United States

Department of

Agriculture

Forest Service

Northeastern

Research Station

General Technical

Report NE-318

Atlas of Climate Change

Effects in 150 Bird Species of

the Eastern United States

Stephen N. Matthews

Raymond J. O’Connor

Louis R. Iverson

Anantha M. Prasad

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Publications, USDA Forest Service

359 Main Road

Delaware, OH 43015 USA
United States

Department of

Agriculture

Forest Service

Northeastern

Research Station

General Technical

Report NE-318

Atlas of Climate Change

Effects in 150 Bird Species of

the Eastern United States

Stephen N. Matthews

Raymond J. O’Connor

Louis R. Iverson

Anantha M. Prasad
Abstract

This atlas documents the current and potential future distribution of 150 common bird species

in the Eastern United States in relation to climate and vegetation distributions. Distribution

data for individual species were derived from the Breeding Bird Survey (BBS) from 1981 to

1990. Regression tree analysis was used to model the BBS data as functions of contemporary

environmental variables. These predictor variables included the abundance of 68 tree species as

determined by USDA Forest Service's Forest Inventory and Analysis data, as well as 8 climate

variables and 4 elevation variables. The model for each bird species is described. These models

were then projected onto two scenarios of global climate change for which future distributions

of the climate variables and tree species had previously been calculated. This allowed

comparison of the future habitat for each bird species against its current modeled distribution.

Summary statistics of the current and projected range and abundance within the Eastern United

States are included. Depending on the global climate model used, as many as 78 bird species are

projected to decrease by at least 25 percent, while as many as 33 species are projected to increase

in abundance by at least 25 percent.

The Authors

STEPHEN N. MATTHEWS was a graduate student at the University of Maine, Orono, and is

currently at The Ohio State University, Columbus, Ohio (matthews.204@osu.edu)

RAYMOND J. O'CONNOR is professor of wildlife ecology at the University of Maine, Orono

(oconnor@apollo.umenfa.maine.edu)

LOUIS R. IVERSON is a research landscape ecologist with the USDA Forest Service,

Northeastern Research Station, Delaware, Ohio (liverson@fs.fed.us)

ANANTHA M. PRASAD is an ecologist with the USDA Forest Service, Northeastern Research

Station, Delaware, Ohio (aprasad@fs.fed.us)

Photo Credits

Kevin T. Karlson provided the majority of the species photographs. R. G. Potts supplied the

Gray Partridge photo; Michael Danzenbaker, the Chimney Swift; and Brian E. Small provided

the Common Loon, Acadian Flycatcher, Mississippi Kite, Evening Grosbeak, Purple Finch,

Bank Swallow, Warbling Vireo, Yellow-throated Vireo, Golden-winged Warbler, Cerulean

Warbler, Blackburnian Warbler, Mourning Warbler, Yellow-breasted Chat, Brown-headed

Nuthatch, and Bachman's Sparrow. All rights are reserved by these photographers. Front cover

landscape photos were provided by Louis Iverson.

Published by: For additional copies:

USDA Forest Service USDA Forest Service

11 Campus Blvd. STE 200 Delaware, OH 43015

Newtown Square, PA 19073-3200 Fax: 740-368-0152

September 2004
Acknowledgments

We gratefully acknowledge the efforts of all those who contributed to this atlas. We particularly

thank Mary Boda, who formatted this document and provided valuable suggestions on improving

the atlas. Partial funding for this publication was provided by the College of Natural Sciences,

Forestry, and Agriculture, the Department of Wildlife Ecology, and the Office of the Vice President for Research at the University of Maine.

Atlas of Climate Change Effects in 150 Bird Species of

the Eastern United States

Contents

Part I -Atlas Explanation

Introduction ............................................................................................................... 1

Data Sources and Methods ........................................................................................ 2

Atlas Format and Explanation .................................................................................... 6

Summary .................................................................................................................... 9

Literature Cited ........................................................................................................10

Key to Species Pages .................................................................................................13

Part II -Bird Species

Species Pages .............................................................................................................16

Part III -Interpretations

Species Interpretations .......................................................................................... 319

Index by Common Name ........................................................................................... 337
Part I:

Atlas Explanation
GTR NE-318~ Atlas of Climate Change Effects in 150 Bird Species of the Eastern United States 1

Introduction

Present-day bird communities occupy a variety of habitats across North America. Changes in these

habitats, including those induced by climate change, could dramatically alter the composition and

distribution of these communities. There is mounting evidence that increases in greenhouse gases

during the last 50 years have contributed greatly to the warming of the Earth's climate (IPCC 2001),

and to changes in the behavior of numerous organisms (Parmesan et al. 1999; Thomas and Lennon

1999; Moss et al. 2001; Walther et al. 2002). More importantly, rapid and dramatic changes in the

Earth's climate over the next century are anticipated following continued increases of greenhouse

gases (IPCC 2001).

Several studies provide evidence of strong correlations between climate and the distribution patterns

of birds (Ashmole 1963; Currie 1991; Root 1988). Using associations between climate variables and

birds, Price and Glick (2002) and Price and Root (2001) assessed the potential for large shifts in

range of numerous bird species in the conterminous United States. Price and Root (2001) predicted

significant losses of neotropical species throughout the Nation due to shifts in their range.

Investigating the effect of drought sensitivity on populations of waterfowl, Sorenson et al. (1998)

predicted significant reductions in the populations of 14 migratory bird species throughout the

Prairie Pothole Region that extends from north-central Iowa to southeastern Alberta, Canada. In

South Africa, Erasmus et al. (2002) projected reductions in range for nearly 80 percent of the 179

species studied -- including 38 species of birds.

Bird distributions are influenced not only by the surrounding climate but also by the availability of

suitable habitat, which, in turn, is influenced by climate change. Thus, it is possible that climate

and habitat envelopes of a species disassociate under climate change such that the availability of

suitable habitat may be more limiting than fluctuations in climate. This possibility has not been

considered in previous studies of distribution shifts. In this atlas we have incorporated both climate

variables and tree-species distributions (to quantify habitat availability) to model the current

distribution patterns of 150 common bird species in the Eastern United States. These

environmental relationships can help researchers gain a more complete understanding of the factors

underlying current distribution patterns and aid in determining the potential effect of climate

change on future patterns.

To the extent that a shift in distribution enables a species to remain within the bounds of identified

environmental constraints (as climate change progresses), our predictions should be valid. This

would not be true should that species adapt to climate change through changes in environmental

requirements. Our model assumes that changes in the future distribution of trees under climate

changes have essentially equilibrated by the end of the present century. However, lag times

associated with tree migration (Iverson et al. 1999b; Schwartz et al. 2001) and tree longevity,

particularly of those in refugia, could result in distributions that differ significantly from those

projected on the basis of our assumptions.

This atlas follows a similar one developed for 80 common tree species in the Eastern United States

(Iverson et al. 1999a). (An updated version of the tree atlas is available at http://www.fs.fed.us/ne/

delaware/atlas/). Here we use available data on the current distribution of the 150 bird species to

generate a predictive model of the species abundance. The models of the species abundance allowed

us to identify the environmental variables that show associations with the species distribution.

Then we use these relationships to predict the species models onto two scenarios of global climate

change: the Canadian Climate Center model (CCC) (Boer et al., 2000; Kittel et al., 2000) and the

Hadley (U.K.) Center for Climate Prediction and Research model (Hadley) (Mitchell et al. 1995).

We chose these 2xCO2

 models because they span the spectrum of potential climate change. For each

bird species we predicted the change in distribution that would occur should a species continue to track

current climate and habitat envelopes.
2 GTR NE-318 ~ Atlas of Climate Change Effects in150 Bird Species of the Eastern United States

Data Sources and Methods

This atlas covers the United States east of the 100th meridian. Bird data were obtained from the national

Breeding Bird Survey (BBS), a population monitoring program conducted annually since 1966 in the

United States and Canada. Currently, the BBS is administered jointly by the U.S. Geological Survey's

Patuxent Wildlife Research Center, Laurel, Maryland, and the Canadian Wildlife Service. The BBS

generates data from nearly 4,000 routes across North America (Robbins et al. 1989; Sauer et al. 1997).

In a review of the BBS, O'Connor et al. (2000) concluded that the survey met its goals with only minor

biases. After extracting 1,223 representative routes that had been surveyed frequently from 1981 to 1990,

O'Connor et al. (1996) determined the incidence value (proportion of surveys along a route in which a

bird was recorded) for each of the 150 species. For our purposes, incidence values are interpreted as

absolute abundance given the typical relationship between incidence and abundance for most organisms

(e.g., Hanski 1992; Maurer 1990). Yang et al. (1995) interpolated the incidence value to obtain an

abundance surface over the conterminous United States for each species, using White et al.'s (1992) 640

km2

 hexagonal grid with 12,600 points.

For the present analysis, we identified the hexagons east of the 100th meridian, then cross-walked the bird

data for each hexagon to a U.S. county map using an area-weighting technique (Matthews et al. 2002).

This enabled us to match the environmental data from the county-based tree atlas (Iverson and Prasad

1998; Iverson et al. 1999a). Incidence values for birds ranged from 0.0 to 1.0. Species with a value less

than 0.05 were considered absent from a county.

The environmental data included eight climate and four elevation variables, and Importance Values (IV)

for 80 tree species (of which 68 tree variables occurred in the bird models) (Table 1). As a measure of

abundance, IV's incorporate the number of stems and basal area of a species relative to those variables for

all species in a county (Iverson and Prasad 1998). For the climate data, potential future conditions for the

years 2070 to 2099 were projected onto the CCC and Hadley scenarios as mapped to the counties of the

Eastern United States. We also obtained data for the projected future habitat (under CCC and Hadley) of

the 68 tree species listed in this atlas. The use of individual tree-species abundances allowed us to track the

projected movement of habitat for each bird species for each climate scenario. Because it is anticipated

that tree species will migrate independently to form new vegetation communities following climate

change (Davis 1989; Webb III 1992), it would have been inappropriate to use current vegetation

communities as predictors of bird species abundance. In practice, most bird species were mapped

successfully with respect to the distributions of a small number of individual tree species; that is, either

individual tree species were effective surrogates of forest-community properties or the birds were not

sensitive to community properties.

The entire set of potential predictors provide a wide array of environmental variables (Table 1) that a

priori evidence indicated might be associated with the abundance patterns of bird species. By building

contemporary models in terms of climate and vegetation variables that were available spatially both for

contemporary conditions and future conditions (see examples, Fig. 1), we could predict future bird

distributions assuming only that the contemporary relationships between birds and climate and vegetation

did not change in the future and that climate change follows the CCC or Hadley scenarios.

To generate representative statistical models of the bird species abundance based on available data, we used

regression tree analysis (Breiman et al. 1984; Clark and Pregibon 1992). Traditional methods require

normality and rely on strict linear relationships between the bird data and the environmental data.

Regression tree procedures do not require normality, are less sensitive to outliers, and can handle

interactions between variables by subsetting the data in the tree-building process without the need to

identify all possible interactions a priori (Verbyla 1987; Clark and Pregibon 1992; Iverson and Prasad

1998). A regression tree proceeds by recursively partitioning the sample into groups defined by the

predictor variables. The resulting regression tree was then pruned back using ten-fold cross-validation

(Breiman et al. 1984; Clark and Pregibon 1992) to protect against overfitting of the model. These groups
GTR NE-318~ Atlas of Climate Change Effects in 150 Bird Species of the Eastern United States 3

