“The economic importance of mangroves in Pakistan largely comes from the fishery resource that they harbor. An estimated 80% of the fish caught in coastal waters spend at least part of their life cycle as fry in the mangrove creeks, or depend on the food web within the mangrove ecosystem. Shrimp fishery is the major fish export of mangroves, accounting for 68% of the $100 million of the foreign exchange the country earns from fisheries exports. The mangrove swamps of the Sindh coastal zone are extensive, covering 243,000 hectares (ha) compared with 7,400 ha along the Balochistan coast. The zone also has large areas of bare mud flat. The system is intersected by large and small creeks that allow tidal water to move into and out of the area during the twice-daily ebb and flow of the tides. The mangrove swamps are made up of several indigenous species of trees that are adapted to live in brackish water or sea water. The main species in the area is the black mangrove Avicennia marina, which has aerial roots growing up out of the mud. The swamps also have less common species of mangrove tree, the main one on the Sindh coast being the red mangrove Rhizophora mucronata. Both species of mangrove tree are important sediment and soil stabilizers. Several species of marine seaweed also grow in mangrove swamps, often as algal mats on the surface of the mud.”