The Mekong Basin has one of the world's largest and most productive inland fisheries. An estimated two million tonnes of fish are landed a year, in addition to almost 500,000 tonnes of other aquatic animals. Aquaculture yields about two million tonnes of fish a year. Hence, the lower Mekong basin yields about 4.5 million tonnes of fish and aquatic products annually. The total economic value of the fishery is between US$3.9 and US$7 billion a year. Wild capture fisheries alone have been valued at US$2 billion a year. This value increases considerably when the multiplier effect is included, but estimates vary widely.