Table 1. --Environmental data and importance values (iv) for 68 tree species that occurred in

the models for 150 bird species. The frequency and percent columns indicate, respectively, the

number and percentage of the 150 bird species for which that variable appeared in the

regression tree model

Abbreviation Variable Frequency Percent

Climate Variables

JANT Mean January temperature (oC) 85 56.7

PET Potential evapotranspiration (mm/month) 46 30.7

JULT Mean July temperature (oC) 54 36.0

PPT Annual precipitation (mm) 62 41.3

AVGT Mean annual temperature (oC) 52 34.7

MAYSEPT Mean May-September temperature (oC) 42 28.0

JUL.JANT Seasonality: difference between JULT and JANT (oC) 71 47.3

JARPPET July-August ratio of precipitation to PET 28 18.7

Elevation

MAX.ELV Maximum elevation (m) 49 32.7

MIN.ELV Minimum elevation (m) 37 24.7

avg.ELV Average elevation (m) 35 23.3

ELV.CV Elevation coefficient of variation 24 16.0

Trees Species Importance Values

iv12 Balsam fir (Abies balsamea) 39 26.0

iv68 Eastern redcedar (Juniperus virginiana) 4 2.7

iv110 Shortleaf pine (Pinus echinata) 5 3.3

iv111 Slash pine (Pinus elliottii) 7 4.7

iv121 Longleaf pine (Pinus palustris) 2 1.3

iv125 Red pine (Pinus resinosa) 1 0.7

iv129 Eastern white pine (Pinus strobus) 10 6.7

iv131 Loblolly pine (Pinus taeda) 13 8.7

iv222 Pond cypress (Taxodium distichum var. nutans) 3 2.0

iv241 Northern white-cedar (Thuja occidentalis) 7 4.7

iv261 Eastern hemlock (Tsuga canadensis) 16 10.7

iv313 Boxelder (Acer negundo) 1 0.7

iv315 Striped maple (Acer pensylvanicum) 10 6.7

iv316 Red maple (Acer rubrum) 21 14.0

iv317 Silver maple (Acer saccharinum) 1 0.7

iv318 Sugar maple (Acer saccharum) 7 4.7

iv371 Yellow birch (Betula alleghaniensis) 14 9.3

iv372 Sweet birch (Betula lenta) 12 8.0

iv375 Paper birch (Betula papyrifera) 13 8.7

iv391 American hornbeam (Carpinus caroliniana) 2 1.3

iv400 Hickory (Carya spp. ) 11 7.3

iv402 Bitternut hickory (Carya cordiformis) 4 2.7

iv403 Pignut hickory (Carya glabra) 3 2.0

iv407 Shagbark hickory (Carya ovata) 2 1.3

iv409 Mockernut hickory (Carya tomentosa) 2 1.3

iv461 Sugarberry (Celtis laevigata) 2 1.3

iv462 Hackberry (Celtis occidentalis) 2 1.3

iv471 Eastern redbud (Cercis canadensis) 2 1.3

iv491 Flowering dogwood (Cornus florida) 4 2.7

 continued
4 GTR NE-318 ~ Atlas of Climate Change Effects in150 Bird Species of the Eastern United States

iv500 Hawthorn (Crataegus spp. ) 2 1.3

iv521 Common persimmon (Diospyros virginiana) 3 2.0

iv531 American beech (Fagus grandifolia) 9 6.0

iv540 Ash (Fraxinus spp. ) 2 1.3

iv541 White ash (Fraxinus americana) 16 10.7

iv543 Black ash (Fraxinus nigra) 8 5.3

iv544 Green ash (Fraxinus pennsylvanica) 5 3.3

iv591 American holly (Ilex opaca) 7 4.7

iv602 Black walnut (Juglans nigra) 1 0.7

iv611 Sweetgum (Liquidambar styraciflua) 3 2.0

iv621 Yellow-poplar (Liriodendron tulipifera) 18 12.0

iv641 Osage-orange (Maclura pomifera) 1 0.7

iv653 Sweetbay (Magnolia virginiana) 1 0.7

iv691 Water tupelo (Nyssa aquatica) 5 3.3

iv693 Blackgum (Nyssa sylvatica) 11 7.3

iv694 Swamp tupelo (Nyssa biflora) 4 2.7

iv711 Sourwood (Oxydendrum arboreum) 8 5.3

iv743 Bigtooth aspen (Populus grandidentata) 3 2.0

iv746 Quaking aspen (Populus tremuloides) 12 8.0

iv762 Black cherry (Prunus serotina) 8 5.3

iv802 White oak (Quercus alba) 10 6.7

iv812 Southern red oak (Quercus falcata var. falcata) 4 2.7

iv813 Cherrybark oak (Quercus falcata var. pagodaefolia) 2 1.3

iv820 Laurel oak (Quercus laurifolia) 4 2.7

iv823 Bur oak (Quercus macrocarpa) 2 1.3

iv826 Chinkapin oak (Quercus muehlenbergii) 4 2.7

iv827 Water oak (Quercus nigra) 2 1.3

iv830 Pin oak (Quercus palustris) 1 0.7

iv832 Chestnut oak (Quercus prinus) 9 6.0

iv833 Northern red oak (Quercus rubra) 9 6.0

iv835 Post oak (Quercus stellata) 6 4.0

iv837 Black oak (Quercus velutina) 6 4.0

iv901 Black locust (Robinia psuedoacacia) 1 0.7

iv931 Sassafras (Sassafras albidum) 6 4.0

iv951 American basswood (Tilia americana) 1 0.7

iv970 Elm (Ulmus spp. ) 4 2.7

iv971 Winged elm (Ulmus alata) 8 5.3

iv972 American elm (Ulmus americana) 9 6.0

iv975 Slippery elm (Ulmus rubra) 1 0.7

Table 1. --cont.

Abbreviation Variable Frequency Percent

are increasingly homogenous with respect to the response variable. The resulting model contains a series

of decision rules that define each of these groups relative to thresholds of environmental predictors. The

predictors, in turn, lead to predictions of the bird-species incidence as the average of the species abundance

(incidence) in the counties contained in the terminal nodes.

We use the white-eyed vireo (Fig. 2) to illustrate the modeling procedure and the types of results obtained

from this analysis. For this species, the first split occurred at the average January temperature of -2.4°C.

The 873 counties (43 + 250 + 580) with temperatures below the threshold are segregated into the left

branch where they are split again by the occurrence of yellow-poplar. The right split resulted in a terminal

node (the bird data could not be split further by the predictors) of 43 counties with high abundance of
GTR NE-318~ Atlas of Climate Change Effects in 150 Bird Species of the Eastern United States 5

Figure 1. --Maps of three predictor variables plotted under current conditions and

as modified by the CCC and Hadley scenarios. Variables in this example include

average January temperature (°C), average precipitation (mm), and importance

value (abundance) of balsam fir.
6 GTR NE-318 ~ Atlas of Climate Change Effects in150 Bird Species of the Eastern United States

yellow-poplar and a predicted incidence of 0.543, i.e., the vireo was typically recorded 54 percent of the

time on the BBS routes in this region. Moving back to the right side of the root split, that is, the counties

with January temperatures exceeding the -2.4°C threshold, the same logic applies on following the branch

down to the four rightmost terminal nodes.

Atlas Format and Explanations

This Atlas provides information on the current and potential future distribution of 150 common bird

species in the Eastern United States. Two pages are devoted to each species and include tables and maps

related to the current status of the bird in the Eastern United States, and to the model developed to project

the bird's future distribution under climate change. Also included are a map of current abundance based

on BBS data, the regression tree model relating species abundance to environmental variables, a map of

modeled current distribution, a map of the bird's geographic dependence on environmental variables, and

statistics for the model goodness of fit. Two additional maps show species distributions projected under

the two future climate scenarios and a third map shows the distribution of changes in abundance

projected from the current distribution.

Distribution Statistics

Each species account includes distribution statistics that were interpreted as follows:

Area-weighted incidence

Average species incidence within each county was weighted by the county area and summed across all

counties with at least one occurrence. Incidence is the proportion of surveys at a location at which a

species was recorded and typically is highly correlated with abundance (Hanski 1992; Maurer 1990).

Species incidence is based on the probability of a bird species being encountered along a BBS route during

the breeding season. Observers would stop every half mile along a 25-mile roaded route and look and

listen for 3 minutes. Compiled over 10 years (1981-1990), the resulting average incidence value gives a

respresentive picture of each species' abundance. Therefore, we assume that the area-weighted incidence

can be interpreted as a measure of the absolute abundance of that species in the Eastern United States.

Figure 2. --Regression tree structure of the model for white-eyed vireo. Values at each branch

end refer, respectively, to predicted species incidence and number of counties in that branch,

and a key for locating those counties on the geographic predictors map. JANT is average

January temperature (°C), JUL.JANT is average seasonality (difference between July and

January average temperatures °C), iv621 is abundance of yellow-poplar, iv131 is abundance of

loblolly pine, and iv129 is abundance of eastern white pine.
GTR NE-318~ Atlas of Climate Change Effects in 150 Bird Species of the Eastern United States 7

Ranked area-weighted incidence

Used to rank each species in descending order of average incidence within its eastern range. For species

with the same abundance value, the mean rank of the tied values was assigned and rounded to the nearest

integer (values thus range from 1 to 150).

Range

The total area of the species' range in the Eastern United States (km2 x 1,000) as determined by the BBS

data at the county resolution. Range was determined by summing the areas of counties in which a species

was present (incidence greater than 0.05).

Ranked Range

The rank in descending order of the range size of the species (values ranged from 1 to 150).

Breeding Status

As described by Gough et al. (1998) and included here as background information, species are classified as

a resident, short-distance migrant, or neotropical migrant. Patterns of migration and residency vary

widely among species and influence species response to changes in climate. The breeding status of the first

20 species in this atlas (all waterfowl) was not classified by Gough et al. For these we followed Ehrlich et

al. (1988) and Alsop (2001) in classifying them as resident, migrant, or partial migrant.

Primary Breeding Diet

Using the classification described in Ehrlich et al. (1988), the species' primary breeding diet is represented

as insects, aquatic invertebrates, small mammals, fish, carrion, omnivorous, seeds, greens, fruits, or nectar.

Birds often rely on a variety of food throughout the year and the classification here represents their

primary source only during the breeding season.

Deviance Explained by Predictors

Percent deviance of species incidence explained by each variable in the model was calculated to quantify

the relative importance of each of the environmental variables. These were then summed to obtain the

overall goodness of fit of the model.

Predicted Response for CCC and Hadley Scenarios

The decision rules obtained from the regression tree models were used to project the species abundance

onto the CCC and Hadley climate scenarios. This projection was accomplished by changing the values of

the predictor variables from contemporary values to those of CCC and Hadley and then reapplying the

decision rules of the species models to calculate the new potential distributions.

Abundance Change

The percentage change between the current and projected future abundance. This was obtained as

( )

100

( )

×

⎥

⎥

⎥

⎦

⎤

⎢

⎢

⎢

⎣

⎡ −

=

∑

∑

i

i i

i

i i i

w a

w b a

P

where P is the percentage change in species incidence; i is the county identifier; wi is the weighted area of

the county in the study area; ai is the current species incidence ranging from 0.0 to 1.0, and bi

is the

predicted species incidence under the future climate scenario.

Total Range Change

Expresses the area of the projected future range of a species as a percentage of its current range

within the Eastern United States. Note that this total is the combination of range lost and range

gained and might conceal information on potential shifts in range. For example, a low value might
8 GTR NE-318 ~ Atlas of Climate Change Effects in150 Bird Species of the Eastern United States

indicate that the species is little affected by climate change, or that large areas of its current range are

abandoned but offset by corresponding gains elsewhere. We provide separate estimates for range lost

and range gained to allow one to distinguish between these two cases.

Range lost

The percentage of the current range of the species that no longer will be occupied under climate

change despite potential gains elsewhere in the Eastern United States.

Range gained

The potential gain in area as a percentage of its current range despite potential losses elsewhere.

Differences in CCC and Hadley Scenarios

The CCC and Hadley scenarios represent two separate projections following a doubling of carbon

dioxide, and, therefore, differ in predictions of the response of bird species to climate change. The

histogram presented for each species identifies the frequency distribution of the within county

differences between the projected species incidences under CCC and Hadley. Where outcomes are

similar for both scenarios (CCC minus Hadley approximate zero), there is greater agreement and

certainty as to the pattern of change anticipated.

Regression Trees and Modeled Current Distribution

Regression tree analysis was used to generate a predictive model for each species. The regression tree

algorithm selects the predictor variables that best delineate the species incidence at each point in the

regression tree. The location of the counties in the models can be identified in the geographic

predictor maps by matching the id number in the regression tree diagram with the map legend. For

77 bird species, the model was too complex to present in full on a single page. Thus, these models

omit the least important nodes. The geographic predictors maps were similarly simplified, though

the calculation of range and of abundance changes were computed with the complete model.

Maps

The atlas includes three maps that depict species current distribution and three that show the spatial

distribution of the species' predicted response to climate change. All maps are produced at the

county resolution using ARC/INFO (ESRI 1993).

Current BBS

Shows the current distribution of species east of the 100th meridian, by county, according to the

BBS data for 1981-90. Values for species incidence range from 0.0 to 1.0. Values below 0.05 are

included on the map but were excluded from subsequent quantitative analyses due to potential

rounding errors.

Thus if you went to a county shaded in the 0.2-0.4 incidence range (during the breeding season),

you might expect a 20 to 40% chance of seeing or hearing the bird if you stopped for 3 minutes

every half mile along the 25-mile BBS routes within the county.

Modeled current

Shows current distribution as reconstructed by the regression tree model. Spatial distribution was

reconstructed by applying the decision rules in the species model to the mapped predictor data.

This was accomplished for each county by following the tree diagram to a terminal node and

assigning to the county the predicted incidence of that node.

Geographic predictors

This map is linked directly to the regression tree diagram for each species. Its legend keys the map

to the end-node id numbers that identify a terminal branch of the tree. By following the decision

rules that determine the terminal node, one can identify the counties that meet the specified criteria,
GTR NE-318~ Atlas of Climate Change Effects in 150 Bird Species of the Eastern United States 9

thus providing an understanding of how the environmental variables in the model divide the study

area, and how different environmental conditions are associated with the abundance of the species

across its distribution.

