Friday, January 30, 2009

Volcan Masaya

Yesterday afternoon, some of us students at the Laguna de Apoyo language school in Nicaragua went to Parque Nacional Volcan Masaya. This is an active volcanoe that had tourists running for cover as recently as 2001. The visit, though pleasant, was not without danger.

OK, so it didn’t happen to erupt during the 2 hours while we there, but even at rest, this volcano produces enough fumes to keep you from peering over the edge inside. We did this, very briefly, at the very end of our visit, wearing gas masks.

Visible in the depths through the smoke was a faint glow. I decided to keep my camera inside my backpack inside the minivan, and not get that photo. Figured it wasn’t worth risking damage to my optics.

After visiting the crater, we visited a couple of caves, one of which had a bunch of bats swirling around. We went inside the bigger of the two, where we were shown rock formations, one of which was supposed to resemble the face of the God of Darkness. Someone said it looked like Elvis, although I thought it looked really more like Gene Simmons, of Kiss. Everyone brings their own cultural references to these kinds of things, I guess. The bat cave was much narrower, so we only peered inside. Our guide asked us if anyone wanted to get photos, which he would take for this person from the best seat in the house. Sure, I said, I would appreciate that, and he proceeded to take a series of photos, including the one above. As will happen on such occasions, in the dark the camera accidentally got set to manual focus. This greatly reduced the possibility of me getting decent bat shots to those instances where the bat just happened to be flying in the fixed focal range.

Afterwards we went into town (Masaya) where every Thursday in the old market, dancers perform for tourists. The food was good and the dancing fairly entertaining, so all in all a nice afternoon and evening out.

Wednesday, January 28, 2009

Laguna de Apoyo

I’ve arrived at the Spanish language school FUNDECI/GAIA on the Laguna de Apoyo, about an hour and a half east of Managua, the capitol of Nicaragua. I’m here to improve my still quite modest Spanish skills. I’ve been traveling and working in Spanish speaking countries for a while now, and finally found an opportunity to focus on the language itself, rather than hoping to incrementally get a little better through prolonged exposure. The latter approach has gotten me to the point where I can get around on my own, ask people stuff I need and understand most of what they answer me. So that’s my starting point here. I now want to go beyond that to where I can have a conversation in Spanish about more than just the weather.

Plus, the birding isn’t too shabby here either.

I just got here, and I’ve seen and heard a handful of birds, including a first lifer: Pacific Screech Owl. They must be common here, last night I heard two around the house. This is an Orange-chinned Parakeet, a common species in much of Central America.

I spent three days on various buses from San Cristóbal de las Casas in Chiapas, Mexico, with stops in Guatemala City and San Salvador, and got here on practically no money at all. Parts of this journey I knew all too well: hey, there’s the police station where we got pulled over and got a ticket for having only one, not two reflecting triangles, a couple of months ago. A ticket I could only pay with mexican pesos, of little value to the Honduran police officer. Hey, that’s where they stopped us and needed to hear all about our project. That’s where we got gas.

Most of Guatemala was new for me. Between Guatemala City and the Salvadoran border, I saw forests blooming with orange flowers – three colors for as far as the eye could see: green mixed with orange, and blue.

Now I’m here in Nicaragua, at a place with a pleasant, relaxed international atmosphere. It's great to see people I met a few months ago at the Golden-cheeked Warbler workshop in Honduras again: Jeffrey, Aura and Pablo.

The food is great and the swimming in the lake here is quite fantastic.

This is a Hoffmann’s Woodpecker, the common Melanerpes woodpecker in these parts. This is a successful genus: wherever you go in North and Central America, there’s usually one of these species around, often quite abundant.

Saturday, January 24, 2009

On the road

Today a photo of one of the sixteen Golden-cheeked Warblers we encountered during these past five weeks. More than half – nine – were adult males. In this part of the winter range, adult males indeed appear to be more abundant than the other age/sex classes, although the fact that there is so much overlap in plumage characteristics between ages and sexes, muddles the issue somewhat. Adult males are distinctive, though.

Adult males are the first ones to return to the Texan breeding grounds in March, and generally arrive a week earlier than the females, in order to claim territories. The females, upon arrival, can then choose their mates on the basis of the quality of these territories, among other things. It makes sense for the males to winter closer to the breeding grounds, because an early arrival in good condition will give a male a competitive edge over males arriving later, or from further away.

That said, my own northbound migration will be delayed by more than a month, as I have an opportunity to improve my Spanish skills at a language school in Nicaragua. I will also be spending some time in San Salvador, working on the analysis and reporting of this Golden-cheeked Warbler study.

