Chestnut-sided Warbler Habitat Model
go to: USFWS Gulf of Maine Watershed Habitat Analysis
go to: Species Table
Feedback: We welcome your suggestions on improving this model!

Draft Date:
March, 2001

Species:
Chestnut-sided warbler, Dendroica pensylvanica

Use of Study Area Resources:
Reproduction throughout study area. The breeding range of Chestnut-sided warblers is eastern North America, from southern Canada southward through the Appalachian Mountains to upper elevations in northern Georgia (Richardson and Brauning 1995).  Chestnut-sided warblers winter in Central America (DeGraaf and Rudis 1986).

Habitat Requirements:
Cover. Chestnut-sided warblers breed in open, early successional deciduous and mixed forest, or shrublands where there is a dense understory of shrubs or thick herbaceous vegetation, using either wetlands and uplands (Richardson and Brauning 1995). Typical habitats include regenerating clear-cuts, scrubby second-growth forests, woodland edges, powerline corridors, abandoned orchards, neglected pastures or cropland, brushy brooksides, and thickets of mountain laurel or American chestnut (Bent 1963, Chapman 1968, DeGraaf and Rappole 1995, Richardson and Brauning 1995, Mahoney et al.1997).  Abundance is related inversely to total basal area of trees, number of standing dead trees, and directly to percent cover by forest within 2 km of site (Robbins et al. 1989). Chestnut-sided warblers do not occur in built-up areas or active agriculture (Richardson and Brauning 1995). They may be common on islands (Palmer 1949).

Feeding. Chestnut-sided warblers are predominantly insectivorous, gleaning the twigs and the undersides of leaves for flies and caterpillars; they also take spiders and some fruit and seeds (Richardson and Brauning 1995).

Mortality data associated with studies at communications towers and tall smokestacks show that chestnut-sided warblers seem more likely than other species to have fatal collisions (Weir 1989, Graber et al. 1983, and Johnston and Haines 1957 in Richardson and Brauning 1995).

Model:
Habitat was mapped by selecting upland shrub, wetland deciduous shrub, powerline corridors, and oldfield cover types.  Upland and wetland deciduous and upland mixed forest cover within 30 m of these shrub/oldfield types also were included.  We then deleted portions of the habitat within 90 m of development or agriculture.

NWI Designations (wetlands only)	Cover Types	Cover Suitability (0 - 1 scale)
	Upland deciduous forest	1.0*
	Upland coniferous forest
	Upland mixed forest	1.0*
	Grassland
	Upland scrub/shrub	1.0
	Cultivated
	Developed
	Bare ground
PEM, L2EM	Lake/pond, emergent vegetation
PFOcon	Palustrine forest, conifer
PFOdec	Palustrine forest, deciduous	1.0*
PSSdec	Palustrine scrub shrub, deciduous	1.0
PSScon	Palustrine scrub shrub, conifer
PAB, L2AB	Lake/pond, aquatic vegetation
L1UB, PUB	Lake/pond, unconsolidated bottom
L2US	Lake, unconsolidated shore
L2RS	Lake, rocky shore
R1UB	Riverine subtidal unconsolidated
Rper	Riverine perennial
E1AB	Estuarine subtidal vegetated
E1UB	Estuarine subtidal unconsolidated bottom
E2AB	Estuarine intertidal algae
E2EM	Estuarine intertidal emergent
E2RS, R1RS	Estuarine, tidal river rocky shore
E2SS	Estuarine intertidal shrub
E2US	Estuarine intertidal unconsolidated shore
M1AB	Marine subtidal vegetated
M1UB	Marine subtidal unconsolidated bottom
M2AB	Marine intertidal algae
M2RS	Marine intertidal rocky shore
M2US	Marine intertidal unconsolidated shore
	Old fields and powerline corridors	1.0
NOTES	* Score if within 30 m of shrub/oldfield cover

Model testing: The chestnut-sided warbler occurrences from the Breeding Bird Survey (1997, 1998 data) were used to test the habitat map. We compared the presence of habitat near a random set of 797 upland points to that at which sparrows actually were observed. Of the 369 sites with birds, 342 had mapped habitat, while 644 sites out of the 797 randomly distributed sites had habitat. The Chi-square was highly significant, indicating that the overall model does indicate localities useful to chestnut-sided warblers.

Sources:
Bent, A.C. 1963. Life Histories of North American Wood Warblers. Dover Publications, New York, NY. Pp.367-379.

Chapman, F.M. 1968. The Warblers of North America. Dover Publications, Inc. NY.

DeGraaf, R.M. and J.H. Rappole. 1995. Neotropical Migratory Birds: Natural History, Distribution and Population Change. Comstock Publishing Associates, Ithaca, NY. 676 pp.

Mahony, N., E. Nol and T. Hutchinson. 1997. Food-chain chemistry, reproductive success, and foraging behaviour of songbirds in acidified maple forests of central Ontario. Can J. Zool. 75(4):509-517.

Palmer, R. 1949. Maine Birds. Bull. Of Comparative Zoology. Harvard College, Cambridge, MA. Pp. 471-473.

Robbins, C.R., D.K. Dawson and B.A. Dowell. 1989. Habitat area requirements of breeding forest birds of the middle Atlantic states. Wildl. Monogr. 103:1-34.

Richardson, M. and D.W. Brauning. 1995. Chestnut-sided Warbler, Dendroica pensylvanica. In A. Poole and F. Gill, (eds.) The Birds of North America, No. 190. The Academy of Natural Sciences, Philadelphia, and The American Ornithologists' Union, Washington, D.C.