International Giant Otter Studbook Husbandry and Management

When nestboxes are dimly lit, cubs have fallen asleep on the mother’s teat (which was often), or
when parents or other siblings are covering the nursing cubs (so they cannot be seen) the
aforementioned behaviors are important to help determine when cubs are actually nursing.
(Note: parents with cubs must be isolated from all human disturbances during cub-rearing.)
When the giant otter cubs were crying more often than usual, this indicated that they were
hungry, feeling neglected, being abused, or feeling sick. Developing cubs (at Dortmund Zoo),
that were observed until they were at least 2 ½ months old, were also observed to nurse very
frequently throughout the day and/or hour depending on age. The behavior of these cubs was
monitored when the cubs/parents were visible in their enclosure and it was also monitored by
the vocalizations of the cubs and parents when they were in their nestboxes. All was monitored
from hidden/isolated viewing areas so that the parents did not detect the observer and they were
not disturbed (Sykes-Gatz unpublished report 1999-2002 and pers. obs.).
Immediately after the 7 day old giant otter cub at Dortmund Zoo was removed from its parents
for handrearing, it eliminated softly formed dark green stools (Sykes-Gatz, pers. obs.
unpublished reports 1999-2002). This stool resulted from mother’s milk, although it is
important to note that this cub died of an inherited thyroid malfunction at 11 days old, which
may have affected its stool color. The cub although did not appear underweight at the time it
was pulled, but it was significantly injured from a bite wound that one of the parents inflicted.
At Hagenbeck Tierpark, “The female has four mammae. In the first days of life the cubs tend to
fall asleep when suckling, keeping the teat in their mouth for hours.” (Wünnemann 1995 b )
(Nursing frequency and length should be monitored and thoroughly documented for cubs during
their entire development, but only when the observer does not disturb parents. This is necessary
for comparisons to other cubs, both in the wild and in captivity, and for handrearers to help
provide feeding schedules more closely related to the cubs natural nursing behavior.)
Eyes First Open:
The cubs’ eyes opened at 30 days old at Sao Paulo Zoo (Autuori & Deutsch 1977).
At Hagenbeck Tierpark the cubs’ eyes opened at 6 weeks old (Hagenbeck & Wünnemann
1992).
At Dortmund Zoo the cubs’ eyes first opened at 30 days old (Gatz & Sykes-Gatz pers. obs.).
Leaving/Entering the Nestbox:
“Giant otters will use a number of nest boxes and like to change several times while rearing
their offspring.” (Wünnemann 1995). When the female reared her cubs alone, Hagenbeck
reports “The female changed nestboxes with her litter several times, carrying the young in her
mouth.” (Hagenbeck & Wünnemann 1992). Hagenbeck Tierpark reports, “At 67 days of age
they left the nestbox and were seen entering the water for the first time.” (Hagenbeck &
Wünnemann 1992).
At Sao Paulo Zoo, “The female [mother] leaves the shelter several times a day – 3 to 5—and
gets into the water to catch fish and eat them…” [After eating, she also spent time chasing and
killing fish that she did not eat].…..[At 63 days old] for the first time, the small ariranha was
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