Wednesday, December 31, 2008

A big flock

Today, the last day of the year, we started on a new site: Laguna del Cochi. The idea here is to visit five different sites, and to describe five different flocks for each site – math wizards among you will have understood that we plan to describe 25 flocks then. Today was flock number 11.

I hate to say it, but the previous two sites, Moxviquil and Huitepec, to me didn’t seem like prime wintering habitat for the Golden-cheeked Warbler. Sure, we registered the species at both sites, but only barely. I couldn't help but feel that these sites were chosen by Pronatura more because they happen to be Pronatura reserves than for being representative wintering habitat for Golden-cheeked Warblers.

Today’s site – not a Pronatura reserve – was different. This was classic pine-oak, and it didn’t take us long to find warblers. I was hopeful right from the start, telling Hector “Wow – this is what they [i.e. Golden-cheeked Warblers] like: pines in the tree layer, oaks in the middle layer, half-open situations here and there… perfect! This is where you expect to encounter the species.”

I grew even more hopeful when the flock we found turned out to be huge – in fact the biggest flock I’ve ever described in three years of my participation in this study in Central America.

The most abundant warbler species in this flock was Hermit Warbler; I counted at least 18 individuals, and feel that this is still on the conservative side. Yesterday I mentioned a study from 1994 in which Hermit Warbler was found to be intermediate in abundance between the locally abundant Townsend’s Warbler and the locally rare Golden-cheeked and Black-throated Green Warblers. Well, Townsend’s Warblers seem to be abundant almost anywhere we go here. But Hermit Warbler, a conifer specialist, is quite rare in oak forests, and I was not surprised to find it in greater numbers at today’s pine-oak site. I remember one flock in Honduras that had a similar number of Hermit Warblers in it.

There was a mini-flock of 15 Bushtits in this flock, and again they went wherever the larger flock went, so to me they seemed totally legit as flock members.

The same cannot be said for a noisy group of 12 Gray-silky Flycatchers (left), which did associate briefly with our mixed flock, but ultimately seemed to be doing their own thing. I didn’t consider this Red Crossbill (right) a flock member either.

After four hours of studying the flock, having identified 76 individuals belonging to 24 different species as flock members, we still had not found a Golden-cheeked Warbler among them. I just couldn’t believe that, kept saying to Hector “there’s gotta be one in there!

Then, finally, there it was. Again, an adult male Golden-cheeked Warbler. We both had good looks at the bird, and were able to determine it was unbanded.

We also found this caterpillar. I don't think it has anything to fear from a warbler flock, no matter how big.

Tuesday, December 30, 2008

Bingo!

This awesome bird is a Blue-throated Motmot. It occurs here in montane forests, but is nowhere common in its fairly small Central American range. Ever since I’d seen its name on the checklist for Huitepec, it had been pretty high on my wish list. Motmots are fantastic, charismatic birds, and I was thrilled when I spotted this bird sitting at mid-level in the understory of mature oak forest in Huitepec.

After Pink-headed Warbler, Hooded Grosbeak, Garnet-throated Hummingbird, Green-throated Mountain Gem and Black-capped Swallow, this Blue-throated Motmot was the sixth ‘lifer’ for me here in Chiapas.

This was our fifth and final day at the Huitepec site, and it was now or never for Golden-cheeked Warbler.

We found one! Again it was a male, and although I saw this bird for only half a second, I saw it well enough to call it. Unfortunately, I only saw the head and upper parts of the bird, never the feet, so I can’t say if it was banded or not.

It was part of the biggest flock we’ve encountered at this site, in which I was able to identify 39 individuals of 17 different species. Interestingly, the bird we found last week in Moxviquil was also part of the biggest flock we encountered at that site.

Today’s flock was heavy on Crescent-chested Warblers, of which I counted at least 9 individuals. When there’s 20-30 birds flitting through the treetops, it’s hard to identify all of them at the same time, and to know which ones you already identified earlier. But, as I said to my field assistant Hector, seeing a mixed warbler flock move through the trees overhead really is birding heaven. For me, it doesn’t get any better than this. Much as I love raptors, there is nothing like the sight of these small creatures darting through the leaves in search of insects. Sure, it’s hard work, keeping up with the flow of the group and identifying birds that are often half-hid among leaves or behind branches, but incredibly satisfying too. I love doing this work.

The flock had at least 6 Townsend’s Warblers. According to Dunn & Garrett’s Warbler Guide, “in Chiapas, Golden-cheeks are estimated to be only about 1 percent as numerous as Townsend’s Warblers” (1). This sentence intrigued me mightily, and I did some research online to find out where Dunn & Garrett get this number from. Turns out this figure is presented in Vidal, Macías-Caballero & Duncan (1994), an article published in The Condor, titled "The occurrence and ecology of the Golden-cheeked Warbler in the highlands of Northern Chiapas, Mexico" (2). For anyone interested in the article, it can be downloaded freely here: http://elibrary.unm.edu/sora/Condor/files/issues/v096n03/p0684-p0691.pdf

It’s an interesting article. Their methodology then was quite different from ours now, so there is really no point in comparing their results to ours. Of course we’re only two weeks into the field work here. I’ve been thinking a lot these past days about why we’re not seeing more goldencheeks, and to me it seems a matter of habitat. I think this species is more abundant in pine-oak forests, and less abundant in young (Moxviquil) or older (Huitepec) oak forests. Upcoming sites I believe have more pines, so I expect to be seeing more goldencheeks in the coming three weeks.

