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Extra-pair paternity (EPP) appears to be widespread in passerine birds, but few studies have focused on suboscine species, and therefore it is unclear if this generalization can be extended to this group. In this study, we document high rates of EPP in a socially monogamous, suboscine passerine, the Scissor-tailed Flycatcher (Tyrannus forficatus) in southwest Oklahoma in the summers of 2009-2011. Averaged across years, EPP occurred in 66% of nests in our study population and accounted for 49% of all nestlings. EPP rates were variable (50-88%), but did not differ significantly among years or between two study sites. Our review of the literature yielded EPP data for only 11 other species of suboscines (0.7% of total), which we compared to EPP rates for the 83 oscine species (1.9% of total) reported in Spottiswoode and Moller (2004). EPP was as common and variable in suboscines (21.7% of young) as oscines (17.5% of young). Our study adds to our knowledge of mating systems in the understudied suboscine group, but further sampling of suboscines should be a priority, as they comprise a quarter of all passerine species and comprise a large fraction of passerines in tropical regions. Received 26 January 2015. Accepted 16 August 2015. Key words: EPP, mating systems, oscine, Tyranni, Tyrannidae, Tyrannus forficatus., The mating systems of >90% of bird species are classified as socially monogamous (Griffith et al. 2002), where a prolonged pair bond between a male and a female is established [...]

The Red-winged Blackbird (Agelaius phoeniceus', redwing) is a commonly used accepter host species that incubates eggs and cares for nestlings and fledglings of the obligate brood parasitic Brown-headed Cowbird (Molothrus ater; cowbird). This host species, however, may reduce the risk of parasitism with a frontloaded antiparasite strategy in which it attacks parasites that approach active host nests. To test this ffontloaded parasite-defense hypothesis (FPDH), we presented taxidermic models of a female Northern Cardinal (Cardinalis cardinalis), which represents no threat to redwings, a male cowbird, which cannot lay a parasitic egg, and a female cowbird, together with species- and sex-specific vocalization playbacks for 5 min. We conducted these presentations at 25 active redwing nests at Newark Road Prairie in south-central Rock County, Wisconsin, USA, where 18% of redwing nests were parasitized by cowbirds in 2015. As predicted by the FPDH, the female cowbird mount elicited the most aggressive responses and the female cardinal mount the least aggressive, as measured by number of times more than one male redwing responded and number of times the male host attacked the mount, and by Principal Component Analyses yielding the highest redwing aggressive behavior and intimidation scores. Contrary to the predictions of FPDH regarding the success of nest defense behaviors, male redwings responding at naturally parasitized nests were significantly more likely to attack the mount than males with nests that were not parasitized, although our sample size was small. We also compared our results with those of a study using the same methods in New York State where cowbird parasitism was rare. Redwings in Wisconsin were more aggressive toward the female cowbird mount than redwings in New York. Red-winged Blackbirds appear to frontload their antiparasite defenses, but the success of those defenses depends on individual and population-level experience with parasites. Received 20 October 2015. Accepted 21 January 2016. Key words: Agelaius phoeniceus, antiparasite behavior, brood parasitism, Brown-headed Cowbird, Molothrus ater, Redwinged Blackbird., About 1 % of bird species are obligate brood exclusively on host species to build nests, incubate parasites, whose reproductive strategy depends eggs, and care for nestlings and fledglings (Davies [...]

Cases of interspecific parental care are rare and pose an evolutionary puzzle. We report a male House Wren (Troglodytes aedon) regularly provisioning Northern Cardinal (Cardinalis cardinalis) nestlings in a nest located near his own. The male wren continued to provision the cardinal nestlings after his own nestlings hatched, and provisioned the cardinal nestlings more than his own nestlings during the time that their nestling periods overlapped. The adult cardinals also provisioned their own nestlings. After the cardinal chicks fledged, the male wren provisioned only his own nestlings. This is most likely a case of nonadaptive misdirection of parental behavior on the part of the wren. That the wren provisioned both nests while both were in the nestling stage, but provisioned only the wren chicks as fledglings, may suggest that kin recognition in House Wrens is mutable rather than fixed. However, this behavior is also congruent with observations of polygynous male House Wrens transferring parental care from primary to secondary broods upon the fledging of the primary brood. Received 24 September 2015. Accepted 12 January 2016. Key words: adoption, Cardinalis cardinalis, interspecific parental care, Troglodytes aedon., OBSERVATIONS A male House Wren (Troglodytes aedon) was first observed nest-building on 29 April 2015. He moved twigs into three nest boxes and two gourds in RS's yard in Virginia [...]

Reports of interspecific parental behavior are rare but widespread among avian taxa. We present the first known case of interspecific parental care by a Wood Thrush (Hylocichla mustelina) at a nest of the Veery (Catharus fuscescens), documented by video at a long-term study site in northern Delaware, USA. We provide data on nest chronology, quantify parental behavior, and describe a copulation event between the Wood Thrush and the female Veery that was captured on video. Despite incurring no obvious fitness benefit, the Wood Thrush provided significant and prolonged nestling care including more feeding attempts and sanitation maneuvers than either Veery. We propose that these observations are a consequence of the normal adaptive behavior of the recipient species. Received 27 March 2013. Accepted 29 July 2013. Key words: Catharus fuscescens, Hylocichla mustelina, interspecific parental care, Veery, Wood Thrush., Reports of interspecific parental care, when an adult of one species provisions the offspring of another, are rare yet sufficiently widespread among avian taxa so as to beg an explanation [...]

Our observations on the reproductive habits of the Slaty-backed Nightingale-Thrush (Catharus fuscater) were made at a single nest between 2-12 November 2009 at an elevation of 2,050 m, in the vicinity of the Yanyacu Biological Station and Center of Creative Studies (00[degrees] 36' S, 77[degrees] 53' W), 5 km west of Cosanga (Napo Province, northeastern Ecuador). During the first 3 days following hatching, the only adult which provisioned nestlings was a color-banded female. Beginning with day 4, however, we observed five other individuals bringing food to the nest, including three color-banded males, one unmarked male, and one unmarked individual presumed to be female. The last two birds and one of the banded males were sexed using morphological differences, the remaining banded individuals were sexed molecularly. Most (72%) of provisioning visits to 4-9 day old nestlings were made by the color-banded female which also incubated the eggs. Our observations suggest the existence of a potentially complex cooperative breeding system in Slaty-backed Nightingale-Thrush. Received 24 March 2014. Accepted 17 November 2014. Key words: Catharus fuscater, cooperative breeding. Slaty-backed Nightingale-Thrush., World-wide, more than 300 species of birds have been found to breed cooperatively, but among the ~140 species of thrushes (Turdidae), fewer than 5% have been reported to have helpers [...]