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The Thick-billed Raven (Corvus crassirostris) shares with the Common Raven the accolade of the largest in the family (60-64 cm in length) and indeed the largest of the bird order Passeriformes (perching birds). It has a very large bill that is laterally compressed and is deeply curved in profile giving the bird a very distinctive appearance. This bill is black with a white tip and has deep nasal grooves with only light nasal bristle covers.

All that commotion doesn't go unnoticed. The lammergeyer or Bearded Vulture, a massive bird soaring the mountain updrafts on wings two meters across. Despite their size, lammergeyers don't rush in to feed. They bide their time, letting others do the messy work. Only when the meal is almost over, do they make their move.

Lammergeyer literally means "lamb catcher", but these formidable birds aren't that interested in meat, what they prefer are bones. Bones as heavy as the bird itself are hauled off with ease. The lammergeyer knows precisely what to do with them. Bones away. With the bone shattered, the nutritious marrow is exposed. Chunks as big as your fist are dissolved in stomach juices as strong as an acid bath.

Bone-breaking takes skill and young birds need plenty of target practice. Many bones fall wide of the mark, others lack the height. It takes a full 7 years for a lammergeyer to get it right.

lammergeyer n.  [动] 髭兀鹰(产于亚欧)

 bide one's time vt. 等待时机

haul off v. 退却, 撤退

marrow n.  The inmost, choicest, or essential part; the pith.

实质，精华，精髓：最深层、最紧要或最必要的部分；精华
stomach juice n. 胃液 

acid bath n. 酸浴

get right v.  Understand accurately or do correctly