@article{
author = "Golubovic, Ana and Anđelković, Marko and Arsovski, Dragan and Vujovic, Ana and Ikovic, Vuk and Djordjevic, Sonja and Tomovic, Ljiljana",
year = "2014",
abstract = "Dense vegetation cover undoubtedly offers certain advantages for small
and slow-moving animals, but its disadvantages concerning some aspects
of spatial ecology (e.g. movements) were neglected in previous studies.
Tortoises could get stuck in vegetation by protuberant part of the shell
and thus succumb to overheating, dehydration or predators. To examine
how vegetation cover shapes behavioural responses of `trapped'
tortoises, we tested adults of six populations from habitats with
contrasting vegetation cover. The tortoises were fitted with a
non-stretchable rope, representing a piece of vegetation, stuck on the
protruding front part of the plastron. Results suggested the existence
of two distinct releasing techniques. First, and only successful in this
study, is frequent changing of the movement direction, with a minimal
pulling force, until the obstacle detached. The other involved the
maximal pulling force aimed at ripping out the constraint. Tortoises
from shrub habitats had more releasing success, used less pulling force
and needed shorter time period to release, contrary to tortoises from
herbaceous habitats. Although sexes showed similar releasing success,
females obtained lower number of direction changes and higher yanking
force compared to males, suggesting slightly different liberating
strategies between the sexes. For immobilized tortoises without suitable
shelter from overheating and dehydration, appropriate behavioural
response could be vital, especially during drought years, due to
increased physiological stresses. Variability of behavioural patterns
among tortoise populations, described in this study, could have an
adaptive significance.",
journal = "Acta Ethologica",
title = "Skills or strength-how tortoises cope with dense vegetation?",
number = "3",
volume = "17",
doi = "10.1007/s10211-013-0171-3",
pages = "141-147"
}