Another incredibly charismatic bird in the mixed species flocks is the well-known Black-and-white Warbler. This is an immature male, acrobatically hanging upside down, reaching for insects and small invertebrates that other warblers can't reach.


(1)
Jon L. Dunn & Kimball Garrett (1997) A field guide to warblers of North America; Peterson Field Guide Series, 49. Quoted sentence is found on page 294.

(2)
Vidal, Macías-Caballero & Duncan (1994) The occurrence and ecology of the Golden-cheeked Warbler in the highlands of Northern Chiapas, Mexico. Condor 96: 684-691.

Monday, December 29, 2008

A Townsend's Warbler feeding

Today a series of pics showing a female Townsend’s Warbler feeding in an oak, before sunrise.

Townsend’s Warbler is, after Wilson’s Warbler, the most common species in our flocks here. In these parts, Wilson’s Warblers seem to be everywhere, and are opportunistic flock members. They will move with the flock if there happens to be one in the area. But we find plenty of them outside mixed warbler flocks. Townsend’s Warblers, however, are usually not found outside the flocks.

Townsend’s Warbler, a common breeder in Oregon, Washington, British Columbia and southern Alaska, winters in two distinct geographical areas. Coastal populations winter in coastal Washington, Oregon and California, while interior populations winter from northern Mexico south to northern Nicaragua. In the northern part of this interior winter range, it is often the most common species in mixed warbler flocks.

It is certainly more numerous here in Chiapas than it is in Honduras.

Sunday, December 28, 2008

Oops... I did it again!

I saw another Black-throated Blue Warbler today! About a week ago I saw an adult male (pictured above) in Moxviquil, today another adult male in Huitepec, which is maybe 10 km from Moxviquil.

These birds are not supposed to be here!

Again I quote from Cornell University’s Birds of North America:

In winter, mostly in the Greater Antilles, from Puerto Rico, Hispaniola, Cuba to Jamaica; also in the Bahamas. Occasional in the Lesser Antilles, as far south as Trinidad (ffrench 1991) and along the Caribbean coast of the Yucatan, Belize, Honduras. Recorded as rare or casual winter visitor along the Caribbean coasts of Costa Rica, Panama, Colombia, and Venezuela (Ridgely and Gwynne 1989). One record from Ecuador of a male present from February through early June along east slope of Andes near Cosanga, Napo province (Martin et al. 2004). Small numbers winter in s. Florida and a few occasionally farther north (Root 1988). (1)

I think we can add to that: occasional winter visitor in Chiapas, Mexico.

This second bird I didn’t get photos of, but like last week’s bird it was an adult male, not a terribly difficult ID.

Also a couple of Black-throated Green Warblers in today’s flock, but – you’ve guessed it – no Golden-cheeked Warblers.


(1):
Holmes, Richard T., N. L. Rodenhouse and T. S. Sillett. 2005. Black-throated Blue Warbler (Dendroica caerulescens), The Birds of North America Online (A. Poole, Ed.). Ithaca: Cornell Lab of Ornithology; Retrieved from the Birds of North America Online: http://bna.birds.cornell.edu/bna/species/087doi:10.2173/bna.87

Saturday, December 27, 2008

Nashville Warbler

Well! I hate to sound like a broken record, but today again we did not find any Golden-cheeked Warblers in Huitepec, but again saw a warbler that I have never seen before in pine-oak forest. (It doesn’t winter as far south as Honduras, that’s why.) This time the warbler was a Nashville, which, according to Dunn & Garrett (1997), on the wintering grounds is found in humid forests, shrubby areas, forest edges, coffee plantations, parks, and gardens (1). Neither Dunn & Garrett nor Cornell’s BNA account (2) mention a specific elevational range, but ‘coffee plantations’ (Dunn & Garrett) and ‘cloud forest’ (BNA account) suggest that this bird can be found at higher elevations.

The BNA account gives more detail:

In central and s. Mexico from Coahuila and Nayarit south through Oaxaca and Chiapas, seen primarily in low deciduous open forests and suburban gardens (A. M. Sada pers. comm.). In Veracruz, 1 bird netted at 700 m and a second observed in undisturbed rain and cloud forests of the Santa Marta crater (Rappole et al. 1992).

In w. Mexico, from s. Sinaloa to s. Oaxaca, found over wide range of habitats. Of 179 birds observed, 45% in cloud forest, 30% in tropical deciduous forest, 17% in disturbed deciduous forest (second growth), 5% in thorn forest, and 3% in pine-oak-fir forest (Hutto 1992). Not found in oak woodland (Hutto 1980).

That last line to me is intriguing, since more than 90% of all trees in the area around San Cristóbal, including Huitepec, are oaks. Huitepec is older, humid forest, with big, epiphyte-laden trees. But those trees are all oaks.