Predicted CCC

Shows the predicted distribution for the CCC climate scenario. As with the modeled current map,

decision rules from the regression tree model were applied to a dataset that contained environmental

data, in this case, information characterizing projected future conditions of counties under the CCC

scenario.

Predicted Hadley

Prepared in the same way as CCC map but using the conditions predicted under the Hadley

scenario. Because there is considerable uncertainty as to the actual extent of climate change, using

the Hadley and CCC scenarios provides a range of possible outcomes as well as a more complete

understanding of the uncertainty surrounding the response of bird species to global climate change.

Potential shifts

Summarizes the potential response of bird species to CCC and Hadley. The first column indicates

the direction and magnitude of change between the modeled current and predicted incidence under

CCC, the second column shows the corresponding differences under Hadley. The corresponding

map color indicates the location at which that particular combination of CCC and Hadley

projections occur. A plus sign indicates a projected increase in species incidence in that county of at

least 10 percent, a minus sign indicates a decrease of at least 10 percent. A zero indicates no

projected shift (did not change by more than 10 percent). This scheme allows one to quickly

visualize where CCC and Hadley show agreement and disagreement with respect to potential

changes in the distributions of bird species.

Summary

This atlas contains detailed information on traits and biogeographic factors contributing to current

and potential future range and abundance for 150 individual bird species common in the Eastern

United States. In this section we consider the broader response of all the species collectively in their

possible response to projected climate change. These models predict major shifts in many bird

species ranges and abundance in the Eastern Unites States under both the CCC and Hadley GCM

scenarios (Table 2).

As shown in Table 2, about half of the species show a potential decrease of at least 25% of their

abundance (species incidence) with either GCM model, while about a fifth of the species show a

potential increase of at least 25% in their abundance. With respect to potential area changes in

range, roughly 40% of the species will likely decrease while about 20% would likely increase in area

by at least 25% following climate change (Table 2). Because the CCC scenario is more severe relative

Table 2. --Number (and percentage) of bird species potentially increasing

or decreasing in abundance and area by at least 25% according to our

models driven by the CCC and Hadley GCM scenarios

Increase by >25% Decrease by > 25%

Scenario Abundance Area Abundance Area

CCC 33 (22%) 31 (21%) 78 (52%) 60 (40%)

Hadley 28 (19%) 24 (16%) 75 (50%) 56 (37%)
10 GTR NE-318 ~ Atlas of Climate Change Effects in150 Bird Species of the Eastern United States

to the Hadley scenario (hotter and drier), the models also show slightly greater effects on species

outcomes from the CCC scenario. By subtraction, we see that 26-31% of the species evaluated

would have small (<25%) changes in abundance and 39-47% of the species would have small range

changes after climate change.

For those species modeled to decrease by at least 25%, there were 18-19 more species modeled to be

reduced in abundance than in area. These species are likely to continue to occupy large portions of

their current ranges while undergoing substantial changes in their abundance. It is important to

emphasize that Canada was not part of this model exercise so that many of the species projected to

decrease in area and abundance will be compensated for by new territory potentially occupied in

Canada.

These summaries provide a broader perspective on the potential changes of bird species distributions

due to climate change. From our models, we see many of the species that currently occupy the

northern portion of the Eastern United States moving north out of our study area and into Canada,

and many species currently restricted to the south expanding their range or shifting their abundance

core northward. While each species has its own unique model and the potential to move

independently in response to climate change, their responses can be viewed as patterns of change.

By assessing the collective response of climate changes across a broad array of bird species, we have

the ability to gain further insight into potential future distribution of birds, in general, within the

Eastern United States.

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Iverson, L. R.; Prasad, A. M.; Schwartz, M. W. 1999b. Modeling potential future individual treespecies distributions in the Eastern United States under a climate change scenario: a case

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Maurer, B. A. 1990. The relationship between distribution and abundance in a patchy

environment. Oikos. 58: 181-189.

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Parmesan, C.; Ryrholm, N.; Stefanescu, C.; Hill, J. K.; Thomas, C. D.; Descimon, H.; Huntley, B.;

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Price, J. T.; Root, T. L. 2001. Climate change and neotropical migrants. In: Rahm, J.; McCabe,

R, eds. Changing climates of North America: political, social, and ecological: transactions of the

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American birds that migrate to the neotropics. Proceedings of the National Academy of

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Root, T. 1988. Environmental factors associated with avian distributional boundaries. Journal

of Biogeography. 15: 489-505.

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Breeding Bird Survey results and analysis. Version 96.4. Laurel, MD: Patuxent Wildlife

Research Center.

Schwartz, M. W.; Iverson, L. R.; Prasad, A. M. 2001. Predicting the potential future distribution

of four tree species in Ohio, USA, using current habitat availability and climatic forcing.

Ecosystems. 4: 568-581.

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warming on waterfowl populations breeding in the northern great plains. Climatic Change.

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Walther, G.; Post, E.; Convey, P.; Menzel, A.; Parmesan, C.; Beebee, T. J. C.; Fromentin, J.; HoeghGuldberg, O.; Bairlein, F. 2002. Ecological responses to recent climate change. Nature. 416:

389-395.

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produce national biodiversity estimates. Computing Science & Statistics. 27: 405-409.
GTR NE-318~ Atlas of Climate Change Effects in 150 Bird Species of the Eastern United States 13

GTR NE-xxx ~ Atlas of Climate Change Effects of 150 Bird Species of the Eastern United States 3

The tree diagram identifies the variables and thresholds in the species model. The values at each branch

end refer (respectively) to the predicted species incidence, the number of counties in that branch, and a

key locating these counties on the Geographic Predictors map (facing page). Number of counties

Species incidence (CCC minus Hadley)

Comparison of Differences Between Two Scenarios

Dickcissel

Spiza americana Species Interpretation Page 333

Distribution Statistics

Abundance (area-weighted incidence) 0.674

Ranked abundance 40

Range (km2

 x 1000) 1765

Ranked range 66

Breeding status neotropical migrant

Primary breeding diet insects

Percent Deviance Explained by Predictors

Variables (n=10) R2

Acer rubrum (iv316) 43.4

July-August ratio of precipitation to PET

 (JARPPET) 19.1

Difference July-January temp. (JUL.JANT) 5.5

Potential evapotranspiration (PET) 3.0

Mean July temp. (JULT) 3.0

Carya sp. (iv400) 2.1

Carya cordiformis (iv402) 1.6

Ulmus alata (iv971) 1.5

Pinus taeda (iv131) 1.3

Mean May-September temp. (MAYSEPT) 1.1

Total R2 81.6

Predicted Response for Two GCM Scenarios (%)

CCC Hadley

Abundance change* 78.5 54.0

Range lost 1.7 9.6

Range gained 76.7 54.5

Total change in range 75.0 44.9

* percentage change from original value

4 GTR NE-xxx ~ Atlas of Climate Change Effects of 150 Bird Species of the Eastern United States

see tree diagram

(facing page)

Dickcissel

I

J

K

G

H

F

E

C

B

A

D

Key to Species Pages

This atlas provides information on the current and potential future

distribution of 150 common bird species in the Eastern United States.

Two pages are devoted to each species and include tables and maps

related to the current status of the bird in the Eastern United States,

and to the model developed to project the bird's future distribution

under climate change. The following brief descriptions provide

information on these two pages; further details can be found in the

preceding pages.

Map Page

F. Current BBS -- Shows the current distribution, by

county, according to the BBS data for 1981-90. Values for

species incidence range from 0.0 to 1.0 (present in 100% of the

surveys). Values below 0.05 are included on the map but were

excluded from subsequent quantitative analyses due to potential

rounding errors.

G. Modeled Current -- Shows current distribution as

reconstructed for each county by the regression tree model.

H. Geographic Predictors -- Linked directly to the

regression tree diagram (“E”), this map's legend keys to the endnode id numbers that identify a terminal branch of the tree. By

following the decision rules that determine the terminal node,

you can identify the counties that meet the specified criteria,

how the environmental variables in the model divide the study

area, and how different environmental conditions are associated

with the abundance of the species across its distribution.

I. Predicted Hadley -- Shows the predicted distribution

for the Hadley climate scenario, derived using the regression tree

model, but with projected future climate and vegetation

variables. Although the projected time for the Hadley climate is

year 2100, because of lag times with trees, equilibrium with the

new climate would not be expected for many years beyond 2100.

Because of uncertainty as to the extent of future climate change,

using both Hadley and CCC scenarios provides a range of

possible outcomes as well as a more complete understanding of

the uncertainty surrounding the response of bird species to

global climate change.

J. Predicted CCC -- Prepared in the same way as Hadley

map but using the conditions predicted under the CCC scenario.

K. Potential Shifts -- Summarizes the potential response

of bird species to CCC and Hadley. The first column indicates a

positive (+), a negative (-), or no (0) difference of at least 10

percent between the modeled current and predicted incidence

under CCC. The second column shows the corresponding

differences under Hadley. Thus, you can quickly visualize where

CCC and Hadley show agreement and disagreement with

respect to potential changes in the distributions of bird species.

Summary Data Page

A. Area-weighted Incidence --(0-1 scale) is the average

incidence (proportion of BBS surveys which recorded the species)

weighted by county area from those counties with at least 1

occurrence. It is highly correlated with abundance of the species

throughout the study area. Ranked abundance refers to the species

rank relative to all other species, ranging from 1 being the most

abundant to 150. Range and ranked range refer to the total area

occupied by the species, as calculated from summing the areas of

counties where the species was present with an incidence above

0.05. Breeding status refers to patterns of migration and residency of

the species, and can be resident, short-distance migrant, neotropical

migrant, or partial migrant (for 20 waterfowl species). Primary

breeding diet represents the species' primary source of food during

the breeding season, and can be insects, aquatic invertebrates, small

mammals, fish, carrion, omnivorous, seeds, greens, fruits, or nectar.

B. Deviance Explained by Predictors -- Percent deviance

of species incidence explained by each variable in the model was

calculated to quantify the relative importance of each of the

environmental variables. These were then summed to obtain the

overall goodness of fit of the model.

C. Predicted Response for Future Scenarios -- After

building the regression tree models for current distribution for each

species, the current climate variables were swapped with CCC and

Hadley future (year 2100) climate variables to model potential

future bird species abundance and range. The future projections

assume equilibrium with climate and vegetation and would

represent a time far beyond the year 2100. Abundance change is the

percentage change between the current and projected future

abundance. Total range change is the area of the projected future

range of a species as a percentage of its current range. Note that this

total is the combination of range lost and range gained which

accounts for the situation where changes in one part of the range

may be offset by opposite changes in another part of its range.

D. Differences in CCC and Hadley Scenarios -- This

graph shows the agreement between the two scenarios in future

abundance projections. For these histograms the minimum number

of counties necessary for a bar is 25. If most of the >2000 counties

have a value near 0 (CCC minus Hadley approximate zero), both

scenarios indicate similar future distribution changes. If not, the

disagreement is larger between scenarios and the uncertainty with

future climate also leads to uncertainty with bird distributions.

