Abstract

Captive polar bears may exhibit behavioral abnormalities. While some appear to adapt to captive situations, others may develop obvious behavioral issues or coping mechanisms. Studies indicate species of bear with the largest territories are most likely to exhibit stereotypies in captivity (Club 2007). Medical or dental problems, reproductive frustration, or boredom from a lack of stimulation may also lead to the development of stereotypic behaviors. Bears with stereotypies should receive physical examinations and appropriate veterinary medical work-ups because stereotypies may be caused or exacerbated by chronic or painful conditions.

Animal Welfare Regulations Specific to Polar Bears

Subpart E of the Animal Welfare Act has regulations specific to marine mammals. Regulations specific to polar bears are found in §3.104 (e). They state: primary enclosures must have a pool of water, a dry resting and social interaction area, and a den. The dry resting and social activity must be a minimum of 37.16 m² (400 ft²) for up to two polar bears, with an additional 3.72 m² (40 ft²) for each additional polar bear. There must be enough shade to accommodate all polar bears housed in the primary enclosure at the same time. The pool must have a minimum horizontal dimension (MHD) of at least 2.44 m (8.0 ft), a minimum surface area of 8.93 m² (96 ft²), and a minimum depth of 1.52 m (5.0 ft). For each additional bear the surface area of the pool must be increased by 3.72 m² (40 ft²). Parts of the pool that do not meet the minimum depth cannot be included in the calculation of the surface area. The den must be a minimum of 1.83 m (6.0 ft) in both width and depth, and at least 1.52 m (5.0 ft) in height, and positioned so the viewing public will not be visible to the bears from the interior of the den. A separate den must be available for each adult female of breeding age permanently housed in the same enclosure as an adult male. Female bears in travelling acts or shows must be provided a den when pregnancy has been determined.

Enrichment and Use of Space

Providing adequate space for polar bears not only gives them more incentive to exercise, but may help to prevent stereotypies. Bears may also be encouraged to explore and increase their daily activity when food incentives or other positive reinforcements are introduced into their environment. Training animals to move from one area to another promotes exercise and may help to prevent or extinguish repetitive behaviors. Polar bear enrichment may include offering indestructible toys, plastic floating drums, balls, puzzle feeders or placing food frozen into blocks or new scents into their environment. Training sessions may also be considered enrichment.

Substrate

Substrate composition is an important consideration for bears. Housing them on natural substrates such as grass, dirt, or sand, or using wood or supple engineered floors is preferable to concrete. Strategically placing substrates that yield to weight in areas where bears spend time or pace may help to prevent arthritis or other injuries.

* Presenting author

Literature Cited

1.  Club R, Mason GJ. Natural behavioural biology as a risk factor in carnivore welfare: How analysing species differences could help zoos improve enclosures Applied Animal Behaviour Science. 102(2007):303–328.