We found the bird at the entrance to the reserve, in what I would describe as disturbed, second growth habitat. Surrounded by oaks.


(1) Dunn & Garrett (1997) A field guide to the warblers of North America; Peterson Field Guide Series.

(2) Williams, Janet Mci. 1996. Nashville Warbler (Vermivora ruficapilla), The Birds of North America Online (A. Poole, Ed.). Ithaca: Cornell Lab of Ornithology; Retrieved from the Birds of North America Online: http://bna.birds.cornell.edu/bna/species/205doi:10.2173/bna.205

Friday, December 26, 2008

Another lowland warbler!

Yesterday I wrote about the Magnolia Warbler that I never expected to see in Huitepec Reserve, because the elevation here is just too high. Well, today I saw another bird with a similar elevational distribution: Worm-eating Warbler. (And yes, that bird pictured above is a Crescent-chested Warbler, fairly common here.)

Cornell’s BNA account for Worm-eating Warbler gives a winter range between sea level and 1,500 m on both Atlantic and Pacific slopes of Central America. But again, Huitepec is at more than 2,300 masl!

Clearly, there must be something here that’s attractive to these lowland and foothills species. Perhaps these birds made migration stopovers here and, well, decided they liked it!

We didn’t get to study a flock today. Walking though the forest, we encountered small pockets of insectivorous birds everywhere, but somehow I never got the impression of a flock. Maybe the forest here is too dense for flocks to be readily apparent, maybe every one of those little pockets in reality was a flock. It didn’t bother me too much. For me, today’s field work was all about reconnaissance. Just for fun, I ticked off all the Wilson’s Warblers I saw or heard between 7:15 AM and 1 PM. Got to 21 Wilson’s Warblers. Other common warblers in this forest include Golden-browed and Rufous-capped, Crescent-chested, and Townsend’s Warblers. MacGillivray’s Warblers also appear to be fairly numerous here.

But Golden-cheeked Warblers… not so much.

Thursday, December 25, 2008

Weirdo warblers

After more than a week on the Golden-cheeked Warbler project here in Chiapas, and the goldencheek counter still only at one, it’s clear that we’re off to a poor start. I expected to have seen more of them by now. I thought I briefly saw one yesterday, but I got such lousy looks and the bird never reappeared, that I decided not to count it.

What I didn’t expect to see here was a Magnolia Warbler. For some reason, we’re not seeing many Golden-cheeked Warblers but we’re seeing these goofball warbler species that aren’t supposed to be here. Last week we had a male Black-throated Blue Warbler in one of the flocks. Yesterday, we found a Magnolia Warbler in the first flock we studied at our second site, Huitepec, in the mountains just outside of San Cristóbal.

Mind you, we’re not really out of wintering range for Magnolia Warbler here. But I have never seen one in warbler flocks in mesoamerican pine-oak forests, because those flocks are generally at elevations too high for Magnolia Warbler.

This species, according Cornell’s Birds of North America (1) , occurs on the wintering grounds in a variety of habitats between sea level and 1,500 masl. The bird we saw in Huitepec was in cloud forest, at an elevation of 2,351 masl!

Another thing that occurred to me while observing this flock: do certain flock members perhaps stick together? For example, the first birds we encountered in this flock were a female Black-and-white Warbler and a Slate-throated Redstart. Both are birds with very distinctive foraging styles; quite different, both however utilizing the same middle layer of the forest. During the two and a half hours that we observed this flock, these two would occasionally pop up, always together. Other duos we observed in this flock were the Magnolia Warbler paired with one of the three Blue-headed Vireos, and two female/immature type Townsend's Warblers. Seeing one member of these duos was usually followed by seeing the other.

This is not something I've observed or been aware of before, but – if true – could be an interesting aspect of flock dynamics. Such a phenomenon may be more pronounced in forests with dense vegetation, like for example this cloud forest at Huitepec, where visibility is limited, as compared to more open situations in classic pine-oak forest. What I have noticed before is that the area used by the flock tends to be smaller in forests with dense vegetation, and bigger in more open forest.

(1): Hall, George A. 1994. Magnolia Warbler (Dendroica magnolia), The Birds of North America Online (A. Poole, Ed.). Ithaca: Cornell Lab of Ornithology; Retrieved from the Birds of North America Online: http://bna.birds.cornell.edu/bna/species/136doi:10.2173/bna.136

Wednesday, December 24, 2008

Merry Christmas

Merry Christmas, dear reader, also on behalf of… the zapatista freedom fighters in the Mexican State of Chiapas! You probably noticed – the nativity scene pictured above is not your typical, garden-variety nativity scene. Why, Baby Jesus is wearing a balaclava, as do the shepherds, who are all armed with guns! What in Baby Jesus’ name is going on here?

Well, this nativity scene is from Tierradentro, an EZLN (zapatista) owned coffee place / restaurant in downtown San Cristóbal de las Casas. It’s a weird place, favored by Europeans and Mexicans alike, where the atmosphere is friendly and relaxed, and the music is usually some new-agey kind of twang. Its customers are, for the most part, alternative scene types with laptops who combine knitwear and vaguely tribal looking accessories with The North Face cargo pants and expensive hiking boots. In a word, anti-globalists.

