eCite Digital Repository
Implications of the divergent use of a suite of estuaries by two exploited marine fish species
Citation
Potter, IC and Chuwen, BM and Hesp, SA and Hall, NG and Hoeksema, SD and Fairclough, DV and Rodwell, TM, Implications of the divergent use of a suite of estuaries by two exploited marine fish species, Journal of Fish Biology, 79, (3) pp. 662-691. ISSN 0022-1112 (2011) [Refereed Article]
![]() | PDF Not available 2Mb |
Copyright Statement
The definitive published version is available online at: http://onlinelibrary.wiley.com/
Official URL: http://onlinelibrary.wiley.com/
DOI: doi:10.1111/j.1095-8649.2011.03051.x
Abstract
Biological characteristics of the marine species King George whiting Sillaginodes punctatus and
Australian herring Arripis georgianus in three seasonally open estuaries (Broke, Irwin and Wilson
Inlets), one permanently open estuary (Oyster Harbour) and one normally closed estuary (Wellstead
Estuary) on the south coast of Western Australia have been determined and compared. Sillaginodes
punctatus enters the seasonally and permanently open estuaries early in life and reaches total
lengths (LT) >280 mm at which it can be legally retained and thus contributes to commercial
and recreational fisheries in these systems. This sillaginid almost invariably emigrates from these
estuaries before reaching its typical size at maturity (LT50) and does not return after spawning
in marine waters. In contrast, virtually all female A. georgianus (¡Ý98%) in the three seasonally
open estuaries and the majority in the normally closed (89¡¤5%) and permanently open estuaries
(83%) exceeded the LT50 of this species at maturity, reflecting the fact that the nursery areas of this
species are predominantly located much further to the east. Although adult females of A. georgianus
in seasonally open and normally closed estuaries had developed mature ovaries by autumn, at which
time they were prevented from migrating to the sea by closure of the estuary mouths, this species
did not spawn in those estuaries. The oocytes in their ovaries were undergoing extensive atresia, a
process that had been incipient prior to oocyte maturation. As the adult females of A. georgianus
in the permanently open Oyster Harbour at this time all possessed resting gonads, i.e. their oocytes
were all previtellogenic, the adults that were present in that estuary earlier and were destined to
spawn in autumn must have emigrated from that permanently open estuary to their marine spawning
areas prior to the onset of gonadal recrudescence. The body masses at length of A. georgianus, which
were almost invariably higher in summer and autumn than in winter and spring, were greater in
the very productive environments of the seasonally open and normally closed estuaries than in the
less productive and essentially marine environment of Oyster Harbour and coastal marine waters.
In general, the same pattern of differences between water bodies was exhibited by the growth of
A. georgianus and by the more restricted data for body mass at LT and growth of S. punctatus.
Despite an increase in anthropogenic activities in Wilson Inlet over the last two decades, the growth
of both species was very similar to that recorded 20 years earlier. The fisheries implications of the
results for the two species are discussed.
Item Details
Item Type: | Refereed Article |
---|---|
Keywords: | Arripis georgianus; atresia; body condition; growth; marine-estuarine opportunist Sillaginodes punctatus |
Research Division: | Agricultural, Veterinary and Food Sciences |
Research Group: | Fisheries sciences |
Research Field: | Aquaculture |
Objective Division: | Animal Production and Animal Primary Products |
Objective Group: | Fisheries - wild caught |
Objective Field: | Fisheries - recreational freshwater |
UTAS Author: | Chuwen, BM (Dr Ben Chuwen) |
ID Code: | 71824 |
Year Published: | 2011 |
Web of Science® Times Cited: | 4 |
Deposited By: | Sustainable Marine Research Collaboration |
Deposited On: | 2011-08-09 |
Last Modified: | 2012-03-09 |
Downloads: | 1 View Download Statistics |
Repository Staff Only: item control page