Only few animals have a permanent home which they use throughout the year. The great majority only has one during the breeding season for protection of the young. In spite of this, given the opportunity, any rat, independent of sex and age, makes a multi-purpose nest and resorts to it for habitation, cover, sleeping, breeding and sometimes, as a feeding place. Maternal nest building seems to represent an autonomous process. The black rat (Rattus rattus) has a widespread distribution throughout the world. It is well-suited for arboreal life and is omnivorous with a preference for plant matter. Its behavioral flexibility is also displayed in its versatile nesting behavior. Given the rat’s negative geotaxis drive and its notable climbing ability their nests are mostly "areal". In spite of this, it has been found that rats nest underground, on the ground and as a commensal dwelling in man-made buildings. More than that, sympatric rat populations which share a common niche with identical ecological conditions differ in their nest-building behavior. The nest-building flexibility is exhibited in the nest location, its shape, structure, size, building material, etc.

Previous extensive study in pine-tree habitat and experimentally manipulating rats’ environment by means of man-made semi-artificial conditions, enable a comparison with several studies on rats’ nesting behavior in diverse habitats throughout the world. This goal may be achieved by tracking with updated methodological and technical means, the nesting behavior of reciprocally interchanged rats which display a given specific building behavior habitat, to a habitat where rats nest in a different way. This work may provide an important contribution in clarifying the factors involved in different aspects of the versatility of the rat nest-building behavior.

References

1. Aisner, R.; Terkel, J. (1991). Sympatric Black Rat (Rattus rattus) populations: different food handling techniques. Mammalia, 55 (2), 307-309.
2. Aisner, R.; Terkel, J. (1992). Ontogeny of the pine opening behavior in the Black Rat (Rattus rattus). Animal Behaviour, 44, 327-336.
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