Chuwen et al.: Changes in the catch rates and length and age at maturity of Cnidoglanis macrocephalus 
259 
It is therefore important that, when such data are not 
already available, managers should initiate sampling 
regimes and analyses aimed at determining whether 
the biological variables for a stock are changing and, if 
so, take the changes into account to ensure that stock 
assessments and management strategies for the future 
are robust. 
Acknowledgments 
Our gratitude is expressed to commercial fishermen O. 
McIntosh and W. Miller for sharing with us their knowl- 
edge of Cnidoglanis macrocephalus, based on many years 
of fishing for that species in Wilson Inlet, to K. Smith 
(Department of Fisheries, Western Australia), and to 
three anonymous reviewers, who provided constructive 
comments on our original submission. Funding was 
provided by the Fisheries Research and Development 
Corporation and South Coast Natural Resource Manage- 
ment, Inc. This project was approved by the Murdoch 
University Animal Ethics Committee (project numbers 
W1145-05 and W2183-08). 
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