Excerpts from Jim Conrad's
Naturalist Newsletter

from the July 18,, 2010 Newsletter issued from Hacienda Chichen Resort beside Chichén Itzá Ruins, central Yucatán, MÉXICO

As I walked across the open area in front of the workshops returning a wheelbarrow one of the fellows asked if I wanted to see some nestlings. He pointed at a Sabal Palmetto (fan palm) trunk very shaggily mantled with the dried-up bases of old frond petioles, but I saw nothing. He had to walk up to the tree and point to exactly where the nest was before I saw it, and you can see it snugly beneath an old petiole base below:

nest of Yellow-throated Euphonia, EUPHONIA HIRUNDINACEA

The petiole base very nicely sheds rain from our almost daily afternoon showers or downpours. A close-up showing what the arriving parents see is below:

altricial nestlings of Yellow-throated Euphonia, EUPHONIA HIRUNDINACEA

These are Yellow-throated Euphonias, regularly seen around the Hacienda. Euphonias are small tanagers and are known to build globular nests with side entrances exactly as shown in the nest picture. The species is distributed from eastern Mexico to western Panama.

As I was knocking around taking the above pictures the nestlings, even though they had somewhat glassy-looking eyes open, remained in plain view begging, apparently depending on the theory that any activity without signified a parent approaching with food. Later that day, however, when I went to check on them, my movements caused them to cower out of sight in the nest's bottom. Just in those few hours, had they matured enough to change their behavior so drastically?