It’s one of the commonest of commonplaces when you’re birding the American tropics: “This place looks like an exotic plant nursery!”
Especially this place, because it is … an exotic plant nursery, a quiet corner of Guatemala City’s Universidad Francisco Marroquín where palms and bamboos and other tropical fancies are being raised in pots for use in campus landscaping.
It’s a spectacularly beautiful site, nestled into a steep canyon just a few minutes by taxi from the city’s international airport. I’d meant to have a quick look this morning while I was waiting for the Popol Vul Museum to open, but that look turned into nearly four hours of slow walking and exciting birding.
I found about 40 species on my walk–and surely would have come up with more if I’d had my ear in better.
It’s a blast to see Lesson motmots, rufous-browed peppershrikes, and boat-billed flycatchers, but my favorite thing about visiting Guatemala this time of year has always been the combination of tropical novelties with so many wintering birds from the north. A motmot perched quietly above a path with a feeding wood thrush, a peppershrike hunting at eye level while a yellow-bellied sapsucker studies the tree trunk, a boat-bill striking righteous fear into a little flock of Townsend warblers and warbling vireos: that’s the Guatemala highlands in winter.
My favorite constellation this morning came late in my walk, when a couple of white-naped brush finchesdrew my attention to the weedy edge of a compost area. I love atlapetes, but there was no way I could ignore the magnolia and MacGillivray warblers and stunning yellow-throated vireo feeding alongside them, now was there?
Eventually it was time for me to do some indoor stuff. The museum was well worth the visit, though it wasn’t always entirely clear which objects were real and which were replicas (I’m guessing that I didn’t luck into the one single day in the history of the world when most of the most famous and most often reproduced pieces of Maya art were on loan here together).
I was especially impressed by this curassow-headed whistling vessel. And I think I’ve found my new VENT leader portrait, too.
Behavior: Usually tame but alert in migration and winter, Savannah Sparrows are considerably shyer on the breeding grounds. In the mid-nineteenth century, Thomas Brewer found them “particularly cautious and mistrustful” in the immediate vicinity of the nest, so elusive that he was unable to collect adult birds from the nest, “and only accomplished [their] identification by means of snares.” Indeed, breeding birds are generally detected only when the male climbs a sturdy grass stalk or perched atop a dried forb to sing; even singing territorial birds are easily flushed back into cover.
Migrants and winter birds are easier to see. Savannah Sparrows appear in almost any open habitat, from farm fields to beaches to suburban lawns, where they feed on the ground in loose, shuffling flocks. When disturbed by a human or other potential predator, they may briefly freeze in place or run a few feet before launching into strong flight. Savannah Sparrows almost always call on flushing, a high, slightly scratchy, and very short tsit, repeated at irregular intervals of a second or more.
The same looseness of association that characterizes feeding flocks on the ground is typical of Savannah Sparrows in flight. Flock members may take off one at a time, and frequently fly in different directions, scattering before alighting. Over longer distances, the flight is flowing and swooping, recalling that of a Horned Lark. Wintering and migrating Savannah Sparrows often land in the open in sparsely leafed trees or bushes or perch on tall grass stems or wires to look back at their pursuer, quite unlike the panicked fluttering and barely controlled landings of such other open-country species as Baird, Grasshopper, and Henslow Sparrows, which immediately seek the shelter of the thickest, darkest clump of grass.
Habitat: Savannah Sparrows nest in areas of denser, taller grass with scattered low shrubs and forbs, including pastureland, marshy grasslands, hay fields, and tundra.
Voice: Males sing perched atop grass stems, bushes, low trees, and fences, or from the ground. There is also an infrequently observed song flight, issued “after force-copulating with neighboring female” or “besting neighboring male in physical territorial dispute.” The precise structure of the territorial song is unique to each individual male, but all can be recognized by the serial combination of high-pitched ticking notes, a broadly modulated, flatulent buzz, and a short, thin concluding trill: tik tik tik brrrzzz bee-eee-eee. At a distance, only the central buzz may be audible; it is “thicker,” lower-pitched, and slower than the more penetrating final trill of a Grasshopper Sparrow.
