Biotopos marinos intermareales y submareales (Crucero Cimar 16 fiordos) desde el Estrecho de Magallanes al Canal Beagle

Abstract

During the Crucero CIMAR 16 Fiordo which extended between the Estrecho de Magallanes and the Canal Beagle (53º1116'S; 73º24 06'W-55º09'03 92''S, 68º08'27 9''W), intertidal and subtidal sampling were made in 14 stations. These samples were taken by hand and with apnea dives, arranged in transects that were perpendicular to the coastal lines, with a south east orientation.

In these stations the coastal biotopes classifi cation used and established in the Crucero CIMAR 15 was applied. A total of 10 coastal marine biotopes were determined, arranged in the following three groups:

1) biotopes with a strong freshwater infl uence by icecaps melting and rains having infl uence on extended beaches, without rocky slopes, and with a small diversity, with Porphyra spp. in conspicuous fl at rocks, and with salinity which varies between 1 and 20‰;

2) rocky biotopes with greater slopes, with a clear tide infl uence and they have red, brown and green algae, and their salinity varies between 24 and 28‰;

3) shallow subtidal biotopes, between 1 and 16,4 m of depth, characterized by the existence of brown algae, Macrocystis pyrifera mainly, associated with mollusks, crustaceans, polychaetes, and echinoderms and having a salinitiy which varies between 32 and 35‰.

Coincidences with the biotopes described from the Parque Nacional Laguna San Rafael, estero Elefantes, archipiélago de los Chonos, and three other biotopes mentioned for the canal Trinidad and canal Smyth, located to the north of the Estrecho de Magallanes, were observed.