E. Regression Trees and Modeled Current

Distribution -- Regression tree analysis was used to generate

the predictive models. It selects the predictor variables that best

delineate the species incidence at each end point in the regression

tree. The location of the counties in the models can be identified in

the geographic predictor map (Map H) by matching the id number

in the regression tree diagram with the map legend. For 77 of the

150 species, the model contained too many branches to present in

full on a single page, so the tree was "pruned" for publication.
GTR NE-318 ~ Atlas of Climate Change Effects in 150 Bird Species of the Eastern United States 15

Part II:

Bird Species
Common Loon, Gavia immer

Ring-billed Gull, Larus delawarensis

Laughing Gull, Larus atricilla

Black Tern, Chlidonias niger

Mallard, Anas platyrhynchos

Blue-winged Teal, Anas discors

Canada Goose, Branta canadensis

White Ibis, Eudocimus albus

American Bittern, Botaurus lentiginosus

Great Blue Heron, Ardea herodias

Great Egret, Ardea alba

Snowy Egret, Egretta thula

Little Blue Heron, Egretta caerulea

Cattle Egret , Bubulcus ibis

Green Heron , Butorides virescens

Yellow-crowned Night-Heron,

Nyctanassa violacea

Sora, Porzana carolina

American Coot, Fulica americana

Common Snipe, Gallinago gallinago

Spotted Sandpiper, Actitis macularia

Killdeer , Charadrius vociferus

Gray Partridge, Perdix perdix

Northern Bobwhite, Colinus virginianus

Ruffed Grouse, Bonasa umbellus

Ring-necked Pheasant, Phasianus

colchicus

Rock Dove, Columba livia

Mourning Dove, Zenaida macroura

Common Ground-Dove, Columbina

passerina

Turkey Vulture, Cathartes aura

Black Vulture, Coragyps atratus

Mississippi Kite, Ictinia mississippiensis

Northern Harrier, Circus cyaneus

Red-tailed Hawk, Buteo jamaicensis

Red-shouldered Hawk, Buteo lineatus

Broad-winged Hawk, Buteo platypterus

American Kestrel, Falco sparverius

Great Horned Owl, Bubo virginianus

Yellow-billed Cuckoo, Coccyzus

americanus

Black-billed Cuckoo, Coccyzus

erythropthalmus

Downy Woodpecker, Picoides pubescens

Yellow-bellied Sapsucker, Sphyrapicus

varius

Pileated Woodpecker, Dryocopuc pileatus

Red-headed Woodpecker, Melanerpes

erythrocephalus

Red-bellied Woodpecker, Melanerpes

carolinus

Chuck-Will’s Widow, Caprimulgus

carolinenis

Whip-poor-will, Caprimulgus vociferus

Common Nighthawk, Chordeiles minor

Chimney Swift, Chaetura pelagica

Ruby-throated Hummingbird,

Archilochus colubris

Species listed in the standard taxonomic order followed by the American Ornithologists Union (AOU)

Scissor-tailed Flycatcher, Tyrannus

forficatus

Eastern Kingbird, Tyrannus tyrannus

Eastern Phoebe, Sayornis phoebe

Eastern Wood-Pewee, Contopus virens

Acadian Flycatcher, Empidonax virescens

Willow Flycatcher, Empidonax traillii

Least Flycatcher, Empidonax minimus

Horned Lark, Eremophila alpestris

Blue Jay, Cyanocitta cristata

American Crow, Corvus brachyrhynchos

Fish Crow, Corvus ossifragus

European Starling, Sturnus vulgaris

Bobolink, Dolichonyx oryzivorus

Brown-headed Cowbird, Molothrus ater

Yellow-headed Blackbird,

Xanthocephalus xanthocephalus

Eastern Meadowlark, Sturnella magna

Orchard Oriole, Icterus spurius

Baltimore Oriole, Icterus galbula

Brewer’s Blackbird, Euphagus

cyanocephalus

Evening Grosbeak, Coccothraustes

vespertinus

Purple Finch, Carpodacus purpureus

House Finch, Carpodacus mexicanus

American Goldfinch, Carduelis tristis

Vesper Sparrow, Pooecetes gramineus

Savannah Sparrow, Passerculus

sandwichensis

Grasshopper Sparrow, Ammodramus

savannarum

White-throated Sparrow, Zonotrichia

albicollis

Chipping Sparrow, Spizella passerina

Clay-colored Sparrow, Spizella pallida

Field Sparrow, Spizella pusilla

Darkeyed junco, Junco hyemalis

Bachman’s Sparrow, Aimophila aestivalis

Song Sparrow, Melospiza melodia

Lincoln’s Sparrow, Melospiza lincolnii

Swamp Sparrow, Melospiza georgiana

Eastern Towhee, Pipilo erythrophthalmus

Northern Cardinal, Cardinalis cardinalis

Rose-breasted Grosbeak, Pheucticus

ludovicianus

Blue Grosbeak, Guiraca caerulea

Indigo Bunting, Passerina cyanea

Painted Bunting, Passerina ciris

Dickcissel, Spiza americana

Summer Tanager, Piranga rubra

Purple Martin, Progne subis

Cliff Swallow, Petrochelidon pyrrhonota

Barn Swallow, Hirundo rustica

Tree Swallow, Tachycineta bicolor

Bank Swallow, Riparia riparia

Cedar Waxwing, Bombycilla cedrorum

Loggerhead Shrike, Lanius ludovicianus

Red-eyed Vireo, Vireo olivaceus

Warbling Vireo, Vireo gilvus

Yellow-throated Vireo, Vireo flavifrons

Blue-headed Vireo, Vireo solitarius

White-eyed Vireo, Vireo griseus

Black-and-white Warbler, Mniotilta varia

Prothonotary Warbler, Protonotaria citrea

Worm-eating Warbler, Helmitheros

vermivorus

Blue-winged Warbler, Vermivora pinus

Golden-winged Warbler, Vermivora

chrysoptera

Nashville Warbler, Vermivora ruficapilla

Northern Parula, Parula americana

Yellow Warbler, Dendroica petechia

Black-throated Blue Warbler, Dendroica

caerulescens

Yellow-rumped Warbler, Dendroica coronata

Magnolia Warbler, Dendroica magnolia

Cerulean Warbler, Dendroica cerulea

Blackburnian Warbler, Dendroica fusca

Yellow-throated Warbler, Dendroica

dominica

Black-throated Green Warbler,

Dendroica virens

Pine Warbler, Dendroica pinus

Prairie Warbler, Dendroica discolor

Ovenbird, Seiurus aurocapillus

Northern Waterthrush, Seiurus

noveboracensis

Kentucky Warbler, Oporornis formosus

Mourning Warbler, Oporornis philadelphia

Common Yellowthroat, Geothlypis trichas

Yellow-breasted Chat, Icteria virens

Hooded Warbler, Wilsonia citrina

Canada Warbler, Wilsonia canadensis

American Redstart, Setophaga ruticilla

House Sparrow, Passer domesticus

Northern Mockingbird, Mimus polyglottos

Gray Catbird, Dumetella carolinensis

Brown Thrasher, Toxostoma rufum

Carolina Wren, Thryothorus ludovicianus

House Wren, Troglodytes aedon

Winter Wren, Troglodytes troglodytes

Sedge Wren, Cistothorus platensis

Brown Creeper, Certhia americana

White-breasted Nuthatch, Sitta

carolinensis

Red-breasted Nuthatch, Sitta canadensis

Brown-headed Nuthatch, Sitta pusilla

Tufted Titmouse, Baeolophus bicolor

Black-capped Chickadee, Poecile

atricapillus

Blue-gray Gnatcatcher, Polioptila

caerulea

Wood Thrush, Hylocichla mustelina

Veery, Catharus fuscescens

Swainson’s Thrush, Catharus ustulatus

Hermit Thrush, Catharus guttatus

American Robin, Turdus migratorius
GTR NE-318~ Atlas of Climate Change Effects in 150 Bird Species of the Eastern United States 317

Part III:

Species Interpretations
318 GTR NE-318 ~ Atlas of Climate Change Effects in150 Bird Species of the Eastern United States
GTR NE-318~ Atlas of Climate Change Effects in 150 Bird Species of the Eastern United States 319

Species Interpretations

This section focuses on specific features of the results for individual bird species. It is likely that

many species will respond similarly to climate change: the southern limits of northern species

will move north under warming climatic conditions or indirectly through dependence on tree

species that themselves are limited by warming conditions. The reverse is true of the northern

limits of southern species. As a result, many birds show similar patterns in distribution change.

A second source of similarity originates in the differences between the CCC and Hadley

scenarios. In the Eastern United States, CCC projects a hotter and drier climate, while Hadley

projects a wetter and only slightly warmer climate. Also, CCC projects more dramatic

distribution changes (often shifts northward) than Hadley both for birds and trees. As another

example, regional changes along the Atlantic Coast occur with Hadley but not with CCC. Thus,

rather than repeat essentially the same comments, we often characterize species response as that

of a northern or southern species. The extent of the difference between the two scenarios by

county, is depicted in the histogram provided on each species page.

It also is important to emphasize that when we use the words "project" or "predict" in the

following text, we mean that our models -- both the tree models from Iverson et al. (1999a) and

the bird models represented here -- show these outputs with no set date associated with them.

With the 2xCO2 scenarios of CCC and Hadley, the changed climate is expected to occur by the

end of this century. However, biological organisms, especially trees, have long lag times such

that it could be another hundred years or more before the full impact of these changes in

climate on species distributions would be observed. Thus, when using the terms project or

predict, we mean the habitat and not necessarily the actual distribution of the organisms are

modeled to change, by the end of this century.

From our analysis, there is no way to differentiate whether a predictor variable that helps

describe and map a bird species is actually a driving variable for the bird (a specific ecological or

physiological relationship) or is a coincidentally correlated variable not related to the bird's

distribution. In the following discussion, we have attempted to identify those models that

appear to be blatantly coincidentally correlated, but it is inevitable that some portion of the

remaining predictor variables in the tree diagrams will actually be only coincidentally correlated.

In the section that follows, bird species are listed in the standard taxonomic order followed by

the American Ornithologists Union (AOU), though species also are listed alphabetically at the

end of this atlas. Using the AOU format allows the normal scientific practice of placing accounts

of taxonomically related species close to each other. Related species often share similar ecological

features and this order results in the most interesting distributional comparisons being between

relatives. For additional information on the projections for tree species discussed in this section,

see Iverson et al. (1999a).
320 GTR NE-318 ~ Atlas of Climate Change Effects in150 Bird Species of the Eastern United States

Common Loon

(Gavia immer)

Map section page 16

Projections for this species, with CCC predicting

extirpation from the Eastern United States, are

almost certainly overestimates. The common

loon has no known ecological dependence on

paper birch or on balsam fir despite the

contemporary correlation of the bird and these

tree species. The latter are strongly favored by

specific soil conditions and the presence of clays,

and these conditions are likely to be correlated

with the topography and lake types frequented

by breeding loons. Because paper birch and

balsam fir are projected to migrate northward,

our model projects a major contraction in the

loon's range. However, the actual contraction in

range and numbers will be smaller than

estimated here and confined to lakes affected by

the loon's association with January

temperatures.

Ring-billed Gull

(Larus delawarensis)

Map section page 18

Although well modeled in the northern

distribution of this wetland species, our model

failed to capture patches of low incidence in the

South. In fact, this model produced one of our

least successful outcomes for variance explained.

As is true for many wetland species, the habitat

of the ring-billed gull is sensitive to summer

heat and to rainfall patterns, and both CCC and

Hadley project major reductions in range and

abundance.

Laughing Gull

(Larus atricilla)

Map section page 20

For this species, which is highly sensitive to

elevation, both CCC and Hadley project little

overall change, but a marked decrease in

abundance along the North Carolina coast,

Florida, and Louisiana due to a secondary

dependence on winter temperatures.

Black Tern

(Chlidonias niger)

Map section page 22

Although predicting well for the northern part

of its distribution, our model failed to predict

known breeding populations in Nebraska, Iowa,

and Michigan. This implies that the

distribution of this species is sensitive to

variables other than those in our model, which

is dominated by temperature variables. Both

CCC and Hadley project a northward retreat

and total or nearly complete extirpation of the

species in the Eastern United States.

Mallard

(Anas platyrhynchos)

Map section page 24

Both CCC and Hadley project a marked

contraction northward in the range of this

temperature-sensitive species, as well as a

significant loss of high-density populations. The

model overgeneralized contemporary occurrence

in the South, where the mallard is absent

according to BBS data.

Blue-winged Teal

(Anas discors)

Map section page 26

Although our model captured the northern core

of the population, it failed to capture certain

populations in the South, which is influenced

by seasonality. Both CCC and Hadley project a

contraction in range toward the northwest.

Canada Goose

(Branta canadensis)

Map section page 28

This species depends heavily on average

temperature and both CCC and Hadley project

a contraction northward. However, the Canada

goose currently is expanding in range and

abundance due to human activities, which

could outweigh future climate-change

phenomena and thus affect future distribution.

Our model failed to capture contemporary

small populations across the Carolinas, Georgia,

and Tennessee.

White Ibis

(Eudocimus albus)

Map section page 30

Our model projects expansion northward for

this species, which is dominated by winter

temperatures. Hadley projects increases in

population density and a minor expansion in

range, while CCC projects a 150-percent

expansion in range into North Carolina,

Tennessee, Arkansas, and Oklahoma.
GTR NE-318~ Atlas of Climate Change Effects in 150 Bird Species of the Eastern United States 321

American Bittern

(Botaurus lentiginous)

Map section page 32

This northern wetland species is limited

primarily by January temperatures. A weak

dependence on the distribution of balsam fir

probably is a surrogate for soil conditions.

CCC predicts total extirpation in the Eastern

United States; Hadley allows for local

persistence in Minnesota, North Dakota, and

northern New England.

Great Blue Heron

(Ardea herodias)

Map section page 34

Both CCC and Hadley project major decreases

in abundance in the Great Lakes States despite

the absence of causal links between vegetation

predictors in our model and the ecology of the

great blue heron. Thus, the possibility of

artifact due to confounding variables cannot be

dismissed.

Great Egret

(Ardea alba)

Map section page 36

This largely southern species apparently is

limited by winter temperatures, though our

model failed to capture its presence in South

Dakota, Minnesota, and Wisconsin. CCC and

Hadley project expansion northward and to the

northwest (as far as Pennsylvania with CCC and

as far as Kansas with Hadley).

