Allometric growth of swimming-associated elements in Short-finnedpilot whales Globicephala macrorhynchus Gray 1846 (Cetacea: Delphinidae)

Ongoing research on cetaceans is revealing species-specific traits that reflect adaptations to different environmental conditions. Short-finned pilot whales are no exception to this trend. This species exhibits a specific diving behaviour, characterized by short bursts of acceleration at great depths, which likely necessitates special hydrodynamic adaptations in their body structure. Examining the growth rate of the structures involved in swimming could offer valuable insights. However, research to date has focused only on the allometric growth of these structures in this species from newborns to adults. No studies have yet explored the different growth phases of the species, which are related to its ecological context. This study examined the growth rates of four structural elements associated with swimming in individuals of both sexes, analysed separately across the four main growth phases. This research focused on a group that was stranded in Yucatan, Mexico, in 1986. This group included individuals ranging from newborns to asymptotic adults of both sexes. The findings in this work indicate that there is variation in the growth rate during certain phases. On the other hand, despite this species exhibiting strong social cohesion and often stranding in large groups that include individuals from all age classes, there is a lack of research on its growth. Therefore, a cumulative study of the allometric growth of the swimming structures of this species is proposed. This study will incorporate consecutive stranding data to create a comprehensive body of knowledge. By systematically and cumulatively studying the changes in different strandings of short-finned pilot whales worldwide, researchers around the world, in a joint effort, will identify key factors that will help understand the species’ optimal diving behaviour at great depths. With regard to the species’ conservation status, global and local information is insufficient at present. It is important that, alongside ecological studies, research is carried out on the species’ physiology and biomechanics, which will contribute to effective management and conservation policies.