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Laysan Albatross on Guadalupe Island, MÃ Monographs of the Western North American Naturalist Volume 7 8th California Islands Symposium Article 38 12-31-2014 Laysan Albatross on Guadalupe Island, México: current status and conservation actions Julio C. Hernández-Montoya Grupo de Ecología y Conservación de Islas, A.C., [email protected] Luciana Luna-Mendoza Centre for Biodiversity and Biosecurity, University of Auckland, [email protected] Alfonso Aguirre-Muñoz Grupo de Ecología y Conservación de Islas, A.C., [email protected] Federico Méndez-Sánchez Grupo de Ecología y Conservación de Islas, A.C., [email protected] Maria Maria Félix-Lizárraga Grupo de Ecología y Conservación de Islas, A.C., Baja California, Mexico, [email protected] See next page for additional authors Follow this and additional works at: https://scholarsarchive.byu.edu/mwnan Recommended Citation Hernández-Montoya, Julio C.; Luna-Mendoza, Luciana; Aguirre-Muñoz, Alfonso; Méndez-Sánchez, Federico; Maria Félix-Lizárraga, Maria; and Barredo-Barberena, J. M. (2014) "Laysan Albatross on Guadalupe Island, México: current status and conservation actions," Monographs of the Western North American Naturalist: Vol. 7 , Article 38. Available at: https://scholarsarchive.byu.edu/mwnan/vol7/iss1/38 This Monograph is brought to you for free and open access by the Western North American Naturalist Publications at BYU ScholarsArchive. It has been accepted for inclusion in Monographs of the Western North American Naturalist by an authorized editor of BYU ScholarsArchive. For more information, please contact [email protected], [email protected]. Laysan Albatross on Guadalupe Island, México: current status and conservation actions Authors Julio C. Hernández-Montoya, Luciana Luna-Mendoza, Alfonso Aguirre-Muñoz, Federico Méndez-Sánchez, Maria Maria Félix-Lizárraga, and J. M. Barredo-Barberena This monograph is available in Monographs of the Western North American Naturalist: https://scholarsarchive.byu.edu/mwnan/vol7/iss1/38 Monographs of the Western North American Naturalist 7, © 2014, pp. 543–554 LAYSAN ALBATROSS ON GUADALUPE ISLAND, MÉXICO: CURRENT STATUS AND CONSERVATION ACTIONS Julio C. Hernández-Montoya1,3, Luciana Luna-Mendoza1,2, Alfonso Aguirre-Muñoz1, Federico Méndez-Sánchez1, Maria Félix-Lizárraga1, and J.M. Barredo-Barberena1 ABSTRACT.—Guadalupe Island, off the Baja California peninsula, México, hosts the most important growing Laysan Albatross (Phoebastria immutabilis) breeding colony in the eastern Pacific. Since this seabird’s first arrival in 1983, it has been affected by predation from feral cats (Felis catus), present on Guadalupe since the late 19th century. Heavy preda- tion events have been recorded on the island, so we initiated a feral cat control campaign in 2003 and began collecting baseline information for developing an eradication plan. At the same time, we conducted seasonal monitoring of Laysan Albatross reProductive success in order to assess the benefits from control activities. Cat relative abundance on Guadalupe was estimated through spotlight surveys, and control was done at the southernmost end of the island around the 2 locations where Laysan Albatross nest: Colinas Negras and Punta Sur. Laysan Albatross population growth rate was calculated based on the number of reproductive individuals, while breeding success was estimated as the propor- tion of laid eggs that resulted in fledged chicks. A total of 203 cats were removed from the south end of Guadalupe between 2003 and 2013. During this same period, high reproductive success (0.8) was recorded for Laysan Albatross, suggesting a positive effect of cat control activities. We found significant differences in reproductive success between years with predation and no predation by feral cats. The Laysan Albatross colony on Guadalupe has grown steadily dur- ing the past 30 years, increasing from 4 to 143 breeding pairs between 1984 and 2013, respectively, and with a popula- tion growth rate of 1.10 between 2004 and 2013. RESUMEN.—La Isla Guadalupe, frente a la península de Baja California, México, alberga la colonia reproductora más importante y en crecimiento de albatros de Laysan (Phoebastria immutabilis) en el Pacífico Oriental. Desde su llegada en 1983, esta ave marina ha sido afectada Por la dePredación Por Parte de gatos ferales (Felis catus), Presentes en Guadalupe desde el siglo XIX. Se han registrado fuertes eventos de depredación en la isla, por lo que en 2003 iniciamos una campaña de control, acompañada del registro de información de línea base para el desarrollo de un plan de erradi- cación. Al mismo tiempo, se inició el monitoreo estacional del éxito reproductivo del albatros de Laysan a fin de evaluar los beneficios derivados del control. La abundancia relativa de gato se estimó mediante conteos nocturnos usando faros incandescentes o “spotlights,” mientras que el control se hizo con trampas de cepo en el sur de la isla, en las dos zonas donde anida el albatros de Laysan: Colinas Negras y Punta Sur. La tasa de crecimiento Poblacional del albatros de Laysan se calculó con base en el número de