The animal portion of plncton, zoo-plncton, is fed of the microseaweed of fitoplncton and organic substance in suspension. Larvae of shrimps, crabs and siris filter the water and remove microseaweed and organic substance. Small fish filtradores, as manjuba, also is fed of this rich organic broth. From the microseaweed, if it establishes an alimentary teia complex. How much to the fauna, some species of crabs are distinguished, forming enormous deep populations in the slimy ones. In the submerged trunks, some animals filtradores, such as the oysters, are fed of suspended particles in the water.
The crabs in its majority are active in the tide low, while the clams feed themselves during the high tide. A great variety of fish penetrates in the manguezais in the high tide, many of them constitutes the supply fishing boat of coastal waters depends on the alimentary sources of the manguezal, at least in the young phase. Diverse species of birds eaters of fish and marine invertebrates nidificam in the trees of the manguezal. They are fed especially in the tide low, when deep the slimy ones are displayed. The fen is also the place where many clams, fish and crustaceans find ideal conditions for reproduction, nursery, criadouro and shelter.
The roots of the fen function as filters in the retention of the sediments and constitute important genetic bank for the recovery of degraded areas. Its vegetation serves to fix lands hindering the erosion and also functions as choke of the energy of the high tides, helping to protect is to stabilize the coastal band, as cites the article FORESTS OF TIDE, published in the nathional magazine Geographic, in 01.02.07' ' The outcries for the conservation had soon obtained more important attention in the mat of tsunami2 of 2004, in the ocean indicate. In the places where the manguezais were unbroken, them they had acted as natural break-sea, had wasted the energy of the waves, had minimized damages to the properties and perhaps they have saved lives.