0 the pine warbler , dendroica pinus , is a small songbird of the new world warbler family .
1 these birds have white bellies , white wing bars , dark legs and thin , relatively long pointed bills; they have yellowish lines over their eyes .
2  adult males have olive upperparts and bright yellow throats and breasts; females and immatures display upperparts which are olive-brown .
3  their throats and breasts are paler .
4 the song of this bird is a musical trill .
5  their calls are slurred chips .
6 their breeding habitats are open pine woods in eastern north america .
7  these birds are permanent residents in southern florida .
8  some of them , however , migrate to northeastern mexico and islands in the caribbean .
9  the first record for south america was a vagrant wintering female seen at vista nieve , colombia , on 20 november 2002; this bird was foraging as part of a mixed-species feeding flock that also included wintering blackburnian and tennessee warblers .
10 they forage slowly on tree trunks and branches by poking their bill into pine cones .
11  these birds also find food by searching for it on the ground .
12  these birds mainly eat insects , seeds and berries .
13 their nests are deep , open cups , which are placed near the end of a tree branch .
14  pine warblers prefer to nest in pine trees , hence their names .