In an earlier entry, I mentioned the Panamericana, or Pan-American Highway. That’s where I’m headed next, south on this highway – which for the most part isn’t really a highway so much as a two-lane paved road connecting villages and towns, just like any other road around these parts. But it’s also a mythical road, an idea of a connection that transcends countries and borders, stretching across the American continent.

Next time more on that journey.

Thursday, January 22, 2009

Last flock

That’s right: this morning we described flock number 25 in Coapilla, and at the moment of writing (early evening) have just returned to Moxviquil (San Cristóbal), our home away from home. We’ll be here for a day or two to wrap up the administrative part of the field season, and then for me it’s on to greener pastures. More about that tomorrow.

Fittingly, our last flock had a Golden-cheeked Warbler. It also had a Magnolia Warbler (pictured above). And that’s where things get tricky. The tree where we saw the goldencheek in was 734 m from another tree where two days earlier we had seen an immature female type goldencheek in. That flock also had a Magnolia Warbler… Today’s goldencheek also wasn’t an adult male…

We saw it only for a couple of minutes early in the game, well enough to know what it was, and to note plumage details. This bird appeared to have more dark on the throat than that other individual, and I thought I saw black streaking in the olive upperparts, which the earlier bird didn’t have. Yet, a morsel of doubt lingered and that Magnolia Warbler certainly didn’t help to eliminate that!

I thought we were far enough away from that earlier flock, and continued to observe this flock. Its composition was sufficiently different: it didn’t have a Greater Pewee, which the other flock had; it had two Warbling Vireos, while the other flock had none; and it only had two Black-throated Green Warblers, while the other flock had four.

And it had a Nashville Warbler, also not found in that other flock. In winter, superficially similar to Magnolia Warbler, but with a clean yellow breast and a very different tail pattern. In this photo, even the slight rufous markings on the head are visible.

When we were done describing the flock, I decided to simply walk back to the other flock location, and see which birds we would find over there. That strategy worked fine one time in La Granada, when a similar situation presented itself.

However, as we walked the 700+ meters back, we encountered small numbers of birds here and there. Mostly Wilson’s Warblers, which are practically everywhere anyway, but also a Greater Pewee and a Townsend’s Warbler. Back at the first flock location, there were some birds, but not very many. Mostly Townsend’s Warblers.

I thought this was most unusual. We tend to think of flocks as more or less stationary; go back the next day and you’ll find all the same birds there. But is that really the case?

I said to field assistant Hector that I thought this was a riddle, wrapped in a mystery, inside an enigma.

But perhaps there is a key, I added.

What if these two flocks are siamese twins, a double star? What if they are really only one big flock with two centers, and a corridor between them – the trees planted along the road that connects the two locations – through which osmosis takes place?

As we walked back towards the village, for lunch along the Laguna Verde, we found another Magnolia Warbler. This was maybe 400 m from where I had seen the very first one on an afternoon stroll, and perhaps also 400 m from flock 1, but more than a kilometer from where we saw a Magnolia today, in flock 2. Hey, I said, I’m willing to believe there are two Magnolias, but three Magnolias – at this elevation – seems a stretch. Which one is this?

Wednesday, January 21, 2009

Location

Today we stayed close to Coapilla, figuring we’d able to find a Golden-cheeked Warbler at less than 2 hours’ walking distance. And indeed we did, almost immediately, only a few hundred meters outside the village. As the photo clearly shows, this was another ‘white-throated’ individual; in other words, not an adult male. The throat is actually not pure white, but rather yellowish on the chin and white mixed with sparse black lower on the throat. The upperparts were olive. I’d tentatively call it an immature female type, but see earlier postings for a discussion of ageing and sexing GCWA in the field.

The first two goldencheeks that we found here were more or less chance encounters outside the flocks we have described. This bird was a member of today’s flock, in which I identified 32 birds representing 19 species.

Of course there’s a standard cast of characters that make up the majority of the flocks here. Most mixed winter flocks here in Chiapas will have at least one Blue-headed Vireo, a few Townsend’s Warblers, one or more Wilson’s Warblers, a couple of Hutton’s Vireos, a Greater Pewee, a Slate-throated Redstart, maybe a Black-and-white Warbler, and a couple of Olive Warblers. Regularly, there are one or two woodcreepers involved – here it’s nearly always Spot-crowned – and a few woodpeckers, Blue-gray Gnatcatchers and an Empidonax flycatcher or two.

