International Giant Otter Studbook Husbandry and Management

maturity (i.e. at 2 years old), they then could be mated with non-related individuals to form a
breeding pair. Although, because the situation of giant otters in captivity is so critical, cubrearing
success has been so poor, there are very limited experiences with these matters, and
many zoos do not have ideal situations, little chance should be taken for experimentation.
Research should continue on how cub-rearing and breeding success are effected by the
following factors. All of the factors below must be considered for appropriate conclusions to be
drawn. E.g. when cubs are reared to independence in inappropriate enclosure conditions, this
does not validate that the enclosure conditions were appropriate or responsible, either in part or
entirely, for the success. All factors must be accounted for to correctly explain this outcome.
Cub rearing success can be effected by the quality, furnishings, design, and size of indoor and
outdoor enclosures, the extent of isolation/privacy from human disturbances and presence
available, husbandry and management practices, and the duration, intensity, frequency, and
familiarity of the disturbance (see below). It also can be effected by stress (esp. caused by
human disturbances and/or inappropriate enclosure conditions), parental and sibling cub neglect
and abuse (i.e. resulting from the stress), individual otter personality and history (e.g. physical
and behavioral health problems), the degree of experience that each parent and if present, older
offspring has with rearing cubs, and family social structure (i.e. the age of any older offspring
present at the time of the new litter birth, whether the sire is present etc.). 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. If siblings from the same litter were reared and reached sexual maturity
together or if unrelated giant otters were reared together or introduced well before they reached
sexual maturity, and they reached sexual maturity together, these factors should be evaluated for
how they affect breeding success. Note: enclosure conditions that can affect cub-rearing
success include: the appropriateness of land to water ratios, land and floor substrates, deep
digging area sizes, other land and water area designs and locations, enclosure size, and the
designs and locations of dens, nestboxes, areas/hillsides for natural underground dens, animal
shift doors, and keeper doors. They also include whether natural otter dug underground dens
and/or expansive enclosures are available and the amount of enrichment and privacy designs
available within an enclosure. The husbandry practices that can affect cub-rearing success
include: how well enclosures and nestbox, den, and natural underground den areas are isolated
from human disturbances and presence, how well caretakers limit and minimize their activities
and carry them out so that they do not disturb otters, if the otters are familiar and comfortable
with their caretakers, and if parental care and cub development, behavior, and health is
monitored in a way that does not cause disturbance to the otters. (See Chapter 2 for more
information on these issues.) Also litter births that are not detected, but they are suspected, false
pregnancies, and estrus cycles should also be closely monitored and evaluated. (Section 4
below lists other reproductive characteristics that should be recorded and studied.)
Detailed records on the aforementioned issues should be recorded, studied, and openly shared
by every institution holding a potential breeding or breeding pair, unfortunately they are often
not. These records should be compiled and scientifically studied so that husbandry and
management recommendations can be further updated and expanded upon. The international
studbook is needed to help encourage all holding institutions to achieve these goals.
Observations of wild giant otters in Peru:
“Only half of the cubs survived the first year: Out of 31 cubs that were identified
by their throat pattern, 16 (51.6 %) disappeared during their first year of life.
Because of their dependence to the mother [i.e. for nursing] and the fact that only
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