Strong Philopatry, Isolation by Distance, and Local Habitat Have Promoted Genetic Structure in Heermann’s Gull
Misael Daniel Mancilla-Morales,
Enriqueta Velarde,
Andres Aguilar,
Araceli Contreras-Rodríguez,
Exequiel Ezcurra,
Jesús A. Rosas-Rodríguez,
José G. Soñanez-Organis,
Enrico A. Ruiz
Affiliations
Misael Daniel Mancilla-Morales
Departamento de Zoología, Escuela Nacional de Ciencias Biológicas, Instituto Politécnico Nacional, Colonia Santo Tomás, Ciudad de México 11340, Mexico
Enriqueta Velarde
Instituto de Ciencias Marinas y Pesquerías, Universidad Veracruzana, Hidalgo 617, Colonia Río Jamapa, Boca del Río 94290, Mexico
Andres Aguilar
Department of Biological Sciences, California State University, Los Angeles, CA 90032, USA
Araceli Contreras-Rodríguez
Departamento de Microbiología, Escuela Nacional de Ciencias Biológicas, Instituto Politécnico Nacional, Colonia Santo Tomás, Ciudad de México 11340, Mexico
Exequiel Ezcurra
Department of Botany and Plant Sciences, University of California, Riverside, CA 92521, USA
Jesús A. Rosas-Rodríguez
Departamento de Ciencias Químico-Biológicas y Agropecuarias, Universidad de Sonora, Colonia Francisco Villa, Navojoa 85880, Mexico
José G. Soñanez-Organis
Departamento de Ciencias Químico-Biológicas y Agropecuarias, Universidad de Sonora, Colonia Francisco Villa, Navojoa 85880, Mexico
Enrico A. Ruiz
Departamento de Zoología, Escuela Nacional de Ciencias Biológicas, Instituto Politécnico Nacional, Colonia Santo Tomás, Ciudad de México 11340, Mexico
Philopatry can promote genetic differentiation among populations but remains undescribed in many seabirds. Hence, we explored such associations in Heermann’s Gull. Philopatry was observed monitoring 998 gulls in Rasa Island, while genetic differences were examined in the Cardonosa, Rasa, and Isabel islands using the cytochrome b of 296 gulls. Adults returned repeatedly to its natal valley or to a very close distance from it under different modelled hypotheses. Likewise, the interaction between sex and distance indicated significant male-biased philopatry. Besides, low to high genetic differentiation was observed between the Rasa and Cardonosa islands (ΦST = 0–0.22) (both in the Midriff Islands Region), but higher genetic differentiation against Isabel Island (ΦST > 0.25) (in the Mexican Province region). Consistently, genetic structure among regions was observed using different approaches (AMOVA: ΦCT = 0.49; SAMOVA: FCT = 0.49; and BAPS: K = 2). Similarly, a pattern of isolation by distance (rM = 0.82, p = 0.03), agrees with lower estimates of scaled migration rates between regions than among islands of the same region. Overall, it is suggested that the genetic structure found in Heermann’s Gull has been promoted by physical and behavioral barriers.
