The distributional and abundance patterns of macroorganisms from Intertidal rocky shore of Traiguén Island, (45°S. 73° W) Estero Elefantes, Aisen Region, Chile

Abstract

The distribution and abundance patterns of benthic organisms from the rocky intertidal shore of Isla Traiguén, Estero Elefantes (45° S, 73° W) are described quantitatively. Data were taken mainly from cover and direct count (density) of the individuals along two lines of about 28 m in perpendicular transects to the tide line of on the intertidal zone. The results allow us to point out the following ditributional patterns for the studied rocky communities. On the high inteitidal: transect 1 exhibits dominants species being the red algae Porphyra sp. and the mollusk Diloma nigerrima-, in transect 2, dominants are the mollusks Diloma nigerrima and Nodilittorina araucana and the crustaceans Cyclograpsus sp. and Cancer sp. On the low intertidal rocky shore of the transect 1, dominate the red algae Mazzaella laminarioides and the invertebrates Jehlius cirratus, Petrolisthes sp., Nacella mageUamca and Tegula atra. On transect 2 were found Jehlius cirratus, Mazaella laminarioides and Tegula atra as the dominant species also, as well as Nothogenia fastigiata, Sarcothalia crispata and Siphonaria lessoni. These quantitatives results are the first ones on intertidal marine organism communities from the rocky shore environments with low slope in the Chilean southern channels of the Region Aisen.