The Cojimiles estuary lies on the border of the provinces of Esmeraldas and Manabi at the northern end of Ecuador’s mainland coast. The watershed of the estuary reaches into the adjacent cordillera, the majority of which was placed within the Machi-Chindul Ecological Reserve in 1996.

Cojimiles, Ecuador

Until the coastal highway was completed in 2000, this 64km2 estuary was in one of the most isolated coastal regions. Maps drawn from aerial photographs taken in 1976 show an estuary surrounded by 15,770ha of mangrove wetlands. According to the inventory of the Military Cartographic Institute (CLIRSEN) by 1999 only 1,863ha of mangroves remained and 13,907ha of shrimp ponds had been constructed along the borders of the estuary previously occupied by mangroves and extending in places both into the estuary itself and the adjoining freshwater wetlands and pockets of low lying land. The estuary is connected to the ocean at its northern end and until recently was seasonally connected to the ocean by a channel at the southern end near Pedernales. As a result of deforestation in the watershed and shrimp pond construction sedimentation in the estuary has increased and islands in the mouth of the estuary have become larger. This, combined with reduced freshwater inflow has reduced water circulation and causes the inner estuary to behave at times as a reverse estuary where salinities are highest. Large expanses of the estuary are now only navigable at high tide. In 2001 there was a major fish kill in the mid and inner estuary. Today formerly abundant shellfish (Anadaria spp.) are sparse or absent except near the estuary’s mouth at the northern end.

The hilly eastern shore of the estuary and the upper watershed was until recently one of the remaining tracts of rainforest internationally recognized as containing exceptionally high biodiversity. In recent decades immigration into the Reserve by subsistence farmers and commercial loggers has increased and deforestation is rapid. This has pushed the indigenous inhabitants further inland. It is widely believed that deforestation of the watershed is the primary cause of reduced freshwater inflows from the seven streams and small rivers that flow into the estuary. According to residents all seven used to flow all year. Currently all but one are seasonal. The western border of the estuary is a low peninsula that is the site of the town of Cojimies – formerly the principle settlement and port – and, at its southern end, Pedernales. Today Chamanga, in the mid section of the eastern shore, is a major commercial center.

A detailed timeline for the Cojimies region reveals an accelerating processes of change in the social-ecological system. While this region was well populated and appeared wealthy and well organized when Pizarro landed in a town a few kilometers to the south, the invasion by Spanish conquistadores left the region sparsely populated and blanketed in dense forests. In 1920 Cojimies town was an isolated out-port and a small and primitive settlement had begun to form on the shores of the estuary in Chamanga. The contemporary process of development saw its first brief expression when Esmeraldas province was the center of banana production in Ecuador. The fertile flat lands in the Cojimies region were made into small, locally owned, banana plantations that flourished for the decade that began in 1945. This brief boom ended when growers to the south in El Oro corner the market for the Gross Michel cultivar that was better suited to international markets. In the 1950s and ‘60s there was an international market for the bark of mangrove trees that was processed as a source of tannin for use in leather making industries. This supported an artisinal industry that felled all the largest mangrove trees - some of which yielded as much as 5000 lbs of bark. During all this period a sparse population lived primarily a subsistence lifestyle that benefited from the abundant fish and shellfish, fertile soils and abundant rainfall.

The first shrimp farms were constructed in the inner estuary in 1974 by local farmers with local capital. By 2000, 15,000 hectares of ponds had been constructed and were managed by approximately 800 owners. The need to export their shrimp created mechanisms for exporting the abundant fish that could be readily caught in the estuary. This produced a period of abundant and easy wealth that continued until the white spot disease decimated shrimp populations in 2000. During this period local fishermen could harvest several hundred lbs of wild shrimp in a single night and marketable finfish were large and abundant. Earning of US$200 per week for a fisherman operating from a canoe were common.

The white spot epidemic closed down the packing house and idled two thirds of the ponds. By that time the populations of wild shellfish and finfish were much reduced. The completion of the surfaced coastal road that same year, the fish kill and high unemployment added to pressures in the Reserve. The coastal highway made illegal logging easier and the rate of deforestation increased.

By 2006 the Ecuadorian farmed shrimp industry had recovered. The value of the shrimp, that are currently harvested at a smaller size, is less than previously. Growers in the inner estuary have been plagued by off-flavor of their product and there is growing concern over the quality of the water in the estuary and the reduced inflows of freshwater from streams and rivers. Today a large proportion of the population lives in poverty, unemployment is high and artisinal fishing and agriculture produce a meager income. A large proportion of the mature men have migrated leaving a population dominated by women, children and old people. Highway access to the region is attracting beach tourism to Pedernales and adventure tourism to the northern end of the region where remnants of the rainforest are still present and surfing is said to be of the very best.