Alouette de Raso

Identification

Found only on Raso Island of the Cape Verdes. Overall grayish-brown and moderately streaked including the breast. Note the large and heavy bill. Sometimes erects small crest. Belongs to the same genus as Eurasian Skylark, but is smaller with shorter wings and tail than Eurasian Skylark. Found along dry riverbeds on flat plains. Song is similar to that of Crested Lark. Call a short rattle, "Chureep."

Taxonomie

Originally, the Raso lark was classified as belonging to the genus Spizocorys. Formerly or presently, some authorities considered the Raso lark to belong to the genus Calandrella. Alternate names for the Raso lark include Cape Verde Islands lark, Raso Island lark, Raso short-toed lark and Razo skylark.

Nom scientifique

Alauda razae

Autorité

(Alexander, 1898)

Ordre

Passériformes

Famille

Alaudidés

Genre

Alauda

Répartition et habitat

The Raso lark is restricted in range to only Raso islet in the Cape Verde archipelago, although historically it is believed to have ranged over two other islands, Branco and São Vicente Island. All three of these islands were joined in the last ice age. Evidence from subfossil bone deposits reveal that the Raso lark once also existed on the islands of Santa Luzia, São Vicente, Santo Antão, and possibly Branco during the glacial times, before human colonization in the 15th century. Unfortunately, colonization was followed by a rapid extinction of local fauna. Raso islet itself has no permanent water and has never been inhabited by people, a fact that has probably saved the lark from extinction until now.<p>The island consists mostly of rocky desert with sandy parts in the west. Most Raso larks are found on level plains with volcanic soil and are associated with small vegetated patches along dry stream beds in which it feeds and breeds. Suitable breeding grounds on the island of Raso cover less than half of the island. The barren island suffers from frequent droughts which create dry plains that force the Raso larks to move across the island in search for food. Their most common areas of habitation are near dry river beds, but due to the scarcity of water, only patches of vegetation remain for Raso larks to reside in. Their nesting and feeding grounds consist of those same areas where vegetation is available. The Raso lark's sensitivity to drought has kept it endangered for several years due to the dry climate on the Cape Verde islands.

Migration

Espèce sédentaire

Comportement

Mode de migration: Espèce sédentaire.

Conservation

Tendance de la population: stable.

Tendance de la population

stable