SciELO - Scientific Electronic Library Online

vol.73 issue3Factors affecting the circular distribution of the leafless mistletoe Tristerix aphyllus (Loranthaceae) on the cactus Echinopsis chilensisGeographic variability in thermal tolerance and water economy of the intertidal gastropod Nodilittorina peruviana. (Gastropoda: Littorinidae, Lamarck, 1822) author indexsubject indexarticles search
Home Pagealphabetic serial listing  

Services on Demand




Related links


Revista chilena de historia natural

Print version ISSN 0716-078X


PACHECO, CRISTIAN J.  and  CASTILLA, JUAN C.. Trophic ecology of the oystercatchers Haematopus palliatus pitanay (Murphy 1925) and Haematopus ater (Vieillot et Oudart 1825) on beds of the tunicate Pyura praeputialis (Heller 1878) in the Bay of Antofagasta, Chile. Rev. chil. hist. nat. [online]. 2000, vol.73, n.3, pp.533-541. ISSN 0716-078X.

At Antofagasta, northern Chile, two oystercatcher species coexist: the white oystercatcher, Haematopus palliatus pitanay and the black oystercatcher H. ater. Both species forage on an intertidal system where the middle fringe is dominated by the tunicate Pyura praeputialis (= Pyura stolonifera bradleyi; Kott 1997). According to the literature, differences in the morphology of their bills (length and width) segregate the foraging roles of white and black oystercatchers when the birds coexist in the same habitat. H. palliatus pitanay is best adapted for capturing soft bodied preys, while black oystercatcher H. ater attack "hard" preys (i.e. preys with calcareous shells). We consider here that the tunicate P. praeputialis as a soft bodied prey because the tunic, composed of tunicine, is soft and pliable. We compare ecological aspects between the two oystercatchers species in Antofagasta, such as: (a) abundance of oystercatchers and other coastal birds preying on P. praeputialis, (b) the spatial distribution of the oystercatchers in the Pyura bed during foraging periods, (c) Pyura size preferences of oystercatchers, (d) handling time, (e) consumption rate and (f) preference of other invertebrates prey items distinct from Pyura. The results show that H. palliatus pitanay attacks more frequently Pyura than H. ater, and that H. ater attacks more frequently "hard" preys such as: limpets, snails, mussels and sea urchins.

Keywords : oystercatchers; tunicate; Haematopus; Pyura, trophic ecology; rocky intertidal; Chile.

        · abstract in Spanish     · text in Spanish     · Spanish ( pdf )


Creative Commons License All the contents of this journal, except where otherwise noted, is licensed under a Creative Commons Attribution License