Birds that aren’t necessarily flock members but are common in pine-oak habitat here include Mountain Trogon, Brown-backed Solitaire, Acorn Woodpecker, White-eared Hummingbird, and Rufous-browed Peppershrike, among others. You cannot walk very far in these woods without encountering these species.

Many birds at our current and final field site, Coapilla, we also found at the four earlier sites. But the bird community here is subtly different from those earlier sites. Barred Antshrike for example we never encountered at the other sites – here it is common, we hear it all the time. Golden-olive Woodpecker, another example. Crescent-chested Warbler is common around San Cristóbal; here I don’t think we’ve even seen any. It’s probably a matter of elevation.

In today’s flock, we had a Magnolia Warbler, generally more common at lower elevations. We also had a beautiful adult male Golden-winged Warbler in the flock, also a bird more commonly found at lower elevations.

And we had no fewer than four Black-throated Green Warblers in today’s flock! That’s a bird that’s certainly more common here than around San Cristóbal. Two birds were adult males, one was a female, and one was an immature female type.

I wonder if that’s also an elevational thing. It might just be location, location, location. This spot is more southerly, along a mountain range that leads into the heart of the pine-oak ecoregion, where the species is common in winter.

Another difference with San Cristóbal: there I was one of many Europeans, here in Coapilla there is practically no tourism, and I stick out more. Kids stare at me, girls giggle, and everywhere we go, people want to know where we are from, and what we are doing here. I’m a curiosity.

Tuesday, January 20, 2009

On top of the world

Well, maybe not quite, but it felt that way a little this morning, as we got to the top of a mountain. The world below us was covered in clouds, it was probably a dull and dreary January day down there, but where we were, it was sunny and beautiful.

The elevation here is actually a little lower than around San Cristóbal, and it’s decidedly less cold around here, although the hour before sunrise can still be a bit cool. A little after 6 AM, local forestry official Pedro drove us 12 km out of town, to an area that had cloud forest on one side of the road, and – as we later discovered – very small tracts of remaining forest amid larger logged areas on the other. Unfortunately, this was not visible from the road, or we probably wouldn’t have gone there. I figured it was best to climb the mountain ahead of us – it would give us great views of the area, and once up there we would be able to judge which place held the most promise of encountering Golden-cheeked Warblers.

Once we got up there, all we saw were tiny plots with huge pines and slightly bigger plots with mostly sweet gum.

This is the red-leaved variety of sweet gum…

… and this is the yellow-leaved variety. This tree is usually associated with running or standing water nearby.

We hiked this mountainside for hours but encountered very few birds. Hummingbirds were the only ones really abundant here. Nasty creatures they are; I saw one dive-bombing a female Flame-colored Tanager. Eventually the tanager took cover among shrubs on the ground, where the hummingbird continued to harass it until it finally gave up. Yesterday we saw the same thing happening to a Townsend’s Warbler.

When we got to a patch of cloud forest, we decided to hike upslope in hopes of encountering warblers there, but all we found – besides the ubiquitous Wilson’s Warblers – was an Azure-hooded Jay, and a Resplendent Quetzal calling. We tried to look for the quetzal but never saw it. Later we heard a Collared Trogon, and as usual quite a few Mountain Trogons.

Three species of trogon is pretty cool when you’re out fun birding of course, but we were looking for mixed flocks and Golden-cheeked Warblers and weren’t finding them. Around 10:30 AM, we decided we’d better hike back to the road. I kept my ears open for any type of warbler chip, thinking a late-encountered flock would still be a good starting point for the next day.

Fairly close to the road, I heard a chip that to my ears was either a goldencheek or a black-throated green. Among the virens super-species, a Townsend’s Warbler chip is louder (and among them, males again louder than females), while a Hermit Warbler chip is softer. And sure enough, it was a male Black-throated Green Warbler. Thinking this was a good place to rest – after all, we had been hiking steep terrain almost continuously for over four hours – we sat down, and waited for other flock members to appear. There – another chip, sounds similar. Yes, another BT green, also a male. We observed these birds for a while, as they calmly and methodically foraged in sweet gum trees.

Then, as we got to the road, I heard another chip, and this time it was an adult male Golden-cheeked Warbler.

Here it is, feeding in a favorite tree species, Quercus sapotifolia, a type of encino oak. The bird is less heavily marked than most other males we’ve seen here, but, as I said to field assistant Hector, “it may not have much black, but everything that should be black on an adult male, is black”. Meaning, the throat was entirely black, including the chin, and also the upperparts were black. Most adult males have more black on the breast and sides, though. And the undertail coverts – to come back to an earlier posting – were clean white on this bird.

After this sighting, we walked the full 12 km back to town.

