Repeatable colour preferences predict information use in nest-building birds.

More than a century ago, naturalist Henry Smith Williams observed that birds nesting in his garden differed in their colour preferences for nest-building materials. His observations challenge the assumption that individuals within the same species respond similarly to the same colour cues, but the stability and consequences of these apparent preferences remain largely unexplored. Here, we tested the colour preferences of laboratory-raised zebra finches (Taeniopygia guttata) with access to pink and orange nest-building string. Birds were tested under conditions lacking relevant environmental cues, social information, or previous experience with the experimental colours. Individuals differed in both their preferred colour and the strength of preferences, which were more strongly repeatable across short-term than long-term intervals. We next asked whether these stable individual preferences influenced how birds respond to information, reanalyzing published social-learning datasets spanning different informational contexts. Stronger initial preferences generally predicted reduced use of socially demonstrated nonpreferred colours during nest building. These findings suggest that stable individual preferences represent an underappreciated source of variation in how animals acquire and use information during decision making.