Assessing choice ability and preferences of five Leopard Tortoises (Stigmochelys pardalis) for three stimuli through a novel two-phase preference test

Abstract

Preference testing has long been used in ethology and animal welfare science to assess the preferences that animals have for different resources and stimuli. The study conducted herein assessed the choice-making ability of five leopard tortoises Stigmochelys pardalis in a novel two-phase preference test. Phase 1 was a discrete choice test in a y-maze with two options: food in one arm, the other arm left empty, with positions fixed per tortoise, but randomised across tortoises. Multivariate ANOVA were performed on three dependent variables of time taken to make a choice in both phases. In Phase 1, four of the five tortoises clearly chose the food arm more than the empty arm. One tortoise chose the food arm and empty arm equally (50/50). Phase 2 involved opening an additional arm on the maze and offering each tortoise three choices: food (the same as Phase 1); human interaction (shell scratches and rubs using hands); or an empty arm. Positions were again fixed per tortoise but randomised across tortoises. In Phase 2, tortoise choices were more varied. Two tortoises chose human interaction more than the other two maze arms; another two chose the food maze arm most; and one did not seem to show a strong preference for any particular arm. These results suggested that some individuals of this species of tortoise may possibly prefer this form of human interaction (shell scratches and rubs) over other stimuli in certain conditions; however, further research is necessary to improve the confidence of the conclusions presented herein.