International Giant Otter Studbook Husbandry and Management

informal international network has been established to help achieve all of the aforementioned
goals. Already, progress has been made to help reduce some of the problems of giant otters in
captivity. For example, on an international level there has been increased communication,
information sharing, interest in working together, and research, and improved cub-rearing
success and transfer/exchange of otters as well as improvement in enclosure conditions.
Because of the contributions, research, and shared experiences of the institutions world-wide
and historically that have held giant otters and those who have studied this species in the wild,
the formation of the studbook and husbandry and management guidelines for giant otters in
captivity have been possible. Summaries and details of this collected information are presented
throughout this manual and the guidelines are based on this information. This although is only
a beginning as much more progress is needed to achieve all of the necessary goals. (It would be
beneficial if the studbook and husbandry and management recommendations could be available
in multiple languages. Efforts will be made to accomplish this within future editions.)
Section 1
Census Data and Number of Potential Breeding Pairs
Historically, international census data show small populations of P. brasiliensis in captivity.
Many zoos currently hold giant otters singly or in single sex groups or are in need of unrelated
animals to prevent further inbreeding. There is little interest, communication, and cooperation
among many institutions holding this species to pair individuals to increase the number of
potential breeding pairs and reduce inbreeding (Sykes-Gatz 2001). Because few zoos have
exchanged giant otters across, or even within, international boundaries, a significant number of
mature individuals are held in non-breeding situations in this small population. The majority of
these individuals are held singly without any partner. Giant otters are social animals that mate
for life and live in family groups, therefore keeping them singly for an extended period of time
may cause mental / behavioral health problems. These health problems may also negatively
affect future pairing and breeding success. Limited complete data regarding world-wide age
distribution, genetic relationships, and census/birth/death records exists, therefore appropriate
sound groupings and regroupings will be more difficult to make with the current records. Much
of the information needed to complete this data is not published, recorded, or shared by/among
many institutions.
Current international census data revealed that between 2002 and September 30, 2003
approximately 27 institutions in 10 countries (7 countries in South America) reported holding 58
otters (30.28) (Sykes-Gatz and Gatz unpublished report). (Census only includes individuals
one year old or older and the institution’s census during the most recent year reported. The total
population therefore refers to all animals one year old or older. See census Tables 4-5.)
Between 2002 and 2003, 37% of the total number of institutions (10 institutions) held at least
one potential breeding pair. Of the captive population of animals that are 2 years old or older,
51 % (or 12.13* individuals) are paired in a potential breeding situation. Note: Cuiaba Zoo
holds one male paired with two females. Currently, of the number of animals who are in
potential breeding pairs, only four of these pairs (or 31 % of the potential breeding pairs) are
producing offspring. Of these four pairs, 3 are rearing their litters successfully (i.e. at least one
cub in the litter lives to one year or older). Inherited thyroid malfunctions due to severe
inbreeding were likely to have prevented the survival of all of the cubs born at fourth
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