Plasticity in resource choice: a time-limited butterfly prioritizes apparency over quality

Animals often plastically adjust resource choice to improve search efficiency or access to high-quality resources. However, animals may encounter environments in which resources vary in both apparency and quality, making it difficult to simultaneously search efficiently and exploit high-quality resources. We tested the hypothesis that time-limited animals tend to prioritize resource apparency, sometimes over resource quality. We observed individual cabbage white butterflies, Pieris rapae, as they searched for visually discriminable host plants (cabbage) and host plants that closely matched nonhost plants in our arena (radish). We found that cabbage was more discriminable than radish due to a waxy ultraviolet (UV)-reflective layer which, when removed, decreased butterfly search accuracy. When cabbage (with wax) and radish were both of high quality, butterflies preferentially landed on cabbage, despite radish being a superior resource in terms of growth rate. When differential fertilizer application was used to lower cabbage's quality relative to radish, butterflies slightly reduced their landings on cabbage compared to other treatments but still showed a preference for cabbage (the more discriminable host). Furthermore, individuals with more pronounced preferences for the discriminable host made fewer mistakes during host searching. These results suggest that while resource choice is sensitive to changes in host quality, time-limited species continue to visit relatively more discriminable resources even when they are of low quality. We argue that an understanding of species ecology gives insights into when animals may fail to plastically adjust decision making.(c) 2022 The Association for the Study of Animal Behaviour. Published by Elsevier Ltd. All rights reserved.