International Giant Otter Studbook Husbandry and Management

Section 12
Natural Underground Dens, Hills/Banks, Varied Terrain, Flat Land, Steep
Banks/Hills, Ramps & Stairs
Observations of wild giant otter territories and underground dens in Suriname:
“The size of the home range can only be roughly estimated…[it] is roughly 12 km
long and 12 km wide…Normally a pair of otters and their offspring of the past
two years will clear and mark sites dotted along a 2 to 3 km section of the creek,
even though they may wander over these borders at regular intervals…At least a
portion if not all the territory is patrolled each day…They excavated or renovated
five new dens when they settled in this new portion of their home range, using
eight different dens in two months….
…. It was possible to measure the tunnels and den chambers of 3 dens. The tunnel
measuring 30 cm to 3.6 m in length leads up to the oval chamber which measures
1.2 m to 1.8 m in diameter and is 43 cm - 74 cm high. No bedding material was
found inside, only a bare sandy floor worn smooth…A small air hole 10-20 cm in
diameter may be present if the overhanging tangle of roots in the roof does not
offer sufficient ventilation. While the chamber floor is level, the tunnels leading to
it may turn upwards or sideways at an angle of 35°-45°….The average size of the
30 den entrances which could be measured were 52.5 cm wide and 37.4 cm high.
…The den consists of a tunnel leading to a single chamber which has been
excavated into the riverbank….The diameter of the tunnel opening is consistent
with the approximate diameter of an adult otter in a crawling position,
approximately 30-40 cm in diameter. Tunnel openings may partially cave in in
looser sandy soils until they are quite wide, up to 1.50 m.
Upper Coesewijne river
(5 dens, 13 holes)
Kabo creek
(Tibiti river)
(8 dens, 8 holes)
Kaboeri creek
(Jan-Sept 1977)
(8 dens, 14 holes)
39.77 cm (width)
range = 18-80 cm
47.88 cm (width)
range = 30-100 cm
57.14 cm (width)
range = 32-150 cm
32.23 cm (height)
range = 18-60 cm
32.13 cm (height)
range = 20-42 cm
39.86 cm (height)
range = 27-55 cm”
The large variation between maximum and minimum sizes represent the difference
between new den entrances (minimal size) and older dens (maximum size)... While
sandy soils cave in more often they are still used and the dens [den] is repaired
until it is abandoned.” (Duplaix 1980).
“High forest usually meant high banks with relatively little undergrowth and the
otters preferred lower lying areas...The key factors in habitat choice are…low
sloping banks with good cover…” (Duplaix 1980).
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