Snowy Egret

(Egretta thula)

Map section page 38

This southern species, limited by elevation and

winter temperatures, is projected to expand

northward under both CCC (250 percent) and

Hadley (120 percent). The snowy egret's

incidence could decrease locally along the Gulf

and Atlantic Coasts under CCC, though few

counties will be affected (see histogram).

Little Blue Heron

(Egretta caerulea)

Map section page 40

Another southern species limited by winter

temperatures, the little blue heron is projected

to expand northward under both CCC and

Hadley; expansion under CCC is twice that of

Hadley.

Cattle Egret

(Bubulcus ibis)

Map section page 42

This species is particularly abundant along

the Gulf Coast, with scattered populations

along the Atlantic Coast into New Jersey.

Because of its strong sensitivity to

temperature, the cattle egret is projected to

expand northward as far as the Great Lakes

States under CCC. Local differences in

temperatures between CCC and Hadley

resulted in significant differences in projected

abundances between the two climate

scenarios (see histogram).

Green Heron

(Butorides virescens)

Map section page 44

No change is range for this widespread

species is projected by CCC or Hadley.

However, the green heron is projected to

increase in abundance in the northern half of

the United States as the result of its

dependence on average temperature.

Yellow-crowned Night-Heron

(Nyctanassa violacea)

Map section page 46

This southern species apparently is limited

along the northern edge of its range by low

winter temperatures. Both CCC and Hadley

project expansion northeast through the

Atlantic States from Georgia to New Jersey.

CCC projects additional expansion

throughout Alabama and Georgia and into

Tennessee and Kentucky.

Sora

(Porzana carolina)

Map section page 48

Our model captured the core of the species

distribution in the northwestern portion of

the study area, but failed to predict its

occurrence in several counties in Maine and

in the Gulf States. The sora relies on

wetlands and January-July temperatures

influence our model. Both CCC and Hadley

predict significant contraction in range

northward.
322 GTR NE-318 ~ Atlas of Climate Change Effects in150 Bird Species of the Eastern United States

American Coot

(Fulica americana)

Map section page 50

Our model captured the core of the species

distribution in the northwestern portion of

the study area where the influence of the

January-July temperature range is dominant,

but it failed to predict the occurrence in

pockets of peripheral counties and in the Gulf

States. Both GCM scenarios predict a drastic

contraction in range northward.

Common Snipe

(Gallinago gallinago)

Map section page 52

Both CCC and Hadley predict a retreat

northward due primarily to this species'

dependence on average temperature. Total or

nearly complete extirpation from the Eastern

United States is predicted by CCC and

Hadley, respectively.

Spotted Sandpiper

(Actitis macularia)

Map section page 54

Both CCC and Hadley predict a retreat

toward the Canadian border (farther north

with CCC).

Killdeer

(Charadrius vociferus)

Map section page 56

Both CCC and Hadley project little or no

change in the range of this widespread species.

However, there are projected increases in

density toward its south and southeastern

edges as well as some contraction in density

within the core of the killdeer's range.

Gray Partridge

(Perdix perdix)

Map section page 58

Both CCC and Hadley predict a shift in the

range of this species in the Eastern United

States to areas in North Dakota and

Minnesota. CCC also projects near extirpation

of the gray partridge from the United States.

These projections are based on the shifts in

the July-September temperature range and

potential evapotranspiration.

Northern Bobwhite

(Colinus virginianus)

Map section page 60

Both CCC and Hadley predict expansion

northward for this temperature-dependent

species. These scenarios also project partial

(Hadley) or complete (CCC) colonization

along the Canadian border, where the

northern bobwhite currently is absent.

Ruffed Grouse

(Bonasa umbellus)

Map section page 62

Both CCC and Hadley predict the

withdrawal of this species from the coastal

regions of the Northeast and from the

southern portion (Hadley) or the entire

(CCC) Great Lakes region. This loss would

follow the near extirpation of paper birch over

most of the Eastern United States, i.e., buds

of this tree are a major component of the diet

of the ruffed grouse in the northern part of its

range.

Ring-Necked Pheasant

(Phasianus colchicus)

Map section page 64

Our model slightly overgeneralized areas of

low density, resulting in a contemporary

distribution that includes northern

Minnesota, Michigan's Upper Peninsula, and

parts of northern Vermont, New Hampshire,

and Maine. Both CCC and Hadley project a

northern shift in distribution, greater under

CCC but ameliorated by Hadley for this

precipitation-sensitive species. CCC's

predicted expansion to Georgia and Florida is

unlikely due to local ecological conditions

that we were unable to model.

Rock Dove

(Columba livia)

Map section page 66

Neither CCC nor Hadley project changes in

the range of this species. However, there is a

projected redistribution in numbers

throughout the Eastern United States,

resulting in net losses in abundance. The

climate scenarios differ with respect to how

individual counties will be affected.
GTR NE-318~ Atlas of Climate Change Effects in 150 Bird Species of the Eastern United States 323

Mourning Dove

(Zenaida macroura)

Map section page 68

Little response to climate change is projected

for this ubiquitous, temperature-dependent

species except for minor population increases in

northern Minnesota, Wisconsin, and

Michigan's Upper Peninsula. These are areas in

which balsam fir is expected to decrease in

abundance. Habitat studies indicate that the

mourning dove is more common in coniferous

forests dominated by pine than fir.

Common Ground-Dove

(Columbina passerina)

Map section page 70

Largely associated with the distribution of slash

pine, in which this species occurs primarily in

open, scrubby areas, the common ground-dove

is correspondingly limited to the Southeastern

United States. Both CCC and Hadley project

major population reductions in Florida, with

expansion along the northern edge of the bird's

range. CCC predicts expansion as far north as

Kentucky and southern Missouri.

Turkey Vulture

(Cathartes aura)

Map section page 72

The substantial variation in the regional

abundance of this species is reflected in the

different projections by CCC and Hadley. Both

climate scenarios predict an increase in

abundance in areas where turkey vulture

populations are low, particularly along a belt

from southern Oklahoma to North Carolina.

CCC predicts a wider belt northward and

population increases and range expansion from

Iowa to the north and northeast and in New

York and New England.

Black Vulture

(Coragyps atratus)

Map section page 74

This species decreases in density northward

from the Gulf Coast in response to winter

temperatures. Both CCC and Hadley project

extensive expansion northward as well as an

increase in abundance. The projected range of

the vulture extends from South Dakota to

Pennsylvania (CCC) or from Kansas to Virginia

(Hadley).

Mississippi Kite

(Ictinia mississippiensis)

Map section page 76

This species shows a strong correlation with

July temperatures but also is associated with the

distribution of hackberry and water tupelo. The

latter is indicative of bottomland forests in the

Southern United States. Substantial increases in

range are predicted by CCC (from Iowa into

West Virginia) and Hadley (from Tennessee

northward). We view this large expansion and

the "jumping over" a broad center belt as a

modeling artifact.

Northern Harrier

(Circus cyaneus)

Map section page 78

The distribution of this species is primarily a

function of seasonality, precipitation, and the

abundance of quaking aspen. Both CCC and

Hadley project a contraction in range in New

England and population reductions in the

northwest, particularly in areas where Iverson et

al. (1999a) project reductions in the abundance

of aspen. In Wisconsin, aspen provides nesting

cover for the northern harrier and the bird's

density is reduced where aspen populations

have been reduced. CCC predicts colonization

of Florida resulting from changes in

precipitation, but concerns related to habitat

and competition likely will preclude

widespread colonization.

Red-tailed Hawk

(Buteo jamaicensis)

Map section page 80

Both CCC and Hadley project substantial

increases in abundance, particularly across

the northwestern and central portions of the

Eastern United States. Small losses are

projected in Nebraska (CCC) and along the

Piedmont (Hadley).

Red-shouldered Hawk

(Buteo lineatus)

Map section page 82

Both CCC and Hadley project expansion

northward for this species, which is dependent

on winter temperatures. CCC projects

expansion to South Dakota through Michigan;

Hadley projects expansion to Kansas and

northern Missouri. Losses in abundance are

confined to the counties along the Gulf Coast.
324 GTR NE-318 ~ Atlas of Climate Change Effects in150 Bird Species of the Eastern United States

Broad-winged Hawk

(Buteo platypterus)

Map section page 84

CCC projects a general decrease in abundance

while Hadley projects an increase in

abundance. Both scenarios predict a shift in

range with losses in northern areas; CCC also

predicts considerable losses in Louisiana and

Mississippi due to a decrease in precipitation.

Dominant predictors for this species in

addition to annual precipitation are the

abundance of red maple and maximum

elevation. Projected increases in precipitation

in the southern areas by Hadley correspond to

predicted increases in the broad-winged hawk

along the southeastern coastal region and

Mississippi River (from Mississippi to

Tennessee).

American Kestrel

(Falco sparverius)

Map section page 86

Both CCC and Hadley predict considerable

losses in abundance from southern Michigan,

Minnesota, Wisconsin, Indiana, Ohio, and

Kentucky, with smaller losses throughout the

Northeast. Population gains are projected in

the Western States under both scenarios, with

Hadley also projecting increases along the

Appalachian Mountains in Virginia, West

Virginia, and North Carolina. Both scenarios

project an expansion in range throughout the

Gulf States.

Great Horned Owl

(Bubo virginianus)

Map section page 88

Little change is projected for the eastern

populations of this species under CCC and

Hadley as neither dominant predictor (red

maple and elevation) will shift with climate

change. The areas of increased abundance are

most concentrated in Iowa, Minnesota, and

South Dakota.

Yellow-billed Cuckoo

(Coccyzus americanus)

Map section page 90

Both CCC and Hadley project an increase in

abundance from South Dakota to Maryland

and along the Appalachians to North

Carolina. This increase closely parallels

predicted shifts in the dominant predictor in

our model (average temperature). The

predicted increase in Florida corresponds to a

change in seasonality.

Black-billed Cuckoo

(Coccyzus erythropthalmus)

Map section page 92

Both scenarios predict a contraction of this

species to the north. Our model is dominated

by winter temperatures, and CCC

correspondingly projects the black-billed cuckoo

to retreat farther north to remain within a

suitable climate envelope. Note that it is the

summer breeding distribution that is correlated

with winter temperature, so the distributional

constraint is indirect and may be dependent on

the bird's insect diet.

Downy Woodpecker

(Picoides pubescens)

Map section page 94

Both CCC and Hadley project a loss in

abundance in the southern portion of the range

of this species, which is influenced by annual

precipitation. However, these losses are offset by

predicted population gains to the north.

Yellow-bellied Sapsucker

(Sphyrapicus varius)

Map section page 96

This species is dominated by the abundance of

balsam fir, which it often uses for nesting. CCC

projects total extirpation of the sapsucker from

the Eastern United States in conjunction with

the predicted extirpation of balsam fir. Hadley

predicts continued persistence in balsam fir

remnants along the Great Lakes and in northern

New England.

Pileated Woodpecker

(Dryocopus pileatus)

Map section page 98

CCC predicts population gains from eastern

Iowa north to Michigan and across to New York

and Massachusetts for this species, which is

influenced by winter temperatures. Hadley also

predicts gains but along a much narrower band

from central Illinois to southern Pennsylvania.

Both scenarios predict losses in abundance in the

northwestern portion of the study area due to

projected losses of eastern white pine (Iverson

et al. 1999a).
GTR NE-318~ Atlas of Climate Change Effects in 150 Bird Species of the Eastern United States 325

Red-headed Woodpecker

(Melanerpes erythrocephalus)

Map section page 100

The distribution of this species corresponds

to that of red maple, the most abundant tree

species in the East (Iverson et al. 1999a).

Both CCC and Hadley project increases in

abundance of the woodpecker throughout

the eastern areas from Virginia to Maine, and

in northern Minnesota, Wisconsin, and

North Dakota. Hadley projects an increase

in population along the southern Atlantic

States. The shift in seasonality predicted by

CCC accounts for projected population

decreases in Kansas, Missouri, Illinois, and

Indiana.

Red-bellied Woodpecker

(Melanerpes carolinus)

Map section page 102

For this temperature-sensitive species, both

CCC and Hadley predict increases in

abundance in the northern portion of its range

and in the Appalachian Mountains at higher

elevations. Our model slightly overestimated

the current range of the woodpecker into New

England and northern Minnesota.

Chuck-will's Widow

(Caprimulgus carolinenis)

Map section page 104

This species, which is dominated by average

temperature, is predicted to expand

northward to the Great Lakes by CCC and to

slightly below this northern limit by Hadley.

The two scenarios differ substantially with

respect to affected counties (see histogram).

Whip-poor-will

(Caprimulgus vociferus)

Map section page 106

The distribution of this species is patchy in

the Eastern United States, causing our model

to smooth estimates of abundance, which is

influenced by the abundance of white oak

and annual temperature. Both CCC and

Hadley project the range of the whip-poorwill to expand northward, though a decrease

in overall abundance also is projected.

