Using a multi-disciplinary approach to identify a critically endangered killer whale management unit.

• Published in: Ecological Indicators
• Main Authors: Estebana, Ruth, Verborgh, Philippe, Gauffier, Pauline, Giménez, Joan, Martín, Vidal, Pérez-Gil, Mónica, Tejedor, Marisa, Almunia, Javier, Jepson, Paul D., García-Tíscar, Susana, Barrett-Lennard, Lance G., Guinet, Christophe, Foote, Andrew D., de Stephanis, Renaud
• Other Authors: CIRCE (Conservation, Information and Research on Cetaceans), Estación Biológica de Doñana (EBD), Consejo Superior de Investigaciones Cientificas España = Spanish National Research Council Spain (CSIC), Sociedad de Estudios de Cetáceos en Canarias (SECAC), Université Paris Diderot - Paris 7 (UPD7), Loro Parque Fundacion, Institute of Zoology, Zoological Society of London, Department of Ecology, Universidad Autónoma de Madrid (UAM), Department of Zoology, University of British Columbia (UBC), Coastal Oceans Research Institute, Centre d'Études Biologiques de Chizé - UMR 7372 (CEBC), Institut National de la Recherche Agronomique (INRA)-La Rochelle Université (ULR)-Centre National de la Recherche Scientifique (CNRS), Computational and Molecular Population Genetics (CMPG), Institute of Ecology and Evolution, Universität Bern / University of Bern (UNIBE)
• Format: Article in Journal/Newspaper
• Language: English
• Published: HAL CCSD 2016
• Subjects: Social structure; Genetics; Stable isotopes; Pollutants; Conservation; [SDE]Environmental Sciences; Sog; Killer Whale; Killer whale
• Online Access: https://hal.science/hal-01327893; https://doi.org/10.1016/j.ecolind.2016.01.043

International audience A key goal for wildlife managers is identifying discrete, demographically independent conservation units.Previous genetic work assigned killer whales that occur seasonally in the Strait of Gibraltar (SoG) andkiller whales sampled off the Canary Islands (CI) to the same population. Here we present new analysesof photo-identification and individual genotypes to assess the level of contemporary gene flow andmigration between study areas, and analyses of biomarkers to assess ecological differences. We identified47 different individuals from 5 pods in the SoG and 16 individuals in the CI, with no matches foundbetween the areas. Mitochondrial DNA control region haplotype was shared by all individuals sampledwithin each pod, suggesting that pods have a matrifocal social structure typical of this species, whilstthe lack of shared mitogenome haplotypes between the CI and SoG individuals suggests that there waslittle or no female migration between groups. Kinship analysis detected no close kin between CI and SoGindividuals, and low to zero contemporary gene flow. Isotopic values and organochlorine pollutant loadsalso suggest ecological differences between study areas. We further found that one individual from a podwithin the SoG not seen in association with the other four pods and identified as belonging to a potentialmigrant lineage by genetic analyses, had intermediate isotopic values and contaminant between thetwo study areas. Overall our results suggest a complex pattern of social and genetic structuring correlatedwith ecological variation. Consequently at least CI and SoG should be considered as two differentmanagement units. Understanding this complexity appears to be an important consideration when monitoringand understanding the viability of these management units. Understand the viability will helpthe conservation of these threatened management units.