Population aspects of Themisto gaudichaudii, a key species in the food web of the southern Patagonian Shelf
Keywords:Themisto gaudichaudii, population dynamics, life history, southern Patagonian shelf
With the aim of studying population aspects of Themisto gaudichaudii, samples from 12 research cruises carried out in different seasons were analyzed. Abundances and biomass were among the highest recorded for the species throughout its distribution range. These parameters showed a strong seasonal variation with the highest values recorded during spring-summer (maximum at the end of the period: 16.6 ind. m-3 and 20 mg m-3), and minimum values in winter (0.9 ind. m-3 and 1.7 mg m-3). The highest concentrations were located between 50° S and 52° S in the Bahía Grande. These biomasses would be developed by adaptations to local environmental conditions, particularly to high food availability and temperature. The population of T. gaudichaudii analyzed presents a more extended reproductive period (spring-summer), a larger number of cohorts (two main cohorts) and a smaller size at maturity (~ 10 mm) than other populations at similar latitudes. These adaptations would favor a larger population of T. gaudichaudii placing the ecosystem of the southern Patagonian shelf among the most favorable for the development of the species throughout its global distribution range.
† Dr. Hermes W. Mianzan passed away on July 9, 2014.
How to Cite
Copyright (c) 2015 Luciano Padovani, María Delia Viñas, Marina Sabatini, Gustavo Álvarez Colombo, Hermes Mianzan †
This work is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International License.
Authors of articles published in Marine and Fishery Sciences retain copyright on their articles, except for any third-party images and other materials added by Marine and Fishery Sciences, which are subject to copyright of their respective owners. Authors are therefore free to disseminate and re-publish their articles, subject to any requirements of third-party copyright owners and subject to the original publication being fully cited. Visitors may also download and forward articles subject to the citation requirements. The ability to copy, download, forward or otherwise distribute any materials is always subject to any copyright notices displayed. Copyright notices must be displayed prominently and may not be obliterated, deleted or hidden, totally or partially.
This journal offers authors an Open Access policy. Users are allowed to read, download, copy, distribute, print, search, or link to the full texts of the articles, or use them for any other legal purpose within the Creative Commons 4.0 license (BY-NC-SA), without asking prior permission from the publisher or the author. This is in accordance with the BOAI definition of Open Access.