30
both sexes are exhausted. Squid die within hours. Sneaker males of L� reynaudii
(Hanlon et al. 2002), as well as other squid (e.g. D� gigas: Nigmatullin et al. 2001)
and cuttlefish (Hanlon et al. 1999a) mate in the head-to-head position. Mating behaviour may be variable and dependent on context (Hanlon et al. 2002; Jantzen and
Havenhand 2003a). Thus, there are opportunities to manipulate the onset of spawning under cultivation, although courtship and mating behaviours may be inseparable
from male–male aggression.
Male octopuses may use chemoreception to locate receptive females (Voight
1991a; Di Cristo et al. 2005). Populations may have a single (Ambrose 1988) or
two (Katsanevakis and Verriopoulos 2006b) spawning (and hence recruitment)
peaks per year, with post-settlement mortality rates > 50 % within 3 months. Octopuses are not territorial and males apparently do not guard receptive females
(Voight 1991b; but for exception see Huffard et al. 2010). During precopulatory
behaviours, the male approaches the female and extends the hectocotylus towards
her. If not rebuffed, males touch the female with the ligula (which females may use
in assessment of male maturity), and if receptive, females remain motionless (e.g.
Paroctopus digueti: Voight 1991b). In some species, females also may approach
males (in captivity, Cheng and Caldwell 2000), and males may not always distinguish between male and female potential mates, or even among species (Lutz and
Voight 1994; Cheng and Caldwell 2000). Copulation then occurs in positions varying from at arm’s length to the male engulfing the female beneath his web. The male
inserts the hectocotylus into the female mantle cavity. Mating may last up to several
hours and is typically terminated by the female (e.g. Octopus joubini: Mather 1978;
P� digueti: Voight 1991b; Hapalochlaena lunulata: Cheng and Caldwell 2000). In
at least some species, more complex male mating strategies may involve sneaker males, mate guarding, and competition (Huffard et al. 2008). Thus, aspects of
mating, including male initiation of mating and mating technique, may depend on
crowding or familiarity with territory (Mather 1978), and so mating under cultivation may differ from in the wild.
2.5.5 Egg-Care Behaviours
Cuttlefish selectively deposit their eggs on support, such as in crevices among appropriate corals (Boletzky 1998). Squid deposit their eggs, often en masse, on or
under appropriate bottom substrate, such as in sand, under rocks, or on sessile organisms, anchor lines or other support, or in pelagic balloons (Oegopsids). Except
for family Gonatidae and Bathyteuthida squid (Bush et al. 2012), neither squid nor
cuttlefish are known to exhibit egg-brooding behaviours.
Most small-egged octopus species cement festoons of eggs to sheltered hard
substrate, such as inside the roof of a den. Eggs are laid over several days. Females
typically stop eating just before or about the time of egg laying, although this is
not invariant. Females then tend eggs, manipulating each strand with arm tips and
blowing jets of water across them. Dead eggs are removed, as may be any showing signs of fungi or algae (Batham 1957; Gabe 1975; Anderson and Wood 2012).
J. Mather and D. Scheel
both sexes are exhausted. Squid die within hours. Sneaker males of L� reynaudii
(Hanlon et al. 2002), as well as other squid (e.g. D� gigas: Nigmatullin et al. 2001)
and cuttlefish (Hanlon et al. 1999a) mate in the head-to-head position. Mating behaviour may be variable and dependent on context (Hanlon et al. 2002; Jantzen and
Havenhand 2003a). Thus, there are opportunities to manipulate the onset of spawning under cultivation, although courtship and mating behaviours may be inseparable
from male–male aggression.
Male octopuses may use chemoreception to locate receptive females (Voight
1991a; Di Cristo et al. 2005). Populations may have a single (Ambrose 1988) or
two (Katsanevakis and Verriopoulos 2006b) spawning (and hence recruitment)
peaks per year, with post-settlement mortality rates > 50 % within 3 months. Octopuses are not territorial and males apparently do not guard receptive females
(Voight 1991b; but for exception see Huffard et al. 2010). During precopulatory
behaviours, the male approaches the female and extends the hectocotylus towards
her. If not rebuffed, males touch the female with the ligula (which females may use
in assessment of male maturity), and if receptive, females remain motionless (e.g.
Paroctopus digueti: Voight 1991b). In some species, females also may approach
males (in captivity, Cheng and Caldwell 2000), and males may not always distinguish between male and female potential mates, or even among species (Lutz and
Voight 1994; Cheng and Caldwell 2000). Copulation then occurs in positions varying from at arm’s length to the male engulfing the female beneath his web. The male
inserts the hectocotylus into the female mantle cavity. Mating may last up to several
hours and is typically terminated by the female (e.g. Octopus joubini: Mather 1978;
P� digueti: Voight 1991b; Hapalochlaena lunulata: Cheng and Caldwell 2000). In
at least some species, more complex male mating strategies may involve sneaker males, mate guarding, and competition (Huffard et al. 2008). Thus, aspects of
mating, including male initiation of mating and mating technique, may depend on
crowding or familiarity with territory (Mather 1978), and so mating under cultivation may differ from in the wild.
2.5.5 Egg-Care Behaviours
Cuttlefish selectively deposit their eggs on support, such as in crevices among appropriate corals (Boletzky 1998). Squid deposit their eggs, often en masse, on or
under appropriate bottom substrate, such as in sand, under rocks, or on sessile organisms, anchor lines or other support, or in pelagic balloons (Oegopsids). Except
for family Gonatidae and Bathyteuthida squid (Bush et al. 2012), neither squid nor
cuttlefish are known to exhibit egg-brooding behaviours.
Most small-egged octopus species cement festoons of eggs to sheltered hard
substrate, such as inside the roof of a den. Eggs are laid over several days. Females
typically stop eating just before or about the time of egg laying, although this is
not invariant. Females then tend eggs, manipulating each strand with arm tips and
blowing jets of water across them. Dead eggs are removed, as may be any showing signs of fungi or algae (Batham 1957; Gabe 1975; Anderson and Wood 2012).
J. Mather and D. Scheel