Social and Foraging Behavior in Northwestern Crows (Corvus caurinus): Incorporating New Analyses and Technology

Abstract

Both foraging and social decisions impact animals in important ways. We investigate the effects of age on foraging efficiency and sociality on Northwestern Crows (Corvus caurinus) at the beach, and use the growing field of social network analysis (SNA) to further examine social behavior in these birds. Specifically, we predict that 1) adults are more efficient foragers than juveniles, 2) juveniles interact with larger numbers of social partners than adults, 3) juveniles and adults prefer to associate with each other rather than within their own age classes, 4) crows are not associating randomly while on the beach (aka they have preferred social partners), and 5) pairs of individuals engaging in more affiliative behaviors with each other are less likely to also behave agonistically to one another, and vice versa. We also explore the uses of a remote radio detection system Encounternet by testing the validity of pilot data collected through this system against live observations conducted simultaneously. There is no effect of age on foraging efficiency; however, juveniles were found to interact with more total partners than adults, and most social associations occur between juveniles and adults. Our results also suggest crows are engaging in preferential social associations, though there is no evidence that affiliative pairs and agonistic pairs are mutually exclusive. Finally, it appears Encounternet can be useful for data collection when paired with live observations, as long as certain limitations are kept in mind. Our pilot study could be beneficial to anyone considering the use of remote detection tools in data collection on animals.