Mangrove ecosystem and shrimp aquaculture in SW Bangladesh

Published: 17th October 2012 12:55Last Updated: 17th October 2012 11:55
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Coastal livelihoods in SW Bangladesh are largely dependent on its natural resources of mangrove forest (timber, wood fuel, honey, fish and other aquatic species) agriculture and marine fisheries. Following construction of the coastal embankment and other development investment there have been drastic environmental changes. Loss of life in major flooding events have been reduced. However, this has not led to overall improvements in the living condition of the majority of people.

Our aim in WD-NACE has been to develop and test participatory methods for gathering the data to populate a conceptual framework to understand decision-making in coastal resources. In Bangladesh the issue of the emergence of shrimp farming, associated land-use changes (where it comes into competition with paddy farming and encroaches upon mangrove areas), ecological changes and social contestation has been identified as an ongoing challenge for decision-making and policy formulation (linkage between ecosystem services (ES) and poverty alleviation (PA)).

The question of how to mitigate negative impacts of shrimp farming on other kinds of livelihood and obtain equitable benefits and alleviate poverty, should be understood as an intersection of individual, community and national-level decision-making. It must also be understood in the context of increasing pressure on resources, global market changes, climate change-related hazards.

Bangladesh in the media

This section provides links to articles that highlight some of the issues being investigated in WD-NACE SW Bangladesh case study. There is huge attention to major flood events, environmental change and livelihood adaptation in the region. This is a collection of informative articles that could be of interest to weADAPT readers.

Here is a good update on what is happening in the SW coast of Bangladesh and what partners (BCAS, CEGIS and Shushilan) are doing to help: New Internationalist article

Two newspaper articles on the 2nd anniversary of cyclone AILA in the Sundarban area:

Part of the road from Khulna to Munshiganj had been damaged by flooding. Background: crab and shrimp farming.

The following sections provide further background to the situation in SW Bangladesh and outline some of the approaches taken to understand the 'whole decision network'. Most of the following work is 'in preparation' for publication; therefore further information will be added soon.


Resource mapping

Participants engaged in WD-NACE workshops were asked to discuss the state of coastal and marine ecosystems in the Shatkhira district, as a representative case study for Bangladesh. The state of ecosystems was discussed at all levels (national to local), but the trends and drivers of change were discussed in more depth at the local-level workshops. Drivers of change were explored in terms of human actions that contributed to a change in the state of resources and ecosystems.

Since the early 1990s, shrimp farming has surpassed marine shrimp harvesting due to rapid wild shrimp stock decline. The main driver behind the growth of shrimp cultivation is commercial, export-oriented business, which in two decades has displaced labour from other local agricultural activities. Although shrimp farming continues to grow occupying a larger area over time (currently 90% of the area), productivity has decreased in about 30% due to virus attacks and an increase of salinity in water after the cyclone AILA affected the embankment and illegal construction of gates started in the 1990s by influential people at that time. In 2009, a new regulation was introduced by the Bangladesh Water Development Board to close all illegal sluice gates and limit the boundaries of farming to reduce production loss. The former decision had positive effects on salinity control although people started circulating saline water for shrimp farming over pipelines. The latter decision had positive impacts on people and on the shrimp resource. To complement and diversify shrimp farming, crab cultivation and collection has expanded rapidly in the area since the early 2000s supported by an increase in international demand accompanied with low production costs.

Resource map produced from the local level workshop in Satkhira

Also see this placemark on the resource trends in Munshigonj

Social Network Mapping

Social network mapping (SNM) was used to explore relationships between the different actors that shape the governance of coastal ecosystems in Bangladesh. The method was developed based on the NetMap Toolbox developed by Schiffer (2007, 2010) and adapted to be integrated with steps of the ARDI methodology developed by Etienne et al. (2006). Participatory network mapping was conducted through workshops at the national-l, sub-national-l (i.e. district and regional workshops) and local-levels, involving relevant organizations at each level.

During each workshop, participants were divided in groups with similar or shared interests. As a result, three groups were formed in each workshop: public institutions and authorities, the private sector, and the non-governmental organizations and civil society. In the case of local workshops, the local realities required a different distribution: shrimp businessmen, fishermen, labour workers, and farmers and women.

Groups discussed problematic issues around coastal and marine ecosystems, focusing on the Satkhira district to provide a common reference point. They were asked: “What actors play a role (or should play a role) in the management of coastal and marine ecosystems to improve human well-being and alleviate poverty?”

Once presented with the question above, participants in each group were requested to list all the organizations (i.e. network actors or nodes) that (directly or indirectly) manage the coastal and marine ecosystems in the area. This list of actors was used to develop the social network maps in each working group. They show three types of ties or flows between the actors (i.e. network edges), namely: information/ knowledge flows, capacity support flows, and financial flows. Examples are shown below:

Sustainability analysis

Sustainability analysis was carried out at the local, community level in each of the three study regions (Satkhira, Bagerhat and Khulna) as well as at wider scales of decision-making, regional and national, in order to understand how sustainability is framed at different levels and in different locations, using Q-Methodology. The study focused on the three topics of: the mangrove forest ecosystem, coastal waters (including fisheries and flood control) and shrimp-farming activities. Participants were asked their views about the challenges for management and law-making, and about the impacts of different livelihoods/activities or other drivers such as climate change.

Statistical techniques were used to construct groups that shared similar views, followed by qualitative interpretation of the similarities and differences among group responses, to build an aggregated picture of different framings of sustainability and possible tensions where beliefs (and interests) differ. For example, identification of one group oriented towards forest conservation, one group supportive of shrimp farming, and one group with a disapproval of local governance, could help to explain why certain policies have or have not been implemented in an area.

Social-ecological system modelling

Modelling approaches included ecological system modelling, agent-based modelling and multi-criteria analysis decision modelling. A prototype agent-based social simulation model to explore the shrimp-paddy interactions and farm livelihoods was developed through participatory work in the region. The model illustrates the following ideas:

  1. Shrimp farming is more profitable than paddy (especially for large land managers that can acheive economies of scale; whereas for small farmers it carries some risks)
  2. River water access is necessary for shrimp, and therefore it is likely that farmers near river decide to do shrimp farming
  3. Leeching of salt occurs from shrimp area to paddy
  4. Build-up of salt deposits may exceed what is rinsed out during monsoon rains
  5. High salinity is detrimental to paddy health, and therefore a high % of shrimpfarms leads to overall saline condition, influencing other farmers to decide for shrimp production 

Shrimp farming therefore has a reinforcing character and it is easy to understand how a shrimp farming regime may emerge. A screenshot of the simulation model is shown below.

Initialisation of model showing farms, village, mangrove, river and their physical connections. Farm labels indicate access to river flows.


This work was funded by the Ecosystem Services for Poverty Alleviation programme (ESPA) as project number NE/I00288X/1. ESPA is funded by the Department for International Development (DFID), the Economic and Social Research Council (ESRC) and the Natural Environment Research Council (NERC), as part of the UK’s Living with Environmental Change Programme (LWEC).


Further resources

WD-NACE case study of the South Kenyan coast

The below links provide further information about the WD-NACE case study in Kenya, which focused on decision-making in artisinal capture fisheries.