Estuarine habitat use by juvenile dusky kob Argyrosomus japonicus (Sciaenidae), with implications for management

The spatial and temporal area-use patterns of estuarine-dependent juvenile dusky kob Argyrosomus japonicus in the Great Fish Estuary, South Africa, were examined using acoustic telemetry. In all, 29 individuals (307-400 mm total length) were surgically equipped with individually coded transmitters a...

Full description

Saved in:
Bibliographic Details
Published in:African journal of marine science Vol. 30; no. 2; pp. 247 - 253
Main Authors: Cowley, PD, Kerwath, SE, Childs, A-R, Thorstad, EB, Økland, F, Næsje, TF
Format: Journal Article
Language:English
Published: Taylor & Francis Group 01.09.2008
Subjects:
ACOUSTIC TELEMETRY
ARGYROSOMUS JAPONICUS
Brackish
FISHERIES MANAGEMENT
Marine
MOVEMENT BEHAVIOUR
NURSERY HABITAT
Sciaenidae
SOUTH AFRICA
South Africa
PSW, South Africa, Cape Prov., Great Fish Estuary
ISSN:1814-232X, 1814-2338
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:The spatial and temporal area-use patterns of estuarine-dependent juvenile dusky kob Argyrosomus japonicus in the Great Fish Estuary, South Africa, were examined using acoustic telemetry. In all, 29 individuals (307-400 mm total length) were surgically equipped with individually coded transmitters and monitored for a period of up to 195 days using an array of 11 moored data-logging acoustic receivers. Tagged dusky kob spent most time in the estuary (84%), compared with neighbouring marine (13%) and riverine (4%) environments. Tagged fish made extensive use of the estuary from the mouth to between 6.4 km and 10.3 km upstream, and spent approximately equal proportions of time at each of the seven receivers located between 0.5 km and 6.5 km from the mouth. A total of 18 fish undertook sea trips of a mean duration of 3.5 days, whereas three individuals made riverine excursions (mean duration = 7.3 days). A total of 12 (41%) tagged fish was captured in the estuary prior to, during or after the monitoring period. These findings highlight the importance of estuaries as critical nursery areas, and that the use of these habitats by dusky kob should be better reflected in the management arrangements for this fishery species.
Bibliography:ObjectType-Article-2
SourceType-Scholarly Journals-1
ObjectType-Feature-1
content type line 23
ISSN:1814-232X
1814-2338
DOI:10.2989/AJMS.2008.30.2.5.555