Friday, June 26, 2009

In Granada

Wakako and I spent a few days in Granada, trying to get away from the daily grind (ahem) of field work at Laguna de Apoyo.

We visited a 'butterfly reserve', went in a so-called 'eco-tour' of a 'private natural reserve', drank juice from a freshly harvested coconut, enjoyed creature comforts such as fast wireless, excellent pizza, and great coffee, and witnessed the arrest of a boy held at gunpoint. I place the first items in quotation marks, because this is Nicaragua, sometimes called "the poor man's Costa Rica", where they try to imitate Costa Rican tourism success stories, but often end up producing a simulacrum of that experience. I don't mean to bitch about this, but the butterfly reserve was little more than a small net-covered garden where a fraction more butterflies were flying around compared to outside the garden, and the 5 dollar admission seemed pricey. (The 7 dollar admission to the one I visited in San Jose, Costa Rica a few weeks ago on the other hand was worth it.)

The guided eco-tour was recommended to us by the tour company as great for birding, and in fairness, the birding there was pretty good. But we were birding in habitat quite similar to that of Laguna de Apoyo, and were seeing familiar birds everywhere. I felt a bit sorry for our guide David, who worked hard to identify birds he spotted or heard, and then enthusiastically would bring a bird to our attention, only to hear us say "yes, those are cool birds, and it's amazing how common they are here." No matter what bird he came up with, we jaded birders had already seen or heard the species many times before. At one point, he became quite excited because he thought he had spotted "the national bird of Costa Rica". Someone had once told me which bird this is, but I had forgotten. He had forgotten the English and scientific names of this bird, so for a while there was confusion about this "national bird of Costa Rica". Eventually, we worked it out, and the answer came as a bit of an anti-climax: Clay-colored Thrush (or Robin). Think about it: a country with a ton of endemics, with many colorful, exotic birds, chooses one of the drabbest, dullest birds around that is common from south Texas all the way down to northern Colombia. Its songs are pretty, but even vocally, it isn't exactly unsurpassed. It just doesn't make sense.

We did get great looks at a pair of White-necked Puffbirds, saw another Osprey, found a Royal Tern, saw some Northern Jacanas and Purple Gallinules, and many Black-headed Trogons. Also several Bare-throated Tiger-Herons (one pictured at top of post), and lots of Howler Monkeys. We enjoyed this trip, but I didn't see any new birds, and I was clearly a lot more knowledgeable about birds and butterflies than our guide. That's OK. This wasn't one of those specialist tours where the objective is to tick off as many species as possible. I've never been on one of those and I don't see myself doing that anytime soon.

From the ferry port in Granada we observed four Black Terns, although we didn't see any on our 20-minute boat trip to the 'private nature reserve'. I've entered my Black Tern sightings into eBird, where they now show up as the southernmost records for this species in June.

Common Morphos were the most common butterfly in the butterfly garden outside of Granada.

In an orchard around the butterfly garden was this Ferrugineous Pygmy-Owl.

We never did figure out what the kid who was arrested at gunpoint on the beach near the ferry port was arrested for. Less than a minute before his arrest, he was swimming in the water along the pier - where the city sewage runs into the lake - and asked us for some money. He did not strike me as a hardened criminal who could only be captured at gunpoint, or who needed to be hit with a police club while lying on the ground, but obviously the Nicaraguan police has a much better handle on these things than I do.

Monday, June 22, 2009

Black Terns

North American Black Terns winter along the Pacific and Atlantic coasts of Central and northern South America. In spring, they are a common migrant along both coastlines in Central America, and are also seen in smaller numbers at inland sites. Some non-breeders, presumably first cycle birds, will summer in Central and northern South America, primarily along the Pacific coast, and possibly also along the Atlantic coast. During this time, the species is rare inland (Heath, Dunn & Agro 2009).

And indeed, at the biological station in Laguna de Apoyo, Nicaragua, folks were quite surprised when I said that almost every other day, I’d see Black Terns fishing on the Laguna. Usually I’d see just one or two individuals, and then one day there were 7.

The next day I had a bird point count scheduled for a waterside location, and hoped to get them on the point count. I did: I got no less than 17 Black Terns! Jeffrey McCrary, the resident biologist at Laguna de Apoyo, has never seen the species at the Laguna in June.

Then today, after Wakako and I arrived in nearby Granada on Lake Nicaragua, we observed three individuals hanging around the ferry port for Ometepe, on the outskirts of town.

All birds I’ve seen here so far had whitish body feathers, indicating first cycle birds.

With birds showing up in multiple locations, I have to wonder: are these birds really so rare here in summer, or is it just that nobody has ever reported them before?

