Woodlands and Woodland Birds in IllinoisWoodlands and Woodland Birds in Illinois
Jeff BrawnJeff Brawn
University of Illinois at Urbana-ChampaignUniversity of Illinois at Urbana-Champaign
““Disturbance BirdsDisturbance Birds””
Species that have an importantSpecies that have an important
association with habitats that areassociation with habitats that are
created or maintained by some agent ofcreated or maintained by some agent of
disturbancedisturbance
For this Study:For this Study:
Savannas and Woodland:Savannas and Woodland: 20 to 20 to
80% canopy closure, not shrub80% canopy closure, not shrub
or grassland habitat, usuallyor grassland habitat, usually
dominated by oaks. Nearly alldominated by oaks. Nearly all
the sites visited were in thethe sites visited were in the
higher end of this rangehigher end of this range
Historical Range of Oak Savannas/WoodlandsHistorical Range of Oak Savannas/Woodlands
What bird species are associated with theseWhat bird species are associated with these
habitats?habitats?
For oak savannas and woodlands, mostFor oak savannas and woodlands, most
species are also found elsewhere (e.g.,species are also found elsewhere (e.g.,
forest, grassland, edges)forest, grassland, edges)
The Red-headed Woodpecker is anThe Red-headed Woodpecker is an
exceptionexception
Great Crested FlycatcherGreat Crested Flycatcher
Baltimore OrioleBaltimore Oriole
Northern BobwhiteNorthern Bobwhite
How are these species doing in Illinois?How are these species doing in Illinois?
For this, much of what is learned is from theFor this, much of what is learned is from the
Breeding Bird SurveyBreeding Bird Survey
Grassland Shrub-Scrub Savanna Forest Generalist
Habitat Groups
0
15
30
45
60
% in Category
Population Trends in North American BirdsBreeding Bird Survey: 1966-2006
Signif.
Decrease
Decrease Signif.
Increase
Increase
Red-headed WoodpeckerRed-headed Woodpecker
Region 22 (most of central and northernRegion 22 (most of central and northern
Illinois)Illinois)
For the Bird Conservation Area that IncludesFor the Bird Conservation Area that Includes
Much of Illinois: Oak Savanna and WoodlandMuch of Illinois: Oak Savanna and Woodland
BirdsBirds
Concern:Concern: Red-headed WoodpeckersRed-headed Woodpeckers
Great Crested Flycatcher Great Crested Flycatcher
Eastern Kingbird Eastern Kingbird
No No ProblemaProblema American Robin American Robin
Eastern Bluebird Eastern Bluebird
How does restoration change constituentHow does restoration change constituent
animal populations and communities?animal populations and communities?
Sampled in series of restored savannas pairedSampled in series of restored savannas paired
with undisturbed, closed-canopy forests.with undisturbed, closed-canopy forests.
-2 -1 0 1 2 3 4
0
10
20
30
40
50
% Frequency (DFA scores)
Illinois Oak Savanna and Forests
> Red-headed Woodpeckers, > Indigo buntings, > Baltimore Orioles
> Ovenbirds, > Scarlet Tanagers, > Red-eyed Vireos
Effects of Disturbance on Overall Community Structure
Disturbed
Undisturbed
Bird communities associated with savannas andBird communities associated with savannas and
open woodlands are identifiable and reasonablyopen woodlands are identifiable and reasonably
distinct from forest (or other) birddistinct from forest (or other) bird
communitiescommunities
The suite of species associated with theseThe suite of species associated with these
habitats are of serious conservation concernhabitats are of serious conservation concern
and have legitimate ecological identity.and have legitimate ecological identity.