Coapilla

We’ve arrived at our last field site here in Chiapas for the current Golden-cheeked Warbler field season, this time a little further from ‘home base’ Moxviquil. We got here yesterday [see note below] by bus and taxi, altogether maybe three and half hours of traveling from San Cristóbal.

Coapilla is a small town, smaller even than Teopisca. It’s got one hotel that’s still partly under construction, and a few smaller outfits – posadas – that are essentially mom and pop operations. Not wanting to stay at a noisy construction site, we are now at “Rossy”, one of those smaller outfits, which appears to be run not so much by mom or pop but by the daughter, who cheerfully multitasks cooking duties with cleaning, laundry, dishes and various other tasks, while her relatives sit around watching TV or chatting. Pobrecita! I’m sure these relatives have nothing but the best of intentions for her. For example, almost right away, an enquiry was made into the marital status of the gringo. Technically not a gringo – although being European practically amounts to same thing – and certainly not independently wealthy, I am hardly worth their attention.

Bueno. The birding here certainly is good, as two life birds, a goldencheek and a surprise find all testify. Which lifers? Well, White-throated Swift, which was actually a bit overdue given the amount of time I have now spent birding the region. I don’t think this is a particularly rare species, it’s just that I had never seen one. Today we saw a group of four. The other lifer was Gray-collared Becard, a bird I didn’t expect to see here and in fact knew so little about, that when I saw it – and I saw it well – I didn’t even know what it was. Some kind of becard, was all I could come up with. The only becard I know well is Rose-throated, but this bird – a male – was much paler than that, a little smaller also, and had a lot of white on the wings, and a gray tail with a white edge and sides. This bird is nowhere common in its range, which comprises three geographically separated populations: in western Mexico, eastern Mexico, and Central America. There was a female Rose-throated Becard around as well. A little bigger and with a completely rufous tail, it wasn’t a female Gray-collared.

Regular readers of this blog have seen several posted Blue-throated Motmot photos by now, another bird that is supposed to be uncommon. We’ve encountered it now at three different sites and I wonder if it is really so uncommon here. It’s not a bird we actively search for, but occasionally stumble upon. I have never heard one vocalize, I usually just see it sitting quietly in a tree somewhere. They have a tranquil beauty and presence all of their own, and even without tail streamers they are still my favorite motmot (photo top).

Birds we see more often and hear practically all the time at most of our Chiapas field sites are Mountain Trogons.

The understory in the forest that we surveyed today had lots of flowers, and consequently lots of hummingbirds. This is a Ruby-throated Hummingbird.

Pelicans of course are common birds in pine-oak forests, often seen nimbly catching insects hidden away in needle clusters… No, wait a minute – that seems wrong.

This Brown Pelican was about the last bird I expected to see here, but there it was! I don’t think I’d ever seen one away from salt water. Maybe this bird – a young ‘un – got lost and found itself high in the mountains of Chiapas, looking for a place to fish. It circled for 10 minutes over La Laguna Verde, the local pond that serves as a centro ecoturístico, before it decided the pond was too small and moved on.

We saw birds there that fish on smaller prey, like these Least Grebes.

The goldencheek we found while scouting for future locations, after we had already described the first flock here. We’ll probably return there sometime in the days ahead, though not tomorrow. Tomorrow a local forestry official will take us to a part of the reserve that is a little too far to walk, but which apparently also has the Golden-cheeked Warbler among the members of its bird community.

Other warblers of note that we have seen here this first day are a Magnolia Warbler (generally more common at lower elevations), already three Black-throated Green Warblers (maybe more common here?) and a couple of Nashville Warblers, a rather uncommon species at the sites around San Cristóbal.

Note: we didn’t find any internet here in Coapilla the first few days, so it may take a while for these posts to appear on the blog.

Thursday, January 15, 2009

Thirteen ways of looking at a warbler flock

Contrary to where I said we would be in the previous post, we’re still in San Cristóbal. It now looks like we’ll be traveling to our last field site tomorrow, so we can start with field work there Saturday morning.

This extra day off gave me an opportunity for some casual birding around the house. I decided to look for the flock that a couple of days ago had three Golden-cheeked Warblers in it, in hopes of getting some halfway decent photos of these birds. That, alas, did not transpire. I was able to relocate the flock, and I did see one goldencheek in there (again the ‘white-throated’ individual), but photo ops were hardly better this time around and I was OK with getting a couple of shots of other flock members.

This is a Townsend’s Warbler of course, while the bird at the top is a Crescent-chested Warbler.

