International Giant Otter Studbook Husbandry and Management

Inbreeding, physical, behavioral, and pair compatibility problems should be considered
for repeated breeding or rearing failure, providing appropriate husbandry and
management is used during cub-rearing and at all other times. Hagenbeck and Wünnemann
(1992) suggest that giant otters “show individual preferences when accepting a mate”; hence,
repairing mates should be considered when pairs show clear signs of extensive pair
incompatibility. Although a pair should not be determined incompatible just on the
observations of brief temporary quarrels, growling, etc. seen between group members during
the normal day. For example, it is quite common that captive giant otters, even truly compatible
pairs, will growl at each other and sometimes even briefly fight (not inflicting injury), when
they are eating fish. They will often try to keep some distance apart when they are eating. One
individual may beg or show the other that he/she wants the other’s fish and one or the other may
growl or make defensive/offensive bodily movements in addition. [These behaviors are also
seen among wild Pteronura family group members. At least among adults “each otter catches
its own prey and consumes it immediately…and there is no food sharing” (Duplaix 1980).]
Many other negative, aggressive, or domineering behaviors must be displayed and on a
continuing basis to determine if the pair is incompatible. Note: the individual “personality type”
(i.e. very dominant, submissive, patient, nervous etc.) of each otter can affect pairing success,
therefore this should be considered when selecting possible mates and partners as well.
It as well should not be assumed because of certain behaviors, that the presence of fathers
during cub-rearing will have a negative impact on the success of cub-rearing. For example,
it seems to be normal, both in captivity and in the wild (Staib 2002), that fathers will often take
cubs out of the den/nestbox and the mothers will immediately take action to return the cubs to
the den/nestbox. When this behavior is not abnormally frequent or excessive, it should not be
determined as harmful. Parents at Dortmund Zoo (Sykes-Gatz pers. obs.), Hagenbeck Tierpark
(Flügger pers. comm.) and Cali Zoo (Corredor pers. comm.) have all been observed to carry out
these behaviors. In at least the first days after birth, mothers have also been seen to be a little
protective over their cubs when the father tries to become involved with the cubs. This as well
should not be seen as abnormal behavior. Soon afterwards, the father will become equally
involved (and his involvement well accepted by his mate) in the care of the cubs. Providing
multiple nestboxes or having multiple underground dens gives fathers a place to go and
mother’s a little free space during these times. As well, it is crucial that enclosures are properly
designed and furnished to help occupy the father’s and mother’s attentions on something else
rather than only the cubs.
It may also be possible that when siblings from the same litter are reared and reach sexual
maturity together, they will not breed if they are housed together as a potential breeding
pair. This situation and failure to reproduce is known to have occurred in three cases, at three
different zoos (Louzada da Silva, pers. comm. provided information about the pairs’ family
history at Brasilia and Sorrocaba Zoos; Wünnemann 1991). For example, at Hagenbeck
Tierpark, a female was kept with her brother, who she grew up with, until she was at least 3
years old. This pair had rare and failed mating attempts and no pregnancies resulted.
Wünnemann noted that this male was not well experienced at mating [maybe he did not
penetrate the female]. This pair was then separated, the female was paired with a new partner
and she had a litter. A litter was born at Cuiaba Zoo in 1994 and a pair from this litter was
transferred to Sorrocaba Zoo and no litters were born from this pair during their lifetime,
although they were kept together their entire lives (which was at least 6 years or more). (More
detailed information regarding this pair is not known, so other explanations for breeding failure
may also have been possible.) At Brasilia Zoo, a brother and sister that were reared together
were eventually separated, but they were kept in visual-acoustic-olfactory contact with one
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