International Giant Otter Studbook Husbandry and Management

animal was captive-born at Hagenbeck Tierpark and was held at Dortmund Zoo. (Osmann,
pers. comm. 1993)
At Hagenbeck Tierpark, it is reported that by 6 ½ months of age the captive-born giant otter has
grown to 2/3 of the adult size (Hagenbeck & Wünnemann 1992).
Sexual Maturity in Captivity:
Field biologists and institutions that hold giant otters in captivity are in need of accurate
information regarding the earliest age of sexual maturity (i.e. mating) for both females and
males, in both the wild and in captivity. The earliest age of sexual maturity is not known, only
estimated, in the wild, and in captivity the earliest age of sexual maturity is also not clear. As
well, field researchers are interested to know the earliest age of siring/bearing litters both in
captivity and in the wild. More detailed records needed to be maintained, shared and studied at
zoos world-wide to find clear answers to these questions.
Wünnemann (1995 b ; Hagenbeck & Wünnemann 1992) stated that giant otters (both sexes) at
Hagenbeck Tierpark reached sexual maturity and mated successfully at about 2 years old. This
is accurate for their male, as he first mated (and sired a litter from this mating) at about 2 ½
years old. Although the breeding female (Ottilie) that they used to make this determination, was
not 2 years old, but rather 4 years old when she gave birth to her first litter. (This was
discovered from Brasilia Zoo records by Louzada da Silva [pers. comm.]. This fact was
unfortunately not discovered until long after Hagenbeck published their articles/studies).
Although, because the age of the other females who bred at this facility were only estimated,
accurate age of sexual maturity for them is not clearly known. Unfortunately, in this case
Wünnemann’s (1992) information, that giant otters “reach sexual maturity at an age of about 2
years” at his institution, can not be considered accurate for the females.
At Dortmund Zoo, a female first mated at 2 years and 10 months old, became pregnant from this
mating and gave birth to her first litter at 3 years old. The sire was her brother, but the mother
and the father were from different litters and they were not paired together until after the male
had reached sexual maturity. This female’s mate was 4.5 to 5 years old when he first mated and
sired this litter (Gatz pers. comm.). This pair was housed together 2 years before their first
mating. Unfortunately, it is not known if there were previous matings before this date. So, it is
not known with 100% accuracy at this zoo when the female reached sexual maturity.
In summary, it can be said that at 2 years and 10 months old females can come into estrus, mate,
and bear litters at 3 years old. A male can mate at 2.5 years old and sire a litter at 2 years and 8
months old. Although, because of the limited records, it is not known if this is the earliest age at
which giant otters can become sexually mature. These records are the only accurate and
complete records that are known at this time.
Section 2
Reports of Cub Development and Parental Behavior in the Wild:
Two emaciated and moribund cubs at approx. 6 weeks of age at the Paramaribo Zoo weighed
and measured the following (Duplaix 1980). The male weighed 1400 g [49 oz] and measured a
total length of 55 cm [21.7"]. The female weighed 1200g [42 oz] and measured a total length of
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