La almeja navaja Tagelus plebeius y su participación en mecanismos ecológicos de comunidades intermareales mediante la producción de valvas

JORGE LUIS CEFERINO GUTIERREZ; VALERO, J. L.

Reserva de Biósfera Mar Chiquita: Características físicas y ecológicas

Editorial Martin

Lugar: Mar del Plata; Año: 2001; p. 121 - 128

The stout razor clam Tagelus plebeius is an important component of the benthic fauna of several Southwestern Atlantic estuarine environments. In the present study we summarize the current state of knowledge about this species, focusing on the palaeoenvironmental and the ecological consequences of their shell deposits. A horizon with T. plebeius shells showing articulated and life-position valves occurs in Holocene tidal flat sediments of regional estuarine environments. Although there are a variety of hypotheses about their origin, continuous and cumulative predation by the American oystercatcher Haematopus palliatus seems to be the most likely mechanism for their formation. Erosion in recent years has resulted in the surfacing of shells covering large intertidal areas. The surfacing of these shells implies important changes in the intertidal habitat and the benthic community structure. Moreover, the surfacing of Holocene shells can also be promoted by the sediment overturning caused by clam harvesting with similar ecological consequences. This indicates that indirect ecological consequences of past oystercatcher predation remains hidden for a long period of time and are expressed once processes such as erosion or clam harvesting occur.