Open Access Repository

Modelling size-at-age in wild immature female octopus: a bioenergetics approach


Downloads per month over past year

André, J, Pecl, GT, Grist, EPM, Semmens, JM, Haddon, M and Leporati, S 2009 , 'Modelling size-at-age in wild immature female octopus: a bioenergetics approach' , Marine Ecology Progress Series, vol. 384 , pp. 159-174 , doi: 10.3354/meps08035.

André_et_al_200...pdf | Download (789kB)
Available under University of Tasmania Standard License.


The population dynamics of cephalopods are poorly understood because intra-specific
size-at-age is characteristically variable. Much of the variation observed is attributed to temperature
and food, but other generally overlooked factors such as hatchling size and inherent growth capacities
also affect size-at-age. In the present paper, we investigated the relative influence of the principal
abiotic (environmental temperature) and biotic (food consumption, hatchling size, inherent
growth capacity) factors affecting size-at-age in immature octopus. Using a bioenergetics model and
size-at-age data of wild-caught immature Octopus pallidus, we simulated the juvenile growth trajectories
of individuals hatched in different seasons (summer, autumn and winter) based on food availability,
metabolism, environmental temperature and individual variability, under an assumption of 2-
phase growth. Simulations predict that the effect of hatchling size on size-at-age was secondary to
that of inherent growth capacity. Projections suggest that wild immature populations comprise a mixture
of individuals displaying exponential growth and 2-phase growth and that the proportion of each
depends primarily on the individuals’ inherent growth capacities and food availability. High food
intake was projected to decrease the number of individuals displaying 2-phase growth by delaying
the transition between the 2 growth phases, resulting in larger individuals. Overall, individuals
hatched in summer grew to larger sizes and matured earlier than individuals hatched in autumn or
winter, independent of food availability. The size-at-age distribution of the summer and autumn
cohorts tended to become bimodal under certain food intake levels, which highlights the importance
of coupling size data with accurate age estimates in future octopus population studies.

Item Type: Article
Authors/Creators:André, J and Pecl, GT and Grist, EPM and Semmens, JM and Haddon, M and Leporati, S
Keywords: Early life history · Energy balance · Individual-based model · Pale octopus
Journal or Publication Title: Marine Ecology Progress Series
ISSN: 0171-8630
DOI / ID Number: 10.3354/meps08035
Additional Information:

Copyright © 2009 InterResearch. This article has been integrated as chapter four of a doctoral dissertation available via the related url.

Related URLs:
Item Statistics: View statistics for this item

Actions (login required)

Item Control Page Item Control Page