Common Nighthawk

(Chordeiles minor)

Map section page 108

Our model overgeneralized the range and

abundance of this species in the East in part

because the BBS census protocol is poorly

adapted to mapping species that are active at

dusk and during the night. Both CCC and

Hadley project a dramatic decrease in

abundance for the nighthawk, which is

dominated by winter temperatures. This

major change in abundance is related to a

predicted change in potential

evaportranspiration in the northwestern

portion of the study area.

Chimney Swift

(Chaetura pelagica)

Map section page 110

Little change in abundance is predicted for

this species, which is associated with

precipitation. The larger increases projected

in Michigan, northern Wisconsin,

Minnesota, and the Dakotas are likely to be

offset by numerous smaller decreases over the

entire range within the Eastern United

States.

Ruby-throated Hummingbird

(Archilochus colubris)

Map section page 112

This species is dominated by the abundance

of black tupelo, which is projected to expand

to the north and west. Both CCC and

Hadley predict population gains in the

Midwest and losses in the South, but differ

with respect to the counties affected (see

histogram).

Scissor-tailed Flycatcher

(Tyrannus forficatus)

Map section page 114

This southern species shows one of the largest

relative increases in range and abundance

among the birds examined due to its strong

dependence on summer temperatures and

precipitation. These increases are facilitated by

the projected expansion of Osage-orange

northward from Kansas to Minnesota and

North Dakota. CCC projects a more northerly

expansion than Hadley.
326 GTR NE-318 ~ Atlas of Climate Change Effects in150 Bird Species of the Eastern United States

Eastern Kingbird

(Tyrannus tyrannus)

Map section page 116

This species is associated with red maple and

hickories, and with precipitation, January

temperatures, and seasonality. Within the

study area, CCC predicts a decrease in

abundance in much of the southeast but

increases in the northeast and northwest.

Hadley projects only local decreases.

Eastern Phoebe

(Sayornis phoebe)

Map section page 118

This species, with its unusually patchy

distribution across the study area, is influenced

by seasonality, summer temperatures, and

elevation. Both CCC and Hadley project a

shift in the phoebe's eastern population to the

north and northwest.

Eastern Wood-Pewee

(Contopus virens)

Map section page 120

Both CCC and Hadley project an increase in

abundance over much of the study area. The

latter predicts greater gains in the Piedmont

region of the Carolinas and Virginia because of

our model's dependence on precipitation.

Acadian Flycatcher

(Empidonax virescens)

Map section page 122

Both CCC and Hadley project a northward

shift in the distribution of the population core

of this species, primarily because of its strong

association with January temperatures.

However, because this bird occupies the Eastern

United States only during the summer months,

this temperature association is indirect.

Examples of indirect effects include competition

from species directly limited by winter

temperatures and food limitation due to the

effect of winter conditions on the eggs or pupae

of insects that the Acadian flycatcher later feeds on.

Willow Flycatcher

(Empidonax traillii)

Map section page 124

Both CCC and Hadley project a considerable

retreat northward in the range of this species,

which is influenced indirectly by winter

temperatures. Because the willow flycatcher

occupies the Eastern United States only during

the summer (breeding months), this temperature

association is indirect in that it relates to the

composition of the resident bird community

and/or the availability of insects for food.

Least Flycatcher

(Empidonax minimus)

Map section page 126

Because this species shows a strong association

with the distribution of paper birch, the near

extirpation of which in the Eastern United

States is projected, both CCC and Hadley

predict a marked decrease in the abundance of

the least flycatcher, with only a remnant

population in New Hampshire and

northwestern Maine.

Horned Lark

(Eremophila alpestris)

Map section page 128

Both CCC and Hadley project a patchy

reduction in the abundance of this species in

the Eastern United States, with the greatest

losses along the eastern edge of its range. The

horned lark's association with hickories in our

model may be indirect, e.g., with hickory

species indexing the nearby presence of the

open areas typically favored by this bird.

Blue Jay

(Cyanocitta cristata)

Map section page 130

Both CCC and Hadley predict a decrease in

abundance throughout the Eastern United

States for this species, which is associated with

projected changes in the abundance of red

maple as well as seasonality and summer

temperatures. The histogram reveals

considerable local (county by county)

differences between the two climate scenarios.

American Crow

(Corvus brachyrhynchos)

Map section page 132

Both CCC and Hadley project a decrease in

the abundance throughout the range of this

species, which is associated with July

temperatures and red maple.
GTR NE-318~ Atlas of Climate Change Effects in 150 Bird Species of the Eastern United States 327

Fish Crow

(Corvus ossifragus)

Map section page 134

Both CCC and Hadley project an increase in

abundance and range for this species, which

is associated with winter temperatures. Our

model slightly overestimated the range of the

fish crow, but this output had little effect on

our estimates of change.

European Starling

(Sturnus vulgaris)

Map section page 136

Little change is predicted for the European

starling, which is the most ubiquitous bird

species in our analysis.

Bobolink

(Dolichonyx oryzivorus)

Map section page 138

Both CCC and Hadley project a dramatic

contraction northward in the range of this

northern breeding species, which is

dominated by winter temperatures. Both

scenarios also predict a corresponding

decrease in abundance across the Eastern

United States.

Brown-headed Cowbird

(Molothrus ater)

Map section page 140

Little change is projected by CCC and

Hadley for this ubiquitous species. Losses in

abundance are predicted along the Gulf

States due to changes in winter temperatures,

and along the Atlantic Coast in association

with an increase in the abundance of slash

pine (Iverson et al. 1999a). Both scenarios

project minor population increases in Maine,

Michigan's Upper Peninsula, and

northeastern Minnesota.

Yellow-headed Blackbird

(Xanthocephalus xanthocephalus)

Map section page 142

Our model is representative only with respect

to the eastern edge of the range of this largely

western species, which has a strong

relationship with seasonality. Both CCC and

Hadley predict a northward contraction in

range, with only a remnant population along

the border of North Dakota and Minnesota

(CCC). These projections are largely

peripheral with respect to possible changes in

the range of the yellow-headed blackbird in

the Western United States.

Eastern Meadowlark

(Sturnella magna)

Map section page 144

This species model is strongly associated with

annual precipitation and to lesser extent with

temperature and elevation. Both CCC and

Hadley project an increase in abundance to

the east and northwest, with minor decreases

in Maine and Minnesota (Hadley).

Orchard Oriole

(Icterus spurius)

Map section page 146

For this species, which is dominated by

average yearly temperature, CCC projects a

substantial increase in abundance but losses

in Georgia, South Carolina, and northern

Florida that correspond to a decrease in

precipitation. The slight overgeneralization

by the model of the contemporary range had

little effect on these projections. Some local

increases projected in central Florida result

from the increase in seasonality projected

there, though underlying habitat conditions

may nullify this increase.

Baltimore Oriole

(Icterus galbula)

Map section page 148

Both CCC and Hadley project considerable

losses in abundance with only isolated

increases in range for this species, which is

influenced by minimum temperature. The

model's overgeneralization of contemporary

range had little effect on our estimates of

change.

Brewer's Blackbird

(Euphagus cyanocephalus)

Map section page 150

Extirpation from the Eastern United States

except for counties in northern Minnesota

(Hadley) is projected for this largely western

species, which is dominated by January

temperatures.
328 GTR NE-318 ~ Atlas of Climate Change Effects in150 Bird Species of the Eastern United States

Evening Grosbeak

(Coccothraustes vespertinus)

Map section page 152

Near extirpation is projected for this northern

species, which currently is common only in the

states bordering Canada. Balsam fir, a major

food source for the evening grosbeak,

dominated our model; this bird is projected to

follow the retreat of fir into Canada.

Purple Finch

(Carpodacus purpureus)

Map section page 154

Both CCC and Hadley project a considerable

contraction in range northward and a

substantial loss in abundance throughout the

Eastern United States for this species, which is

associated with the predicted near or total

extirpation of balsam fir. The persistence of the

purple finch in much of New England and the

northern portions of Minnesota, Wisconsin,

and Michigan corresponds to the persistence of

eastern hemlock in those areas.

House Finch

(Carpodacus mexicanus)

Map section page 156

Both CCC and Hadley project losses in

abundance throughout much of the range of

this species, which is influenced by sweet birch,

sourwood, and black cherry. Because the

concentration of the house finch in the

Northeast reflects its release in New York

during the 1940s, it might not yet be in

equilibrium with its environment. As a result,

our model could change over time due to

factors that are unrelated to climate change.

American Goldfinch

(Carduelis tristis)

Map section page 158

Because the distribution of this species is

shaped primarily by climate variables,

particularly average summer temperature, both

CCC and Hadley project extensive losses in

abundance across the range of the American

goldfinch. The loss in abundance is greater

under CCC than Hadley.

Vesper Sparrow

(Pooecetes gramineus)

Map section page 160

Both the CCC and Hadley scenarios project

substantial losses in sparrow abundance and a

northern contraction in range, which is

dominated by January temperatures.

Savannah Sparrow

(Passerculus sandwichensis)

Map section page 162

Both CCC and Hadley project substantial

decreases in the abundance and range

(northward) of this species, which is dominated

by average yearly temperature. The contraction

in range is greater under CCC than Hadley.

Grasshopper Sparrow

(Ammodranus savannarum)

Map section page 164

Both CCC and Hadley project decreases in the

abundance and range of the grasshopper

sparrow. Since the major predictors in its

model (elevation and the range of red maple)

are not anticipated to change under the two

climate scenarios, the shifts in our model

depend on the abundance of Virginia pine and

drought sensitivity in July and August.

White-throated Sparrow

(Zonotrichia albicollis)

Map section page 166

The contraction in range northward projected

for this species corresponds to the predicted

near or total extirpation of balsam fir in the

Eastern United States. Hadley predicts

remnant populations of the sparrow in Maine,

Vermont, New Hampshire, and portions of

New York and Minnesota due to the

persistence of balsam fir and eastern hemlock in

those areas.

Chipping Sparrow

(Spizella passerina)

Map section page 168

Both CCC and Hadley project widespread

losses in the abundance over the entire range of

this species, with only minor local increases.

Much of this predicted loss is linked to

projected losses of northern red oak, though

changes in potential evapotranspiration and

summer temperatures are contributing factors.
GTR NE-318~ Atlas of Climate Change Effects in 150 Bird Species of the Eastern United States 329

Clay-colored Sparrow

(Spizella pallida)

Map section page 170

Both CCC and Hadley project a substantial

contraction in range and a decrease in

abundance for this temperature-sensitive

species. CCC predicts total extirpation while

Hadley projects remnant populations in

several northern counties of Minnesota.

Field Sparrow

(Spizella pusilla)

Map section page 172

Projected increases in abundance in the

Northern States result from shifts in the

distribution of balsam fir and warmer winter

temperatures. In the South, predicted

decreases in abundance correspond to shifts

in the distribution of northern red oak

(CCC) and changes in climate (Hadley).

Dark-eyed Junco

(Junco hyemalis)

Map section page 174

Both CCC and Hadley project substantial

decreases in conjunction with predicted

losses of striped maple. Both scenarios also

project major refuges in the Appalachians at

higher elevations; Hadley also projects

additional populations in Maine and

Minnesota.

Bachman's Sparrow

(Aimophila aestivalis)

Map section page 176

Both CCC and Hadley project increases in

range and abundance for this southern species.

Expansion northward is associated with the

future distribution of slash pine as well as

increases in average annual temperature. The

only predicted decrease in abundance is

associated with changes in summer drought in

Florida.

Song Sparrow

(Melospiza melodia)

Map section page 178

Both CCC and Hadley predict a contraction in

range northward and a decrease in abundance

due to warming conditions. Abundance will

remain high only in the Appalachians, where

the persistence of chestnut oak, which is favored

by the song sparrow, is projected.

Lincoln's Sparrow

(Melospiza lincolnii)

Map section page 180

Near (Hadley) or total (CCC) extirpation is

projected for this northern species in the

Eastern United States. Our model is

dominated by balsam fir and Lincoln's

sparrow is projected to follow the retreat of

fir into Canada.

Swamp Sparrow

(Melospiza georgiana)

Map section page 182

This species model is closely associated with

quaking aspen, for which substantial losses

are projected. CCC predicts a contraction in

range nearly to the Canadian border, while

Hadley projects continued persistence

throughout much of New England, western

New York, Wisconsin, North Dakota,

Minnesota, and northern Michigan.

Eastern Towhee

(Pipilo erythrophthalmus)

Maps section page 184

This species is projected to decrease in

abundance across the Eastern United States

in association with a corresponding loss of

yellow-popular and changes in annual

precipitation and seasonality. Projected

population increases in Iowa, southern

Wisconsin, Illinois Missouri, Nebraska, and

Kansas are associated with predicted local

increases in yellow-poplar.

Northern Cardinal

(Cardinalis cardinalis)

Map section page 186

Projected increases in temperature by CCC

and Hadley allow for potential increases in

abundance in the northern areas for this

species, which is strongly influenced by low

winter temperatures.

