New subspecies of bottlenose dolphins discovered by marine biologist

By NASA –, Public Domain,

A bottlenose dolphin subspecies previously unknown outside of the eastern tropical Pacific Ocean has been discovered by a marine scientist at the University of Miami’s Rosenstiel School of Marine, Atmospheric, and Earth Science. Ana Costa, Ph.D., a Rosenstiel lecturer specializing in marine mammalogy, said, while there is a common perception that all dolphin species are already recognized, developments in technology and approaches are helping to discover a larger richness in more recent years.

The Eastern Tropical Pacific bottlenose dolphin (Tursiops truncatus nuuanu) is a new subspecies of the common bottlenose dolphin discovered by Costa and colleagues from the National Oceanic and Atmospheric Administration. She also mentioned that the dolphins are most likely to be found in the far offshore areas between southern Baja California and the Galapagos Islands.

This study, initiated in 2016, by Costa and colleagues measured and analyzed the skull morphology and total length of common bottlenose dolphin specimens preserved in numerous American museums. These specimens were originally acquired in the Pacific Ocean. Analysis of bottlenose dolphin species was performed using multivariate and clustering methods.

Common bottlenose dolphins are found mostly in the eastern and western North Pacific waters, and the researchers discovered two unique morphological clusters: the new subspecies located in the eastern tropical Pacific (ETP), and the common bottlenose dolphins found across the rest of the Pacific. The unique oxygen and salinity levels and temperature conditions in these seas may be causing the ETP bottlenose dolphins to diversify.

The study’s author, Costa, reflected on its significance, noting that a better knowledge of marine mammal populations is crucial for maintaining and protecting various species and subspecies during this era of global warming. She also emphasized the importance of making marine life protection and management a global priority.


A. P. B. Costa et al. (2022). Tursiops truncatus nuuanu, a new subspecies of the common bottlenose dolphin from the eastern tropical Pacific, Journal of Mammalian EvolutionDOI: 10.1007/s10914-022-09641-5