management initiatives included: awareness raising, alternate income generation, eco-tourism and efforts towards social mobilization. The key regulatory measures and steps of co-management included: Limited Boat License Certificate (BLC), protection of parents hilsa and protection of jatka. Integrated Resources Management Plans (IRMP) was formulated by the Forest Department for sustainable fisheries management of the Sundarbans. IRMP made two major guidelines: One was fisheries resource conservation measures and the other was fisheries improvement measures. Fisheries improvement measures in the study area were weak. The production data revealed that fish production in the Sundarbans is declining in the recent years. It is an important breeding and nursery ground of a wide range of estuarine, offshore and marine fishes and shrimps. Fisheries resource is being degraded due to lack of proper co-management of the resource. So, effective co-management activity is essential for sustainable fisheries resources conservation-management in the Sundarbans. Keywords: Co-management, Integrated Resources Management Plans (IRMP) DOI: 10.7176/JBAH/10-2-07 Publication date: January 31st 202

Protein-sparing ability of carbohydrates from different sources in diets for fry of stinging catfish Heteropneustes fossilis

The experiments were carried out to evaluate the protein-sparing effect in Heteropneustes fossilis fry (0.751 ± 0.01 g) fed for 90 days with six isocaloric diets containing 45, 40 or 35% of casein-protein and 25, 30 or 35% of glucose/dextrin, combined properly as the work purpose. The highest weight gain was recorded in fry fed with 35% dextrin and 35% crude protein level. Interestingly, the value of SGR (2.950±0.017) and PER (1.793±0.03) were significantly (p<0.05) increased with reducing protein level from 45 to 35% and with increasing carbohydrate level from 25% to 35%, respectively. However, the poorest growth was recorded in the fry fed with glucose containing diets than dextrin-containing diets. Protein deposition was significantly (p<0.05) lower in fry fed with the glucose diets at the protein level of 45% than those fed with 40 or 35%, indicating that H. fossilis utilize dextrin easily than glucose. Increase of dextrin content from 35 to 45% did not reduce (p<0.05) the weight gain, even reducing the dietary protein from 45 to 35%. This fact suggests that carbohydrate spare protein by using dextrin as energy source

Protein-Sparing Ability of Carbohydrates from Different Sources in Diets for Fry of Stinging Catfish Heteropneustes fossilis (Keupayaan Jimat Protein Karbohidrat daripada Sumber Berbeza dalam Diet untuk Anak Keli Stinging Heteropneustes fossilis)

ABSTRACT The experiments were carried out to evaluate the protein-sparing effect in Heteropneustes fossilis fry (0.751 ± 0.01 g) fed for 90 days with six isocaloric diets containing 45, 40 or 35% of casein-protein and 25, 30 or 35% of glucose/dextrin, combine

