Agricultural Research Management Information System

Home
Research Summary
Search
About Us
- ARMIS
- Brochure
Contact Us
Report
User Request
Data Input
Help
- Operation Manual
  - PDF
  - Video
- Program Area & Commodity
We have reached 37600 number of research entries at this moment.

- Logout

Research Detail

Home
Research
Detail

The Chalan Beel in Bangladesh: Habitat and Biodiversity Degradation, and Implications for Future Management

Mostafa A. R. Hossain
Faculty of Fisheries, Bangladesh Agricultural University, Mymensingh-2202, Bangladesh

Paul G. Olin
Sea Grant Extension Program, University of California, Davis Cooperative Extension, 133 Aviation Blvd., Suite 109, Santa Rosa, California 95403, USA

M. Abdul Wahab
Faculty of Fisheries, Bangladesh Agricultural University, Mymensingh-2202, Bangladesh

M. Ekram Azim
Department of Physical and Environmental Sciences, University of Toronto, 1265 Military Trail, Toronto, Ontario M1C 1A4, Canada

M. Abu Sayeed
Faculty of Fisheries, Bangladesh Agricultural University, Mymensingh-2202, Bangladesh

M. Nahiduzzaman
Faculty of Fisheries, Bangladesh Agricultural University, Mymensingh-2202, Bangladesh

Abstract/ Executive Summary:

This study provides an overview of the current resources and fisheries status of the Chalan beel, and identifies the scope of opportunities to evolve existing fisheries management strategies, focusing on fish biodiversity conservation. Chalan beel is the largest, most important watershed in the North Central Bangladesh, and covers an area of about 375 km² during the monsoon season. The watershed serves about 5 million people, predominantly through fisheries and agricultural activities. Although considerably degraded over time, Chalan beel still supports a diverse ichthyofauna of major importance to the local economy and people’s livelihoods. The Chalan beel area incorporates 21 rivers and 93 smaller seasonal beels of varying size. Most of the rivers and beels are at risk of partial or total degradation, as a result of agricultural encroachment, siltation and other anthropogenic activities. During the study, ≈ 83% of the rivers, and 68% of the beels in the lean season, shrunk to 0–5% of their maximum (monsoon) water-spread area during the dry season (i.e. critical levels for survival of many fish species). A fish catch survey was carried out in the main fishing season (July to December) over two successive years in the three most important catchment areas; namely, the Gumani, Baral and Katagang Rivers. A total of 72 sampling episodes yielded 9818 individuals, representing 114 fish species. The most abundant fish species during the 2-year study period were punti (Puntius sophore and Puntius ticto), followed by chanda (Chanda nama and Parambassis ranga), chapila (Gudusia chapra) and tengra (Mystus vittatus). The study results indicate at least 19 fish species once considered abundant can now be classified as threatened, with a possibility of local extinction. The mean fish catch was 2.08 ± 0.49 kg, and 1.29 ± 0.32 kg per hour per person, by suti jal (set bag net – the most common gear used in the beel) in 2005 and 2006, respectively, with a significant (P < 0.05) variation among catches in months and years at all three sample sites. In 2005–2006, the annual fish production in Chalan beel was 12 217 tonnes, being less than half of the production observed in 1982. The stakeholders identified several major causes they thought were directly responsible for the continued decrease in fish production and biodiversity of the beel area. Several management strategies were suggested by the same stakeholders, and the findings are discussed in the context of overall developments in the Chalan beel fisheries related to habitat and biodiversity management.

Keywords: Chalan beel, Fish biodiversity, Gear efficiency, Management strategies.

Location: Natore, Pabna, Sirajgonj

Start Date: 00-00-2005

End Date: 00-00-2006

Program Area: Conservation and Biodiversity

Commodity: Aquatic animal

Objectives:

To know the current status of habitat and fish biodiversity in Chalan beel, and
To explores management options that emerged through dialogue with local stakeholders.

Methodology:

Field works were undertaken in each of the 10 upazilas over which the Chalan beel spread in 2005 and 2006 – ?Singra, Gurudaspur, Boraigram, Chatmohar, Bhangura, Faridpur, Shahjadpur, Ullapara, Tarash, and Raigonj, in three districts (Natore, Pabna, Sirajgonj). Data were collected from (i) interviews and focus group discussions with primary and secondary stakeholders; (ii) direct sampling; and (iii) secondary literature. Semistructured and structured questionnaires were developed, pretested and adapted prior to the survey proper. Key issues addressed included; (i) present status of the various habitats under Chalan beel; (ii) fish biodiversity; and (iii) causes of habitat and biodiversity degradation and their possible mitigation measures. The stakeholders: A total of 185 stakeholders, including fishers, fish farmers, upazila fisheries officers, local leaders, school teachers and housewives, participated in this study. Ten focus group discussions were conducted in 10 upazilas of Chalan beel area. The characteristics of the stakeholder, including the nature of any primary dependency on the beel. Fish catch sampling: Three rivers are known to be the main sources of the capture fishery in the Chalan beel: (i) Gumani river at Gurudaspur Upazila (Natore district); (ii) Baral River at Chatmohar Upazila (Pabna District); and (iii) Katagang River at Tarash Upazila (Sirajgonj District). These three rivers were selected for sampling. Set bag nets (Suti jal) were deployed to capture all types and sizes of fish, with minimum selectivity, in order to assess species composition. Sampling was performed twice a month during the main fishing season (October to November) in 2005 and 2006, with each sample performed in triplicate. When possible, fish were identified, counted, weighed and then released onsite. Otherwise, they were preserved in 10% formalin in plastic jars for laboratory assessment. The collected fish were identified. In order to estimate fishing gear efficiencies, in addition to the set bag net, the fish sampling also was conducted with four other commonly used gears, including (i) seine net; (ii) gill net; (iii) cast net and (iv) fish traps. Each of these five gears was sampled in triplicate at the same sample sites described above, although only monthly during July to December in 2005 and 2006. The results were triangulated against other available secondary data sources, namely, the Department of Fisheries reports, although non-government organization reports, scientific journal articles and other published reports and materials also were consulted. Statistical analysis: In order to estimate the interannual catch changes of the most abundant species, the catch coefficient of variation within each year (CVw = 100 Sm/Xm, where Xm and Sm are the mean and standard deviation of monthly abundance, respectively), and among years (CVa = 100 Sa/Xa, where Xa and Sa are mean and standard deviation of annual abundance, respectively), were calculated. Frequency counts for the most abundant species were subjected to analyses of variance (ANOVA) in order to assess potential differences between the three sample sites, 2 years and fishing months. Factors were tested with the general linear model (GLM) for analysis of variance (ANOVA) at a 0.05 significance level. Statistical analyses were performed using the SPSS (windows version 11.5) software package.

Source of Information: Lakes & Reservoirs: Research and Management 2009; 14: 3–19

Article Link (Online Journal):

Funding Source:

Total Budget (Tk.) :

Achievement/Findings:

The stakeholders identified several major causes they thought were directly responsible for the continued decrease in fish production and biodiversity of the beel area. Several management strategies were suggested by the same stakeholders, and the findings are discussed in the context of overall developments in the Chalan beel fisheries related to habitat and biodiversity management.

Knowledge Management: Journal