Tag: slate-blue seedeater

For more than 1,000 years, ancient people built terraces, dams, pyramids and mounds in central Mexico.

One of these sites is called Monte Albán, and it was carved from the mountain outside Oaxaca.

Archaeologists have made countless discoveries about the history of the people who once called the site home, but now, it is the center of a different kind of discovery.

A songbird has been found at Monte Albán for the first time.

Researchers placed tall nets around the site to capture birds as part of a biodiversity project in June 2023, according to a study published Oct. 13 in the peer-reviewed journal Check List.

They waited for birds to collide with the net so they could be identified and catalogued, according to the study.

Then, “slate-blue” and “cinnamon”-colored birds became wrapped up in the mesh.

The birds were identified as Amaurospiza concolor relicta, the male and female of the species, or the slate-blue seedeater, researchers said.

“The male had the characteristic darker blue color of A. concolor, specifically slate-blue all over its body and wing coverts (small feathers at the base of the flight feathers), while the remiges (large flight feathers) exhibited a black edge with a slate-blue border,” researchers said. “The rectrices (tail feathers) were predominantly blackish with an external wash of slaty blue.” (

The sides of the face, ear openings and throat were more blackish, while the forehead of the male birds were “sky-blue” darkening to a deeper shade toward the base of the crown, according to the study.

The females, however, were completely different.

“The female had cinnamon-brown upperparts and ochraceous-tawny underparts. The remiges were dusky brown with cinnamon-brown edges,” researchers said.

Slate-blue seedeaters are a part of a group of birds called passerines, or birds that have the correct feet structure to be able to perch on ledges, a feature that unites all songbirds.

They are also from the family Cardinalidae, which includes cardinals, tanagers, grosbeaks and buntings, according to the Cornell Lab of Ornithology.

Aside from their coloration, the seedeaters stand out from other related birds because of their “robust, conical bill,” according to the study

The species is considered a “bamboo specialist,” according to Cornell, and eats bamboo seeds in stretches when all the plants release their seeds in a synchronized event.

“It is this concentrated and easy-to-find food that the seedeaters are after,” according to Cornell. “Due to this close association with these plants (the birds are) usually considered a very local, rare species and difficult to spot throughout its distribution.”

The specific slate-blue seedeaters are thought to be restricted to the Pacific slope and interior region of southwestern Mexico, with no previous records in the Valles Centrales region of Oaxaca, until now.

“Consequently, our documented observation represents the first confirmed record of A. concolor relicta in this area, thereby extending the known southeastern boundary of its year-round range,” researchers said. “After the capture of these individuals … four subsequent citizen-science observations … support our finding.”

The species is considered “endangered” in Mexico, according to the study.

Monte Albán is in southwestern Mexico.

The research team includes Daniel F. Díaz-Porras, Irving de J. Morales-Leal and Jaime M. Calderón-Patrón.