Wednesday, we have a birding trip scheduled to the northwestern side of a nearby volcano, which will include a boat trip on Lake Nicaragua. We will definitely be on the lookout for Black Terns...

Postscript: oddest thing - I report my sightings of three Black Terns today in Granada in eBird, thinking eBird will probably want to double-check that sighting, but no. But the Osprey that we also saw, that eBird finds remarkable! I don't think summering Ospreys are that unusual around here.

Literature cited:
Heath, Shane R., Erica H. Dunn and David J. Agro. 2009. Black Tern (Chlidonias niger), 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/147

Tuesday, June 16, 2009

Leaf display in motmots

Wakako is here with me for two weeks, and on a walk here at the Laguna de Apoyo a few days ago, she and I observed a Turquoise-browed Motmot performing the so-called Leaf Display. This is a curious behavior that is known from at least four of the ten motmot species (Murphy 2008). Use of inedible props has been described for only four avian groups: bowerbirds, fairy-wrens, birds-of-paradise, and the Central American motmots. In the first three taxa, the use of props plays a role in mate acquisition and is associated with males only, but in the case of motmots, both sexes exhibit this behavior and its use appears to be less specific, possibly associated with intraspecific aggression or with status (Murphy 2008).

This behavior is performed by paired and unpaired birds alike, during and outside the breeding season (Murphy 2008).

I have seen it many times myself. Usually what happens is that I will hear several motmots calling from a spot, then the calling reaches a feverish pitch and as I sneak up on them, I will find several birds sitting in the same tree, often with one individual holding a leaf in its bill. Many times, the leaf holder will remain in its place as other individuals fly off, which appears to confirm the aggression / status interpretation. Evidently, when you're a motmot, one of the worst things that could happen to you is being confronted by another motmot holding a leaf in its bill, showing you who is boss. These are curious birds, indeed.

Here's a picture of a Russet-crowned Motmot with a small green leaf in its bill. According to Murphy (2008), it is more common for motmots to use bigger and older (brown or yellow) leaves. I photographed this bird, a Mexican endemic, last summer when I assisted Troy Murphy with work on Streak-backed Orioles in the Sierra de Huautla, in the Mexican state of Morelos.

If you're interested in the article cited above, go here for a download link.

Cited literature:
Murphy, Troy (2008) "Display of an Inedible Prop as a Signal of Aggression? Adaptive Significance of Leaf-Display by the Turquoise-browed Motmot, Eumomota superciliosa" in Ethology 114: 16-21, Blackwell Verlag, Berlin.

Monday, June 15, 2009

Leaf-cutter ants

I arrived in Laguna de Apoyo, Nicaragua, about a week ago, but internet at the biological station was spotty at best until last night. Right now it is actually reasonably fast, so I'm going to taunt the digital powers that be by attempting to upload a couple of videos of leaf-cutter ants marching along on the forest floor. These little videos, shot yesterday, may not be epic cinema, but in my humble opinion they're already more fascinating than certain Warhol cinematic releases, such as Sleep (1963). Judge for yourself.

video

This video shows leaf-cutter ants that have cut pieces of leaf from a tree carrying those pieces back to their nest. If you're a leaf-cutter ant, that's what you do for a living. Neither the beginning nor the end of the line was in sight, so you can imagine these little guys have a lot of walking to do. But, as the saying goes, many hands make light work. It's all very well organized: one line with ants carrying bits of leaf to the nest, and a parallel line of empty-handed ants going out to the tree to get more.

Cinéma vérité indeed. The possibilities for slapstick are obvious, I guess. At the beginning of this movie, one directionally challenged ant bumps into another ant, and they both get a little disoriented for a short while. But there is no street scene - the other ant simply takes a few paces to the side, and resumes his journey.

video

Note how in this movie ("Leaf-cutter Ants 2: The Sequel"), the ant in the middle has trouble keeping his load up, especially when another ant starts walking over the leaf bit while the first one tries to pick it up!

There is a bird here - Clay-colored Robin - with a variety of songs, including one that sounds exactly like the opening credits tune of old Laurel & Hardy movies. So for me it is really not hard to use my imagination here in the forest and look at animals performing little scenes out of silent era slapstick comedies, while hearing the signature tune to one of them.

