出版社：Government of Western Australia / Department of Fisheries
摘要：The sizes at which female and male western rock lobster Panulirus cygnus become mature were
examined over 32 years from records at six localities along the coast of Western Australia. The
size of males at maturity was estimated from a subset of these data by a morphometric and a
physiological method, with both producing statistically similar results. Males were larger at first
maturity than females at the same sites. For both sexes, the sizes at first maturity at each location
correlated (P<0.05) with the mean annual water temperature at that location, decreasing from
south to north along the mainland coast and being smallest at the offshore Abrolhos Islands.
Smaller sizes at maturity were recorded for both sexes than have been published previously.
One certain explanation for these differences is that management measures protecting females
with ovigerous setae, have distorted size compositions and the ratio of immature to mature
females, thereby increasing the likelihood of capturing small mature females. However, these
fishing effects cannot fully account for the progressive decline in CL50 observed over the past
20 years. Other possible hypotheses considered include increases in water temperature over this
period, as well as whether this change could be consistent with a genotypic response caused by
the selective removal of large lobsters combined with high exploitation rates.
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