Breeding

T. Schulenberg (pers. comm.) found two nests of Puna Thistletail in October at Valcón, department of Puno, Peru. Both nests were domed structures concealed with dense clumps of grass at the paramo/elfin forest ecotone (see the location of one nest in Habitat). One nest was about 40 cm above the ground, and was partially supported by a small slender bush. The nest was faced the edge of elfin forest, and was only ca 1 m from the forest edge. A "shelf" of flattened grass entended out of the entrance to the nest, and several twigs were laid this platform, ca 15 cm from the entrance to the nest. The nest contained two young on 6 October, which exited the nest when the nest was disturbed.

A second nest was found at the same locality on 10 October. This nest was in a similar setting: ca 80 cm above the ground in a clump of bunch grass, facing the edge of elfin forest, was ca 2 m from the edge of elfin forest, and again was partially supported by a small slender bush. This nest also had a "shelf" of flattened grass in front of the entrance to the nest, but this platform did not include any sticks. The nest contained two eggs.