Which reminds me - there was a girl at the Whitefish Point hawk watch last month who remarked that the Black-throated Green Warbler "sang the Ozzy Osbourne song". I've been mulling over that intriguing statement for weeks now, trying to figure out just exactly which Ozzy Osbourne song shares its melody with a Black-throated Green Warbler song. She made the remark in reference to the so-called 'unaccented ending' song of the BT Green Warbler: "zee zee zee zo zee". I'm not familiar with Mr Osbourne's entire back catalog, but I do know a few classic Black Sabbath tunes, none of which come to mind when listening to the warbler. It seems likely that the statement was made in reference to the reality show that the singer and his family had on MTV some time ago, and I just don't know which song they used on that. It can't be "Paranoid", can it?

Friday, June 5, 2009

Costa Rican butterflies

Last night I arrived in San Jose, Costa Rica, from where I will continue my travels to Laguna de Apoyo in Nicaragua tomorrow morning.

This morning I went to a little-known butterfly garden close to downtown San Jose, at less than 10 minutes walking distance from the hostel I'm staying at. I don't care much for San Jose, but this was a lovely little oasis in this ugly, dirty city. As expected, for the nearly three hours I was there, I was the only visitor.

The place is called Spirogyra Jardin de Mariposas, and it's tucked away in an unattractive part of town, near a shopping center. Once inside, you soon forget that you are in a city, for a waterfall drowns out all city noise while butterflies flutter through dense but well-maintained vegetation.

I guess the first thing that most travelers who come to Costa Rica for this kind of thing would do is leave San Jose, which is why this place will never be run over by tourists, and why it will probably always stay tranquil and beautiful. There were no other visitors there but there were friendly staff who directed me to a short little trail just outside the actual butterfly garden, where more butterflies and a few birds and exotic-looking squirrels could be seen. Just imagine - a little piece of jungle right in San Jose!

Alright - the butterfly at the top of today's entry is the one most people know: the Common Morpho. There were plenty of those flying around in the garden. I've seen them before many times, but I've always found them difficult to photograph, because they do so much flying. There were other species of morpho in the garden, and the even bigger owl butterflies.

The second one from the top is Blue-and-white Heliconian, followed by a very blue Red Cracker. (The red refers to markings on the underside of the wings.) The orange one finally is another heliconian: Orange Banded Heliconian. That's as straightforward as butterfly names come: the long wingshape points to heliconian, it's orange, and it's banded.

The same cannot be said for Jazzy Leafwing (pictured above). I see the basic leafwing shape on this butterfly with wings closed, but I don't know what marking provides the clue to its 'jazziness'; maybe it's in the way it flies?

Here it sits with wings open.

Here finally is a shot of a couple of rows of chrysalids, with a fresh individual (Common Morpho) that just emerged, sat there pumping its wings full of fluid, which will then harden to allow it to fly.

The Lonely Planet guide mentioned a small hummingbird garden "with five species" here, but that alas was not the case. Near the entrance was a small garden cafe called the hummingbird cafe, and a few old and empty feeders hanging from twigs. "No hummingbirds today, I guess" I said to the guy who had let me into the garden. "No," he confirmed. But the little trail outside the butterfly garden had Blue-crowned Motmots, Clay-colored Thrushes and Blue-gray Tanagers.

Wednesday, June 3, 2009

Female Ruby-throated Hummingbird

This blog has led a dormant, almost moribund existence recently. This is about to change. The last two-and-a-half months I had to write another blog for Whitefish Point Bird Observatory, and frankly that blog stole this blog's thunder.

But my field season at Whitefish is over, I'm in New York at the time of writing, and will be off to Central America once again tomorrow.

So... building a bridge between cold and windy northern Michigan and tropical Nicaragua, here's a post with some flight shots of a female Ruby-throated Hummingbird from Whitefish Point. All these shots emphasize the bird's back. As a non-birding friend recently remarked, the green iridescence on the hummer's back is just as beautiful if not more so than the gaudy color on the male's gorget.

One of the things that come out in these shots is the variation in posture between just hanging still in the air, less than a feet from the feeder just outside the picture, and a sudden position change or movement.

I mentioned on the other blog that Chaffinches had appeared at Whitefish Point. The Chaffinch, a common European finch, is sometimes kept as a cage bird in the US. Possibly someone is releasing these birds into the wild, because at some point as many as eight Chaffinches were present on Whitefish Point recently. Their song, flight call and contact call became a common thing to hear around the Point.

Most American birders were puzzled by these sounds. To my European ears, those Chaffinch songs sounded like the Platonic ideal of Chaffinch-ness, but US birders said it sounded "wren-like". I tried listening to it that way - as some kind of odd wren - but failed utterly. No - that song sounded like the Chaffinch, and nothing else.

Soon, I'll be back in Laguna de Apoyo (Nicaragua), to do a butterfly inventory of that area. Expect posts on tropical butterflies here.