PARENT SESSION
Organized Oral Session 43: Complex consequences of spatial subsidies to food webs
Organizer(s): JM Kraus and WB Anderson
Thursday, August 11, 8:00 AM - 11:30 AM, Meeting Room 511 B, Level 5, Palais des congrès de Montréal
Who eats crustacea and insects? Consumers' behavior on the sea-land interface of the temperate Chilean coast.
Farina, Jose*,1, Sabat, Pablo*,2, 1 1Center for Advanced Studies in Ecology and Biodiversity (CASEB), Santiago, RM, Chile2 Departamiento de Ciencias Ecológicas, Facultad de Ciencias, Santiago, RM, Chile
ABSTRACT- The movement of materials and consumers between ecosystems is a common process in nature. If two ecosystems differ greatly in their levels of productivity, nutrients will move from the more productive to the less productive system and consumers should move from the less to the more productive habitat. However, when these habitats are in different ecosystems some physiological and biological barriers for the movement of consumers across the ecosystem boundarycould exist. In northern Chile, in the confluence between one of the most productive marine ecosystems of the world (the Humboldt current) with one of the less productive terrestrial ecosystems of the world (the Atacama desert), we has been exploring the activities of terrestrial reptiles (lizards) and birds (passerines) that visits rocky intertidal habitats Our results shows that those consumers eat mostly marine preys (invertebrates an algae) but that the importance of marine food on their diet decreases geographically. Following the increase on terrestrial productivity, in the northern areas there is a major dependence on marine preys while the ones in southern most areas include a major proportion of terrestrial prey. We explain this pattern in reference to the geographical changes on the productivity imbalance between terrestrial and marine ecosystem and with the geographical changes on environmental variables (such us temperature and cloudiness).
Key words: Microlophus, Cinclodes, Atacama Desert, Trophic ecology