Demography and Populations

Measures of Breeding Activity

Too few data exist on nests and associated activity to assess how song rates or male territorial behavior vary across seasons.

Life Span and Survivorship

There is no information of life span, but mean annual survivorship of Black-faced Antthrush at Parque Nacional Soberanía, Panama, was estimated at 0.42 ± 0.07 SE (Karr et al. 1990). A study of the effects of Hurricane Iris in Belize suggested that less than a third of individual antthrushes banded before the hurricane were alive after the hurricane (Johnson and Winker 2010).

Mortality, Disease, and Parasites

Little information is available on disease, although microfilariae blood parasites have been detected in the species (Galindo and Sousa 1966, Benedikt et al. 2009), as has Plasmodium (Mijares et al. 2012), the St. Louis encephalitis virus (Santos et al. 2006), and a potentially zoonotic cacipacore virus (Weissenböck et al. 2010). Not surprisingly, antthrushes are afflicted with bird lice, in this case lice of the genus Formicaricola, which is specialized on the avian family Formicariidae sensu stricto (Carriker 1957, Price and Clayton 1995). Both chewing lice (Phthiraptera; Sychra et al. 2006) and chigger mites (Trombiculidae; Arnold 1970, Stekol'nikov et al. 2007) also have been recorded. With regard to endoparasites, there is a single instance of a trematode of the family Brachylaimidae (Tallman and Tallman 1994).

Population Regulation

How population size is regulated is an open question, but measured population densities vary markedly. Densities generally range from 3.9 birds/100 ha (Amazonian Brazil; Stouffer 2007) to 7.8 birds/100 ha (French Guiana; Thiollay 1994), with minimum and maximum values being 1.2 birds/100 ha and 15.0 birds/100 ha, respectively (Stouffer 2007).