Should we isolate octopuses? Impact of social environment on the
octopus’s cognitive abilities as an indirect indicator of animal welfare
Dates: été 2017
Host Institution: Dr. Graziano Fiorito, Stazione Zoologica Anton Dohrn, Napoli
Co-supervision: Dr. Aurore Avarguès-Weber, Centre de Recherches sur la Cognition Animale (CNRS/Université Toulouse 3), Toulouse.
Contact : aurore.avargues-weber [ chez ] univ-tlse3.fr.
Please add with your application in French or English, a CV, letter of motivation and name(s) of referent(s)
Project:
Context
When maintained in captive conditions, octopuses are usually kept in
isolation in individual tanks to prevent territorial behaviour and
agonistic encounters occasionally reported to cause cannibalism (Ibáñez
Keyl, 2010). On the other hand, aquaculture practice requires
maximization of growth and often uses group-living as a choice
(Estefanell et al., 2012). However, most octopus species have
solitary-living habit, which further support isolated rearing
conditions.
These animals are very attentive to conspecifics’ behaviour; they
express typical social communication through body visual patterns
(Packard Sanders, 1971; Scheel et al., 2016) and demonstrate social
learning capabilities (Fiorito Scotto, 1992): octopuses (Octopus
vulgaris) indeed acquire by observation the preference between
artificial preys shown by a conspecific individual that was previously
trained to associate this artificial stimulus with a food reward. This
experiment shows that this solitary-living species naturally acquired
socially provided information.
It is therefore possible that continuous social visual interactions
(see also Tricarico et al., 2011) would provide a stimulating cognitive
context due to environmental enrichment and information gathered from
the conspecific. The question is whether a social context may be
acceptable (sensu Bracke et al., 1999) or even stimulating in a rearing
context for a solitary-living animal with adequate cognitive
capabilities.
In this project, we wish to compare learning performance and
classical welfare indicators between octopuses raised either in
isolation or with constant visual access to the tank of an other
octopus.
Workplan
Octopuses (Octopus vulgaris) collected in Naple’s bay will be reared
in individual tanks. Half of them will nevertheless have the
possibility to see another individual in an adjacent tank separated by a
transparent divider. Such a dual tank would prevent physical aggression
between animals. The animal will be allocated in pairs on the basis of
similar body size to avoid asymmetrical social influence as dominance in
conflict seems established through size judgement in octopus (Boyle,
1980). The octopuses will then be trained and tested for simple
associative visual learning first (presentation of two visual objects,
only one being associated with food) but also for conceptual learning
abilities (rule learning: ‘Delayed-Matching-To-Sample’ task and/or
numerical abilities). Cognitive performances will be compared between
socially isolated and pairs rearing conditions. Parameters such as time
spent hidden or in exploratory behaviour and latency to catch food would
be recor!
ded as indicators of the animals’ welfare in both conditions.
Expected results and outcomes
- Observation of the influence on animal basic behaviours
(exploration – food catching) of the presence of a social environment on
a long term perspective (2 months)
- Information on octopuses’ abilities to solve relational rule
learning task as not yet demonstrated to our knowledge in cephalopods
despite the known sophistication of their neural system and behaviours
(Borrelli Fiorito, 2008; Edelman Seth, 2009).
- Elements about the emulative or negative influence of conspecific visual perception on cognitive performance.
Budget
Travel, accommodation and basic living expenses will be covered.
Backgrounds/skills requested
A background in ethology, cognition and prior experimental expertise would be appreciated.
Candidates with a master degree will be favoured but other candidates welcomed.
References
. Borrelli, L., Fiorito, G. (2008). Behavioral analysis of
learning and memory in cephalopods. In J. J. Byrne (Ed.), Learning and
memory: A comprehensive reference (pp. 605-627). Oxford: Academic Press.
. Boyle, P. (1980). Home occupancy by male Octopus vulgaris in a large seawater tank. Anim Behav, 28(4), 1123-1126.
. Bracke, M. B., Spruijt, B. M., Metz, J. H. (1999). Overall
animal welfare reviewed. Part 3: Welfare assessment based on needs and
supported by expert opinion. NJAS wageningen journal of life sciences,
47(3), 307-322.
. Edelman, D. B., Seth, A. K. (2009). Animal consciousness: a synthetic approach. Trends Neurosci, 32(9), 476-484.
. Estefanell, J., Roo, J., Fernández-Palacios, H., Izquierdo, M.,
Socorro, J., Guirao, R. (2012). Comparison between individual and
group rearing systems in Octopus vulgaris (Cuvier, 1797). Journal of the
World Aquaculture Society, 43(1), 63-72.
. Fiorito, G., Scotto, P. (1992). Observational learning in
Octopus vulgaris. Science, 256(5056), 545- 547. doi:
10.1126/science.256.5056.545
. Ibáñez, C. M., Keyl, F. (2010). Cannibalism in cephalopods. Reviews in Fish Biology and Fisheries, 20(1), 123-136.
. Packard, A., Sanders, G. D. (1971). Body patterns of Octopus
vulgaris and maturation of the response to disturbance. Anim Behav,
19(4), 780-790.
. Scheel, D., Godfrey-Smith, P., Lawrence, M. (2016). Signal use
by octopuses in agonistic interactions. Current Biology, 26(3), 377-382.
. Tricarico, E., Borrelli, L., Gherardi, F., Fiorito, G. (2011). I
know my neighbour: individual recognition in Octopus vulgaris. PLoS
ONE, 6(4), e18710.
