Wednesday, January 27, 2016

Winter Mexican Tour Y2K16, Day 5: Ant Swarm!

Just on the south slope of Cerro San Juan, the nerds walked up a side road to see what they could find. Quickly, they hit a solid mixed flock. Hermit Warblers were very confiding and a nice trip bird; bizarrely, this was a life bird for Stilt, which enraged Dipper Dan. We all still wonder how she could have waited so long to see one; she wept openly and without remorse (a history she will no doubt attempt to revise), while Dipper Dan screamed at her in anger. Flycatcher Jen said nothing, plotting her next move to draw more attention to herself. Don Francisco contemplated all the money he was not spending by being in the middle of a Mexican forest. I, the birder philosopher-king, passed judgement on all of them, bitterly telling them they were doing it wrong.

The birds in this flock were unusually confiding. They wouldn't leave; it was a sedentary flock...the kind of flock dreams are made of. This Hammond's Flycatcher anchored it from a fenceline.

Finally, the five gringo idiots realized why the flock wasn't going was sitting on top of an army ant swarm! Massive columns of ants marched across the road, while the birds lurked just overhead, ready to grab insects flushed by the deadly swarm. This heavily-armed caterpillar was found in the midst of the ants, not giving a fuck. It's long, protective hairs repelled ant attacks with great efficiency; it was an unusual addition to one of the ant formations it had become swept up with.

Hepatic Tanagers were quite common during out trip, and were particularly keen on taking advantage of the ant swarm.

Can a bird be both red and subdued? Let this question cause you pain and heartache no more, for the answer is a male Hepatic Tanager.

Confiding bird. I think I like Hepatic Tanagers more now.

The star of the flock was this crippling male Flame-colored Tanager; this species never ceases to melt face.

Different members of the flock would often line up on barbed wire fences, as the ants would travel directly beneath them. This led to a number of amusing combinations of birds sitting in close proximity to each other. Here is the Flame-colored and the female Hepatic.

Painted Redstart (Whitestart) and pineish flycatcher.

A couple Ivory-billed Woodcreepers added a bit of tropical flavor to the flock, which otherwise contained a lot of species that make it to southeast Arizona.

Finally we left the ants and headed downhill in search of new, non-sedentary flocks and other birds. This Blue-throated Hummingbird was the first of the trip.

White-throated Thrushes were encountered on the regular; at least they are more interesting to look at than Clay-colored Thrushes.

Red-headed Tanager was the final group lifer of the day; we found a flock eating coffee berries right next to the road on the way down the road. Crippling little bastards. Getting these birds this afternoon turned out to be critical, because we didn't see any for the rest of the trip!

Pine Flycatchers turned out to be pretty common in higher elevations during this trip. How do I know this? Empids in Mexico are bizarrely cooperative.

Here is a female Mexican Woodnymph; we found this highly range-restricted species in multiple locations. Too bad that luck didn't carry over into many other species of hummingbirds.

Cerro San Juan was fantastic birding; if you are so inclined, our eBird checklist is right here.


  1. Did you see any other Empids? Dusky or Hammond's? White-throated or Gray? Any at all?

    1. Trip empids were Buff-breasted, Dusky, Hammond's, Least, Pine, Western, Willow, White-throated