Habitat selection during dispersal reduces the energetic cost of transport when making large displacements

TL;DR

Animals dispersing over long distances save energy by choosing open habitats like roads for movement.

Contribution

The study reveals that habitat selection during dispersal significantly reduces energetic costs of transport.

Findings

Dispersing vulturine guineafowl prefer open habitats and roads for movement.

Using roads reduces energetic costs of transport by over 33% compared to other habitats.

Abstract

Dispersal is energetically costly. However, there is now growing evidence that dispersing animals can express distinct movement strategies that allow them to mitigate most of the energetic costs of displacing over large distances. While to date we know that these strategies involve changes in how dispersing animals move, it is unclear whether these changes in movement are facilitated by other components of behaviour—namely changes in habitat selection. Here, we collected high-resolution GPS tracking data in terrestrially dispersing vulturine guineafowl (Acryllium vulturinum) to test the hypothesis that dispersing animals should select for habitats that facilitate more energetically efficient movements during dispersal. Using step selection analyses, we find that actively dispersing individuals exhibit increased positive selection for open habitats, especially roads. We then use models of the energetic costs of movement to show that moving along roads facilitates straighter, faster movements and results in a more than 33% reduction in the energetic cost of transport relative to other habitat types. Our results confirm that fine-scale differences in habitat selection expressed by dispersers facilitate more energetically efficient movement, expanding our understanding of how animals exhibit adaptive movement strategies across different axes of decision-making (e.g. where and how to move) to overcome ecological challenges.

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