After a long winter, this striking male long-tailed rosefinch (Carpodacus sibiricus) was fattening up on fresh willow seeds near the Tuul River.
And here’s the female. Although residents of Mongolia, these birds were likely passing through Ulaanbaatar on their way to higher elevations to the north. Rosefinches are mainly seed eaters. There are several species throughout the Northern Hemisphere.
Warmer temperatures are bringing flocks of new birds to Ulaanbaatar. These Bohemian Waxwings won’t stick around long; they’re on their way to nesting grounds in Siberia.
One day temperatures are in the 50’s or 60’s (in the teens, Celsius). The next day it’s below freezing with snowfall. And so it has been for the past few weeks from late March through mid-April. Welcome to Ulaanbaatar, Mongolia – officially recognized as the world’s coldest capital city. As transplants from Alaska, it feels like home – albeit a little warmer than our former north-of-the-Arctic-Circle village of Point Hope.
Pussy Willows – flowers of willow trees – have begun pushing out of their buds along the banks of Ulaanbaatar’s Tuul River.
Great tits, above and below, are common residents along the Tuul River as well as in the nearby mountain forests.
Such interesting little birds, all camouflage and color from the head to the mid-back, an abrupt line, and then symmetry from the mid-back through the tail, which, in nature, is its own form of camouflage.
Early morning frost turned the withered remnant of last fall’s flowers into frozen jellyfish.
By late morning, the sun had melted most of the frost…
…while in shaded pockets where snow still lingered, newly arrived long-tailed rosefinches filled up on last year’s store of seeds. The willows and grasses along the Tuul provide the perfect habitat for many species of birds. And, judging by tracks in the snow, rabbits as well.
Finches become acrobats in pursuit of a good meal.
As is typically the case among passerines, the colors of the female long-tails are subdued compared to their male counterparts.
Magpies were out in force, searching for nesting material to add to the massive jumbles of sticks they build in trees. It must work. They return to the same nests year after year, building them ever higher. Note the hooked beak; passerines beware. Magpies are predators, and no mistake.
The Tuul River green belt is our favorite place in Ulaanbaatar. In addition to providing habitat for year-round resident birds and summer nesters, the abundant seeds provide critical fuel for passerines migrating further north. The belt is also important hunting grounds for kestrels and other birds of prey as they make their way to their own nesting grounds. The banks of the Tuul are what’s left of an increasingly fragmented ecosystem. We’ve even caught fleeting glimpses of some type of quail or partridge in the thick willow undergrowth!
Corvids – a group which includes crows, ravens, rooks, jays, magpies and nutcrackers – fascinate. On a frigid December afternoon, we found them ice-fishing for caddis larvae in Mongolia’s Tuul River in the heart of Ulaanbaatar. (Click any of the photos for a larger view.)
The most intelligent of all birds, and with a brain-to-body-mass ratio rivaling that of the great apes and cetaceans, crows and their allies often exhibit remarkable behavior. Members of this family have been observed using and to some degree engineering purpose-specific tools – the only nonhuman animal other than the great apes to do so. There’s little doubt that certain feeding behaviors adopted by crows have been learned by watching other birds and animals.
Note the object in the beak of the crow on the left. It’s a caddis larva casing.
The Tuul River flows through Ulaanbaatar, Mongolia’s capital city. Despite urbanization, the river’s water quality remains high – good enough to support species of trout as well as sensitive aquatic insects such as mayflies, stoneflies and caddisflies – species which spend the early part of their lives as larvae on the bottoms of clean rivers and streams. The Tuul is fast-flowing. Consequently, despite weeks on end of sub-freezing temperatures, here and there pockets of water remain open over shallow, stony, silt-free bottom.
We took a cue from watching the crows and began scanning the ice for caddis larvae casings. As our eyes tuned into the proper size and shape, the empty husks appeared everywhere. This casing, constructed of tiny sticks and pebbles, is about 1.5 inches long (3.8 cm) and belonged to a member of the Northern case maker caddisfly family.
Perhaps the crows learned of the abundance of wintertime food in these areas of open water by watching dippers – a robin-sized bird that happily plunges into pools and riffles in all seasons in search of aquatic insects and small fish. In fact, on this day we saw a white-throated dipper submerge itself in one of the riffles where the crows were feeding and come up with a small fish.