I found the flock just north of Pronatura’s Moxviquil visitor center, in exactly the same place as a couple of days ago. And again, they went up the hill to Dead Dog Hole. But as I casually looked through the flock, I ruminated on what constitutes a flock, who are its members and who are just passers-by, and how do you become a member? In this flock, which I assumed to be the exact same flock from two days ago, I found several birds not encountered previously. There was a Nashville Warbler, for example, an uncommon species around here; a Yellow-bellied Sapsucker (also not common); a Guatemalan (Northern) Flicker; and finally a Western Tanager, which I didn’t see but heard only. I certainly did not stay long enough with this flock to identify all of its members – after all, this was my day off – but I assumed the Townsend’s, Crescent-chested and Wilson’s Warblers, and the Blue-headed, Warbling and Hutton’s Vireos that I saw to all be the same individuals we observed two days ago. There were Bushtits also, dubious flock members. Previously, in earlier flocks, I had counted them in, because they seemed to go where everybody else was going. Lately, I’m not so sure. A notable absentee today was Greater Pewee, a vocal species that is among the easiest birds to identify in a flock. Where was it today? Did it perhaps also have a day off? Or take Dusky-capped Flycatcher, another vocal bird. Rarely seen but often heard at the edge of the flock, giving its wheezy call. Sometimes they seem to move with the flock, and sometimes they don’t.

Each morning, we look for flocks and when we find one, we describe it by noting its members. The next day, we move on to a different flock. With this approach, it is easy to get the impression that every flock you find is by and large composed of the birds you described as its members, and that the next day or the next week, that flock will be there in the same location, with the same members.

But I’ve wondered before just exactly how tight or loose these mixed species associations are anyway. Do the same flock members associate with each other throughout the winter in that same spot? Or is there some kind of osmosis going on, with birds casually entering and leaving the flock over the season? Do individual birds switch flocks occasionally; do they sometimes feed just by themselves?

Finally, more time also today to look for butterflies here, but all I found were very common species, like the Mexican Silverspot pictured above. Still, what a knockout!

The same can be said for this American Lady, a familiar species in the US also.

Tuesday, January 13, 2009

Three goldencheeks!

Today we redid a flock at the Moxviquil site that we did more than three weeks ago. (“Doing a flock”, for those of you who just tuned in, is shop talk for describing a mixed species flock at selected sites here in Chiapas, Mexico, in hopes of finding the endangered Golden-cheeked Warbler as a flock member.) When we first did this flock I was feeling sick and because of that, basically put in a minimal effort. Birds were going up and down a steep mountainside, and I wasn’t always able to keep up with them, as I tried to follow while panting, coughing and spitting, and nursing a splitting headache. After we were done, I went straight to bed and missed out on a Pronatura raffle, in which field assistant Hector incidentally won a microwave. We didn’t find any goldencheeks that time, but last week our colleagues from Pronatura Chiapas showed us two goldencheeks in that flock.

So we had to go back and try again.

Yesterday we finished our work at the Granada site, and tomorrow we will travel to Coapilla, our last field site here. The weather forecast for today was rain, but I thought “hey – if we’re lucky and the rain holds off until 11 AM, we can redo that flock”.

Well, I guess we were lucky, because it didn’t rain, and we found not two but three goldencheeks in that flock!

We started a little before 7 AM. Within the first 20 minutes of observation, I found an immature female type goldencheek – a bird with a largely white throat. Five minutes later, another goldencheek. This one with a black throat, but a white chin - possibly an adult female or immature male. Then six minutes after that, an adult male goldencheek (throat and chin all black).

Here’s that ‘white-throated’ goldencheek.

Incidentally, this flock also had two Black-throated Green Warblers, and adult male and a lightly marked immature type bird. Around these parts, BT green is not a common species. These two individuals I had seen before though, on an afternoon walk around the house. I had mentioned them to our Pronatura colleagues, who had nodded while squinting their eyes ever so slightly, as if thinking "sure John, if you say so". Perhaps they thought I was misidentifying goldencheeks for BT greens. One of the Pronatura people in passing had seen two goldencheeks but no BT greens in that flock, and here was that foreigner claiming there were two BT greens but no goldencheeks there. Something clearly did not compute.

But, as we found today, I hadn't hallucinated my earlier Black-throated Green Warblers, and they hadn't fabricated their earlier Golden-cheeked Warblers either. Odd though that I never saw these goldencheeks that all this time were so near the house!

While sorting through the flock, we also found a Blue-throated Motmot (pictured at top) just quietly sitting there in a tree. Not a flock member, but an onlooker.

The same motmot from a different angle.