Rose-breasted Grosbeak

(Pheucticus ludovicianus)

Map section page 188

Decreases in abundance and a contraction in

range northward are projected for this

species. These changes are dominated by

winter temperatures, and also are linked to

the predicted decrease in the abundance of

quaking aspen.
330 GTR NE-318 ~ Atlas of Climate Change Effects in150 Bird Species of the Eastern United States

Blue Grosbeak

(Guiraca caerulea)

Map section page 190

Both CCC and Hadley project a dramatic

expansion in range northward that is driven by

predicted increases in yearly temperature and

potential evapotranspiration. Also predicted is

a substantial population increase in association

with projected increases in cherrybark oak and

loblolly pine.

Indigo Bunting

(Passerina cyanea)

Map section page 192

A predicted decrease in abundance is the South

corresponds to projected increases in yearly

temperature, with the indigo bunting confined

to a narrow band from South Carolina through

the southern portions of Georgia, Alabama,

Mississippi, and Louisiana (Hadley). CCC

projects continued persistence in Oklahoma

south to the Gulf Coast. Because this species is

also closely associated with precipitation, Hadley

projects a minor overall increase in abundance due

to significant increases in precipitation in the

northwestern portion of the study area.

Painted Bunting

(Passerina ciris)

Map section page 194

This species changes habitats regionally, though

often concentrated in scrub and shrub

environments not quantified within our model.

This may be why our model slightly

overgeneralizes the distribution of the bunting

to include Mississippi, Alabama, and Georgia.

Because this species model is dominated by

summer temperatures, Hadley projects an

increase in abundance within its current range,

with expansion into Maryland and southern

Nebraska. CCC projects an expansion

northward into South Dakota and much of

Illinois and Indiana.

Dickcissel

(Spiza americana)

Map section page 196

An expansion in range is projected for this

species, particularly by CCC. Because this is

primarily a grassland and cropland species and

the northern edge of its range has been linked

with sorghum planting (unpublished data), the

ability of the dickcissel to expand into heavily

forested eastern counties might be restricted.

Summer Tanager

(Piranga rubra)

Map section page 198

Increases in abundance and range northward

are projected for this southern species, which is

dominated by winter temperatures even though

the summer tanager occupies the Eastern

United States only during the summer

(breeding) months. This suggests that this

temperature association is indirect.

Purple Martin

(Progne subis)

Map section page 200

This species has a complex distribution, with

areas of locally high and low abundance

throughout much of the Eastern United States.

As a result, our model overgeneralized

abundance. Both CCC and Hadley project an

increase in abundance, which is linked to the

distribution of sweetgum (Iverson et al. 1999a).

Cliff Swallow

(Petrochelidon pyrrhonota)

Map section page 202

Both CCC and Hadley project a contraction in

range northward for this species, which is

influenced by several climate variables,

particularly winter temperatures.

Barn Swallow

(Hirundo rustica)

Map section page 204

Both CCC and Hadley predict only slight

decreases in the abundance of this ubiquitous

species, which is influenced by winter

temperatures. Decreases are projected from

South Carolina west to Texas and eastern

Oklahoma.

Tree Swallow

(Tachycineta bicolor)

Map section page 206

Our model shows a strong correlation with the

distribution of quaking aspen. CCC projects a

contraction in range northward to North

Dakota, the northern portions of Minnesota

and Wisconsin, Michigan's Upper Peninsula,

and northern New England. The predicted

retreat of the tree swallow is less severe under

Hadley. Our model failed to capture small

populations of this species in Arkansas,

Kentucky, southern Illinois, and Indiana.
GTR NE-318~ Atlas of Climate Change Effects in 150 Bird Species of the Eastern United States 331

Bank Swallow

(Riparia riparia)

Map section page 208

Both CCC and Hadley project a significant

decrease in the abundance of this species, which

is sensitive to annual temperature. CCC

predicts greater contraction in range northward

than Hadley. Although our model reasonably

depicts the current range, it overgeneralized the

patchy nature of the current distribution of the

bank swallow.

Cedar Waxwing

(Bombycilla cedrorum)

Map section page 210

Both CCC and Hadley project a substantial

decrease in the range and population of this

species across the Eastern United States. These

decreases are associated with the projected shifts

of potential evapotranspiration (the dominant

variable in our model).

Loggerhead Shrike

(Lanius ludovicianus)

Map section page 212

Both CCC and Hadley project an increase in

the abundance (greater under CCC)

throughout the study area for this species,

which is strongly influenced by shifts in July

temperatures.

Red-eyed Vireo

(Vireo olivaceus)

Map section page 214

The slight decrease in abundance projected for

this species by CCC and Hadley corresponds to

the predicted reduction of red maple

abundance over much of its current range.

Warbling Vireo

(Vireo gilvus)

Map section page 216

Although our model predicted well the species

range, it does not capture the patchy

distribution of the warbling vireo. Both CCC

and Hadley project a decrease in the

abundance of this species. CCC projects a

contraction in range northward while Hadley

predicts range expansion, primarily in

southern Virginia, North Carolina, and

Tennessee. These shifts are linked to

projected shifts in seasonality.

Yellow-throated Vireo

(Vireo flavifrons)

Map section page 218

Slight increases in abundances primarily in

the northern areas projected for this species

coincide with a predicted northward shift in

the distribution of yellow-poplar. Our model

cannot capture the considerable variation in

this species' contemporary distribution, so it

should be viewed as a rough model of species

distribution.

Blue-headed Vireo

(Vireo solitarius)

Map section page 220

The significant contraction in range projected

for the blue-headed vireo is expected to follow

the predicted retreat of striped maple and

balsam fir in the eastern and western portion

of its range. The predicted persistence of this

species in parts of the Appalachians is related

to its sensitivity to elevation.

White-eyed Vireo

(Vireo griseus)

Map section page 222

CCC projects an increase in range throughout

the study area and an increase in abundance

throughout the northern portion of the range

of this species. Hadley projects range

expansion into South Dakota, northern

Illinois, Michigan, and western New York in

conjunction with changes in winter

temperatures.

Black-and-white Warbler

(Mniotilta varia)

Map section page 224

Decreases in abundance along the Canadian

border and increases elsewhere are associated

with a projected decrease in balsam fir and

increase in blackgum, respectively. Predicted

high populations of this species also are

related to the presence of eastern hemlock,

indicating a net increase in abundance and

range for the black-and-white warbler.
332 GTR NE-318 ~ Atlas of Climate Change Effects in150 Bird Species of the Eastern United States

Prothonotary Warbler

(Protonotaria citrea)

Map section page 226

Both CCC and Hadley project a substantial

increase in range northward in response to

predicted increases in abundance of water oak

and winged elm, both of which are found in

the bottomland hardwood forests inhabited

by the prothonotary warbler. However, an

overall decrease in population is projected

due to the loss of this species across its

southern range.

Worm-eating Warbler

(Helmitheros vermivorus)

Map section page 228

Although the worm-eating warbler is closely

associated with the presence of chestnut oak

in the Appalachians, CCC projects a decrease

in abundance there associated with projected

increases in temperature and changes in

seasonality. Our model overgeneralized some

regional variation in bird density to infer a

link with blackgum. We suspect that local

factors involving predictors not included in

our analysis shape the details of much of the

low-density portions of the range of this

species. However, these density factors have

little effect on our estimates of the future

distribution of this bird.

Blue-winged Warbler

(Vermivora pinus)

Map section page 230

The projected contraction northward and

decrease in abundance throughout the range

of this species parallels the predicted loss of

sassafras and changes in potential

evapotranspiration. Severe population losses

of the blue-winged warbler are predicted in

West Virginia, Ohio, and Kentucky, where it

currently is the most abundant.

Golden-winged Warbler

(Vermivora chrysoptera)

Map section page 232

Both CCC and Hadley project a contraction

in range northward or into the Appalachians

at higher elevations in response to predicted

major losses of yellow birch and quaking

aspen. CCC projects total loss of this species

from the western areas within the study area.

Nashville Warbler

(Vermivora ruficapilla)

Map section page 234

CCC projects the total extirpation of this species

in the Eastern United States in association with

the corresponding predicted near extirpation of

balsam fir and shifts in summer temperature.

Hadley projects the withdrawal of the Nashville

warbler from the southern portion of its range.

Northern Parula

(Parula americana)

Map section page 236

Predicted dramatic losses of this species in the

Northern States in connection with predicted

losses of balsam fir are expected to be partially

offset by population increases along a broad

band from Nebraska to Kansas east to Maryland

and north along the Massachusetts coast. These

increases correspond to predicted increases in

the abundance of common persimmon as well as

climate changes in the extreme southern portion

of the range of this bird.

Yellow Warbler

(Dendroica petechia)

Map section page 238

Both CCC and Hadley project a decrease in

abundance and in range northward for this

species, which is influenced by July temperatures.

Black-throated Blue Warbler

(Dendroica caerulescens)

Map section page 240

CCC and Hadley each projects both a

contraction in range and a decrease in the

abundance of this species in Virginia and North

Carolina at higher elevations and northward to

northwestern New England. These changes are

associated with projected substantial decreases in

the abundance of striped maple and yellow

birch in the study area.

Yellow-rumped Warbler

(Dendroica coronata)

Map section page 242

CCC predicts the total extirpation of this species

from the Eastern United States in conjunction

with a similar prediction for balsam fir. Hadley

projects the persistence of small populations in

northwestern New England and in northeastern

Minnesota.
GTR NE-318~ Atlas of Climate Change Effects in 150 Bird Species of the Eastern United States 333

Magnolia Warbler

(Dendroica magnolia)

Map section page 244

A significant decrease in the abundance of this

northern species throughout its current range is

projected in association with the predicted near

extirpation of balsam fir. However, the

persistence of small populations of the magnolia

warbler in the Eastern United States is

projected in response to suitable climate and

elevation and the presence of yellow birch.

Cerulean Warbler

(Dendroica cerulea)

Map section page 246

Both CCC and Hadley project a decrease in

abundance and a shift in range northward in

association with similar predictions for both

sassafras and sourwood. These tree species were

dominant in our model and are common where

the cerulean warbler is most abundant.

Blackburnian Warbler

(Dendroica fusca)

Map section page 248

For this species, which is dominated by July

temperatures, CCC projects total extirpation

from the study area, while Hadley allows a

remnant population in northwestern New

England and in several counties in Minnesota.

These predictions are associated with projected

decreases in balsam fir and striped maple.

Yellow-throated Warbler

(Dendroica dominica)

Map section page 250

The predicted decrease in abundance in the

southeastern portion of the range of this species

is driven largely by projected shifts in winter

temperatures and in potential evapotranspiration.

Evidence of overgeneralization within the model

might negate the apparent additional influence

of yellow-poplar, pignut hickory, and swamp

tupelo.

Black-throated Green Warbler

(Dendroica virens)

Map section page 252

Substantial decreases in abundance and

contraction in range predicted for this species

are associated with predicted losses of balsam fir,

striped maple, and yellow birch resulting from

climate change.

Pine Warbler

(Dendroica pinus)

Map section page 254

Although this species is dominated by the

abundance of loblolly pine, there are disjunct

populations along the Canadian border that are

associated with balsam fir. The loss of these

northern populations projected by CCC likely

will be offset by predicted gains in the South.

Hadley predicts more widespread decreases in

abundance and a substantial net population

loss.

Prairie Warbler

(Dendroica discolor)

Map section page 256

The expansion in range northward projected for

this species is related to the presence of

blackgum and sourwood. A decrease in the

abundance of the prairie warbler in the

Southeast is associated with predicted changes

in precipitation patterns.

Ovenbird

(Seiurus aurocapillus)

Map section page 258

Both CCC and Hadley project a substantial

decrease in abundance and a contraction in

range northward for this species. In the

southern portion of its range, the ovenbird is

expected to retreat into the Appalachians. Our

model, which is dominated by annual

temperatures and the abundance of red maple

and eastern white pine, projects that substantial

numbers of this species will persist in the

northern areas where an increase in white pine

is predicted.

Northern Waterthrush

(Seiurus noveboracensis)

Map section page 260

Both CCC and Hadley project a decrease in

abundance and contraction in range northward

in association with the predicted loss of balsam

fir. However, CCC projects remnant

populations in northwestern New England and

several counties in New York due to the

presence of yellow birch, while Hadley predicts

the persistence of the northern waterthrush in

several additional counties in New England and

Michigan, Wisconsin, and northern Minnesota.
334 GTR NE-318 ~ Atlas of Climate Change Effects in150 Bird Species of the Eastern United States

Kentucky Warbler

(Oporornis formosus)

Map section page 262

Both Hadley and CCC project an increase in

abundance and expansion in range northward

resulting from changes in winter temperatures.

Also predicted is a decrease in abundance in the

southern portion of the range of the Kentucky

warbler due to a predicted shift northward in

the distribution of white ash.

