Helmitheros vermivorum

Overall body plumage is grayish olive-green above, paler on abdomen, turning rich creamy buff on breast, throat and cheek. Two broad but strongly contrasted lateral crown stripes and a post-ocular stripe of blackish mouse-gray are separated by the same buff of the throat and cheek. Sexes are indistinguishable, although males tend to be larger than females. Young birds generally resemble adults but may have tertials lightly tipped with rusty brown (Ridgway 1902, Dwight 1975). Body length 11-12 cm (Ridgway 1902), wing length 66-75 mm, tarsus length 17.8-19.3 mm (Patton and Hanners, unpub. data). Eggs have a white background speckled with rust; 17.4 mm by 13.6 mm (Bent 1953). Song is similar to chipping sparrow (SPIZELLA PASSERINA) but sweeter and with chips rolling together. Chip note is sharp and strident.

Strongly streaked crown against olive-green body; often seen hopping and climbing on or hanging from shrub and subcanopy branches while foraging. Often forages in clusters of dead leaves, especially on wintering grounds.

BREEDING: Well-drained upland deciduous forests with understory patches of mountain laurel or other shrubs, drier portions of stream swamps with an understory of mountain laurel, deciduous woods near streams; almost always associated with hillsides (Gale 1995, Bushman and Therres 1988). Coastal plain habitats in Maryland include well-drained oak and oak-hickory forests, flatland white oak forests along river terraces, and drier islands of nontidal forested wetlands (Stasz 1996). Dense patches of shrubs or saplings may be an important component of territories (Patton and Hanners, unpub. data; Bushman and Therres 1988). Most abundant in mature woods but also may be common in young and medium-aged stands (see Bushman and Therres 1988). Nests on the ground, usually on hillsides, in cryptic nests among dead leaves, usually against roots or stems of shrubs or saplings, in a slight cavity (Harrison 1978), or up against rock outcrops. Nests are constructed of skeletonized leaves and lined with sporophyte stems of hairy cap moss (POLYTRICHUM sp.).

NON-BREEDING: In migration, occurs in various forest, woodland, scrub, and thicket situations, but specific habitat requirements are not known. In winter, inhabits undergrowth shrub and subcanopy layers of forests. Wunderle and Waide (1993) reported that worm-eating warblers are forest specialists but use a variety of forest types in the Caribbean, including "montane pine and broadleaf forest, wet limestone and dry forest, and dry scrub and residential habitats in the Bahamas." On the Caribbean slope of Central America, habitats include scrub and broadleaf and gallery forests (Rappole et al. 1983).

In Missouri, density was 2.13 males per 10 ha in continuous forest (Wenny et al. 1993). In Connecticut, density ranged from 4.46 males per 10 ha at a 300-ha TNC preserve to 0.26 per 10 ha at a wooded 56-ha site (Gale et al. 1997). Territorial in winter in Mexico (Rappole and Warner 1980); may forage in mixed-species flocks with resident, tropical forest birds (Greenberg 1987).

Eggs are laid in May, will lay replacement clutches through June. In the middle Atlantic region, nests from mid-May to mid-July (Bushman and Therres 1988). In Connecticut, extreme egg dates for first or subsequent clutches range from 13 May to 21 June, with nestlings last observed on 11 July (Patton and Hanners, unpub. data). Clutch size is 5-6 for first clutches; replacement clutch size is usually 4. Single-brooded. Incubation lasts 13 days, by females only. Young are brooded by the female and fed by both parents. Mean nestling duration is 8.5 days but young may fledge as early as day 5 if disturbed (Patton and Hanners, unpub. data).