Stylet increment analysis is a method of octopus age estimation that quantifies growth rings within stylets (reduced internal shells found in the mantle). This method was applied to wild Octopus pallidus to determine gender and seasonal influences on age and growth. A total of 503 individuals (94 males and 409 females) were aged, revealing that O. pallidus can reach a maximum age of approximately 1.6 yr and that spawning occurs throughout the year. Male octopuses on average were significantly larger (550 and 482 g for males and females, respectively) and older (259 and 243 d for males and females, respectively) than female, and overall growth rates were positively correlated with temperature at hatching. However, these differences were secondary to individual growth heterogeneity. Growth of males ranged from 1.32 to 5.33 % body weight (bw) d-1 and females from 1.55 to 6.9 % bw d-1, with no relationship between age and size evident regardless of sex. Stylet increment analysis is a promising technique that could play a role similar role to statoliths in squid as an ageing tool. © Inter-Research 2008.

Item Type:	Refereed Article
Research Division:	Biological Sciences
Research Group:	Zoology
Research Field:	Invertebrate biology
Objective Division:	Animal Production and Animal Primary Products
Objective Group:	Fisheries - wild caught
Objective Field:	Wild caught edible molluscs
UTAS Author:	Leporati, S (Mr Stephen Leporati)
UTAS Author:	Semmens, JM (Professor Jayson Semmens)
UTAS Author:	Pecl, GT (Professor Gretta Pecl)
ID Code:	54268
Year Published:	2008
Web of Science® Times Cited:	38
Deposited By:	TAFI - Marine Research Laboratory
Deposited On:	2009-02-16
Last Modified:	2012-03-05
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