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Double-crested Cormorant (Phalacrocorax auritus albociliatus) nest distribution, abundance, and chronology on Isla Alcatraz

Project Description

Isla Alcatraz supports the largest Double-crested Cormorant nesting colony in the Gulf of California. In 1997, a pilot project focusing on monitoring the colony was initiated by Prescott College. Since 2001 seasonal monitoring has been continued to observe population changes and trends over time.

In the 2013-2014 season we initiated a productivity study of the Double-crested Cormorant population in order to collect data on nesting success. We are continuing this project this year and into the future with the hope that by collecting more detailed information, we can better understand population dynamics on Isla Alcatraz.

Project Results

Nest counts of Double-crested Cormorants on Isla Alcatraz have ranged from 605 in 2013 to 1968 in 2011 with an average of 1363 nests. This accounts for an estimated 5.7% of the Pacific coast population and 35.7% of the Gulf of California population. In 2013-2014 the breeding population failed with a peak of 605 active nests, a mid-season low of 88 nests, and fewer than 5 fledgling chicks observed. These results demonstrate how long-term monitoring by Prescott College is vital to the conservation and management of this critical cormorant population.

Reports & Publications

  1. Reporte de proyectos de investigación en el Área de Protección deFlora y Fauna Islas del Golfo de California 2010-11 Centro de Estudios Culturales y Ecológicos Prescott College A. C., Bahía Kino, Sonora
  2. Research and Conservation Program Report (2007-2011), Prescott College Kino Bay Center for Cultural and Ecological Studies
  3. Fleishman, A. B. (2010, 2-5 March 2010). Monitoreo del cormorán doble-cresta (Phalacrocorax auritus albociliatus) en Isla Alcatraz, Bahía de Kino, Sonora, México 2009-2010. Paper presented at the XII Congreso de la Asociación del Mar de Cortés y VI Simposium Internacional sobre el Mar de Cortés, Guaymas, Sonora
  4. Reporte de proyectos de investigación en el Area de Proteccion de Flora y Fauna Islas del Golfo de California 2009-2010, Centro de Estudios Culturales y Ecológicos Prescott College A. C., Bahía Kino, Sonora
  5. Duberstein, J. N., Jimenez-Serrania, V., Pfister, T., Lindquist, K., & Meltzer, L. (2005). Breeding Double-Crested Cormorants and Wading Birds on Isla Alcatraz, Sonora, México. Paper presented at the Third International Partners in Flight Conference, March 20-24, 2002, , Asilomar Conference Grounds, California 
  6. Pfister, T., Pfister, B., Jiménez-Serranía, V., de-Pedro-Díaz, D., Suárez-Gracida, G., & Duberstein, J. N. (2005). Assessment of the nesting population of Double-crested Cormorants (Phalacrocorax auritus albociliatus) on Isla Alcatraz, Gulf of California, Mexico. Marine Ornithology 33, 195–197. 
  7. Prescott College, A. C. (2005). Programa de Conservación y Manejo Área de Protecion de Flora y Fauna de Isla Alcatraz. Prescott College. Bahia Kino, Sonora, Mexico.
  8. Duberstein, J., Jimenez-Serrania, V., Lindquist, K., & Meltzer, L. (2001). Breeding Double-crested Cormorants and Wading Birds on Isla Alcatraz, Sonora, Mexico. Paper presented at the Partners in Flight Conference, Asilomar, CA.