Preferences of Orange-winged Amazon parrots (Amazona amazonica) for cage enrichment devices Lilian C. Kim, Joseph P. Garner 1 , James R. Millam * Department of Animal Science, University of California, One Shields Avenue, Davis, CA 95616, United States 1. Introduction Since the implementation of the Animal Welfare Act in 1966 and several times since, legislation has been enacted in a continuing attempt to improve the quality of care for animals kept by humans for commercial, research, and other purposes. With an increased interest in the psychological health of animals and the potential of stress and suffering to compromise the integrity of scientific research using animals, additional considerations continue to be evaluated to better understand the impact of environmental enrichment on animal well-being. Supplementation of a captive animal’s surroundings with environmental enrichment is aimed at promoting Applied Animal Behaviour Science 120 (2009) 216–223 ARTICLE INFO Article history: Accepted 15 June 2009 Available online 10 July 2009 Keywords: Parrots Environmental enrichment Preference testing ABSTRACT Cage enrichment devices (ED), frequently termed cage ‘‘toys,’’ are often provided to captive parrots as a means of promoting a behaviorally stimulating environment, but it is not clear whether particular properties of EDs are more effective than others in eliciting engagement with them. We tested preference for color, size and hardness of cube-shaped EDs constructed from wood and of color preference for EDs constructed from flat rawhide rectangles. Orange-winged Amazon parrots (Amazona amazonica; N = 8–10, mixed-sex, 4– 5 years of age) were individually housed in cages each equipped with two computer- monitored omni-directional lever-type switches attached to cage ceilings. EDs were attached to the switches; any interactions generating lateral movement and causing switch closure (operationally constituting ‘‘use’’ of EDs) were continuously recorded. Preference for 3.8 cm 3 softwood (Douglas fir) cubes dyed in eight different colors was tested by presenting each bird with all combinations of colors, two colors at a time. Daily switch activity averages were computed for each bird and subjected to repeated-measures ANOVA: yellow cubes elicited greater use than red, green, blue, violet or natural cubes (P < 0.05; but see below) and orange cubes were preferred over green and blue cubes (P < 0.05). Color exerted no effect in a comparable trial of rawhide rectangles. Preference for size of yellow hardwood cubes was tested by presenting combinations of cubes of three sizes: 2.5, 3.8, and 5.1 cm 3 ; the smallest blocks were preferred over the largest size (P < 0.001). Preference for hardness of wood was tested by presenting birds with 3.8 cm 3 yellow cubes and blue cubes made of either Douglas fir (‘‘soft’’) or birch/maple (‘‘hard’’) wood; birds preferred softer cubes (P < 0.0002), but there was no significant preference of yellow over blue. The results show that color, hardness, size and material all influence ED use by captive Amazon parrots. This constellation of preferences may reflect properties of foods native to Orange-winged Amazon natural habitat. Published by Elsevier B.V. * Corresponding author. Tel.: +1 530 752 1149; fax: +1 530 752 4498. E-mail address: jrmillam@ucdavis.edu (J.R. Millam). 1 Present address: Department of Animal Sciences, Purdue University, 915 W. State St., West Lafayette, IN 47907, United States. Contents lists available at ScienceDirect Applied Animal Behaviour Science journal homepage: www.elsevier.com/locate/applanim 0168-1591/$ – see front matter . Published by Elsevier B.V. doi:10.1016/j.applanim.2009.06.006