Redpoll, (Acanthis flammea) Mongolian: Дөлөн цэзгцүүхэй,
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 хохбух
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 боршувуу
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: Апаг 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 харалай,
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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