Logo image
Back
The biology of the catfish Cnidoglanis macrocephalus (Plotosidae) in an Australian estuary
Journal article   Peer reviewed

The biology of the catfish Cnidoglanis macrocephalus (Plotosidae) in an Australian estuary

S.A. Nel, I.C. Potter and N.R. Loneragan
Estuarine, Coastal and Shelf Science, Vol.21(6), pp.895-909
1985
DOI: https://doi.org/10.1016/0272-7714(85)90081-2
url
Link to Published Version *Subscription may be requiredView

Abstract

This paper describes the age structure, growth, diet and aspects of gonadal development in the cobbler, Cnidoglanis macrocephalus (Valenciennes), in the large Swan estuary in south-western Australia between August 1982 and June 1984. Analysis of otolith annuli showed that while the 0+ to 3+ age classes were regularly represented in monthly samples, the 4+ and more particularly the 5+ and 6+ were much less abundant. The weighted means for the back calculated lengths at the end of the first to fourth years of life were 181 mm (≡ 26 g), 314 mm (≡ 156 g), 418 mm (≡ 410 g) and 518 mm (≡ 833 g) respectively. The mean length at the end of the second year of life was similar to the minimum legal size for capture by commercial fishermen (320 mm). The von Bertlanffy growth curve calculated from the back calculated lengths was Lt = 917 [1 − e−0·20(t + 0·11)]. The relative weight of mulluscs, crustaceans and polychaetes in the intestine varied markedly between small and large fish, apparently reflecting differences in the size of these prey. The large mean diameter of mature eggs () was correlated with a low mean absolute fecundity (2078). Trends shown by egg size, gonadosomatic index and time of appearance of spent females indicate that spawning takes place between October and December. The attainment of sexual maturity is both age- and size-dependent. Although sexually maturing and occasionally spent fish were found in the lower estuary, meristic values, commercial catch statistics and other data indicate that the cobbler found in the Swan estuary are part of a population which typically spawns at sea.

Details

UN Sustainable Development Goals (SDGs)

This output has contributed to the advancement of the following goals:

#13 Climate Action
#14 Life Below Water

Source: InCites

Metrics

53 Record Views
29 Times Cited - Web of Science

InCites Highlights

These are selected metrics from InCites Benchmarking & Analytics tool, related to this output

Citation topics
3 Agriculture, Environment & Ecology
3.2 Marine Biology
3.2.1182 Coastal Vegetation
Web Of Science research areas
Marine & Freshwater Biology
Oceanography
ESI research areas
Plant & Animal Science
Logo image