Excerpts from Jim Conrad's
Naturalist Newsletter

Yellow-throated Warbler, DENDROICA DOMINICA

from the December 29, 2008 written at Mayan Beach Garden Inn on the Costa Maya, Quintana Roo, México
UBIQUITOUS YELLOW-THROATED WARBLERS
I've already mentioned how common Yellow-throated Warblers, DENDROICA DOMINICA, are as they overwinter in much of Mexico, including the Chiapas uplands and the Yucatán. They're common along our narrow sand road running the length of the low ridge between the ocean and the mangrove swamps. This week I got the picture of a friendly one right in front of the hotel, shown above.

Many warblers lose their bright colors when they come here to overwinter but Yellow-throateds don't seem to change much.

Yellow-throated Warblers nest in the US Southeast and a little beyond, and overwinter in most of eastern and southern Mexico, the Caribbean and much of Central America.


from the December 27, 2009 Newsletter issued from Hacienda Chichen Resort beside Chichén Itzá Ruins, central Yucatán, MÉXICO
WARBLER BENEATH A PALM FROND

This week as I passed beneath some Coconut Palms I heard a familiar sharp chipping sound, looked up, and saw the fast-moving little being shown below:

Yellow-throated Warbler, DENDROICA DOMINICA beneath palm frond

It was a Yellow-throated Warbler, DENDROICA DOMINICA, and he couldn't have been more at home, for his species is known to have a passion for palms when he's down here, though up north he tends to prefer the tops of pines and Sycamores.

The picture could be sharper but mainly I wanted to share with you the feeling of the moment, not anything you need a particularly sharp view of to appreciate. The feeling was of a small, nervously flitting, silhouetted little critter moving across palm fronds like a musical note bouncing up and down across lines of music while a song is being sung about light, fresh air, and glowing, living hope.


from the December 27, 2009 Newsletter issued from Yerba Buena Clinic near Pueblo Nuevo Solistahuacan in Mexico's southernmost state Chiapas
YELLOW-THROATED WARBLER IN THE CIBER

Last Monday as I issued last week's Newsletter a Yellow-throated Warbler, DENDROICA DOMINICA, landed in the ciber's door and hopped across the muddy, tiled floor to within a foot of my feet. With his yellow throat, white eyebrow and black mask, his identify was unmistakable.

During my Mississippi hermit days, Yellow-throats were among the first summer residents to arrive in early spring and all summer they kept high in the pines above my trailer, their repetitive calls loud and clear throughout the days. At Hacienda San Juan in the Yucatan they were common and conspicuous high among the fronds of Royal Palms along the entrance road. And now here was this one at my feet on a muddy floor in a cold, rainy Pueblo Nuevo ciber.

Could it sense that the entire upcoming week would be cold and rainy, and that it needed to take unusual risks to locate a dry place?

Back at Yerba Buena I looked up the Yellow-throat's winter distribution. It winters along the US Gulf Coast and the Caribbean, deep into Central America. A funny thing is that in Mexico it winters in the hot lowlands bordering the Gulf of Mexico, as well as here in the Chiapas and Guatemalan highlands, but it avoids the foothills. Why the hot lowlands and the chilly highlands, but not the middle elevations?

I'll bet the ice ages had something to do with this curious overwintering pattern. A wild guess might be that the lowland-wintering population results from migration patterns established after the second-to-the-last Ice Age, while the highland population, to avoid competition with the lowlanders, became established after the last Ice Age, or vice versa.