Initial description of short-finned pilot whale (Globicephala macrorhynchus) genetic diversity from the Caribbean

• This study presents the first genetic information about short-finned pilot whale populations in the Caribbean.
• One unique mitochondrial Control Region haplotype was detected in Caribbean pilot whales.
• Relatedness analyses revealed a high likelihood of related animals in one strading in the British Virgin Islands.

Short-finned pilot whales (Globicephala macrorhynchus) are known for their highly social cohesive behavior which contributes to the reporting by the public of mass stranding. This species has been hunted in the Lesser Antilles in the Caribbean for generations. Currently, the genetic diversity of short-finned pilot whales has been investigated in the North Atlantic, South Pacific and Japan/Korea, but not in the Caribbean. Here we provide the first description of the genetic diversity of this species in the Caribbean using mitochondrial DNA (mtDNA) control region (CR) sequences and seven microsatellite loci from 25 skin samples collected from four stranding events in Jamaica, Puerto Rico, British Virgin Islands, and Trinidad and Tobago. Overall, three CR haplotypes were identified; of these, one was unique for the Caribbean (Car 1), while a second (haplotype D) was previously reported in the Western North Atlantic, and a third (Haplotype A) was found to be common in the South Pacific. Even though sample size (n = 25) was small, microsatellite analysis showed a low level of relatedness between the stranded whales. Our results provide relevant preliminary information on the genetic diversity of short-finned pilot whales in the Caribbean, reporting one previously unknown and unique haplotype for this region. Further research should be carried out in the Caribbean to further our knowledge on this species, particularly since its prone to mass stranding.