Functional composition of Polychaeta group in Paita Bay and the adjacent shelf (5°S), Perú. February 2003 to October 2008

Abstract

Yupanqui W, Enríquez E, Quipúzcoa L, Marquina R, Velazco F, Paredes C, Gutiérrez D. 2011. Functional composition of
Polychaeta group in Paita Bay and the adjacent shelf (5°S), Perú. February 2003 to October 2008. Bol Inst Mar Perú 26(1-2): 65-
73. The aim of this study was to determine the bathymetric and temporal variation of the functional composition of the
group Polychaeta trophic guilds. Samples of macrobenthos and oceanographic information were collected in three stations
located in the bay (BH, 35 m), inner shelf (PI, 65 m) and outer shelf (PE, 117 m), from February 2003 to October 2008. The
results indicate that seasonal variability are subject to larger scale changes such as increased primary production in spring
and summer, allowing an increase in the BH of the SDF during spring, due to the accumulation of organic matter reaching
phytoplankton in the bottom. Also, the decrease of the surface depositivorous (SDF) and suspension feeders (SF) increased
in summer in the bay (BH) and inner platform (IP), can be explained due to increment discharge of terrigenous particles
of plant origin that physically affecting the substrate. Meanwhile, the interface consumers (IF) dominated in summer/autumn in the PE where the continental influence is less, may have been favored by the highest quality of accumulated flow
of phytodetritus in sediments and a lower content of dissolved oxygen, which perhaps decreased predation pressure and
competition.