Patrones de zonación, comportamiento e interacciones de poliquetos en diferentes ambientes intermareales

GABRIELA PALOMO; MAURICIO ESCAPA; DIEGO NAVARRO

Reserva de Biosfera Mar Chiquita: Caracteristicas fisicas, biologicas y ecologicas.

Editorial Martin

Lugar: Mar del Plata; Año: 2001; p. 93 - 99

In Mar Chiquita coastal lagoon seven polychaetes species lives on the soft-bottom, occuping different areas. Information about biology and ecology of these species is very limited. Most of the information is about Laeonereis acuta. This polychaete is more abundant on the mid intertidal zone, and have small densities on the high and low intertidal level. This distribution pattern could be due to physical factors and biological interactions like predation. In crab beds areas, densities decreased in comparison with areas without crabs. Bioturbation produced by crabs could affect the survival of benthic infauna. Vertical movements during the tidal cycle are less important inside crab beds. Laeonereis acuta had better body condition inside crab beds, probably because of sediment quality. Feeding and burrowing activity of L. acuta decreased the bedload sediment transport, putting on surface small particles with higher content of organic matter, that leads to the stabilization of sediments. Several species affect the distribution and abundance of Laeonereis acuta. Piscivourous seabirds increased nutrients on sediments, and abundances of L. acuta have a significant increase in seabirds resting areas. Predators also affect them, waders and ants fed on this species as a main item, modifying the abundance particularly in areas without crabs. Laeonereis acuta. This polychaete is more abundant on the mid intertidal zone, and have small densities on the high and low intertidal level. This distribution pattern could be due to physical factors and biological interactions like predation. In crab beds areas, densities decreased in comparison with areas without crabs. Bioturbation produced by crabs could affect the survival of benthic infauna. Vertical movements during the tidal cycle are less important inside crab beds. Laeonereis acuta had better body condition inside crab beds, probably because of sediment quality. Feeding and burrowing activity of L. acuta decreased the bedload sediment transport, putting on surface small particles with higher content of organic matter, that leads to the stabilization of sediments. Several species affect the distribution and abundance of Laeonereis acuta. Piscivourous seabirds increased nutrients on sediments, and abundances of L. acuta have a significant increase in seabirds resting areas. Predators also affect them, waders and ants fed on this species as a main item, modifying the abundance particularly in areas without crabs.