Short-range homing in fiddler crabs (Ocypodidae, genus Uca): A homing mechanism not based on local visual landmarks

Citation
S. Cannicci et al., Short-range homing in fiddler crabs (Ocypodidae, genus Uca): A homing mechanism not based on local visual landmarks, ETHOLOGY, 105(10), 1999, pp. 867-880
Citations number
26
Categorie Soggetti
Animal Sciences","Neurosciences & Behavoir
Journal title
ETHOLOGY
ISSN journal
01791613 → ACNP
Volume
105
Issue
10
Year of publication
1999
Pages
867 - 880
Database
ISI
SICI code
0179-1613(199910)105:10<867:SHIFC(>2.0.ZU;2-0
Abstract
This field study investigated the spatial strategies and homing ability of two East African fiddler crabs, Uca lactea annulipes and Uca vocans hesperi ae, using various experimental procedures. A clear-cut spatial segregation between the two species was observed, with U. l. annulipes occupying areas even a few centimetres above U. v. hesperiae. Females of both species were extremely faithful to their holes while the males exhibited behavioural dif ferences. U. l. annulipes males were quite faithful to their holes; in cont rast, U. v. hesperiae males, during a single low tide, visited several hole s which they did not defend. Two displacement experiments were conducted in order to identify the stimuli that fiddler crabs use in their homing. In t he 'dislocation experiment', the crabs were moved (by hand) 1 or 2m away fr om their refuge and released. None of these crabs returned to its burrow an d, moreover, the initial directions they followed were not homeward orienta ted. In the 'translation experiment', the crabs were passively translated w hile actively feeding. When the crabs attempted to go 'home' after the tran slation, they darted along a straight path that led them to points that wou ld have corresponded to their homes if the translation had not taken place. After this first response crabs then commenced searching strategies that l ed half of them home. Short-range homing seems to depend strongly on inform ation actively gathered during the outward journey, other than local visual landmarks.