And that’s where the zapatistas come in: the movement was originally started in 1994 in reaction to NAFTA, the North American Free Trade Agreement, which opened the Mexican market to cheap, mass-produced US corn, effectively pushing an already poor Chiapas into extreme poverty. The EZLN, or Ejército Zapatista de Liberación Nacional, initially pursued a revolution in all of Mexico, but in the end were only able to claim some territories in the southern Mexican state of Chiapas, which they still control. They have taken up the cause of the poor indigenous peoples of Chiapas, such as the Tzotzil and Tzeltal, direct descendants of the Mayan people.

And that’s where those anti-globalists come in. Mostly well-educated Europeans, who feel nostalgic for ancient cultures and who feel hostile toward the corporate cultures they belong to and after their vacation is over will return to.

But how ironic: the zapatista revolution is a revolution almost trademarked. The sheer variety of zapatista trinkets is overwhelming! There’s zapatista action figures, zapatista t-shirts, zapatista calendars, zapatista posters, zapatista books, even zapatista ashtrays, zapatista cigarette lighters, zapatista keychains and zapatista bottle openers.

No surprise then to find a zapatista nativity scene.

Tuesday, December 23, 2008

Golden-cheeked Warbler!

Finally we had one in the flock this morning! This was our last flock at the Moxviquil site, and what a nice big juicy flock it was. It had 45 members from 18 different species, including 5 vireos of 4 different species. Vireos are everywhere in these oak forests; Blue-headed of course, and Warbling, and because this is Mexico also Hutton’s Vireo. But a bird I didn’t expect to see here was Cassin’s Vireo. Intermediate between Blue-headed and Plumbeous – both of which I’d seen in Honduran pine-oak forests – this was a first for me in these warbler flocks. But I saw it repeatedly, and every time it appeared subtly yet distinctly different from the two Blue-headed Vireos that were also part of this flock.** Other attractive flock members included a Red-faced Warbler, a female Rose-throated Becard, and a couple of MacGillivray’s Warblers. Most abundant flock member today was Bushtit – a species whose membership of insectivorous passerine flocks is perhaps debatable. They travel in dense flocks and stick close together, seemingly doing their own thing. Yet for the entire four hours that we observed this flock, we never saw them away from the other flock members. To me it seemed they totally paid their flock dues and deserved membership wholeheartedly. They were 17 strong, and formed a flock within a flock. Their behavior reminded me of Common Bush-Tanagers, who will also occasionally join mixed flocks but always stay close together.

Considering the size of the flock, it was remarkably light on Dendroicas. Besides the adult male goldencheek, there were five Townsend’s Warblers, but no other Dendroicas.

** Postscript: Oliver Komar suggests the Cassin's Vireo may have belonged to the Central American race of Plumbeous Vireo, or that it may have been a young Blue-headed Vireo. I don't have all my field guides here with me, so I cannot delve deeper into this. All I know is that the bird's head was less dark (less 'blue') than a regular Blue-headed Vireo, yet not as pale as a classic Plumbeous Vireo, a bird that is grey overall. This bird had a yellowish-greenish wash on the sides, while the edge between the dark hood and the white throat wasn't as sharply demarcated as in Blue-headed Vireo.

Monday, December 22, 2008

Dutch in Chiapas

Today, Hector and I met with fellow Dutchman Tammo Hoeksema (right), who grows flowers here in Chiapas. He showed us around in his greenhouses, and explained to us all about growing flowers in an eco-friendly way.

We met with Tammo because he has worked with our client Pronatura, and because he lives right next to one of our field sites, Granada.

This field site, by the way, looked great for warbler flocks. Half-open situations with both pines and oaks of various ages made for a diverse, well-structured forest that insectivorous birds just love. Unfortunately, we didn’t get to walk around in it, but I’m sure we will find large flocks at this site. Our current site, Moxviquil, is mostly young oak forest, with some variation in the vegetation only near the entrance. Everybody here tells me that Golden-cheeked Warblers can be found throughout the Moxviquil site, but having birded it for five days now and having seen only one very briefly, I remain sceptical. I asked Javier, one of the Pronatura staff who has worked on the GCWA project, which species is more common here, Black-throated Green or Golden-cheeked? A loaded question, of course, which I’m sure he recognized, because he paused a little before stating that he believed they were more or less equally rare. Well, at Moxviquil I’ve seen three different Black-throated Greens already, including two together, but so far I’ve had only half-a-second view of what I think was a Golden-cheeked. I never saw the head but I saw a warbler with a white belly and breast, black throat and black streaking on the sides, and a blackish upperside. Probably a goldencheek then. But large tracts of forest at the Moxviquil site are quite homogeneous and young; in my experience, older, more differentiated forests tend to be richer in bird life and more attractive to warblers.

