International Giant Otter Studbook Husbandry and Management

that the otters are very familiar and comfortable with the caretaker during this period to lessen
disturbance/stress (Hagenbeck & Wünnemann 1992; Flügger 1997). (See Chapter 2-3 for more
information).
Husbandry training should also be carried out to increase knowledge. Many details about giant
otter behavior, physical characteristics, and biology (esp. reproduction & physiology) are still
unknown and much research needs to be conducted. (See Part B above and below for aspects
that should be studied.) Such information is needed as a reference source for giant otters in the
wild, as well as for comparison studies in captivity. Otters should not be anesthetized and no
other potentially stressful, harmful, or dangerous methods (to both otters and staff) should be
used for the specific and sole purpose of gathering such information. When otters are trained to
allow procedures to be conducted for research, information can be easily and safely gathered
without stress or harm to the otters or staff and studies can be conducted to help conservation
efforts in the wild and help better manage giant otters in captivity. The otters will also have an
enriching experience.
For example, field biologists have recently requested information on adult body length and
corresponding weights and sexes for comparison to giant otters in the wild. Measurements
should only be done through husbandry training or when the otter has been anesthetized for
another reason (i.e. medical emergency etc.). Milk samples that normally could not be drawn
(without stressful or dangerous methods) may be drawn from lactating females only after litter
loss and via operant conditioning. (See Section 5 below and Chapter 5 on why giant otter milk
sampling is important and Part B above for taking adult measurements.) Additionally, during
anesthesia some physiological values, such as normal resting heart and respiration rate and body
temperature, will change so true values can only be reported via training (see below).
Examples of husbandry training and procedures, specific physiological values drawn, and
specific biological information that is needed for study/comparisons are discussed below. Much
of this information has never been gathered before and it is highly recommended that other zoos
carry out such training so that scientific knowledge can be increased and comparisons can be
made with other otters. When cubs are handreared this information should also be gathered.
A female giant otter at Dortmund Zoo has been husbandry trained to allow ultrasounds to be
conducted on her, via portable ultrasound. From what is known, Dortmund was the first and
only zoo to conduct ultrasounds on giant otters in this manner (i.e. when otters are not under
anesthesia and via training). Ultrasounds are used at this institution to detect giant otter
pregnancies well before birth and to determine health status and health problems (i.e. uterine
condition) related to reproduction. Several ultrasounds were conducted during gestation up
until one week before this mother gave birth. Fetuses and uterine condition were observed
during the ultrasounds. The female aborted decomposing fetus parts 4 to 5 hours before the
birth of live born cubs and missed several following estrus cycles, which indicated that she may
be slowing down/ending in her reproductive capabilities and/or may experience health problems
during future pregnancies. (See more information under Chapter 4.) It is suspected that either
her late age or great number of litters, or both, are responsible for these problems. The size and
condition of the female’s uterus was also monitored by ultrasound one time per week for several
weeks after litter loss (which was soon after birth) and once every two weeks thereafter. Staff
wanted to be sure that the cub which was aborted in a decomposed state, did not infect the
mother’s uterus and that no cub parts were left within her uterus. (Antibiotics were also
administered as a precaution.) Because normal uterine size is not yet known, no comparisons
with other females could be made to determine if this female’s uterus decreased in size at a
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