International Giant Otter Studbook Husbandry and Management

difficulties/abnormalities involving their hind legs and lower back. Covering nearly the
entire enclosure land area with soft loose natural substrates (as recommended) seems to be
the most important husbandry provision needed to maintain healthy walking abilities.
This also seems to be the most important husbandry method needed to avoid or at least
significantly reduce the chance that the aforementioned health problems will occur or to
improve otter health if these problems have developed. This type of husbandry practice
alone can help otters that have developed these difficulties/abnormalities to a moderate and
even severe degree (because of the continual exposure to hard surfaces), to return to a very
significantly healthier or completely healthy state. Enclosures that do not provide enough
land area (i.e. because of inappropriate land to water ratios) or/and digging area may also
worsen or help to cause/predispose animals to the aforementioned problems. Appropriate
land to water area ratios (this is esp. critical in small enclosures) and sufficient digging area
sizes are therefore necessary as well. These findings were in part based on the following
studies.
Some giant otters that were kept, over a long period (i.e. 3 to 10 years), in enclosures that
were entirely or mostly composed of hard surfaces developed ongoing walking
difficulties/abnormalities involving their hind legs and lower back (Sykes-Gatz & Gatz
unpublished study). The hard surfaces were made of concrete, natural rock, or tile. These otters
were in their middle (e.g. around 4 years old) or late ages when they were observed to have these
problems and they were not observed/reported to have any ongoing walking
difficulties/abnormalities before they were housed in the aforementioned conditions. Before
they were housed on hard surfaces as described, they had access to enclosures where the
majority or all of the land area was covered with soft substrates and a sufficient amount of land
area and at least some or expansive digging areas were available. Sufficient swimming areas and
outdoor access, in temperate or South American climates, were available in every enclosure they
were housed in.
The aforementioned otters showed varying degrees of difficulty and abnormalities when
walking. The degrees ranged from moderate to severe. These included shuffling their hind
legs/feet rather than lifting them, walking very stiffly and/or abnormally, limping, showing
moderate difficulty when walking, or/and having great difficulty when walking. At least
one otter also exhibited abnormal walking in his front legs (i.e. walking very
stiffly/abnormally) as well as his hind legs. (Note: these animals displayed the aforementioned
problems continually throughout the day. Although additionally to these problems and after the
animal first rose from sleeping, the particular severity of its physical problem increased
significantly above the degree that it would display throughout the day. This degree of severity
would resolve shortly, e.g. within a few to several minutes or more after the animal first moved
about, and then the animal’s particular problem to the degree of severity as described above,
would resume.) Additionally, during observations, it was noted that one severely affected otter
(in his late age) exhibited difficulty when carrying out the physical actions necessary for mating
and he was unable to successfully penetrate his partner. The failure to breed was most likely, at
least to a significant degree, due to his aforementioned problems. I.e. the physical disorders
which were expressed by his walking difficulties affected his ability to mate successfully. He
sired no litters during the 8 months he was paired with his mate. (Previously and afterwards, his
partner had many litters with another male. Below are examples of how easy and inexpensive
enclosure modifications / furnishings can help to improve and maintain the giant otter’s physical
[as well as mental and behavioral] health.
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