eCite Digital Repository

Spawning patterns provide further evidence for multiple stocks of sardine (Sardinops sagax) off eastern Australia

Citation

Sexton, SC and Ward, TM and Stewart, J and Swadling, KM and Huveneers, C, Spawning patterns provide further evidence for multiple stocks of sardine (Sardinops sagax) off eastern Australia, Fisheries Oceanography, 28, (1) pp. 18-32. ISSN 1054-6006 (2019) [Refereed Article]

Copyright Statement

Copyright 2018 John Wiley & Sons Ltd.

DOI: doi:10.1111/fog.12383

Abstract

Previous studies have suggested that sardine, Sardinops sagax, off eastern Australia spawns across its entire range when habitat conditions are suitable. However, recent studies have suggested that separate sub‐populations and spawning groups may occur in the region. Spawning patterns off eastern Australia were investigated using data collected during nine ichthyoplankton surveys conducted between 19972015, and adult reproductive data obtained from ad hoc commercial sampling off New South Wales (NSW). The egg surveys covered the known distribution of sardine off eastern Australia and included year‐round sampling in the northern and southern parts of this range. Egg distributions and analysis of gonadosomatic indices identified two spatio‐temporally separate spawning groups; one occurring off southern Queensland to northern NSW during late winter and early spring, and a smaller group off eastern Tasmania to southern NSW during summer. Most eggs were collected from waters 5090m deep, with sea surface temperatures of 1823C. Additive modelling indicated depth was the most significant factor driving selection of spawning habitat, followed by the interaction of month and latitude. Low egg densities were recorded in waters between 3437S, despite conditions within the ranges suitable for spawning. The presence of two spawning groups of sardine off eastern Australia supports recent findings that two sub‐populations occur in the region. Findings of this study will help to optimise the spatio‐temporal extent of future egg surveys and further confirm the need to coordinate future management of each sub‐population among relevant jurisdictions.

Item Details

Item Type:Refereed Article
Keywords:sardines, fisheries, South East Australia, East Australian Current, multijurisdictional management, small pelagic fisheries, spawning discontinuity, spawning habitat extension, spawning habitat selection, stock structure
Research Division:Biological Sciences
Research Group:Ecology
Research Field:Marine and estuarine ecology (incl. marine ichthyology)
Objective Division:Environmental Management
Objective Group:Management of Antarctic and Southern Ocean environments
Objective Field:Biodiversity in Antarctic and Southern Ocean environments
UTAS Author:Swadling, KM (Associate Professor Kerrie Swadling)
ID Code:127553
Year Published:2019 (online first 2018)
Web of Science® Times Cited:33
Deposited By:CRC-Antarctic Climate & Ecosystems
Deposited On:2018-08-03
Last Modified:2019-02-26
Downloads:0

Repository Staff Only: item control page