individuos reproductivos, en tanto que el éxito reproductivo se estimó de acuerdo a la proporción de huevos puestos que resultaron en volantones. Entre 2003 y 2013 se eliminaron un total de 203 gatos en la porción sur de Guadalupe. Durante este mismo periodo se registró, en general, un éxito reproductivo alto (0.8) en el albatros de Laysan, lo que sugiere que el control de gato tiene un efecto positivo. Encontramos diferen- cias significativas en el éxito reproductivo entre los años con y sin depredación por gatos ferales. La colonia de albatros de Laysan en Guadalupe ha crecido de manera estable durante los últimos 30 años, pasando de 4 a 143 pares reproduc- tores entre 1984 y 2013, respectivamente, teniendo una tasa de crecimiento poblacional de 1.10 entre 2004 y 2013. The feral cat (Felis catus) is among the ble to cat Predation: they are long-lived sPe - world’s worst invasive alien sPecies (Lowe et cies with low reProductive rates (usually a al. 2004). Its Presence on islands has been single chick Per breeding cycle) and have recognized as one of the main causes of late recruitment, as they start to reProduce extinction of insular sPecies (e.g., Jehl and around 7–12 years of age (Cairns 1992, Ba - Parkes 1983, Mellink 1992, Veitch 2001). ker et al. 2002). Furthermore, seabirds— Cats on islands have contributed to the ex - like many insular sPecies—lack antiPredator tinction of 33 mammals, birds, and rePtiles behavior since they have evolved in environ- worldwide (Aguirre-Muñoz et al. 2011, Med- ments free of mammalian Predators (Milberg ina et al. 2011). Seabirds have several charac- and Tyrberg 1993, Cooper and Pérez-Mellado teristics that make them Particularly vulnera- 2012). 1Grupo de Ecología y Conservación de Islas, A.C., Moctezuma 836, Zona Centro, Ensenada, Baja California, México 22800. 2Centre for Biodiversity and Biosecurity, University of Auckland, Private Bag 92019, Auckland, New Zealand 1142. 3E-mail: [email protected] 543 544 MONOGRAPHS OF THE WESTERN NORTH AMERICAN NATURALIST [Volume 7 GuadaluPe Island remains one of the both adults and chicks (Gallo-Reynoso and most imPortant breeding sites for seabirds in Figueroa-Carranza 1996, Keitt et al. 2005, this Mexico (e.g., Pitman et al. 2004, Keitt 2005, PaPer). Laysan Albatrosses are reluctant to Wolf et al. 2005, Birt et al. 2012). It hosts 7 leave their nests when they are incubating threatened seabirds: GuadaluPe Storm-Petrel (KePler 1967), and this characteristic makes (Oceanodroma macrodactyla), Laysan Alba- them highly vulnerable to Predation. For ex - tross (Phoe bastria immutabilis), Leach’s Storm- ample, in the 2002–2003 breeding season, 35 Petrel (Oceanodroma leucorhoa socorroensis breeding adults were killed by cats on Gua - and O. l. cheimomnestes), Guadalupe Murrelet dalupe, causing the failure of their nests (Keitt (Synthliboramphus hypoleucus), Cassin’s Auk- et al. 2005). let (Ptychoramphus aleuticus), and Black-vented To actively Protect all seabird PoPulations Shearwater (Puffinus opistho melas). Cats were on GuadaluPe Island, including the Laysan introduced to Guadalupe around 1885, rapidly Albatross, the eradication of feral cats has establishing a feral PoPulation (Moran 1996). been identified as a key restoration strategy Over the years, feral cats became a major con- (Aguirre-Muñoz et al. 2011, Croxall et al. 2012, cern for the conservation of birds at Guada - Aleixandre et al. 2013, Nogales et al. 2013). luPe Island (Jehl and Everett 1985). They Nevertheless, even when eradication is the have been involved in the extinction of 6 bird preferred option, sometimes control has to be taxa, including the GuadaluPe Storm-Petrel the immediate resPonse to a sPecies conser - (not recorded since 1912), the GuadaluPe Ruby- vation contingency (CourchamP et al. 2003), crowned Kinglet (Regulus calendula obscu- especially while fundraising for usually expen- rus), and the GuadaluPe Northern Flicker sive eradication campaigns. There are several (Colaptes auratus rufipileus; Jehl and Everett examPles of how ongoing feral cat control 1985, Barton et al. 2004, Keitt et al. 2005, strategies have protected seabird populations, Aguirre-Muñoz et al. 2011). Particularly when eradication of feral cats is Almost the entire Laysan Albatross PoPu- not feasible due to technological or financial lation breeds in the central Pacific (north- constraints (e.g., Bonnaud et al. 2010, Zino western Hawaiian Islands); but in 1983, the et al. 2001). At Port-Cros Island (France), for species colonized Guadalupe—the first colony examPle, feral cat control around Yelkouan in the eastern Pacific—probably due to satura- Shearwater (Puffinus yelkouan) colonies led to tion of breeding sites in its former location an increase in and immediate protection of the (Pitman et al. 2004). Since then, new colonies population (Bonnaud et al. 2010). have been recorded in the eastern Pacific, all To ensure the Permanence of the Laysan within Mexico (Islas Alijos, Roca Partida, San Albatross on GuadaluPe, a camPaign to con - Benedicto, and Clarion Islands in the Revi - trol feral cats was started in 2003.
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