Anyway. Tammo was super nice and over coffee told us all about growing flowers in Chiapas. He uses no pesticides. Instead, he controls insects that are harmful to his flowers with insects that are only harmful to those other insects. And he’s got two larger mammals – cats – prowling around to take care of smaller mammals – mice. He told us about the economics of the flower business, how the key driver in this trade is still price, more than quality. His flowers are a little more expensive than regular-grown flowers, but they are of higher quality and last much longer. He tries to convince his clients – hotels, large offices etc – that in the long run they spend less on his flowers, but apparently this is a hard case to make. His main crop is a flower that I knew from Holland, but in a much smaller version. He explained to us that he has to grow them big, because in the Mexican market, ‘bigger is better’. That, of course, is a widespread philosophy on this side of the Atlantic.

For some reason, there are many Dutch here. Tammo knows at least four who live in San Cristóbal. A couple of nights ago, we went to a restaurant called El Gato Gordo (The Fat Cat). There were two girls there whom Hector thought were Argentinian, based on their accents, but at three other tables, Dutch was spoken. I’ve never heard so much Dutch outside of Holland!

Sunday, December 21, 2008

Cold!

Several days later at the Moxviquil site, and I’ve only caught a glimpse of a Golden-cheeked Warbler one afternoon. When we revisited that site the next morning, we found Townsend’s Warblers, Wilson’s Warblers, an Oliver Warbler, an Audubon’s Warbler, and a Tennessee Warbler, but no Golden-cheeked Warbler. These birds, together with a couple of Steller’s Jays, a Hairy Woodpecker, an Eastern Wood-Pewee, a Greater Pewee, a Blue-headed Vireo, a Warbling Vireo, a Bell’s Vireo, a Yellowish Flycatcher, a Hammond’s Flycatcher, and a Ruby-crowned Kinglet, were seen foraging around the field pictured above. And yes, that white stuff on the field is frost! I never imagined I would be freezing cold while looking at warblers. But here in Chiapas, at more than 2,000 m elevation, some clear nights are very cold.

Once the sun is out, the frost on the field melts and vaporizes.

In the afternoon, we went into town and I got myself a Mayan hand-knitted woolly hat and matching scarf, which this morning proved very effective.

Here are some mug shots of three of the four members of the so-called virens super-species. They are closely related to the Golden-cheeked Warbler.

Townsend’s Warblers are here in pretty good numbers.

Hermit Warblers are found in pines, which are scarce at the Moxviquil site. Moxviquil is practically all oak woodlands, with some pines here and there. Rare clusters of three or more pines invariably have one or more Hermit Warblers in them.

Black-throated Green Warblers are not common here, although we’ve seen several individuals now.

But still no Golden-cheeked Warblers in our flocks! A Black-throated Blue Warbler, yes - a bird that I'm assuming is much rarer here than goldencheek - but where are the goldencheeks?

Wednesday, December 17, 2008

A Black-throated Blue Warbler

Our GCWA field season in Chiapas officially kicked off today with the first flock of the season, here in the Moxviquil (“mosh-veekeel”) reserve in the hills surrounding San Cristóbal de las Casas. After having seen exactly zero goldencheeks in Costa Rica, I was eager to see one today.

When we left the field station at daybreak, we heard Wilson’s Warblers chipping left and right, and a little further away several Brown-backed Solitaires were singing their wistful dawn song. Other birds we encountered included a Yellow-faced Grassquit, a Yellow-bellied Sapsucker and some Rufous-collared Thrushes. And more Wilson’s Warblers: that bird is found here clearly in high densities.

However, a real warbler flock was somehow hard to find this morning. When we finally encountered one, it seemed more a loose association of insectivorous birds than a real flock to me. It had a Greater Pewee in it, a bird that calls frequently and is sometimes considered a ‘leader’ of such insectivorous flocks. The other birds were remarkably quiet for most of the time, and only the two Townsend’s Warblers and the two Hutton’s Vireos (and of course the six Wilson’s Warblers) called every now and then. Calling softly was a male Black-throated Blue Warbler, a bird whose main wintering area is in the West Indies and northern South America. I had certainly never seen one as a member of a warbler flock in the mesoamerican pine-oak forest, although I remember seeing one fly over the Cardel, Veracruz hawk watch site last September. That bird was headed this way.

We had lunch (antojitos) in the market hall in downtown San Cristóbal, and then we took a colectivo bus back to the field station. These colectivos are really revamped mini-vans that were originally designed to hold maybe eight people, but now fit 20 Mayans and a tall Dutch guy. Just barely, though.

Late afternoon, when the sun was out and the wind had died down a little, the birding was excellent right outside the field station. The courtyard that yesterday had White-eared Hummingbird now also had Green Violet-ear (another hummer) and Cinnamon-bellied Flowerpiercer.

In trees and shrubs surrounding the field station we found several Townsend’s Warblers, a troupe of Bushtits, a Brown-backed Solitaire, a Gray Catbird, a couple of Rose-breasted Grosbeaks, a Rufous-collared Sparrow, and a Rufous-collared Thrush. On one of the trails we saw a beautiful Red-faced Warbler (an oak specialist) and what appeared to be another warbler flock. We decided to revisit that location tomorrow morning.

