Southern right whales in the Central and Southeast Pacific (Chile-Peru population): sightings, body condition and mtDNA haplotypes of mother-calf pairs

The critically endangered subpopulation of southern right whales (SRWs; Eubalaena australis) in the southeast Pacific Ocean (Chile-Peru) is poorly studied due to its low abundance. In the last five years the number of sightings of mother-calf pairs along the Chilean coast increased, however, it is not clear if this increase represents population growth. Here, we examine the body condition of two SRWs sighted in northern Chile, one in Tocopilla (~22ºS) in 2023 and the other in Antofagasta (~23ºS) in 2019.We also examined mitochondrial DNA (mtDNA) haplotype diversity of the mother sighted off Tocopilla and another mother observed in northern Peru in 2022. Additionally, we provide a new sighting of a SRW mother-calf pair off Pitcairn Islands (~25ºS) in 2023. Results show that the Chilean mothers are in similar body condition to those from the healthy and recovering populations from Argentina and Australia. MtDNA haplotypes from Chilean and Peruvian mothers were the same
as the haplotypes documented in Argentinian SRWs. All opportunistic data obtained from SRWs in the Central and Southeast Pacific are important to help better understand the status of the critically endangered Chile-Peru population.