Biologia reprodutiva de Taraba major (Aves, Thamnophilidae) na região do Pirizal, Porção Norte do Pantanal, Mato Grosso, Brasil

Abstract

O objetivo deste estudo é descrever aspectos da biologia reprodutiva de Taraba major tais como período reprodutivo, ninhos, ovos, ninhegos, tamanho de ninhada, período de incubação e permanência dos ninhegos no ninho. Os dados foram coletados durante as estações reprodutivas de 2009 e 2010, na fazenda Retiro Novo, município de Poconé, Pantanal, Mato Grosso, Brasil. A procura dos ninhos ocorreu de forma ativa e através da observação dos adultos transportando material para o ninho ou alimento para o filhote. Os ninhos foram visitados com intervalos de três a quatro dias. Foram monitorados 51 ninhos ativos. O período reprodutivo da espécie estendeu-se de outubro a dezembro. O tempo médio de construção dos ninhos foi de 06 ± 1,6 dias (n = 08). Os ovos são de formato ovóide, esbranquiçados com manchas marrons espalhadas por toda sua extensão. A massa, comprimento e largura média dos ovos foram 6,1 ± 0,5 g, 26,8 ± 1,5 mm, 19,5 ± 1,7 mm, respectivamente (n = 74). O tamanho da ninhada variou de dois (n = 13) a três (n = 1) ovos. Ambos os sexos constroem o ninho e revezam na incubação. O tempo médio de incubação foi de 15,5 ± 1,7 dias (n = 08), e a permanência dos ninhegos nos ninhos de 13,2 ± 1,6 dias (n = 08).

Nesting behavior of male and female Undulated Antshrikes (Frederickena unduliger)

“…The nestling period of Undulated Antshrikes in our study was 13 d, similar to those of other larger species (e.g., Great Antbirds, 12–13 d; Skutch , Sheldon and Greeney , Lara et al. ) and longer than those of smaller species of antbirds (8–12 d; Skutch , Zimmer and Isler , Schwartz ). This difference between large and small thamnophilids suggests that allometric relationships play an important role in determining the duration of nestling periods, but other factors such as rates of nest predation or longevity could also be important factors (Martin et al.…”

“…High rates of nest predation in combination with longer lifespans may favor selection for smaller clutches in songbirds that breed in tropical forests (Skutch 1985, Boyce et al 2015. Similarly, the color of the eggs of Undulated Antshrikes in our study, white with purplish hairlines and spots, concentrated at the larger end, matches that of the eggs of the two other species in the genus Frederickena (Haverschmidt andMees 1994, Greeney et al 2012) as well as the eggs of other antshrikes (von Ihering 1900, 1914, Oates and Reid 1903, Skutch 1969, Greeney et al 2004, Lara et al 2012.…”

“…The suspended open-cup nests of Undulated Antshrikes in our study were similar to the nests of most species in the family Thamnophilidae (Zimmer and Isler 2003). Similar nests have been described for other species in the genus Frederickena and in the related genera Batara, Cymbilaimus, and Taraba (Skutch 1969, Hilty and Brown 1986, Zimmer and Isler 2003, Greeney et al 2004, Lara et al 2012). Using dark fibers to form a thin wall in nests has also been reported for other species in the genus Frederickena (Haverschmidt andMees 1994, Greeney et al 2012).…”

“…, , Lara et al. ). Using dark fibers to form a thin wall in nests has also been reported for other species in the genus Frederickena (Haverschmidt and Mees , Greeney et al.…”

Full Issue

“…In these areas, Squirrel Cuckoo was observed in areas of dense vegetation, such as edges of primary and secondary forests, and at river and wetland margins. When an active nest was found, it was visited every 3-4 days, or every second day near hatching or fledging (Lara et al 2012). When the exact date of fledging or hatching could not be determined, we recorded it as the median date of the two most recent visits (Dudley & Saab 2003).…”