Tuesday, December 16, 2008

Arrived in San Cristóbal

Hector and I arrived in San Cristóbal yesterday, and were shown three of the five Golden-cheeked Warbler sites here: Moxviquil, Huitepec and Laguna del Coche. These sites looked promising indeed: in the middle and arboreal layers we noticed plenty of oak of various species. Pronatura Chiapas has been monitoring these sites for GCWA for many years, and as we walked around, it became pretty obvious to me that this must be prime wintering habitat for this species.

That said, we didn’t encounter it today.

We weren’t looking for flocks so much as for access points to the sites, so the fact that we didn’t see a Golden-cheeked Warbler today for me was OK. We only spent some time on one flock, which had Hermit Warblers, Townsend’s Warblers, a Blue-headed Vireo, a Crescent-chested Warbler, a Slate-throated Redstart, a Greater Pewee, several Tufted Flycatchers and a bunch of Common Bush-Tanagers. It probably had more flock members, we only looked through this flock for 15-20 minutes.

I was quite excited when I found a Pink-headed Warbler in this flock! On the ride in, our guide Javier of Pronatura Chiapas had asked me what bird I most wanted to see here – besides a goldencheek of course. Well, Pink-headed Warbler! Yes, Javier said, all birders that visit here always want to see that bird. But they’re not easy to find.

Nice then to find it on the very first day. It is in the same genus with Red Warbler, and like that bird it is quite restricted in its range. While Hector and I were admiring the beauty of this Pink-headed Warbler, we heard Javier call out from a little further. When we got to where he was, he proudly pointed us in the direction of another Pink-headed Warbler. I hope I didn’t sound too jaded when I replied that I had just seen one.

The housing at the Pronatura Moxviquil field station is quite nice, with a beautiful little courtyard garden frequented by many hummingbirds, including the White-eared Hummingbird feeding in the last light of day, pictured above. I think I will like it here.

Sunday, December 14, 2008

In Mexico City

Friday evening I flew from San Salvador to Mexico City, where I joined field assistant Hector. We spent the weekend in the city, and will be flying out to Chiapas on Monday, to start the Chiapas part of the Golden-cheeked Warbler field season 2008-2009.

I’d seen Mexico City from the air and from a bus window a few times before, but this was the first time for me to spend some time in the city itself. Its broad, monumental avenues are not unlike those of Paris or London, while its main park, the Bosque de Chapultepec, is very much like Central Park in New York City. Especially on a mild, sunny Sunday.

Probably not the number one birding destination in and around Mexico City, but among the crowds of people we still got to see 20 different bird species, including six warbler species, a Say’s Phoebe, a flock of Bushtits, and a Curve-billed Thrasher. Of the warblers, only Wilson’s and Audubon’s were abundant in the park, with MacGillivray’s, Hermit, Tennessee and Nashville around in lower numbers.

We encountered Ruby-crowned Kinglets throughout the park, apparently a common winter visitor here.

Friday, December 12, 2008

An endemic vertebrate

El Salvador is a small country. With 5.7 million inhabitants, it is the most densely populated country in Central America, and large parts of it are cultivated. Original remaining habitats here are more scattered and smaller-scaled than for example in Costa Rica.

But El Salvador appears to have at least one endemic vertebrate. It’s a fish. Recently described as sufficiently distinct to be its own species, it lives in Lake Coatepeque, and yesterday I joined a team of biologists from SalvaNatura to look for it.

This fish, Amatitlania coatepeque, is part of a family known as ‘convict cychlids’, so named for their stripey appearance, similar to prison uniforms.

We didn’t actually find the fish, but we found a fisherman who described it to us in quite some detail – it sounded very much like he knew our fish. He also told us that they normally don’t fish for it. It is too small, and when caught gets thrown back. Good news for this fish, which lives nowhere else in the world but in this lake.

His wife made lunch for us: fried fish, caught that morning from the lake. It wasn’t our fish. It was a bigger fish, tilapia, an exotic.

Besides the fish, we also looked for a butterfly, Chlosyne lacinia, or Bordered Patch. Tim, one of my companions yesterday, is studying this fairly common species with a large distribution, all the way from Arizona down to Costa Rica. Since it ranges so widely, it is quite flexible in its selection of host plants and is found in a variety of habitats.

I remember it was quite common last June in the Mexican state of Morelos. Yesterday, we found just this one.

Wednesday, December 10, 2008

Butterflies from Costa Rica

Although Alberto and I returned from Costa Rica several days ago, here is one last post on Costa Rica, this time on butterflies. All four species shown here were photographed in the wild, not in the aforementioned butterfly garden. I photographed them at one of our GCWA field sites, near the town of Acosta. And, interestingly, all four species, according to the excellent Butterflies of Costa Rica (Philip J. DeVries), are associated with cloud forest, even though we didn't consider the humid, montane forest in the hills around Acosta to be cloud forest per se.

The species illustrated above is Anetia thirza insignis, which according to DeVries occurs locally from 900 to 2,600 m on both slopes, in association with cloud forest. (DeVries doesn't give common names, only scientific names.)

