Increasing nest success in the yellow-shouldered blackbird Agelaius xanthomus in southwest Puerto Rico

López-Ortiz, Ricardo; Ventosa-Febles, Eduardo A.; Reitsma, Leonard R.; Hengstenberg, D.; DeLuca, William V.

doi:10.1016/s0006-3207(02)00122-2

Cited by 14 publications

(7 citation statements)

References 6 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In addition, during the last century they have invaded the Caribbean (Cruz et al 1989) and at present they are invading North America (Post et al 1993, Kluza 1998, Post and Sykes 2011). There are several reports of this species parasitizing threatened passerines like the ‘Critically Endangered’ Pale-headed Brush-finch Atlapetes pallidiceps (Oppel et al 2004), the ‘Endangered’ Yellow-shouldered Blackbird Agelaius xanthomus (Wiley et al 1991, López Ortiz et al 2002) and the ‘Vulnerable’ Saffron-cowled Blackbird Xanthopsar flavus (Fraga et al 1998). The main impact of Shiny Cowbirds when they parasitize hosts that are similar or larger in body mass is the puncture of host eggs, which increases the probability of nest abandonment (Reboreda et al 2003).…”

Section: Discussionmentioning

confidence: 99%

Impact of Shiny Cowbird and botfly parasitism on the reproductive success of the globally endangered Yellow CardinalGubernatrix cristata

Domínguez

Reboreda

Mahler

2014

Bird Conservation International

View full text Add to dashboard Cite

SummaryThe Yellow Cardinal Gubernatrix cristata is a globally endangered passerine endemic to southern South America. Although the conservation status of this species is alarming, there is no information about factors that affect its reproductive success. We studied the breeding biology of a Yellow Cardinal population in Corrientes province in north-east Argentina and report reproductive parameters, such as timing of breeding, clutch size, hatching success and chick survival and analyse factors influencing nest survival. The breeding season lasted from October to December with most nesting attempts occurring during the second half of November. Re-nesting after nest failure occurred in approximately 35% of pairs but we did not observe re-nesting after successful attempts. Modal clutch size was three eggs and successful nests fledged on average 1.6 chicks. We observed brood parasitism by Shiny Cowbirds Molothrus bonariensis in 33% of the nests. The main cost of brood parasitism was the puncture of cardinal eggs by cowbird females, which very often resulted in nest abandonment. Another factor reducing reproductive success was parasitism by botflies Philornis sp., which occurred in 22% of the nests and reduced chick survival. We determined daily nest survival rate with MARK software and found that during the egg stage, it decreased with time of breeding and brood parasitism by Shiny Cowbirds. Our results indicate that Shiny Cowbird and botfly parasitism represent a threat for Yellow Cardinals. Conservation actions to protect the remaining populations of Yellow Cardinals should consider the impact of Shiny Cowbird parasitism.

show abstract

Section: Discussionmentioning

confidence: 99%

Impact of Shiny Cowbird and botfly parasitism on the reproductive success of the globally endangered Yellow CardinalGubernatrix cristata

Domínguez

Reboreda

Mahler

2014

Bird Conservation International

View full text Add to dashboard Cite

show abstract

“…Other components of blackbird management include ANS, removal of cowbird eggs, control of ectoparasites, reduction of nest piracy and predation, prevention of habitat loss, and patrolling the area to prevent human disturbance (Wiley et al 1991, USFWS 1996, Lopez-Ortiz et al 2002. Other components of blackbird management include ANS, removal of cowbird eggs, control of ectoparasites, reduction of nest piracy and predation, prevention of habitat loss, and patrolling the area to prevent human disturbance (Wiley et al 1991, USFWS 1996, Lopez-Ortiz et al 2002.…”

Section: Conclusion and Recommendationsmentioning

confidence: 99%

Ecology and Management of Shiny Cowbirds (Molothrus bonariensis) and Endangered Yellow-Shouldered Blackbirds (Agelaius xanthomus) in Puerto Rico

