Avistamientos de Orcinus orca (Linnaeus, 1758) (Cetartiodactyla: Odontoceti: Delphinidae) en el Pacífico costarricense (1990-2020)

2021 ◽

pp. 29-47

Author(s):

César Castro-Azofeifa

Keyword(s):

Las orcas son cetáceos poco estudiados en el trópico, y sus desplazamientos por aguas costarricenses han sido escasamente abordados. Son animales de gran importancia ecológica debido a su rol como depredadores top, y documentar su presencia en el país puede ser de gran importancia científica y social, pues para las comunidades costeras esta información podría representar una gran oportunidad desde el punto de vista ecoturístico. El objetivo de esta investigación fue sintetizar y sistematizar los reportes existentes, referente a las orcas en el país, mediante publicaciones científicas, libros e información derivada de informes de ciudadanos. Se tomó en cuenta la información recabada hasta el 31 de diciembre de 2020. Se dividieron los avistamientos y el número de orcas en el Pacífico costarricense regionalmente: 17 avistamientos y 56 individuos para el Pacífico Sur, 7 avistamientos y 20 individuos para el Pacífico Norte, 3 avistamientos y 19 individuos en el Pacífico Central y 4 avistamientos y 10 individuos para la Isla del Coco. Se contabilizaron 31 avistamientos y 105 individuos en total. No se encontraron diferencias estadísticamente significativas sobre la ocurrencia de orcas entre las zonas, aunque hay una mayor cantidad de reportes en el Pacífico Sur, en especial, durante setiembre. Estudiar la presencia de las orcas en el país, que involucren procesos de educación ambiental y ciencia ciudadana, puede proveer importantes herramientas para la formulación de políticas públicas que permitan una conservación efectiva de los cetáceos y ofrecer mayores oportunidades de crecimiento para la industria ecoturística en las costas.

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Personality in captive killer whales (Orcinus orca): A rating approach based on the five-factor model.

Journal of Comparative Psychology ◽

10.1037/com0000146 ◽

2019 ◽

Vol 133 (2) ◽

pp. 252-261 ◽

Cited By ~ 1

Author(s):

Yulán Úbeda ◽

Sara Ortín ◽

Judy St. Leger ◽

Miquel Llorente ◽

Javier Almunia

Keyword(s):

Factor Model ◽

Five Factor Model ◽

Orcinus Orca ◽

Killer Whales

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Surface-Based Observations Can Be Used to Assess Behavior and Fine-Scale Habitat Use by an Endangered Killer Whale (Orcinus orca) Population

Aquatic Mammals ◽

10.1578/am.42.2.2016.168 ◽

2016 ◽

Vol 42 (2) ◽

pp. 168-183 ◽

Cited By ~ 3

Author(s):

Dawn P. Noren ◽

Donna D. W. Hauser

Keyword(s):

Habitat Use ◽

Killer Whale ◽

Orcinus Orca ◽

Fine Scale

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Depredation by Killer Whales (Orcinus orca) on a Blue Shark (Prionace glauca) in Northeastern Atlantic

Aquatic Mammals ◽

10.1578/am.46.5.2020.478 ◽

2020 ◽

Vol 46 (5) ◽

pp. 478-482

Author(s):

Gonzalo Mucientes ◽

Adriana González-Pestana

Keyword(s):

Orcinus Orca ◽

Killer Whales ◽

Blue Shark ◽

Prionace Glauca ◽

Northeastern Atlantic

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Orcinus orca: Reeves, R., Pitman, R.L. & Ford, J.K.B.

IUCN Red List of Threatened Species ◽

10.2305/iucn.uk.2017-3.rlts.t15421a50368125.en ◽

2017 ◽

Cited By ~ 3

Author(s):

Keyword(s):

Orcinus Orca

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Family feud: permanent group splitting in a highly philopatric mammal, the killer whale (Orcinus orca)

Behavioral Ecology and Sociobiology ◽

10.1007/s00265-021-02992-8 ◽

2021 ◽

Vol 75 (3) ◽

Author(s):

Eva H. Stredulinsky ◽

Chris T. Darimont ◽

Lance Barrett-Lennard ◽

Graeme M. Ellis ◽

John K. B. Ford

Keyword(s):

Killer Whale ◽

Group Structure ◽

Group Living ◽

Orcinus Orca ◽

Learning Approaches ◽

Killer Whales ◽

Internal Factors ◽

Individual Fitness ◽

Leadership Experience

Abstract For animals that tend to remain with their natal group rather than individually disperse, group sizes may become too large to benefit individual fitness. In such cases, group splitting (or fission) allows philopatric animals to form more optimal group sizes without sacrificing all familiar social relationships. Although permanent group splitting is observed in many mammals, it occurs relatively infrequently. Here, we use combined generalized modeling and machine learning approaches to provide a comprehensive examination of group splitting in a population of killer whales (Orcinus orca) that occurred over three decades. Fission occurred both along and across maternal lines, where animals dispersed in parallel with their closest maternal kin. Group splitting was more common: (1) in larger natal groups, (2) when the common maternal ancestor was no longer alive, and (3) among groups with greater substructuring. The death of a matriarch did not appear to immediately trigger splitting. Our data suggest intragroup competition for food, leadership experience and kinship are important factors that influence group splitting in this population. Our approach provides a foundation for future studies to examine the dynamics and consequences of matrilineal fission in killer whales and other taxa. Significance statement Group living among mammals often involves long-term social affiliation, strengthened by kinship and cooperative behaviours. As such, changes in group membership may have significant consequences for individuals’ fitness and a population’s genetic structure. Permanent group splitting is a complex and relatively rare phenomenon that has yet to be examined in detail in killer whales. In the context of a growing population, in which offspring of both sexes remain with their mothers for life, we provide the first in-depth examination of group splitting in killer whales, where splitting occurs both along and across maternal lines. We also undertake the first comprehensive assessment of how killer whale intragroup cohesion is influenced by both external and internal factors, including group structure, population and group demography, and resource abundance.

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