Even by the standard of grassland passerellids, Savannah Sparrows are persistent singers, heard through the day and occasionally even at night. Such volubility may be connected to the species’ tendency to polygyny. In good habitat, where food is plentiful and the breeding season relatively long, a substantial portion of males may form pair bonds with more than one female and assist in the rearing of more than one brood; when conditions are less favorable, and in northern areas where the breeding season is shorter, monogamy is more likely. Copulation without the accompanying pair bond is also frequent.
Detailed description and measurementsdrawn from standard reference works
This description is based on the widespread and abundant western subspecies nevadensis; similar birds can occur in nearly all populations. Individual plumage variation produces birds that are darker, paler, browner, grayer, and more sparsely or more densely streaked than other individuals in the same population.
Adult: Tail feathers short and strongly tapered at tips, gray-brown with the outer vanes edged whitish-gray in fresh plumage. Upper tail coverts and rump tan-brown with black shaft streaks taking up approximately one third of the feather’s width. Ground color of the back brown-gray; conspicuous streaking above dark brown to black, the back feathers edged with dull whitish, creating regular pattern of black streaks and parallel “white” tracks down mantle. Primaries plain gray-brown, secondaries brighter, deeper chestnut in most individuals. Tertials black with dull chestnut edges. Greater coverts deep chestnut like secondaries, with large black teardrops and pale buffy edges creating inconspicuous lower wingbar. Median coverts brown at base, with large black teardrops and rounded whitish tips, creating inconspicuous upper wingbar. Nape paler gray brown with very fine blackish streaking. Ground color of underparts white, with buffy tinge to flanks and rarely to breast sides. Fine black-brown streaking on breast, breast sides, flanks, and often upper belly. White throat with or without fine black streaks or spots. Lateral throat stripe blackish, narrow but widening at bottom of throat; often very narrow or nearly absent at top. Wide jaw stripe white, bordered above by fine black whisker. Ear coverts pale brown or gray, with poorly defined rear border. Narrow eye ring, most conspicuous below, broken by thin black eye line, often obscure in front of eye. Long, broad supercilium varying from cream-gray to soft yellow, usually brightest above the lore. Brown-gray crown with finely black-streaked lateral stripes surrounding a narrow white median stripe, often unmarked at front of crown, finely and irregularly streaked at rear of crown. Rather slender bill dull pink, with irregular dark culmen and sometimes tip. Long tarsi and toes fairly bright pink, contrasting with white belly.
Juvenile: Buffier above, with less well-organized streaking. Underparts with more extensive tan-buff tinge, the streaking browner and less regular. Broad creamy-gray supercilium often with more conspicuous black streaks.
Though Linnaeus is credited with the name, these daring aerialists had been known to western science since the early sixteenth century. European sailors may well have encountered them at the end of the fifteenth, and surely the early human settlers of tropical ocean islands knew the birds from the very beginning.
European naturalists were introduced to the red-billed tropicbird by Fernández de Oviedo, who spent more than a decade in the West Indies; a concise version of his Historia general y natural de las Indias appeared in 1526. Oviedo writes that
“On the voyage to the Indies, certain white birds are seen, the size of a dove or larger. They are great fliers, and have long, very narrow tails; thus they call them ‘strawtails’. They are most often seen halfway or a little more on the journey to these regions.”
On his third trip west, Oviedo and his party saw one halfway between Spain and the Canaries. “All the sailors were greatly surprised and said that they had never seen or heard of one so close to Spain…. They are more often seen starting some 350 leagues off Hispaniola and Guadeloupe.”
Linnaeus never saw a living tropicbird anywhere, of course. But Oviedo’s report and the report of his successors over the next two centuries inspired one of the best names the Archiater ever came up with: Phaethon aethereus, the ethereal driver of the sun.