RAST JEDNOSPOLNE I NILSKE TILAPIJE MJEŠOVITOG SPOLA U UVJETIMA PREZIMLJAVANJA NA SJEVEROISTOKU BANGLADEŠA

The study was conducted to assess the over-wintering growth performance of mixed-sex and mono-sex male tilapia, Oreochromis niloticus. The experiment was carried out with two treatments each with three replicates for a period of 6 months from October, 2012 to March, 2013 in the Field Laboratory Complex, Bangladesh Agricultural University. In the first treatment (T1), mixed-sex tilapia was stocked in 3 ponds with a mean initial weight of 4.80±0.18 g. In the second treatment (T2), mono-sex male tilapia was stocked in another 3 ponds with a mean initial weight of 4.81±0.20 g. Fish were fed at the rate of 6% of fish body weight at the beginning of the experiments then the feeding rates were gradually reduced to 2% for the third month and finally increased to 3% for rest of the period. Water parameters in terms of temperature, dissolved oxygen, pH, transparency, alkalinity, ammonia and nitrite were within the range of fish farming. After 6 months of culture period mono-sex male tilapia attained a significantly (P0.05) difference of food conversion ratio and survival rate (%) values between the treatments. The benefit-cost ratio was calculated as 1.17 and 1.43 for mixed-sex and mono-sex male tilapia, respectively. The results suggested that it is possible to successfully culture tilapia during the winter period in Bangladesh and the culture of mono-sex tilapia is more profitable due to its higher growth rate.Cilj ovog istraživanja bila je procjena rasta nilske tilapije mješovitog i muškog spola, Oreochromis niloticus, u uvjetima prezimljavanja. Eksperiment se sastojao od dva tretmana s tri ponavljanja u razdoblju od 6 mjeseci, od listopada 2012. do ožujka 2013. godine na vanjskim bazenima (Field Laboratory Complex) Poljoprivrednog sveučilišta u Bangladešu. U prvom tretmanu (T1) je tilapija mješovitog spola prosječne početne težine 4,80 ± 0,18 g bila smještena u 3 ribnjaka. U drugom tretmanu (T2), tilapija muškog spola prosječne početne težine 4.81 ± 0.20 g bila je smještena također u 3 ribnjaka. Na početku eksperimenta ribe su bile hranjene po stopi od 6% od njihove ukupne tjelesne mase, a potom su stope hranjenja postepeno smanjivane do 2% u trećem mjesecu te na kraju povećane na 3% u preostalom vremenu. Parametri vode poput temperature, otopljenog kisika, pH, prozirnosti, alkaliniteta, amonijaka i nitrita bili su u skladu s vrijednostima pogodnima za uzgoj ribe. Nakon 6 mjeseci uzgoja, tilapija muškog spola dosegla je značajno veću prosječnu konačnu težinu (P 0,05) i postotku stope preživljavanja (%) između tretmana. Rezultati su pokazali mogućnost uspješne kultivacije tilapije u zimskom periodu u Bangladešu, s time da je uzgoj jednospolne tilapije isplativiji zbog njezine veće stope rasta

Use of Urban Open-waterbody to Enhance Fish Production through Cage Culture

The purpose of the experiment was to examine the effect of cage fish culture on the growth and production performances of Shing (Heteropneustes fossilis), Pabda (Ompok pabda) and Gulsha (Mystus cavasius). The stocking density for each fish species was 100 fish/m3. Cages with Shing, Pabda and Gulsha were treated as T1, T2 and T3, respectively. Fishes were fed with artificial diet at the rate of 5-10% of body weight. The experiment was carried out in cages in the Beel from June to November 2019. The study revealed that water quality parameters were not varied significantly (p &gt; 0.05) among the treatments. The growth and production performance were significantly (p &lt; 0.05) higher for Pabda cage culture followed by Gulsha and Shing cultures in cages. Therefore, the total net return (BDT 17,028) and benefit cost ratio (2.48) were significantly (p &lt; 0.05) higher for Pabda fish considering cost benefit analysis. It was concluded that, among the three different fish species, high-valued Pabda is highly acceptable candidate for cage farming in Belai Beel area and cage farming in urban open waterbodies is a promising approach to increase the total fish production to improve the social and economic status of fish farmers. [J Bangladesh Agril Univ 2023; 21(1.000): 75-85

Outwelling of nutrients into the Pasur River estuary from the Sundarbans mangrove creeks

The Pasur River estuary (PRE), the largest estuary in the Sundarbans mangrove area, provides vital fishery resources and supports millions of livelihoods in the southwestern coastal region of Bangladesh. This study focused on the tidal and run-off effects on the outwelling of nutrients from the Sundarbans mangrove creeks to the PRE. Spatial and temporal variations of nutrient and chlorophyll-a concentrations were assessed by water sampling at 11 stations in the study area from January to December 2019. Dissolved inorganic nutrients and chlorophyll-a were analyzed by standard methods using a spectrophotometer. In the tidal mangrove creeks, dissolved inorganic nitrogen, phosphate, and silica concentrations were significantly higher (p 0.05) different between the two tidal levels. This study showed that the mangrove creeks formed an important link in transporting nutrients from the mangrove forest to the estuary