Color Vision in Sika Deer (Cervus nippon): Color Discrimination between Three Colors (Red, Green, and Blue) and Gray

Abstract

We investigated the ability of two sika deer (Cervus nippon nippon) to discriminate between three primary colors (red, green, and blue) and gray under light and dark conditions (Experiment 1 and Experiment 2) using a T-maze technique. The light intensity in the center of a stimulus color card in Experiment 1 was 200lux and that in the Experiment 2 was 0.1lux. One session consisted of 20 trials. The criterion of successful color discrimination was 16 or more correct choices out of 20 trials for 3 sessions in a row (P < 0.01 by Chi-square test). Experiment 1: Both sika deer fulfilled the criterion in the 4th, 3rd, and 3rd sessions in the discrimination test between green and gray, red and gray, and blue and gray. Experiment 2: In each of the green vs. gray and blue vs. gray discrimination tests, two sika deer fulfilled the criterion by the 3rd session. The correct responses of two sika deer fulfilled the criterion within the 6th session in the discrimination test between red and gray. In conclusion, sika deer did have a high ability for discrimination between the three primary colors (red, green, and blue) and gray under light-dark conditions, thereby valuable information for the development of effective methods for preventing deer invasion was obtained.