Bearded reedling

Panurus biarmicus

SUBFAMILY

Paradoxornithinae

TAXONOMY

Parus biarmicus Linnaeus, 1758, Holstein. Three subspecies. Some classification systems have placed this species and other

Panurus biarmicus

I Resident parrotbills in separate family (Panuridae or Paradoxornithidae), but Delacour considered them subfamily within babblers. DNA hybridization research suggests they may belong in the same subfamily (Timaliinae) as most babblers.

OTHER COMMON NAMES

English: Bearded tit, marsh pheasant (East Anglia); French: Mesange a moustaches; German: Bartmeise; Spanish: Bigotudo.

PHYSICAL CHARACTERISTICS

5 in (12.7 cm). Highly sexually dimorphic. Male unmistakable: unique elongated black feathers in front of eye droop down to chest, forming a "moustache" that contrasts strikingly with orange eyes and bill; gray head, white throat, warm brown mantle, rump, and tail, black-white-and-brown-patterned wings, and black vent. Female: long-tailed, compact-bodied bird like male, with similarly patterned wings, and orange eyes and bill, but otherwise generally buffy-brown. Juvenile male very distinct: gray eyes set in black mask, black back, black on tail, and overall golden color. Legs black and unusually long.

DISTRIBUTION

Scattered range in British Isles and western and central Europe, then broadly across central and northeastern Asia to the Pacific (Bokai Sea). Accidental to Japan.

HABITAT

Wetlands, especially Phragmites reed beds. BEHAVIOR

European populations essentially nonmigratory, but inclined to wander in winter, and severe weather may cause wholesale relocations. East Asian populations appear to regularly migrate from interior to coast in winter. Highly gregarious and social outside of breeding season. Complex series of communication calls and displays. Usual flock size 10-20. Noted for skillful negotiation through reed beds, typically grasping a different stalk in each foot. Also capable of what Otto Koenig termed "flutter-swimming," should bird fall in water.

FEEDING ECOLOGY AND DIET

Remarkable seasonal changes in digestive tract. Winter diet largely Phragmites, Typha and rush Juncus) seeds. Stomach then muscular and hard-walled, and bird ingests numerous small stones. During remainder of year, when diet is mostly insects, spiders, and snails, stomach is smaller, flaccid, and contains no, or fewer, stones. Forages both on the ground and in vegetation.

REPRODUCTIVE BIOLOGY

Adapted to produce large numbers of offspring quickly, in response to relatively unstable environment. Regularly hatches three broods a year, sometimes four, and young from earliest clutch may themselves breed before end of season, in fall. Pairs mate for life, but nest in loose colonies without territorial boundaries. Nest is a deep cup of reed leaves and other plants, lined with reed flower-heads and feathers, located deep amidst plant stalks, above water, or on land, constructed by both members of pair, who continue to add material throughout 10-14 day incubation period. Four to eight pale, streaked, and speckled eggs incubated by both parents, who also raise chick together.

CONSERVATION STATUS

Not threatened, but distinctive, pink-bellied southern Turkish P. biarmicus kosswigi appears to be extinct. In early nineteenth century common along the Thames, from the estuary to Oxford, but British Isles population reduced to two to four pairs in East Anglia by 1948 due to marsh and fen draining, hard winters, and private and commercial egg collectors. Since then British population has increased to more than 500 pairs, at least partially recolonized from continental Europe during hard winter dispersals. German range has expanded since the 1950s. All European populations are closely monitored.

SIGNIFICANCE TO HUMANS

Since the 1990s large numbers were available cheaply from People's Republic of China for the captive-bird trade. Export prohibited by China in 2001, but may continue from Russian Federation. ♦

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