Scientific Name:
Melanerpes erythrocephalus
Nest Type: Cavity
Nest Location: Snag;
8-80'
Clutch Size: 3-7';
avg. 4-5
Food: Omnivorous
Foraging Guild:
Hawks, swoops, bark and foliage gleaner
The Red-headed Woodpecker
is a regular, summer resident in southern, central, and northwestern
regions of Minnesota (Janssen 1987). The species is a common spring
migrant in the southern part of the state; however, it decreases in
abundance in the more northern reaches of its range in Minnesota. Red-headed
Woodpeckers arrive in Minnesota from wintering grounds within the United
States from late March through May (Janssen 1987). Fall migration for
Red-headed Woodpeckers begins in early August and may continue through
late October.
The species is a regular
winter visitor in wooded portions of southern and central Minnesota,
becoming common in some areas (Janssen 1987). Christmas Bird Counts
in Iowa from 1951-1975 indicated an increase in the winter populations
of the species apparently due to an increased percentage of birds foregoing
migration and staying throughout the winter (Koenig 1977). Forest areas
dominated by oak, hickory, and maple are preferred habitat in winter,
and acorns comprise a large portion of the winter diet. During this
time, food is likely the limiting resource rather than cavities, and
interspecific aggression with Red-bellied Woodpeckers intensifies (Reller
1972).
In the south and central
portions of the state, Red-headed Woodpeckers primarily nest in open
deciduous woodlands; often in close proximity to clearings (Roberts
1932). In the northern regions, where forests become more contiguous
and coniferous in composition, the species is primarily found in recently
disturbed areas such as those created by forest fires (Niemi 1978) and
logging activity (Green and Niemi 1978). If they occur in logged areas,
the presence of snags is imperative for suitable nesting or feeding
habitat. In the Michigan breeding bird atlas project, the species showed
a clear preference for dry to mesic, open woodlands (Brewer et al. 1991).
Mature woodlots with high canopies, high basal areas, and open understories
have also been described as typical habitats (Connor and Adkinson 1977).
Competition with Starlings (Sturnus vulgaris) and Red-bellied
Woodpeckers (Melanerpes carolinus) for nesting cavities
is sometimes minimized by delaying nesting until later in the year (Ingold
1989).
Primary nest trees are
usually old snags without bark (Brewer et al. 1991). In addition, nest
trees are usually placed in a forest opening with the actual cavities
excavated in the bole of the tree rather in dead limbs of living trees
(Reller 1972, Short 1982). Red-headed woodpeckers show strong nest-site
fidelity, in part due to the longevity of their nesting cavities (Ingold
1991). Evans and Connor (1979) describe the optimal size of nest trees
as those 40-60 cm in diameter and 9 to 21 m high. They also suggest
that 200 suitable snags per 100 acres are necessary to maintain suitable
breeding populations, while wintering snag needs may be considerably
higher.
The diet of the Red-headed
Woodpeckers is varied, including insects, berries, seeds, nuts, and
mice; sap "wells" of Yellow-bellied Sapsuckers (Sphyrapicus varius)
may also be used (Terres 1987). At times of abundance, additional food
may be cached into crevices; however, Blue Jays and Starlings often
steal these reserves (Ehrlich et al. 1988, Roberts 1932). Also included
opportunistically in their diet are bird eggs, nestlings, and occasionally
adult birds (Martin 1960).
Red-headed woodpeckers
have been listed on the Audubon Society's Blue List from 1972 to 1986
due to a decline in their population. This decline may be due to the
loss of habitat. Management programs focusing on the species could reverse
this trend (Tate 1986).