Notulae Ornitologicae Columbianae 4
Post date: May 8, 2016 4:47:55 PM
Abstract — Within a preliminary biodiversity diagnostic of Manizales municipality, Caldas department, we surveyed birds in the four zone life formations present in its territory between January-April 2001. In this manuscript we present the results of observations on population abundance and general distribution of various species of antpittas, genera Grallaria and Grallaricula, registered during this study. We used transect censuses and ad libitum observations. We report the presence of seven species, of which five were not registered previously; increasing the antpittas registered in the municipally to a total of nine species. All the species were registered above 2 100 m and exhibited some altitudinal overlap between 2 400-3 400 m. Rufous–crowned Antpitta (Grallaria ruficapilla) occupied the lowest zone of this altitudinal gradient (1 700-2 800 m), whilst Tawny Antpitta (Grallaria quitensis) occupied the highest part of it (3 500-3 800 m). We found marked differences in relative abundance and density among the seven species: the Rufous–crowned Antpitta had the highest values (2.2 ind/km y 0.4 ind/ha), and exhibited differences in relation to Moustached (Grallaria alleni), Brown–banded (Grallaria milleri), Tawny and Slate–crowned (Grallaricula nana) antpittas, while no differences were found in relation to Chestnut–naped (Grallaria nuchalis) and Rufous (Grallaria rufula) antpittas; Tawny Antpitta exhibited the lowest values (0.3 ind/km and 0.06 ind/ha). Moustached, Brown–banded, Rufous and Slate–crowned antpittas presented the highest values of relative abundance and density in old secondary forest zones, highlighting the importance of this habitat. Nonetheless, these species can occupy other habitats like Alder plantations (Alnus acuminata) with dense undergrowth and young secondary forests. Additionally, Rufous–crowned Antpitta was observed using secondary forest borders and Alder plantations, clearings and earlier successional stages, while Tawny Antpitta occupied only secondary bushes and shrubs. Our results identify Manizales, especially the Rio Blanco Watershed and adjacent forests, as an important region for the conservation of this little-known and vulnerable neotropical bird group. This paper contributes to the first objective of the national strategy for bird conservation, which is: “develop an information system that permits the study and monitoring of Colombian bird populations”.
Keywords — Grallaria and Grallaricula; distribution; abundance; density; habitats; Manizales
Notulae Ornitologicae Columbianae 4 – PDF
Supplementary material – PDF