As I said, we will be traveling to another part of the state tomorrow, and stay at a hotel there. At this point, I don’t know what the internet access situation is like there, so I can’t say how often I will be able to post.

Monday, January 12, 2009

Undertail coverts

In the excellent Field Guide to Warblers of North America (1997), Jon Dunn and Kimball Garrett note when describing the spring adult male goldencheek that “a few show short black streaks on the undertail coverts” (1).

Today at the Granada field site, we had such a bird.

It was an adult male, and I’m guessing this particular plumage detail only applies to adult males.

This is a detail from Plate 31 of that same field guide. Here, Golden-cheeked is depicted with fairly small streaks on the undertail coverts, especially when compared to Black-and-white Warbler or even Townsend’s Warbler.

This is the underside of another Golden-cheeked Warbler, also an adult male. It’s the bird we saw last Thursday in La Granada. This particular individual only has one much smaller streak on the undertail coverts.

A beautiful bird – but a bit of a skulker – is Blue-hooded (or Elegant) Euphonia. This adult male and a female were perched in a shrub, where they assumed they had sufficient cover, for they let me approach quite close and never flew out of there.

(1) Jon Dunn & Kimball Garrett (1997) A Field Guide to Warblers of North America, Peterson Field Guide Series, Houghton Mifflin, Boston.

Sunday, January 11, 2009

Another goldencheek

Today’s flock was hard work, but rewarding, because it had another goldencheek. This was our fourth location at the Granada site, and as invariably happens at any site, each day it becomes harder to find flocks you haven’t already done. Walking through the forest with GPS in hand, the question is always “how far are we from yesterday’s flock?” Or, when you’ve done three flocks already, the question becomes “where the heck can we go that’s far enough away from these earlier flocks?”

Thus we roamed the land, in search of birds that we hadn’t already seen.

By nine ‘o clock, we still had not found a flock, although we finally did get to an area that to me at least looked promising. As I said to Hector, it’s not enough just wanting to see a goldencheek – you gotta expect it. This here is where I would expect to find the species.

But the only thing we found there was dead silence.

Ten minutes later and a couple of hundred meters further, though – bang! Suddenly birds everywhere.

A flock that in the end wasn’t huge, merely large, but with birds roving around in a fairly tight pack. It had not one but two Greater Pewees.

It also had 6 Yellow-backed Orioles, whose song I just love. A couple of Yellow-backed Oriole (Icterus chrysater) songs can be heard here: http://www.serraniagua.org/index.php?option=com_zoom&Itemid=39&catid=6&PageNo=5

The Golden-cheeked Warbler in this flock was not an adult male, like the majority of goldencheeks here, but what I will tentatively call an immature female type. It had no black at all on the throat, and very little black on the breast and light streaking on the sides. The upperparts were olive. Although we saw it repeatedly, we never got close enough for a decent photo.

So, in an effort to outdo myself at ‘crappiest Golden-cheeked Warbler photo ever’ – here’s a photo of the bird!

I assure you, the bird is in there! Click on the photo, and see if you can find it. Of course the lighting wasn’t great and my camera will only take reasonable bird photos of birds that just happen to be really close. When this photo was taken, the bird was probably 50 m away, good enough for bins but way too far for my camera obviously.

Here’s an enlargement of that photo. The bird is barely recognizable.

Soon after I found this bird, I thought I saw another: an adult male. But I didn’t see it well enough to safely call it, so after a while I said to Hector “Well, I think we have one and a half goldencheek”, to which he wittily replied “let’s try and find the other half then”.

But we never did.

Saturday, January 10, 2009

Wait a minute...

The protocol of our Golden-cheeked Warbler study prescribes that when we go out to look for a warbler flock in hopes of finding a goldencheek in there, we keep at least 500 m distance from flocks already described. Of course this is to minimize the chance of describing the same flock twice.

Today, our third day at the Granada field site, we walked past our first location, which two days ago had a goldencheek.

About 500 m past that site, we encountered birds. Within 45 minutes, we had identified 20 flock members, including an adult male Golden-cheeked Warbler. Also in this group was a pair of White-winged Tanagers (male pictured above).

Wait a minute… Golden-cheeked Warbler? Wilson’s Warbler? Greater Pewee? Painted Redstart? Townsend’s Warbler? Hermit Warbler? Red-faced Warbler? Blue-gray Gnatcatcher? Blue-headed Vireo? A pair of White-winged Tanagers?

All these birds were also in the flock two days ago, 500 m away!

Most of these birds of course are found in just about any flock, but the White-winged Tanagers gave me the creeps. The only previous flock that had them – also a pair – was that flock 500 m away two days ago. And that flock also had an adult male goldencheek!

