Buscar
Mostrando ítems 21-30 de 108
Egg pecking and puncturing behaviors in shiny and screaming cowbirds: effects of eggshell strength and degree of clutch completion
(Springer, 2017-04)
Abstract: Shiny cowbirds (Molothrus bonariensis) are generalist brood parasites that use hosts varying in body and egg size. On the contrary, screaming cowbirds (M. rufoaxillaris), which are larger than shiny cowbirds, are ...
High frequency but low impact of brood parasitism by the specialist Screaming Cowbird on its primary host, the Baywing
(Csiro Publishing, 2014-05)
Brood-parasitic cowbirds (Molothrus spp.) exploit the parental care of other species (hosts) that raise their offspring. Parasitism by cowbirds reduces host reproductive success in several ways and quantifying such costs ...
Non-mimetic shiny cowbird nestlings escape discrimination by baywings in absence of host nest mates
(Springer, 2019-09)
Nestlings of obligate brood parasites must obtain resources from heterospecific hosts that are attuned to the solicitation behaviours of their own progeny. Failing to match the appropriate stimuli may result in suboptimal ...
Reproductive success of the specialist brood parasite Screaming Cowbird in an alternative host, the Chopi BlackbirdÉxito reproductivo del parasito de cría especialista Molothrus rufoaxillaris en un hospedador alternativo, Gnorimopsar chopi
(American Ornithologists' Union, 2014-10)
The Screaming Cowbird (Molothrus rufoaxillaris) is the most specialized brood-parasitic cowbird, relying almost entirely on the Bay-winged Cowbird (Agelaioides badius) as host. Recently, Screaming Cowbirds have expanded ...
Shiny cowbirds share foster mothers but not true mothers in multiply parasitized mockingbird nests
(Springer, 2014-04)
Obligate brood parasitic birds, such as cowbirds, evade parental care duties by laying their eggs in the nests of other species. Cowbirds are assumed to avoid laying repeatedly in the same nest so as to prevent intrabrood ...
Genetic patterns of repeat and multiple parasitism by screaming cowbirds, a specialist brood parasite
(Academic Press Ltd - Elsevier Science Ltd, 2020-09)
Avian brood parasites lay their eggs in the nests of other species, leaving the hosts to care for the parasitic offspring. The bookkeeping hypothesis predicts that, in order to reduce competition between parasitic nestlings, ...
Roosting behaviour is related to reproductive strategy in brood parasitic cowbirds
(Wiley Blackwell Publishing, Inc, 2018-10)
Shiny Cowbirds Molothrus bonariensis and Screaming Cowbirds Molothrus rufoaxillaris are closely related brood parasites but the former is socially polygynous or promiscuous and an extreme host generalist, whereas the latter ...
Red-crested cardinal defences against shiny cowbird parasitism
(Brill Academic Publishers, 2012-04)
Avian brood parasites reduce the reproductive success of the host, which favours the evolution of antiparasitic defences, such as aggression towards parasites or rejection of their eggs. The red-crested cardinal, Paroaria ...
Differences in morphology and colour pattern of shiny cowbird (Molothrus bonariensis) eggs found in nests of two hosts
(Wiley Blackwell Publishing, Inc, 2011-04)
Genetic differentiation among shiny cowbird (Molothrus bonariensis) females that use different hosts indicates that in this brood parasite, host use is not random at an individual level. We tested whether there exist ...
Planning host exploitation through prospecting visits by parasitic cowbirds
(Springer, 2017-01)
Abstract: We studied visits to potential host nests by two avian brood parasites, the host generalist shiny cowbird, Molothrus bonariensis, and the host specialist screaming cowbird, Molothrus rufoaxillaris, in the periods ...