Facultad de Ciencias Biólogicas

Rocky shores are areas of high diversity and productivity providing goods and services. Since humans are altering nature at an unprecedented rate, producing shifts in important parameters for life such as temperature, habitat availability, water quality, among others, it is expected that species will respond by changing their natural distributions and/or abundances. To understand how species will respond to such changes, it is necessary to learn the processes that determine these patterns. The South American Research Group on Coastal Ecosystems was established to assess marine diversity and biomass along both coasts of South America through an international collaboration. The main goals of SARCE are to: (1) Test hypotheses about latitudinal gradients and patterns of local and regional biodiversity, (2) Identify the relationship between biodiversity and ecosystem functioning, (3) Assess the effect of environmental gradients and anthropogenic stressors, (4) Carry out capacity building and training activities aimed to solve environmental problems for the benefit of society. The SARCE network has sampled the coasts of nine countries around South America with a standardized protocol in more than 150 sites (2010-2014), ranging from 11º North to 55º South. This chapter provides a description of the biodiversity of the sites sampled by SARCE, along with a review of the uses and services that these ecosystems provide to human populations and the main threats and impacts these uses have caused.

(1) Two species of free-ranging polychaetes, Pseudonereis gallapagensis and Halosydna johnsoni, coexist in the mussel bed habitat of a rocky shore in Peru, South America. There are two mussel beds: the Semimytilus algosus bed which extends widely between the low ...

Abstract. Mussel beds in the intertidal of subtropical South America are known to har-bour a large number of invertebrates, particularly polychaetes. This paper presents a quantitative analysis of the patterns of spatial overlap and coexistence in an assemblage of polychaetes ...

The mussel Semimytilus algosus (Gould) often dominates the space on exposed rocky shores of subtropical South America. Dynamics of space occupancy was investigated in a rocky intertidal habitat in central Peru. A series of colonization experiments and ...

Foraging behaviour in the South American sunstar Heliaster helianthus (Lamarck) was investigated quantitatively on a subtropical rocky shore in central Peru. H. helianthus feeds mainly on two mussel species, Semimytilus algosus (Gould) and Perumytilus purpuratus (Lamarck). A sequence of foraging behaviour was described and observations were made of the timing of attacks on mussel beds by sun-stars. Although H. helianthus is capable of foraging out of water, an unusual trait for asteroids, the timing of such foraging appears to be well adjusted to avoid the risk of prolonged heat and desiccation. Foraging activity began 4 h 52 min before high tide and 3 h 19 min after high tide, with a mode between 2 h 30 min and 2 h before high tide. Fifty-two percent of all foraging activity began between 3 h 30 min and 2 h before high tide, while only 12.4% began after high tide. This suggests that H. helianthus mainly relies upon changes in the rate of tidal increase as a cue to begin foraging. F...

We have analysed molt frequency and reproductive behaviour of G. grapsus in relation to mutilation frequency and cannibalism observed during mating. Observations and surveys were carried out between December 1990 and December 2001, on a 200 m stretch rocky shore in the south of Ancon Bay, Lima, Peru. Population of G. grapsus was organized in groups of variable numbers around