Around nine, I was seriously wondering if this wasn’t the same flock. It seemed to have fewer Townsend’s Warblers and more Wilson’s Warblers, and it had a few birds not seen in the flock two days ago (like Bullock’s Oriole). At this point in the survey, however, the flock composition appeared to be suspiciously similar.

It happened once at our Moxviquil site, when we were actually quite a bit closer to a previous flock location. We stopped observations then.

Today I decided to continue, and later I was glad I did. As we continued observing the flock, more and more differences were found. This flock had two Blue-gray Gnatcatchers, for example – not a species that is easily overlooked – while the other flock just had one. This flock had two Painted Redstarts and a Slate-throated Redstart; the other flock had just one Painted Redstart. This flock only had one Olive Warbler: it called frequently, but its calls went unanswered. It had just one Hutton’s Vireo, while the other had two. It had a Warbling Vireo, not found in the other flock. There were other differences.

I also figured that if it was the same flock, they would sooner or later gravitate toward the same area – but they never did.

When after four hours of observation we were done with this flock, I decided to simply walk to the other flock area, and see if we would find the previous flock there.

And lo and behold! – there they all were! That is to say, we didn’t find the entire flock complete in just 10 minutes of surveying – it usually takes hours – but we found the Blue-gray Gnatcatcher, the Painted Redstart, one of the Crescent-chested Warblers, an Olive Warbler and a Townsend’s Warbler. In pretty much the same spot they were two days ago!

Relieved and content that we found another goldencheek – of which I didn’t get any photos, alas – we returned to Teopisca for lunch. The last three days we have been frequenting this taquería called El Buen Amigo, where we like the tacos. The price is also right, at just four pesos per taco.

The owner saw us coming, and called out to me “primo!” This means cousin in Spanish – more than good friends, we are family now!

Friday, January 9, 2009

Black-throated Green Warbler

The bird pictured above is a Black-throated Green Warbler. We found two individuals in the flock this morning; this adult male and a female-type bird. They are about as rare as Golden-cheeked Warblers here in Chiapas; further south, they become much more common. They seem to have a preference for a well-developed mid-story, and indeed the area occupied by today’s flock had exactly that. The bird in the picture is foraging in so-called encino oak, a favorite actually of Golden-cheeked Warblers. The area used by today's flock had very little of it - maybe that's why we didn't find any goldencheeks in this flock.

On the way back, we came across these two young bulls, head-locked in a fight.

Thursday, January 8, 2009

Granada

Today some photos of a an adult male Golden-cheeked Warbler that we found in Granada, our fourth field site here in Chiapas. This site is about 20 miles east of San Cristóbal de las Casas, which has been our base for the last three weeks. We thought about relocating to Teopisca, to be closer to the Granada site. Then we found that it wasn’t really as far as originally thought. We also found that the hotel there wasn’t as nice as originally hoped for. All in all we considered we were better off staying at Pronatura’s field station in Moxviquil, so after one night in Teopisca, we returned to San Cristóbal today.

I don’t have a big expensive camera with a big expensive lens, so these photos are about as good as it gets for me. Click on the photos for larger views.

This bird was part of a fairly small flock, which comprised 25 members of 16 different species. The Granada site is at a slightly lower elevation than the previous three sites closer to San Cristóbal, and the bird community there, likewise, is slightly different, including Blue-gray Gnatcatchers for example, White-winged Tanagers and Blue-crowned Euphonias. We also saw a Tropical Mockingbird. Those are birds we didn’t encounter around San Cristóbal, which is about 500 m higher in elevation than Granada. Around San Cristóbal, Slate-throated Redstart is common, and Painted Redstart is not. Here, we found a Painted Redstart today and didn’t see any Slate-throateds. Another ‘new’ bird here was Grace’s Warbler, often a common species in Central American pine-oak forest, but curiously absent from our previous field sites.

Now that we’re back in Moxviquil (San Cristóbal), we will be commuting to the Granada field site for the next four or five days. The colectivo from San Cristóbal goes right past the entrance to the field site, and the whole trip is maybe 40 minutes. Incidentally, this road is the Panamericana, or Pan-American Highway, which runs all the way from Alaska to Tierro del Fuego (but with a 54 mile rain forest gap in Panama called the Darién Gap). I have now traveled this road in Canada, Mexico, El Salvador, Honduras, Nicaragua and Costa Rica. A large part of its charm is found in its local particularity: many parts of it, including this stretch in Chiapas, are two-lane rural roads (one lane each way) that connect small villages, and much of its traffic is local.