This is Hypanartia arcaei, which occurs from 1,200 to over 2,000 m on both slopes.

This dartwhite is Catasticta nimbice bryson, a common species on both slopes from 1,000 to 2,500 m.

And finally this gemmed-satyr is Cyllopsis argentella, which is found from 900 to 2,000 m in cloud forest habitats, and is very common throughout the country.

Monday, December 8, 2008

More critters from Costa Rica

Alright, so the previous post was a lot of talk. There was some catching up to do. But I have a ton more photos from Los Jardines de la Catarata La Paz, a place that seems to have been designed with the photographing tourist in mind. I mean, all the ‘wildlife’ here is boxed or caged, or – when it’s free-ranging – attracted with copious amounts of bananas, all for the benefit of the lazy tourist, who wants to see critters up close but doesn’t want to spend an awful lot of time searching for them. Anyone who's ever visited a rain forest or a cloud forest knows that the wildlife in these places, abundant as it may be, is often damn hard to see. Not so here.

Take this well-fed Tennessee Warbler, for instance. Why bother trying to catch small moving insects when you can eat banana all day every day? There’s enough for everyone, and when the banana is finished, a new one magically appears.

This Baltimore Oriole is singing the Banana Boat Song.

This is a Sara Heliconian, one of the many butterflies in the butterfly garden. The Costa Rica Lonely Planet guide casually boasts that this is the largest butterfly garden in the world, but I’ve seen bigger. It’s pretty big, though. They do a nice job of showing all stages in the butterfly life span with actual specimens.

Here’s another heliconian, Heart-spotted Heliconian.

This is a Polydamas Swallowtail, nectaring.

Here’s a male Violet Sabrewing, a large hummingbird that is easy to observe in the butterfly garden.

This raccoon is debating whether he should have another banana.

And finally a completely wild, unfed creature: the sloth! They may have a bad reputation for being lazy, but this guy – unlike most creatures at the gardens – was actively foraging on food he completely found on his own. OK, so what if that food was leaves from trees, which were quite abundantly available. Still, it’s the principle that counts!

... and we're back!

The Costa Rica trip has ended; Alberto and I are back in San Salvador, from where each of us will start our Golden-cheeked Warbler field season proper, Alberto in Honduras, and me in Chiapas.

And no: we didn’t find any goldencheeks in Costa Rica. We suspect that they might winter there only sporadically, and that it is not a significant wintering area. Truth be told, this trip was plagued by much adversity, mostly in the form of bad weather, and in the end we only visited three potential sites. With more planning and better funding, plus an endorsement from the weather gods, we might have done better. But it was not to be.

Thursday afternoon, we left Tortuguero and headed south again, this time to Guapiles, in the foothills of the Caribbean side of the central mountain range. The plan was to meet up again with Paola in Acosta on Friday evening, so that we could revisit the Acosta site Saturday morning under hopefully better weather conditions. That site seemed the one with the highest potential for goldencheeks, and we didn’t want to leave Costa Rica without having surveyed it thoroughly.

Early Friday morning it was overcast but dry, so we decided to bird the area around the La Selva biological station, recommended to us as a great birding spot by Marcelo, one of the Ticos (Costa Ricans) who helped us on this project.

We got some cool birds, including one of those yellowthroats closely related to the Common Yellowthroat: Olive-crowned Yellowthroat. But of course soon it started raining, and we resumed our way to San Jose, where we would meet Paola at the university library.

While driving, we chanced upon a super-touristy but actually very nice spot called Los Jardines de la Catarata La Paz, or in English the Gardens of the La Paz Waterfalls. It had spectacular waterfalls, a hummingbird garden, an aviary, and cool displays with snakes and frogs. At this point, however, our financial means were severely depleted. Although we joked that this place definitely merited to be checked out for goldencheeks, we obviously couldn’t go here on the project’s budget, and had to shell out the very steep entrance fee ourselves.

But this is where it got interesting. In the eyes of one of the staff, we resembled a wealthy American birding tourist (me) and a local bird guide (Alberto). A blatant case of racial profiling. He then informed us that the entrance fee of USD 32 is waived for the guides.

Instead of telling him we were poor biologists trying to find a bird that isn’t even there, we decided to play along with this scenario, and immediately had great fun performing our respective roles.

I told Alberto that he needed to get me at least 25 lifers from this place, and that I didn’t want any sly tactics from him leading the wealthy gringo birder to yet another souvenir shop – although I did want a very specific T-shirt with all endemic Costa Rican hummingbirds on it. In a word, I was being a difficult client. Alberto played his role and pointed out ‘endemic’ vultures to me, which you could tell from the regular ones “because the endemic vultures don’t flap”. Nice touch, Alberto!

Occasionally, I had to tell Alberto to stop chatting up cute staff members and spend more time getting me birds, but overall the experience here was enjoyable. An ample supply of feeding stations made viewing (and photographing) certain species really easy, like the Emerald Toucanet pictured above.

Here’s another photo of that magnificent bird.

One of the better hummingbirds at the hummingbird garden was this Green Thorntail.

