International Giant Otter Studbook Husbandry and Management

with a male (other than growing up with their father) before their current pairings. All of the
females are now (at the end of this report) around 3 ½ years old. (None of the males have ever
sired litters or been paired with a female partner before their current partner. Two males are 11
½ years old and one male is 4 ½ years old. ) Further research should be carried out and a worldwide
survey should be conducted on these matters. It should be determined if there is a trend in
these occurrences and what the causes may be.
Gestation, False Pregnancies, Signs of Parturition, Reproductive Capabilities at Late Age,
Litter Births and Initial Care:
Gestation usually occurs from 65 to 70 days in captivity (Hagenbeck and Wünnemann 1992;
Wünnemann 1995, Trebbau 1978; Autuori & Deutsch 1977). Wünnemann reports that
gestation also occurred from 64 to 71 days (Wünnemann 1995 b ). Gestation was reported to
occur for 77 days (Gatz, pers. comm.) (This happened twice with one captive female and
gestation was counted from the last day of mating seen. See below.)
False pregnancy reports are not uncommon. A significant number of zoos have reported this
occurrence. Giant otters can become enlarged in the abdominal area and develop
swollen/extended teats during false pregnancies and they, upon this physical condition alone,
appear as if they are pregnant. It is very difficult from visual observations alone to tell if the
animal is actually pregnant. The swelling usually disappears within a few weeks and no
evidence of litter birth is found. (Cubs are not heard, seen, and no remains of cubs are found
within the parents’ feces or enclosure.) For example, at Sao Paulo Zoo, “Signs of pregnancy
were visible on 2 females (swelling of the abdomen and enlarging of the mammillae) but in both
cases the animals got back to their normal state after a few weeks.” (Autuori & Deutsch 1977).
Three false pregnancies, in one female, were confirmed by ultrasound via husbandry training at
Dortmund Zoo. These occurrences should be more thoroughly studied to determine why they
are occurring at this frequency and what is causing them to occur. See Chapter 1 Section 4 and
Chapter 3 for ultrasounding to detect pregnancy and why pregnancy detection is so important.
“The gestation period is from 65-70 days. One month before parturition the swelling of the teats
became visible and about 14 days before parturition we could see the swelling of the vulva. We
could see no signs indicative of imminent parturition on the day of birth and indeed Ottilie took
food just six hours before the birth of her last two litters. Shortly before the births of the litters
in 1988 and 1989, Ottilie had ‘adopted’ herrings, taking them carefully between her powerful
jaws and placing them near her teats. This apparently maternal behavior, however, did not
inhibit her from eating the fish some hours later. We saw no sign of the behavior being repeated
before the later successful liters….The birth took place in the “early hours of the morning”.
“The first pup was delivered at 0100 hours, the second was stillborn at 0200 and the last two
births followed at 0215 and 0230 hours. The mother extracted the pups with her mouth, licked
the young, picked them up in her mouth to shake them gently and placed them on the teats.
After this initial care, the pups received no further help from the dam and always had to reach
the teats by themselves.” (Hagenbeck & Wünnemann 1992).
In addition this female at Hagenbeck Tierpark, gave birth to 10 litters in 4 years and 5 months
(i.e. averaging 2 litters per year and in one case 3 litters in nearly almost one year i.e. 11 days
short of one year) (Hagenbeck & Wünnemann 1992; Flügger 1997). For example, their female
“…once again had cubs [11-1-92], although she was still raising adolescents….On 2-2-94
Ottilie once again gave birth to 5 pups even though she was still raising one youth.” Flügger
1997). Their only successful breeding female, at 11 years old, developed pyometra during her
215