NATURAL HISTORY AND BREEDING BIOLOGY OF THE RUSTY-BREASTED ANTPITTA

ALINA M. NIKLISON; JUAN I. ARETA; ROMÁN A. RUGGERA; KARIE L. DECKER; CARLOS BOSQUE; THOMAS E. MARTIN

WILSON JOURNAL OF ORNITHOLOGY

WILSON ORNITHOLOGICAL SOC

Lugar: Tucson, Arizona, Estados Unidos; Año: 2008 vol. 120 p. 345 - 352

1559-4491

We provide substantial new information on the breeding biology of the Rusty-breasted Antpitta (Grallaricula ferrugineipectus ferrugineipectus) from 40 nests during four consecutive breeding seasons at Yacambú National Park  in Venezuela. Vocalizations are quite variable in G. ferrugineipectus. Nesting activity peaked in April when laying began for half of all nests monitored. The date of nest initiation pattern suggests this species is single-brooded. Both parents incubate and the percentage of time they incubate is high (87-99%) throughout the incubation period. The incubation period averaged 17.0 ± 0.12(SE) days, while the nestling period averaged 13.37 ± 0.37 days. G. f. ferrugineipectus has the shortest developmental time described for its genus. Time spent brooding nestlings decreased as nestlings grew, but was still greater at pin feather break day than observed in north temperate species. The growth rate constant based on mass (k  = 0.41) and tarsus length (k  = 0.24) was lower than the k for north temperate species of similar adult mass. All nesting mortality was caused by predation and overall daily survival rate was relatively low (0.94 ± 0.01[SE]) yielding an estimated 15% nest success.