Silver-throated Tanagers are very easy to observe at this place, where feeding stations with peeled bananas keep them busy. We even found a few Tennessee Warblers feeding on banana!

Blue-gray Tanagers are common birds in much of Mexico and Central America, but the feeding stations in combination with a scenic background made for excellent photo ops.

More or less the same thing can be said about Keel-billed Toucan, although the Costa Rican tourist industry would have you believe that this bird is unique to Costa Rica. This photo was made in the aviary. They also had a Chestnut-mandibled Toucan in there, which was so habituated to humans that it would allow people to stroke it.

Worth mentioning are also the free samples of excellent coffee and delectable chocolates available at the gift store. As true freeloaders, we had to sample each and every one of them, and then had to go back to compare some especially good ones… Some of them were ridiculously good.

Speaking of freeloaders... These guys were abundant near the second gift store, and their job is to look cute whenever a tourist points a camera at them. In return, they get free, pre-peeled bananas.

Late afternoon, probably a little later than we should have, we left for San Jose, to pick up Paola from the university library and drive to Acosta.

Saturday morning, it was – lo and behold! – not raining, actually it was quite sunny. And windy. In fact, it was so windy that normally, when looking for warbler flocks in the Golden-cheeked Warbler study, we would not go out in such weather. High winds make it almost as difficult to find insectivorous warblers as pouring rain. But we bravely soldiered on, and found small pockets of birds here and there. We found Slate-throated Redstarts, Black-and-white Warblers, Tennessee Warblers, Chestnut-sided Warblers, and quite a few Black-throated Green Warblers – heck, even a Worm-eating Warbler – but no goldencheeks.

We declared the Costa Rican field season over. We were almost completely out of money, and needed to go back to San Jose to the only bank that would change Mexican pesos into Costa Rican colones. (Mexican pesos…? Long story, don’t ask.)

Well, this bank was of course closed on Saturday, even though several others were open.

Suddenly, we found ourselves having to scrounge dramatically, if we were to make it back to San Salvador. We ate cereal for breakfast, cereal for lunch, and had cereal dinners. Kinda stupid I guess, as a European I always underestimate how difficult it is to change money in Central America. I really should know better by now.

So off we went on our journey across borders, back to San Salvador. We now felt much better prepared for the hassle of crossing the borders, but of course wondered what else they would have in store for us this time.

At the Nicaraguan border, we were not surprised when they told us they wanted to inspect the car again. Sure, go right ahead. Inspection this time was minimal, no doubt because it was already quite late and folks wanted to go home. Oh, but wait… the border is about to close! So we had to hurry up, decided to forfeit the ‘assistance’ of local boys, and thought we had everything in order, when the customs official dryly pointed out that a stamp was missing from my slip of paper. “Ah, but the guy signed it!” “Yes, I see his paragraph, but I also need his stamp. You don’t have that stamp. Please come back with it tomorrow morning, this border is now closed.”

So we thought we almost made it, but a missing stamp made us spend another night in the vehicle.

The next day, said stamp was obtained and we were free to enter Nicaragua.

We drove for maybe 7 hours, from one Nicaraguan border to the next. There, at the border with Honduras, we were assisted by two nice ladies and actually spent less than an hour on all the paperwork. It did cost us a few dollars, and we were running severely short on cash, needing to save some for gas.

Not 200 m into Honduras, we were stopped by the police.

Police road blocks are a common thing in Honduras. The police generally want to see the car’s papers and a driver’s license. Sometimes they ask to see the fire extinguisher and an emergency triangle.

Our police officer was a young guy, who indeed wanted to see these items. We showed them to him, but then he coolly remarked: “You have only one emergency triangle. You need to have two, one for each side. I’m going to give you a ticket.”

I told him I had worked in Honduras before and have had to show the emergency triangle many times, but this was the first time I heard about needing to have two. He was not impressed.

We pleaded with him, telling him we had no money, which at first I think he thought was just our spiel. But we really did have no money, just some Mexican pesos that no-one seemed to want to change for me. Of course, he had no idea what the Mexican peso is worth, and when I offered him some – in exchange for my driver’s license – he was reluctant to accept. His superior eventually was more lenient and accepted the 200 pesos.

Half an hour later, another police road block. Please pull over and park over there.

This time, no flak over the so-called missing triangle, but for this cop, the fire extinguisher wasn’t quite up to par. The safety pin was there, but apparently some kind of cap that goes over it was missing, and out came the ticket book.

Again, pleading on our side, and eventually we were let go without the ticket.

Half hour later. Another police road block. Please pull over.

Here, the cops wanted to hear about what we were doing, about the Golden-cheeked Warbler project, etc etc. We spent some time explaining and went over the project in quite some detail, even bringing out the pine-oak forest alliance report, which they obviously were rather impressed with.

And another half hour later, not far from the border with El Salvador, a fourth police officer stopped us. He asked us if we had the fire extinguisher and the triangle, and when we said yes, he just said OK, and we continued on our way.

We spent maybe two hours in this country but got stopped four times.

At the Salvadoran border, they saw our Salvadoran license plates and waved us through. They never bothered to check our passports.