N21
Acorn Woodpecker (Melanerpes formicivorus)
* length: 8 to 9½ in (20 to 24 cm);
* average weight: 3 oz (85 g);
* habitat: common in the western oak forests;
* quick identification: white eye surrounded by black; black surrounding bill; white cheeks and forehead; red on crown; pale yellow throat;
* identification tips: medium-sized woodpecker; white eye; black head; black area surrounding bill is in turn surroun-ded by white lower face, forehead, and throat; black chest, nape, back, and wings; white bases to outer primaries appear as small white crescent in flight; white rump; white belly and vent, with fine dark streaks on flanks; black tail; adult male: red cap extends back from white forehead; adult female: red cap at rear of head separated from white forehead by black area at top of head;
Seen in oak woods, pine-oak woodlands where oak trees are common, parks, towns. Found in small (2 to 15) noisy colonies. Drills holes in 'granary tree' in fall to store acorns. During summer eats mostly insects. The breeding habitat is forested areas with oaks in the hills of coastal California and the southwestern United States south to Colombia. Both sexes help with nest construction and both sexes tend young.
All members of an Acorn Woodpecker group spend large amounts of time storing acorns. Acorns typically are stored in holes drilled into a single tree, called a 'granary tree'. One granary tree may have up to 50,000 holes in it, each of which is filled with an acorn in autumn. The Acorn Woodpecker will also use human-made structures to store acorns, drilling holes in fence posts, utility poles, build-ings, and even automobile radiators; woodpeckers put 485 lb (220 kg) of acorns into a wooden water tank in Arizona.