Variable growth rates of the tropical estuarine fish barramundi Lates calcarifer (Bloch) under different freshwater flow conditions
Abstract:Relationships between freshwater flows and growth rates of the opportunistic predatory finfish barramundi Lates calcarifer in a dry tropical estuary were examined using data from a long-term tag-recapture programme. Lagged effects were not investigated. After accounting for length at release, time at liberty and seasonal variation (e.g. winter, spring, summer and autumn), growth rates were significantly and positively related to fresh water flowing to the estuary. Effects were present at relatively low levels of freshwater flow (i.e. 2·15 m3 s−1, the 5th percentile of the mean flow rate experienced by fish in the study during time at liberty). The analysis, although correlative, provides quantitative evidence to support the hypothesis that freshwater flows are important in driving the productivity of estuaries and can improve growth of species high in the trophic chain.
Document Type: Regular Paper
Affiliations: 1: Department of Primary Industries and Fisheries, Animal Research Institute, Locked Mail Bag 4, Moorooka 4105, Australia 2: Department of Primary Industries and Fisheries, Southern Fisheries Centre, P. O. Box 76, Deception Bay 4508, Australia 3: Infofish Services, P. O. Box 9793, Frenchville 4701, Australia
Publication date: August 1, 2006