Currently, the buffaloes are freely raised with no restricting mechanism in its locomotion, such as fences or wood bridges.

This uncontrolled management of the animals, especially the buffalo herds, causes severe environmental imbalance, such as trenching the river, changing the Flexal river runoff, enlarging a mud puddle and muddying the ground nearby, forest destruction in areas where animals are kept and the increase in the silting of rivers.

The wetland region is comprised by floodplains and several ponds that retain water. These ponds are maintained by the rain and communicate with the main river by creeks and natural channels. The water regime, even far from the ocean, also includes the tidal waters, given the force in which the freshwater returns to the river several miles inland.

The lakes are governed by the daily rise and fall of the waters, and with a greater volume and intensity at the rise of the water, which characterizes the Amazon winter.

The siltation caused by the herd in these lakes has increased water runoff channels, besides the natural creeks. These channels, called ditches by the river dwellers, are systematically draining the lakes and changing the water’s rise and fall regime in the area. According to the local inhabitants, there is a significant decrease in the volume of water of these lakes and the flood plains. As a consequence, there is a dramatic change in the local ecosystem, as a decline in numbers of fish and a vegetation change with the invasion of non-native plants, which does not replace their native plants eating habits.

The erosion in ditches, river banks, canals, and levees caused by the buffaloes adversely affect some fish species and reduce the growth of algae. There is a significant difficulty for the survival of native vegetation due to the water cycle change, because there is no submerged soil during most months of the year.

The lack of an adequate management also contributes to the increasing occurrence of invasive plants such as the “naffatvel” (Ipomoea fistulosa), which was brought from Rio de Janeiro as an ornamental plant; however it’s been spread throughout a large region. Its effects on the ecosystem and on the buffalo feeding have not yet been clearly studied though. It has hallucinogenic properties and it is addictive, there were even reports of death of the buffalo herd; the river dwellers state that is a toxic plant, although they do not know about its lethal dose.

The survival of this plant does not occur in the water, however with the opening of ditches that intensify the water runoff, there is an increase of the non-submerged areas, collaborating with the appearance of the cotton during the dry season, causing a proliferation of the specie in detriment of the canarara grass.