27
and Verriopoulos 2006b). Thus, abundance is limited by juvenile recruitment rates
rather than adult survival.
Adult size and age vary greatly. The smallest ones live just a few months (e.g.
3 months for the pygmy squid Idiosepius spp., Boletzky 2003b), while the largest
ones (e.g. E� dofleini: Hartwick 1983) are associated with delayed maturity in coldwater habitats and growth to large size (Wood and O’Dor 2000; Farías et al. 2009).
There is a stronger relationship of cephalopod lifespan with temperature than with
body size (Wood and O’Dor 2000). The giant Pacific octopus, E� dofleini, is a coldwater species and unusual in living up to 5 years in captivity (Hartwick 1983).
2.5.2 Movement
A thorough review of cephalopod movement behaviours is beyond the scope of this
chapter (see Semmons et al. 2007) but movement ecology has the potential to affect
husbandry. Long-distance movements may occur for most sepiolids. S� officinalis
makes seasonal onshore–offshore migrations (Guerra 2006), likely due to winter
cooling of the waters. Cuttlefish, with their cuttlebone-based buoyancy mechanism,
can also perform daily vertical migration—upward at night for food and downward
in the daytime (Webber et al. 2000). Migration may also be site focused, as Sepia
apama in Australia makes long-distance migration to gather in restricted areas for
breeding (Hall and Hanlon 2002).
Squid are the most mobile cephalopods (see possible tracking techniques, Semmens et al. 2007). Not only do many species move metres back and forth over the
short term (Mather 2010), they also gather in daytime in the shallows and disperse
over deeper waters at night to feed (Hanlon and Messenger 1996). But larger and
more open-ocean species may make huge lifetime movements. I� illecebrosus gathers to feed off the Grand Banks in northeastern North America; the adults may move
offshore to mate and spawn and their eggs are encased in a large gelatinous capsule
and drift south to off the southeast coast. There the eggs hatch and the young begin
a northward journey (O’Dor and Dawe 1998). Similarly, Dosidicus gigas move
southwards off the coast of South America to feeding grounds, then slowly back to
their equatorial spawning grounds (Nesis 1983), with the newly hatched young dispersing westwards and drifting southeast. With global warming, their range is expanding northwards. Animals with movement patterns as far-ranging and complex
as these will be difficult to raise in the confines of even a large laboratory setting.
While octopuses generally are amenable to confinement within a small environment when provided with a sheltering ‘home’, they eventually will attempt to
leave. This may be tied to the octopus’ short-term occupation of small home ranges
(Mather and O’Dor 1991; Scheel and Bisson 2012), as they only stay in a restricted
area for days or weeks. Thus, there is a ‘laboratory lore’ of how to keep your octopus in the tank. Heavy weights on the lid, locking lids, and outdoor carpeting around
the rim of the tank may act as deterrents. The likelihood of escape is somewhat different amongst species that have been kept in captivity, with O� vulgaris being the
most likely one to escape (Wood and Anderson 2004). It is suggested though not
2 Behaviour
and Verriopoulos 2006b). Thus, abundance is limited by juvenile recruitment rates
rather than adult survival.
Adult size and age vary greatly. The smallest ones live just a few months (e.g.
3 months for the pygmy squid Idiosepius spp., Boletzky 2003b), while the largest
ones (e.g. E� dofleini: Hartwick 1983) are associated with delayed maturity in coldwater habitats and growth to large size (Wood and O’Dor 2000; Farías et al. 2009).
There is a stronger relationship of cephalopod lifespan with temperature than with
body size (Wood and O’Dor 2000). The giant Pacific octopus, E� dofleini, is a coldwater species and unusual in living up to 5 years in captivity (Hartwick 1983).
2.5.2 Movement
A thorough review of cephalopod movement behaviours is beyond the scope of this
chapter (see Semmons et al. 2007) but movement ecology has the potential to affect
husbandry. Long-distance movements may occur for most sepiolids. S� officinalis
makes seasonal onshore–offshore migrations (Guerra 2006), likely due to winter
cooling of the waters. Cuttlefish, with their cuttlebone-based buoyancy mechanism,
can also perform daily vertical migration—upward at night for food and downward
in the daytime (Webber et al. 2000). Migration may also be site focused, as Sepia
apama in Australia makes long-distance migration to gather in restricted areas for
breeding (Hall and Hanlon 2002).
Squid are the most mobile cephalopods (see possible tracking techniques, Semmens et al. 2007). Not only do many species move metres back and forth over the
short term (Mather 2010), they also gather in daytime in the shallows and disperse
over deeper waters at night to feed (Hanlon and Messenger 1996). But larger and
more open-ocean species may make huge lifetime movements. I� illecebrosus gathers to feed off the Grand Banks in northeastern North America; the adults may move
offshore to mate and spawn and their eggs are encased in a large gelatinous capsule
and drift south to off the southeast coast. There the eggs hatch and the young begin
a northward journey (O’Dor and Dawe 1998). Similarly, Dosidicus gigas move
southwards off the coast of South America to feeding grounds, then slowly back to
their equatorial spawning grounds (Nesis 1983), with the newly hatched young dispersing westwards and drifting southeast. With global warming, their range is expanding northwards. Animals with movement patterns as far-ranging and complex
as these will be difficult to raise in the confines of even a large laboratory setting.
While octopuses generally are amenable to confinement within a small environment when provided with a sheltering ‘home’, they eventually will attempt to
leave. This may be tied to the octopus’ short-term occupation of small home ranges
(Mather and O’Dor 1991; Scheel and Bisson 2012), as they only stay in a restricted
area for days or weeks. Thus, there is a ‘laboratory lore’ of how to keep your octopus in the tank. Heavy weights on the lid, locking lids, and outdoor carpeting around
the rim of the tank may act as deterrents. The likelihood of escape is somewhat different amongst species that have been kept in captivity, with O� vulgaris being the
most likely one to escape (Wood and Anderson 2004). It is suggested though not
2 Behaviour