International Giant Otter Studbook Husbandry and Management

another during their separation. This male successfully bred with other females when he was
separated from his sister. When this male although was put back together with his female
sibling they never bred. During the long periods that this brother and sister were kept together,
no litters were born. It is interesting to note that the sister, during separation bred and bore
litters (that did not live) with another male. It may also be possible, that if unrelated giant
otters are reared together or introduced well before they reach sexual maturity, and they
reach sexual maturity together, they will not breed. It is therefore not advisable to keep
otters in the aforementioned situations.
It is advisable to remove cubs from the parents, when the cubs reach 6 months old.
(Captive cubs are normally fully weaned at an age of six months.) Although, because of
limited available data and limited experiences (Corredor, pers. comm. 2003, Brasilia Zoo,
pers. comm. 2002, Flügger 1997) a specific guideline cannot yet be made. Many factors can
affect how successfully juvenile and sub-adult siblings (and adult siblings) are able to co-exist
with and help care for their younger siblings, this therefore affects cub-rearing success. The
success of the few institutions (Corredor, pers. comm. 2003, Brasilia Zoo, pers. comm. 2002,
Flügger 1997) which have experienced this situation has shown that more cubs have died in
such situations than survived. The experiences at each institution are reported below.
Flügger (1997) found it necessary to remove offspring from the parents when the offspring
reached six months old. This is because at Hagenbecks Tierpark, three one-year-old offspring
from the previous litter played too roughly with the new cubs and parents were not able to
defend the young cubs from the exhausting play-ways of the older cubs. The younger cubs died
at 17, 23, and 27 days old. In another litter, three 6.5 month-old cubs, from the previous litter,
competed with the new cubs for the mother’s milk. The younger cubs died at 3, 9, and 60 days
old at which time the remaining 3 cubs were handreared (of which one died at 3 months old
after 4 ½ weeks of handrearing). (Note: the three cubs were emaciated at the time that they
were pulled for handrearing.) In both cases, it was presumed that the mother failed to lactate
sufficient amounts of milk because of the stress. Litter losses resulted in these cases, because of
the stress this type of disturbance caused the parents, the competition for the milk supply and the
affects of the exhausting play-ways on the cubs. The older siblings created the
stresses/disturbances. It is assumed that these otters were housed only or primarily in an indoor
enclosure during the period in which the successive litters were reared (esp. as these litters were
reared during the cold months in Germany). Note: an outdoor enclosure of 255 m² [2, 744.8 ft²]
was also available when it was warm enough for the animals to have outdoor access.
At Cali Zoo, in at least two successive litters, of which 3 cubs were born in one litter and 1 cub
was born in the following litter, 2 cubs survived, one from each litter, when juveniles and/or
subadults were also present (Corredor, pers. comm.). This is a 50% success rate for these
particular two litters. Although it is important to note that two of these cubs died of a bacterial
infection caused by the wet/very damp conditions within the dens. Updated records showed that
two following litters, reared by the same parents and in a group with a similar social structure as
aforementioned, failed to survive.
It is interesting to note that no births were reported to occur at one institution for a 2 year
period, during which the breeding pair was housed with their offspring, until the offspring
reached 2 years old (Brasilia Zoo, pers. comm. 2002). Concerns/reports were that some of the
births were suspected to have been undetected (i.e. cubs were eaten and no remains were found)
at this institution in the past and this suggested that more litters may have been born than were
recorded (Louzada da Silva, pers. comm.). I.e. the cubs were born and raised in natural
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