International Giant Otter Studbook Husbandry and Management

described below and in Section 12 below.) The stress caused by human disturbances and
presence has resulted in the loss of a critically significant number of giant otter cubs.
Historically and internationally (from 1968-2002), records show that most of the captive-born
giant otter cub deaths reported (where full cub history was known), died because parents,
stressed by disturbances, failed to properly care for their cubs. No institution has ever reared
their giant otter cubs successfully unless privacy was offered during cub-rearing. Even
parents that had already reared one or more litters successfully with seclusion, did not
rear their following litters successfully unless they were offered this method. (I.e. without
this method they ate or neglected their cubs and litter loss resulted because of disturbances to
the parents.) See Chapter 1 for more information about these issues.
Observations of wild giant otters in Peru:
“Giant otters are highly susceptible to disturbances [esp. during cubrearing]….The
reason for the minimal reproductive success of the Cocha
Salvador group and the birth of a litter outside of the normal season can be
related to human disturbances.” (Translation from Staib 2002). In the wild giant
otters are more nervous when they have cubs. They are also nervous when
anything unusual occurs in their environment, this includes the presence of
humans (Schenck 1996; Schenck et al 2003).
Baker et al. (1996) reviewed evidence from mammals that psychological stress, particularly for
Carnivora, to the parents is often responsible for the parents’ failure to rear litters successfully.
After giving birth, captive carnivore parents can be especially vulnerable to disturbances
and normal human activity, which did not bother them before parturition. At the time of
parturition and during cub-rearing, stress to the parents can be caused by human
disturbances (visual and acoustic) and presence (visitors and zoos staff) or any changes to
the parents’ “social” or “physical environment”.
The following behaviors, caused because giant otter parents were stressed by disturbance, have
been reported to occur during cub-rearing (Autuori & Deutsch 1977; Hagenbeck & Wünnemann
1992; Gatz, pers. obs. 1996-2002; Flügger 1997 & pers. comm.; Sykes 1998/2002; Sykes-Gatz
2001, unpublished reports 1999-2003 & pers. obs). Parents physically abused, i.e. bit, injured,
threw, slammed around, nearly drowned, rolled and laid on, suffocated to death by laying on,
or/and ate their cubs. They also failed to properly care for and neglected or excessively
handled their cubs in other ways. They repeatedly carried their cubs around the enclosure
or moved them from one nestbox or place to another within a short time period or performed
these actions too many times or even excessively throughout the day. (Note: this indicates that
the parents are uncomfortable and they do not feel that their cubs are safe in a particular area, so
they move their cubs in attempts to find a safer feeling place. It is also simply just a reaction to
stress.) They also excessively moved, pushed, slammed around, handled, and toileted their
cubs. Mothers’ were suspected to have failed to lactate sufficient amounts of milk due to
stress and they were observed to press their bodies flat to the ground as a reaction to stress,
so that the cubs could not nurse sufficiently during those times. When parents became
nervous in behavior, because of a disturbance, they did not lie still long enough so that the
cubs could nurse or the mother left the cubs unattended for too long. (E.g. the cubs were
crying because they were hungry or felt alone and the mother did not return to nurse or pay
attention to them frequently enough.) During these times, the cubs had little or no chance to
nurse. [Very young giant otter cubs, from birth to at least 7 days old when the remaining cub
was pulled for handrearing, nursed frequently during each hour of the day (Sykes-Gatz, pers.
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