Here a carrion crow (Corvus corone) has his prize – a caddis larva pried from its pebble and stick casing.
Not adapted to plunge into water, the crows were fishing from the edge of the ice – thus gaining access to water not overly deep, but deep enough to provide habitat for slow-moving caddis larvae. Resourceful birds, are crows.
Redpoll, (Acanthis flammea) Mongolian: Дөлөн цэгцүүхэй,
On a December morning with temperatures hovering around -13 degrees Farhenheit (-25 C) we fueled up with bacon and grits and walked from our apartment to the nearby Tuul River to check out the local bird scene.
Mist gently lifts from a patch of open water on Mongolia’s Tuul River. Along the shoreline to the right, frosted willows appear as sprays of white. In the background, dawn arrives on Ulaanbaatar, a rapidly growing city of just over one million inhabitants doing their best to stay warm with the country’s abundant coal.
Great tit, (Parus major) Mongolian: Их хөхбух
Relatives of the familiar chickadees of North America, these are one of the more common and colorful passerines in and around Ulaanbaatar.
Azure tit, (Parus cyanus) Mongolian: Номин хөхбух
Abundant but more shy than great tits, these beautiful little birds are seldom seen in the city itself, but we saw several during our walk along the Tuul.
We found two of these mitten-shaped nests – the work of white-capped penduline tits, (Remiz coronatus), (Бургасны ураншувуу). Like the buds of the tree it’s hanging from, the nest is dormant. Although the birds who made this nest will not use it again, male penduline tits, which arrive before females in the spring, use abandoned nests as indicators of suitable breeding habitat. Some Mongolians and other Asians hold a belief that these nests have medicinal powers – a belief unsupported by science – and collect them, a practice which has directly resulted in a decline in penduline tit numbers.
Eurasian tree sparrow, (Passer montanus) Mongolian: Хээрийн бор шувуу
Much like pigeons, tree sparrows seem to show up wherever humans live. Presumably these friendly little birds have essentially co-evolved with people. Within the city of Ulaanbaatar they occur in flocks in a variety of habitats. But along the Tuul River, their numbers thin as passerines more adept at thriving without the spoils of humans outcompete them. By the time one crosses the river and enters the forests of Bogd Kahn Mountain, tree sparrows are almost entirely replaced by tits, finches, nuthatches and other birds.
Eurasian (or common) magpie, (Pica pica) Mongolian: Алаг шаазгай
In urban settings magpies are often quite approachable, however the magpies along the Tuul proved wary. We worked to get this photo of a bird puffed up against the cold, a streak of emerald-green shimmering along the length of the tail. Generally scavengers and foragers, the magpie’s hooked beak is a tell-tale sign that it will assume the role of predator given the opportunity.
Carrion crows, (Corvus corone) Mongolian: Хар хэрээ
We found a group of crows targeting caddisfly larvae in a shallow riffle that hadn’t yet frozen, as is evident by the caddisfly casing in the beak of the bird on the left. The crows were using the edge of the ice to access this bounty. Perhaps they learned this behavior by observing dipper birds, a species that also frequents open water such as this during winter to feed on insects and small fish.
Scattered across the ice near the riffle where the crows were feeding, we found a number of empty caddis larvae casings. The larva that built this home from fragments of wood and tiny pebbles probably belongs to the Northern case maker group, family Limnephilidae. The fact that caddisflies are apparently abundant in this stretch of the Tuul indicates that despite urban development, water quality remains good.
White-throated dipper, (Cinclus cinclus) Mongolian: Гялааномруу хараацай,
Bee-like rapid wingbeats and an electric buzzing cry alerted us to the presence of a dipper bird near the same water the crows were using. What threw us was the flash of white as the bird zoomed by; in America and Japan we’d seen only brown dippers. This one disappeared under the icy water and came up with a fairly large minnow. Any day we can check off a new species is a good day.
The mix of willows, poplars, cottonwood and pines along the banks of the Tuul, as well as the river itself, constitute a biologically rich greenbelt in the heart of a rapidly growing city. Here’s to hoping that the citizens of Ulaanbaatar recognize what a treasure this is and insist on its protection.
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