Baleen whale species are highly migratory, travelling between high-latitude feeding grounds in summer and tropical breeding and calving grounds in winter. Previous research has established relationships between baleen whales and a variety of local environmental conditions they encounter as part of their life history, however information on diel activity patterns remains scarce.
Here, we report on the current state of knowledge on this subject. A comprehensive assessment of the peer-reviewed literature was carried out, synthesizing what is known in the context of behavioural mode (i.e. breeding, feeding, or migration) and species of interest. Results show that most data relate to breeding and feeding ground behaviours (e.g. singing in humpback whales, or blue whale feeding dives in response to vertical migration of prey) while diel activity patterns during migration are mostly unknown. Furthermore, there was a difference in studied species, with humpback whales receiving the most attention.
An increased understanding of diel behaviours in baleen whales may improve our understanding of their distribution. We illustrate this through outputs of both a Species Distribution Model, and an agent-based model of humpback whales in Australia. In turn, this may aid conservation efforts in areas where human activities (e.g. shipping lanes) and whales meet.