International Giant Otter Studbook Husbandry and Management

this study and it is believed that they will likely not reproduce again because of their old age.
Section 3B above describes how later on, this pair recovered from their mental and behavioral
health problems, because they continued to be kept in appropriate enclosure conditions after the
completion of the above study.
On the other hand, at Brasilia Zoo, where the exhibit and land area (nearly entirely covered
with soft loose natural soil) are expansive and many natural underground dens exist, parents
were not stressed by usual familiar activity that was somewhat limited. Many litters were reared
successfully at this zoo by several pairs of parents. This zoo has two 635m 2 (6,835.14ft²) seminatural
giant otter exhibits located directly adjacent to each other [i.e. only separated by a fence
containment barrier] which adds additional privacy from the public on one enclosure side. Each
exhibit has a 105 m 2 (1,130.22 ft²) pool and an 85% land to 15% water ratio. The extensive
hillsides that surround 2/3 of the exhibit’s land area perimeter also provide/provided ample area
for the parents to dig many natural underground dens (the top of the hills rise nearly to the
visitor level). Additionally, much of the land is located well below the visitor level. The
parents’ rear/reared their cubs in this enriched stimulating exhibit with underground dens
successfully. For example, the parents were not stressed, when the primary giant otter keeper
quickly and quietly entered the enclosure (with the otters present in the same enclosure) to dry
spot clean the feces and left over fish (Louzada da Silva, pers. comm. 1998; Brasilia Zoo, pers.
comm. 2002). The keeper left the enclosure immediately after this quick servicing. As well,
parents there also raised their cubs successfully when visitors had normal viewing access to the
exhibit, although for some litters a tall wooden barrier was purposely erected to restrict visitor
access and viewing. The design of this exhibit alone, i.e. expansive semi-natural exhibit and
land area size and natural underground dens, offers parents rearing cubs a great deal of privacy
and isolation from human disturbances. (The fact that the exhibit is well below visitor level also
contributed to privacy.) It as well offers parents an enriched stimulating environment (with not
only appropriate but optimal enclosure conditions) and this too is a very important factor that
contributes to the success of cub-rearing.
Part B.
Husbandry Practices and Enclosure Designs/Modifications for Cub-Rearing
The most important management practice needed to promote successful giant otter cub
rearing is the isolation of the parents from human disturbances (visual and acoustic) and
presence (zoo staff and visitors) during cub rearing. (Duplaix-Hall 1975; Autuori & Deutsch
1977; Hagenbeck & Wünnemann 1992; Wünnemann 1995; Flügger 1997; Sykes 1997-99 &
1998/2002, Sykes-Gatz 2001 & unpublished reports, 2003; “Genealogical Meeting…” 1998;
Louzada da Silva, pers. comm.; Corredor, unpublished report, 2003; Dortmund Zoo staff, pers.
comm..) This is the most important management factor responsible for successful parentrearing
of giant otter litters in zoos world-wide and historically (Sykes 1998/2002). The
success of parents rearing their cubs can also be intricately effected by and interrelated
with the quality, design, furnishings, size, and location of indoor and outdoor enclosures,
as well as husbandry and management practices. (See Parts A & C for more information on
other factors that can affect success.) 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
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