Breeding in the gray-headed tody-flycatcher (Aves: Tyrannidae) with comments on geographical variation in reproductive traits within the genus Todirostrum

ABSTRACT

The gray-headed tody-flycatcher Todirostrum poliocephalum is a passerine endemic to the Atlantic Forest of Brazil. We describe the nest and nesting behaviour of this species and investigate geographical variation in breeding traits in the genus using data from the literature, museum collections, and citizen science projects. We located 21 nests of the gray-headed tody-flycatcher, 13 of which we monitored. Nest height above the ground averaged 3.3 ± 3.4 m (n = 21). Nests were built over a 16.8 ± 5.6-day period (n = 6) by both adults. Clutch sizes ranged from two to three eggs, with a mean of 2.9 ± 0.3 eggs (n = 10). Eggs measured 16.6 ± 0.5 × 12.0 ± 0.5 mm (n = 23) and weighed 1.1 ± 0.1 g (n = 19). Mean incubation period was 17 days (n = 3) and mean nestling period was 15.5 days (n = 2). Apparent reproductive success was 30.8%, with predation being the primary cause of nest failure (46.1%). Mayfield’s reproductive success was 25.9%, and daily survival rates for eggs and nestlings were 0.957 and 0.971, respectively. Clutch sizes increased with latitude, but temperature and precipitation seasonality had very low importance in explaining clutch size variation.

KEYWORDS:

• Atlantic forest
• breeding biology
• life history
• Neotropical birds
• reproductive success

Acknowledgements

We thank the following institutions and their staff for kindly allowing us to study the specimens under their care: AMNH, COMB, IAVH, MNHN, MNRJ, MPEG, MZUSP, NBCN, NHMUK, NMSZ, NMW, USNM, WFVZ and ZMB. Instituto Chico Mendes de Conservação da Biodiversidade provided the permits (ICMBio 23439-1). Campus Florestal of the Universidade Federal de Viçosa allowed us to conduct this study in the area under their care. We thank Gustavo Martins and Luana Ferreira for their help during fieldwork. Andre Moncrieff and an anonymous reviewer provided constructive criticism on an earlier version of the manuscript.

Disclosure statement

No potential conflict of interest was reported by the authors.

Supplementary material

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Additional information

Funding

This work was supported by the Conselho Nacional de Desenvolvimento Científico e Tecnológico – CNPq [grant numbers 305401/2014-9, 473281/2013-9 and 305458/2014-0]; Fundação de Apoio à Pesquisa do Distrito Federal – FAP-DF [grant number 0193.000839/2015]; Fundação Arthur Bernardes – FUNARBE (FUNARPEQ 2012), Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES-PNPD); and Fundo Nacional de Desenvolvimento da Educação – FNDE.