Reproduction of the Atlantic Forest endemic star-throated antwren, Rhopias gularis (Aves: Thamnophilidae)

Abstract

The Thamnophilidae are one of the most speciose Neotropical bird families, yet aspects of their natural history remain poorly documented. Here we provide information on breeding phenology, the length of incubation and nestling periods, parental care, and nesting success of the Star-throated Antwren, Rhopias gularis, an Atlantic Forest endemic. The data are discussed in light of life history theories. We found 27 active nests during two breeding seasons (2013/2014 and 2014/2015) at Carlos Botelho State Park in southeastern Brazil. Nesting activities were observed from September to January. Incubation and nestling periods lasted 16.8 ± 0.6 and 11.0 ± 0.86 days, respectively, as with most other antbirds. Males and females shared equally in incubation and nestling provisioning. The small clutch size of two eggs is that most commonly found in tropical birds and is hypothesized to have evolved due to increased nest predation rates. However, our data was not consistent with this hypothesis as the nest survival probability was high (57%). This is one of only a handful of studies that provide comprehensive information on the breeding biology of a Thamnophilid species in undisturbed habitat.Keywords: breeding phenology, life history, nesting behavior, nesting success, parental care.Reprodução da choquinha-de-garganta-pintada, Rhopias gularis (Aves: Thamnophilidae), uma espécie endêmica da Mata Atlântica Resumo A Família Thamnophilidae compreende as diversas espécies de chocas e papa-formigas e compõem um dos maiores grupos de aves neotropicais. Apesar do elevado número de espécies, aspectos da história natural permanecem pouco documentados. No presente estudo são fornecidas informações sobre fenologia reprodutiva, duração dos períodos de incubação e permanência dos filhotes no ninho, cuidado parental e sucesso reprodutivo da choquinha-de-garganta-pintada, Rhopias gularis, endêmica da Mata Atlântica, enfocando teorias de história de vida. Foram encontrados 27 ninhos ativos durante duas temporadas reprodutivas (2013/2014 e 2014/2015) no Parque Estadual Carlos Botelho, no sudeste do Brasil. Atividades de nidificação foram observadas de setembro a janeiro. Períodos de incubação e permanência dos filhotes nos ninhos duraram 16.8 ± 0.6 e 11.0 ± 0.86 dias, respectivamente, sendo similares aos de outras chocas e papa-formigas. Machos e fêmeas dividiram as funções de incubação e alimentação dos ninhegos em taxas similares. As ninhadas de dois ovos seguem o padrão mais comum para Passseriformes tropicais, mas os dados apresentados não se mostraram consistentes com a hipótese de que a evolução de ninhadas menores está relacionada às altas taxa de predação de ninhos nesta região, uma vez que foi observada alta probabilidade de sobrevivência (57%). O presente estudo é um dos poucos a proporcionar informações abrangentes sobre a biologia reprodutiva de um Thamnophilidae em uma área preservada.Palavras-chave: fenologia reprodutiva, história de vida, comportamento de nidificação, sucesso reprodutivo, cuidado parental.

First complete description of nest, eggs, and nestlings of the Squamate Antbird, Myrmoderus squamosus (Aves: Thamnophilidae)

“…Antbird in skin, bill, and rictal flange coloration, including the noticeably whitish feet. Biparental sharing of the duties incubation and nestling attendance is pervasive among the typical antbirds (Skutch 1969, Greenberg and Gradwohl 1983, Zimmer and Isler 2003, although it has been properly quantified only a few times (Perrella et al 2017). During our observations we confirmed biparental attendance in the Squamate Antbird for both incubation and brooding, a behavior also observed in M. loricatus and M. ruficauda (Buzzetti andBarnett 2003, Studer et al 2017).…”

“…Clutch sizes consisted of two eggs in the previous nests reported for the Squamate Antbird (Von Ihering 1900, Nehrkorn 1910, Schönwetter and Meise 1967, and also in all of the nests reported for the other Myrmoderus: M. ferrugineus (n = 1 nest), M. ruficauda (n = 42 nests), and M. loricata (n = 1 nest) (Stratford 2000, Buzzetti and Barnett 2003, Studer et al 2017, matching the general pattern found for tropical forest passerines (Jetz et al 2008), including other Thamnophilidae found at similar latitudes (Roper 2005, Perrella et al 2017. The clutch of a single egg found for one of our nests should be viewed with caution, as we were unable to confirm if only one egg was laid or if it could have resulted from a partial nest predation.…”

Nest, eggs and nestling description of the Silvery-flanked Antwren Myrmotherula luctuosa (Pelzeln, 1868) in the Atlantic Forest of northeast Brazil

“…During the reproductive activity, it was observed that both the female and the male participated in the incubation of the eggs (Fig. 2), and fed the nestling, like observed in other Thamnophilidae, such as C. melanaria ( Pinho et al 2006), H. maculicauda (Pinho et al 2006), T. pelzelni (Silva & Carmo 2015) and R. gularis (Perrella et al 2017). This is the first study to present information about the reproductive biology of the Silvery-flank Antwren M. luctuosa.…”

“…The young fledged with 11 days, but it could have occurred early due to the manipulation to obtain its measurements. Other species of Thamnophilidae showed similar nestling periods, such as C. melanaria (10 days; Pinho et al 2006), H. maculicauda (11 days;Evangelista 2008), Rhopias gularis (11 days;Perrella et al 2017) and Taraba major (13 days; Lara et al 2012).…”

Ecology and behavior predict an evolutionary trade‐off between song complexity and elaborate plumages in antwrens (Aves, Thamnophilidae)

“…Consequently, in this scenario, sexual dimorphism likely resulted from a form of social selection (West-Eberhard 1983, 2014Lyon and Montgomerie 2012) that acts on recognition during parental care of males by females, and vice versa, and by natural selection posing sex-specific pressures during parental care (Martin and Badyaev 1996;Owens and Hartley 1998). This idea is supported by assorted data on breeding biology suggesting that differential parental care is prevalent in sexually dichromatic antbird species, such as Formicivora acutirostris (Reinert 2008), Myrmotherula axillaris (Skutch 1969), Taraba major (Sheldon and Greeney 2008;Skutch 1969), Microrhopias quixensis (Greenberg and Gradwohl 1983;Skutch 1969), Gymnocichla nudiceps (Bradley 2008;Skutch 1969), Hylophylax naevioides, Poliocrania exsul (Rompré and Robinson 2008;Skutch 1969), Thamnophilus caerulescens (Oniki and Willis 1999), and Hafferia zeledoni (Caicedo and Londoño 2017), whereas it is absent in the sexually monochromatic Rhopias gularis (Perrella et al 2017). Regarding vocal communication, there is evidence of social selection in the genus Hypocnemis by the use of songs and calls in both sexes to defend territory annually and maintaining pairs together (Tobias et al 2011).…”