Back in San Cristóbal, our taxi driver had a little TV screen installed on the passenger side, and was busy watching some movie. Every second, while driving, he would briefly glance at the road ahead of him, and then return to his movie. When after a while I mentioned to Hector that the guy was taking a very circuitous route, and that he was probably too busy watching TV, he immediately paused his program. Two minutes later, we were back in Moxviquil, safe and sound.

In this photo, the goldencheek appears to have some light fringes on the dark throat, but that’s absent in the other photos and wasn’t apparent in the field. It is probably an artifact caused by the bird stretching its throat somewhat. A pure black throat, black eye line and blackish upperparts are field marks of an adult male Golden-cheeked Warbler.

Wednesday, January 7, 2009

A humbling experience

Readers of this blog will remember my earlier grumblings about the Moxviquil and Huitepec sites, where we barely encountered Golden-cheeked Warblers. I even went so far as to say these sites may have been chosen by Pronatura more because they are Pronatura sites than because they are good Golden-cheeked Warbler sites.

Clearly, I was wrong. I have to take that back.

But first, a little prehistory.

The previous two winters, I worked on this Golden-cheeked Warbler project in Honduras, as part of an effort to describe the wintering ecology of this species, and at the same time monitor the species across the wintering range. That range comprises the mesoamerican pine-oak ecoregion, from the highlands of Chiapas, Mexico all the way down to northwestern Nicaragua. Countries in-between where the species is found in winter are Guatemala, El Salvador and Honduras.

The Honduran results, in particular the distribution of various age/sex classes, were similar to those found in surrounding countries. The results from Chiapas, however, in previous years contrasted markedly with those found in other places. In Chiapas, the percentage of adult males encountered was much larger than that found elsewhere in the ecoregion, a difference which is known from the literature but for which more data is needed.

In order to firmly establish this tendency by minimizing observer bias, the idea came up to switch observer teams between Honduras and Chiapas this year.

That’s the reason why I am in Chiapas now, and why Alberto Martinez did some Honduran sites this season. Incidentally, this is the same Alberto who accompanied me on the trip to Costa Rica late November / early December, to look for Golden-cheeked Warblers there. He’s an excellent observer.

So when he told me a couple of days ago that Moxviquil is in fact the best Golden-cheeked Warbler site in the area, I was just dumbfounded. I know Alberto well enough to tell that he wasn’t bullsh***ing me. But how is it possible then that we found only one goldencheek there, when apparently last year they found 10 individuals here?

So this morning, a Pronatura delegation consisting of Alberto, Efrain, Javier and Jorge joined Hector and myself in the field at Moxviquil, to show us where to find Golden-cheeked Warblers. At times it felt a little as if we were being audited, and to me it seemed there was perhaps some machismo involved as well, although exactly how much of that was real or perceived I couldn’t tell.

And sure enough, within maybe half an hour, Alberto had found two goldencheeks. There I was, having these birds spoonfed to me; a humbling, almost humiliating experience.

I saw both birds well; one was an adult male, the other was an adult female / immature male type, with some white on the throat. This last bird I got a crappy picture of (above).

These birds were in a flock close to the field station, presumably the same flock we did on one of our first days here, when I was still sick and went right back to bed afterwards. I do remember thinking it was a rather minimal effort that day. Birds moved fast up the steep slope and I was barely able to follow then, constantly panting, coughing and spitting, and with a pounding headache.

An hour and a half later Alberto found a third bird. This bird he lost almost immediately after he found it, and for a while nobody else saw it, until about 20 minutes later Javier called it out. Yup, it was a goldencheek alright. This bird also had white fringes on the central throat feathers, but a black chin, and dark olive upperparts. It was called an immature male but I think it may just as well have been an adult female.

This bird was found exactly 200 m on each side away from other flocks we had described a couple of weeks ago! We saw a Crescent-chested Warbler and a Wilson’s Warbler nearby, and we heard a Greater Pewee in that area, but otherwise this hardly appeared to be a flock.

So clearly these birds are here. Why then did we see only one, during 5 mornings of field work here?

I think there may be a couple of explanations. First, Alberto and the others know these sites much better than we do. Instead of walking around looking for warblers, they went right to the spots where in previous years they had found goldencheeks. Second, this was a very strong team. For some reason, my teams have always been ‘weak’ teams, with only one skilled observer who doubles observing and note-taking duties, while also teaching the other observer how to identify birds in these mixed species flocks. And even today’s strong team failed to find goldencheeks in some flocks at spots where in previous years they were found.

The flock with the two goldencheeks we will do again, when we return next week.