International Giant Otter Studbook Husbandry and Management

care for the cubs (Schenck & Schenck 1994). Both parents, in addition to the older siblings,
play a significant role in the care of the cubs (Duplaix-Hall 1980; Schenck & Staib 1994). (In
the wild, these animals usually have one litter per year.) Captive giant otters will also bond for
life and both parents care for the cubs together; see below for older siblings helping to care for
their younger siblings in captivity.
Giant otters are social animals and in captivity they should be housed as a single mated
pair with/without offspring, having only one breeding pair. Currently there are a significant
number of otters being housed singly or in single sex pairs and this number has a critically
negative effect on the small captive population. (See Chapter 1 Section 1 for more information.)
Single sex groups, usually males and usually 2 individuals and rarely 3 in a group, have been
kept together successfully, but they must be reared together or introduced with proper
introduction practices (see Section 18 below). Adult females have been reported to live
together, although only a few cases were reported and no other information is known at this
time. (See the exception below.) It is not advisable to introduce adult females. For example,
the following occurred at two institutions, even when females were kept in adjacent enclosures
that were separated with fences that allowed visual-olfactory-acoustic contact for a considerable
time before a physical full-contact introduction was attempted. At the time of the full-contact
introduction, one female was attacked by the other and she died from the serious injuries that
were inflicted upon her (Brasilia Zoo staff, pers. comm.). Note: one female at the time of the
introduction had offspring with her; this is the female that died. At the other institution, “In two
occasions the female defended her territory [by fighting] against another female, which we tried
to introduce,...” (Trebbau, 1972). See another case of failed introduction between temporarily
separated adult females below. (During introductions/re-introductions and more commonly,
females are reported to have injured or killed males and even other females, but also males have
injured other males. Females seem to be the more dominant animal during introductions, and
afterwards once animals are paired, and they seem to initiate fights more often. Females and
males fought against their own sex, females fought males, young otters fought against other
unfamiliar young otters, and adults fought against unfamiliar young animals. All otters that are
unfamiliar with each other or that have been kept together and temporarily separated must be
introduced with proper introduction methods.) In one case an adult male killed a juvenile male
(Kranz pers. comm.) and it is assumed that these animals were familiar with each other.
Trebbau (1972) noted that “...in captivity it is necessary to separate the mature males, as they
tend to fight”. Although overall, reports have shown that adult males have lived together
successfully and it is not unusual that adult males are kept together. E.g. at Philadelphia Zoo
(Sykes-Gatz, pers. comm.) adult males lived together as compatible partners, though often at
feeding times they had small brief quarrels and growling, and sometimes even small fights.
They although did not inflict injury upon one another. These behaviors were similar to and no
less severe than those that captive male and female pairs have carried out; see below.
“Problems [occurred] with the combination of two young males with one older female. Several
occasions [occurred] with aggression and fights with the female being and imposing her
dominance.” (Vera da Silva, pers. comm. 1998). There have been several situations where
mixed sex groups with adult animals, e.g. 2 males and a female, 3 females and a male, have
lived together and it is assumed they co-existed without significant problems, although no
specific reports or other information about these animals were available.
Removal of any family/member of a giant otter group during cub rearing or close to
parturition will likely cause litter loss. It is crucially important to closely monitor a female
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