Cruz¹,

López-Ortiz²,

Ventosa-Febles³

et al. 2005

Ornithological Monographs

Self Cite

View full text Add to dashboard Cite

JSTOR is a not-for-profit service that helps scholars, researchers, and students discover, use, and build upon a wide range of content in a trusted digital archive. We use information technology and tools to increase productivity and facilitate new forms of scholarship. For more information about JSTOR, please contact support@jstor.org.. University of California Press and AmericanOrnithologists' Union are collaborating with JSTOR to digitize, preserve and extend access to Ornithological Monographs.Abstract.-Historically, the Shiny Cowbird (Molothrus bonariensis; hereafter "cowbird") was confined to South America, Trinidad, and Tobago. Within the past century, cowbirds have expanded their range into the West Indies, bringing them into contact with avian communities that have never experienced brood parasitism. Because of their small populations, high degree of isolation, and lack of experience with cowbirds, West Indian birds are at greater risk of harm from cowbird contact than mainland birds. Cowbird parasitism was the single most important factor in the reduced reproductive output of the endangered Yellow-shouldered Blackbird (Agelaius xanthomus; hereafter "blackbird"), a Puerto Rican endemic. Roost counts estimated that the blackbird population declined in southwestern Puerto Rico from 1,663 individuals (1974)(1975) to 266 (1981-1982). Cowbird trapping in upland areas near blackbird nesting areas in mangroves and cowbird feeding areas has proved successful in managing cowbirds and increasing blackbird populations. Removal of cowbird eggs and nestlings from artificial nesting structures has resulted in fewer parasitized blackbird nests. As a result of those measures, cowbird parasitism of blackbirds has fallen from 95% (1973-1983) to <3% (2000-2003) and, judging from roost counts in 2004, the blackbird population has increased to 800 individuals in southwestern Puerto Rico. Cowbird management programs have excellent potential to reduce the adverse effects of cowbird parasitism; however, trapping within nesting areas is not recommended, because it may increase *he probability of capturing and stressing breeding blackbirds. Resumen.-Historicamente, Molothrus bonariensis estaba confinado a Sudamerica, Trinidad, y Tobago. A lo largo del siglo pasado, Molothrus bonariensis ha expandido su area a las IndiasOrientales, lo que los ha puesto en contacto con comunidades de aves que nunca antes habian experimentado el parasitismo de cria. Debido a su pequeno tamano poblacional, alto grado de aislamiento, y falta de experiencia previa con Molothrus, las aves de las Indias Orientales estan en un mayor riesgo de dano causado por los tordos que las especies continentales. El parasitismo por el Molothrus bonariensis fue el unico y mas importante factor responsable de la reduccion del exito reproductivo de Agelaius xanthomus, una especie en peligro endemica de Puerto Rico. Mediante conteos en dormideros se estimo que la poblacion Agelaius xanthomus disminuyo en el sudeste de Puerto Rico de 1,663 individuos (1974-1975) a 266 (19...

show abstract

“…Experimental studies of individual plasticity in mating tactics in response to variation in conspecifi c density or sex ratio might be feasible and relevant in many understudied populations of cowbirds where those parasites are managed (i.e. removed) for conservation purposes (Griffi ths and Griffi ths 2000, Lopez-Ortiz et al 2002).…”

Section: More Puzzling Questionsmentioning

confidence: 99%

“…Those concerns are particularly relevant to the management of endangered host species (e.g. Least Bell's Vireo [Vireo bellii pusillus], Griffi th and Griffi th 2000; Yellow-shouldered Blackbird [Agelaius xanthomus], Wiley et al 1991, Lopez-Ortiz et al 2002.…”

mentioning

confidence: 99%

Parentage Without Parental Care: What to Look for in Genetic Studies of Obligate Brood-Parasitic Mating Systems

Hauber

Dearborn

2003

The Auk

View full text Add to dashboard Cite

show abstract

Increasing nest success in the yellow-shouldered blackbird Agelaius xanthomus in southwest Puerto Rico

Cited by 14 publications

References 6 publications

Impact of Shiny Cowbird and botfly parasitism on the reproductive success of the globally endangered Yellow CardinalGubernatrix cristata

Impact of Shiny Cowbird and botfly parasitism on the reproductive success of the globally endangered Yellow CardinalGubernatrix cristata

Ecology and Management of Shiny Cowbirds (Molothrus bonariensis) and Endangered Yellow-Shouldered Blackbirds (Agelaius xanthomus) in Puerto Rico

Parentage Without Parental Care: What to Look for in Genetic Studies of Obligate Brood-Parasitic Mating Systems

Contact Info

Product

Resources

About