Title The reproductive biology of two epibenthic species of Antarctic nototheniid fish of the genus Trematomus
Author La Mesa, M.; Caputo, V.; Eastman, J.T.
Author Affil La Mesa, M., CNR, Istituto di Scienze Marine, Sede di Ancona, Ancona, Italy. Other: Universita Politecnica delle Marche, Italy; Ohio University
Source Antarctic Science, 20(4), p.355-364, . Publisher: Cambridge University Press, Cambridge, United Kingdom. ISSN: 0954- 1020
Publication Date Aug. 2008
Notes In English. NSF Grant ANT-0436190. 57 refs. GeoRef Acc. No: 287455
Index Terms Southern Ocean--Ross Sea; behavior; Chordata; ecology; histology; physiology; Pisces; reproduction; Ross Sea; Southern Ocean; Vertebrata
Abstract Trematomus eulepidotus and T. loennbergii are two of the most common epibenthic fish in the waters of the High Antarctic continental shelf. Since the reproductive biology of these species has not been studied in the Ross Sea, we provide a macroscopic and histological analysis of the reproductive effort and gonadal development in both sexes. Most samples were collected during benthic trawl surveys in the south- western Ross Sea in the 1996 and 1997 summer seasons. The aim of the study was to define the reproductive characteristics of these two sympatric species and to examine the hypothesis that different reproductive strategies mitigate interspecific competition. We found that, in common with most Antarctic notothenioids, both species possess a suite of similar reproductive strategies including delayed sexual maturity, prolonged gametogenesis, group-synchronous oocyte maturation, a single spawning event per year and iteroparity. Both species show a comparable reproductive effort in terms of potential fecundity with between 2000 and 20 000 eggs per female per season. Nevertheless, the two species exhibited a considerable difference in the timing of the breeding season, spawning in summer (T. loennbergii), This gives rise to a mismatch in the time of appearance of larvae in the environment and probably leads to reduced competition.
URL http://hdl.handle.net/10.1017/S095410200800103X
Publication Type journal article
Record ID 84703