Hostname: page-component-77c89778f8-m8s7h Total loading time: 0 Render date: 2024-07-16T17:58:21.315Z Has data issue: false hasContentIssue false

Population structure, growth and production of Laeonereis culveri (Nereididae: Polychaeta) in tidal flats of Río de la Plata estuary, Argentina

Published online by Cambridge University Press:  13 March 2006

J.P. Martin
Affiliation:
Centro de Investigaciones de Puerto Deseado, Universidad Nacional de la Patagonia Austral, CC 238 (9050), Puerto Deseado, Argentina Departamento de Ciencias Marinas, Universidad Nacional de Mar del Plata, CC 43 (7600) Mar del Plata, Argentina
R. Bastida
Affiliation:
Departamento de Ciencias Marinas, Universidad Nacional de Mar del Plata, CC 43 (7600) Mar del Plata, Argentina Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET)

Abstract

A benthic survey was carried out from November 1998 to December 1999 in the tidal flats of Bahía Samborombón (Río de la Plata estuary, Argentina), in order to study the population structure, growth and secondary production of Laeonereis culveri. The samples were collected monthly in two intertidal areas with different environmental characteristics (San Clemente Creek and Punta Rasa). Growth was analysed using computer-based methods of length–frequency data (ELEFAN), and the secondary production was estimated by Crisp's and Hynes & Coleman's methods. Laeonereis culveri were recruited throughout the year, with two main peaks during spring and autumn. The autumn cohort showed growth rate (K) of 2 in San Clemente Creek and 1.8 in Punta Rasa. The seasonal oscillation of growth pointed out that worms grow very slowly during winter months. The life span of this cohort ranged from 15 to 17 months. The spring cohort showed higher growth rates in both sampled areas (K=3.3 in Punta Rasa and 3.1 in San Clemente Creek), whereas the growth oscillation showed similar values to those of the autumn cohort. The lowest growth rate was found in January and the life span was 9.5 months. The annual mean biomass in San Clemente Creek was 5.44 g m−2, with a mean production of 40.8 and 43.8 g m−2 y−1, according to the method used, and a production/biomass (P/B) ratio of 7.5 and 8 y−1 respectively. In Punta Rasa, the annual mean biomass (2.69 g m−2) and mean secondary production (19.44 and 23.61 g m−2 y−1, according to the method used) were lower than in San Clemente Creek, nevertheless the P/B ratio (7.2 and 8.7 y−1) was similar. The high secondary production and P/B ratio observed suggest that L. culveri transfer an important biomass to higher trophic levels, pointing out the very important role that this polychaete plays in the energy flux of this coastal estuarine ecosystem.

Type
Research Article
Copyright
2006 Marine Biological Association of the United Kingdom

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)