On the upper verge of the pine forests, or in the scrubby vegetation just beyond, the following are not uncommon - black woodpecker (Picus martius), ring-ousel (Turdus torquatus), Bonelli's warbler (Phylloscopus Bonellii), crested tit (Parus cristatus), citril finch (Citrinella alpina), siskin (Chrysomitris spinus), crossbill (Loxia curvirostra), nutcracker (Nucifraga caryocatactes), blackcock (Tetrao tetrix), and the alpine varieties of the marsh-tit (Parus palustris, borealis) and tree-creeper (Certhia familiaris, costae).
The common crossbill of the Palaearctic region (Loxia curvirostra) is about the size of a skylark, but more stoutly built.
The first of these, of large stature, the parrot-crossbill (L.
The third, the two-barred crossbill (L.
Leucoptera) is the equivalent of the two-barred crossbill, but smaller.