Mourning Warbler

(Oporornis philadelphia)

Map section page 264

CCC projects the total extirpation of this

species in conjunction with a similar prediction

for northern white-cedar. Hadley predicts the

persistence of the mourning warbler in portions

of Minnesota and Michigan and in the

northwestern New England in association with

projected changes in summer temperatures and

precipitation.

Common Yellowthroat

(Geothlypis trichas)

Map section page 266

A substantial decrease in abundance within its

current range is predicted for the common

yellowthroat, largely in response to projected

shifts in potential evapotranspiration.

Yellow-breasted Chat

(Icteria virens)

Map section page 268

The projected expansion in the range of this

species throughout New England and west into

Minnesota and South Dakota is expected to be

offset largely by a predicted decrease in

abundance along the Gulf Coast and southern

Atlantic States due to higher winter temperatures.

Hooded Warbler

(Wilsonia citrina)

Map section page 270

CCC projects an increase in abundance and

an expansion in range northward into

Wisconsin, the central counties of Michigan,

and along coastal Maine. Both CCC and

Hadley project a decrease in abundance along

the Appalachians and Gulf and Atlantic

Coasts. Seasonality is the dominant

predictor in our model and drives much of

the projected changes for this species.

Canada Warbler

(Wilsonia canadensis)

Map section page 272

Projected substantial decreases in the

abundance and range of this species by CCC

and Hadley are closely associated with

predicted losses of balsam fir, striped maple,

and yellow birch.

American Redstart

(Setophaga ruticilla)

Map section page 274

A decrease in abundance in the northern

portion of its range, particularly in Michigan,

Wisconsin, and Minnesota, is predicted for

this species. However, these losses likely will

be offset by a projected increase in

abundance and expansion in range from

Illinois west to eastern Nebraska and Kansas.

These shifts are predominantly in

conjunction with predicted changes in

average July and yearly temperatures.

House Sparrow

(Passer domesticus)

Map section page 276

This ubiquitous, exotic species, which was

introduced to the United States during the

19th century, is strongly associated with

urban areas and agricultural lands. Both

CCC and Hadley project only a slight

increase in abundance in the Northern States

resulting from predicted climate change.

Northern Mockingbird

(Mimus polyglottos)

Map section page 278

An increase in abundance throughout the

northern third of the study area is predicted for

this species, which is dominated by January

temperatures. Our model overgeneralized the

current range of the mockingbird into

Wisconsin, Minnesota, and the Dakotas.

Gray Catbird

(Dumetella carolinensis)

Map section page 280

Decreases in abundance in the central portion

of the study area along with additional losses to

the north (CCC) and in the southern Atlantic

States (Hadley) are predicted for this species,

which is dominated by July temperatures.
GTR NE-318~ Atlas of Climate Change Effects in 150 Bird Species of the Eastern United States 335

Brown Thrasher

(Toxostoma rufum)

Map section page 282

This species is commonly associated with

regenerating forests and is scarce in heavily

forested areas. The dominance of eastern

hemlock, a shade-tolerant species, in our model

serves as an indicator of heavily forested areas.

The northward population shift projected for

the brown thrasher is driven by expected shifts

in both the abundance of eastern hemlock and

July temperatures.

Carolina Wren

(Thryothorus ludovicianus)

Map section page 284

Both CCC and Hadley project an increase in

abundance and expansion in range northward

for this species, which is dominated by winter

temperatures.

House Wren

(Troglodytes aedon)

Map section page 286

Both CCC and Hadley project a decrease in

abundance and contraction in range northward,

resulting from a predicted increase in winter

temperatures. Both scenarios project a band

(wide under CCC vs. narrow under Hadley) of

losses from Kansas to western North Carolina

and north along coastal New England.

Winter Wren

(Troglodytes troglodytes)

Map section page 288

A decrease in abundance and contraction in

range are predicted for this species. The

winter wren is associated with older

coniferous forests, and our model may be

capturing this association by the dominance

of balsam fir in the species model. Both CCC

and Hadley project remnant populations

(slightly higher under Hadley) in western

Maine, northern Vermont, New Hampshire,

and New York.

Sedge Wren

(Cistothorus platensis)

Map section page 290

Both CCC and Hadley project a decrease in

abundance and contraction in range for this

species, which is dominated by January

temperatures. CCC predicts a more severe

contraction, with low populations persisting

in Minnesota, southern Wisconsin, and

Michigan. Our model slightly

overgeneralized the range of the sedge wren

into northwestern New England.

Brown Creeper

(Certhia americana)

Map section page 292

This species feeds on insects and forages

directly on the trunks of numerous tree

species for which decreases in abundance are

predicted. As a result, both CCC and Hadley

project a decrease in the abundance of the

brown creeper, with remnant populations in

New England, New York, Pennsylvania,

Michigan, Wisconsin, and Minnesota.

White-breasted Nuthatch

(Sitta carolinensis)

Map section page 294

Both CCC and Hadley project an increase in

abundance and expansion in range southward

for this species in response to projected changes

in late-summer temperatures. This cavitynesting species forages directly on tree trunks

and is closely associated with mature forests,

particularly those dominated by northern red oak.

Red-breasted Nuthatch

(Sitta canadensis)

Map section page 296

The predicted decrease in the abundance of this

species is linked to the predicted loss of balsam

fir. CCC projects remnant populations only in

northwestern New England; Hadley predicts

the persistence of the red-breasted nuthatch

across the northern portion of the study area.

Brown-headed Nuthatch

(Sitta pusilla)

Map section page 298

Both CCC and Hadley project a decrease in the

abundance of this species in east Texas,

Louisiana, Arkansas, and along the southeastern

Atlantic Coast, resulting in a net loss in

population under Hadley. CCC predicts an

expansion in range northward to Kansas and

Delaware in response to the projected increase

in winter temperatures.
336 GTR NE-318 ~ Atlas of Climate Change Effects in150 Bird Species of the Eastern United States

Tufted Titmouse

(Baeolophus bicolor)

Map section page 300

Both CCC and Hadley project an increase in

abundance (particularly to the north) within

the current range of this species. In our model,

January temperature is the dominant predictor.

Black-capped Chickadee

(Poecile atricapillus)

Map section page 302

Both CCC and Hadley project a decrease in

abundance and contraction in range northward

in response to the projected shift in January

temperatures and the projected decrease in the

abundance of yellow birch. Although certain

counties in Georgia and Florida appear to be

suitable for this species under the CCC

scenario, the black-capped chickadee is unlikely

to expand into this region due to intense

competition from the Carolina chickadee.

Blue-gray Gnatcatcher

(Polioptila caerulea)

Map section page 304

The predicted increase in the abundance of this

species across the northern areas and its possible

expansion in range northward are linked to

January temperatures and the projected shift

northward in the distribution of flowering

dogwood.

Wood Thrush

(Hylocichla mustelina)

Map section page 306

Our model for this species reflects its breeding

habitat in eastern broadleaf forests, with strong

correlations with red maple, yellow-poplar, and

American beech. Both CCC and Hadley

predict reductions in numbers over its range in

eastern forests, largely paralleling projections for

these tree species by Iverson et al. (1999a).

Veery

(Cathharus fuscescens)

Map section page 308

Both CCC and Hadley project a substantial

decrease in abundance and a contraction in

range for the veery in the Eastern United States.

These losses are in conjunction with the

predicted contraction in the range of eastern

white pine, decrease in abundance of sweet

birch, and climate shifts.

Swainson's Thrush

(Catharus ustulatus)

Map section page 310

CCC predicts the total extirpation of this

predominantly northern species from the

Eastern United States in association with a

similar prediction for balsam fir. Hadley

projects relict populations in northwestern New

England and in one county in Minnesota.

Hermit Thrush

(Catharus guttatus)

Map section page 312

This species breeds in moist forests containing

balsam fir and eastern hemlock. The predicted

decrease in abundance and contraction in range

for the hermit thrush corresponds to similar

losses predicted for those tree species. Both

CCC and Hadley project remnant populations

in New England, Pennsylvania, Michigan,

Wisconsin, and Minnesota.

American Robin

(Turdus migratorius)

Map section page 314

The breeding distribution of this species is

strongly associated with January temperatures

and weakly correlated with summer

temperatures. As a result, the range of the

American robin is projected to expand

southward, with populations reaching the Gulf

Coast as far east as the panhandle of Florida.

However, some local decreases within the

southern portion of its current range also are

predicted in response to expected changes in

seasonality.
GTR NE-318~ Atlas of Climate Change Effects in 150 Bird Species of the Eastern United States 337

Map section Species interpretation

Bird species page number page number

Bittern, American (Botaurus lentiginosus) 32 321

Blackbird

Brewer's (Euphagus cyanocephalus) 150 327

Yellow-headed (Xanthocephalus xanthocephalus) 142 327

Bobolink, (Dolichonyx oryzivorus) 138 327

Bobwhite, Northern (Colinus virginianus) 60 322

Bunting

Indigo (Passerina cyanea) 192 330

Painted (Passerina ciris) 194 330

Cardinal, Northern (Cardinalis cardinalis) 186 329

Catbird, Gray (Dumetella carolinensis) 280 334

Chat, Yellow-breasted (Icteria virens) 268 334

Chickadee, Black-capped (Poecile atricapillus) 302 336

Chuck-Will's Widow (Caprimulgus carolinenis) 104 325

Coot, American (Fulica americana) 50 322

Cowbird, Brown-headed (Molothrus ater) 140 327

Creeper, Brown (Certhia americana) 292 335

Crow

American (Corvus brachyrhynchos) 132 326

Fish (Corvus ossifragus) 134 327

Cuckoo

Black-billed (Coccyzus erythropthalmus) 92 324

Yellow-billed (Coccyzus americanus) 90 324

Dickcissel (Spiza americana) 196 330

Dove

Common Ground (Columbina passerina) 70 323

Mourning (Zenaida macroura) 68 323

Rock (Columba livia) 66 322

Egret

Cattle (Bubulcus ibis) 42 321

Great (Ardea alba) 36 321

Snowy (Egretta thula) 38 321

Finch

House (Carpodacus mexicanus) 156 328

Purple (Carpodacus purpureus) 154 328

Flycatcher

Acadian (Empidonax virescens) 122 326

Least (Empidonax minimus) 126 326

Scissor-tailed (Tyrannus forficatus) 114 325

Willow (Empidonax traillii) 124 326

Gnatcatcher, Blue-gray (Polioptila caerulea) 304 336

Goldfinch, American (Carduelis tristis) 158 328

Goose, Canada (Branta canadensis) 28 320

Grosbeak

Blue (Guiraca caerulea) 190 330

Evening (Coccothraustes vespertinus) 152 328

Rose-breasted (Pheucticus ludovicianus) 188 329

Grouse, Ruffed (Bonasa umbellus) 62 322

Gull

Laughing (Larus atricilla) 20 320

Ring-billed (Larus delawarensis) 18 320

Harrier, Northern (Circus cyaneus) 78 323

Index of Bird Species
338 GTR NE-318 ~ Atlas of Climate Change Effects in150 Bird Species of the Eastern United States

Map section Species interpretation

Bird species page number page number

Hawk

Broad-winged (Buteo platypterus) 84 324

Red-shouldered (Buteo lineatus) 82 323

Red-tailed (Buteo jamaicensis) 80 323

Heron

Great Blue (Ardea herodias) 34 321

Green (Butorides virescens) 44 321

Little Blue (Egretta caerulea) 40 321

Yellow-crowned Night (Nyctanassa violacea) 46 321

Hummingbird, Ruby-throated (Archilochus colubris) 112 325

Ibis, White (Eudocimus albus) 30 320

Jay, Blue (Cyanocitta cristata) 130 326

Junco, Dark-eyed (Junco hyemalis) 174 329

Kestrel, American (Falco sparverius) 86 324

Killdeer (Charadrius vociferus) 56 322

Kingbird, Eastern (Tyrannus tyrannus) 116 326

Kite, Mississippi (Ictinia mississippiensis) 76 323

Lark, Horned (Eremophila alpestris) 128 326

Loon, Common (Gavia immer) 16 320

Mallard, (Anas platyrhynchos) 24 320

Martin, Purple (Progne subis) 200 330

Meadowlark, Eastern (Sturnella magna) 144 327

Mockingbird, Northern (Mimus polyglottos) 278 334

Nighthawk, Common (Chordeiles minor) 108 325

Nuthatch

Brown-headed (Sitta pusilla) 298 335

Red-breasted (Sitta canadensis) 296 335

White-breasted (Sitta carolinensis) 294 335

Oriole

Orchard (Icterus spurius) 146 327

Baltimore (Icterus galbula) 148 327

Ovenbird (Seiurus aurocapillus) 258 333

Owl, Great Horned (Bubo virginianus) 88 324

Partridge, Gray (Perdix perdix) 58 322

Parula, Northern (Parula americana) 236 332

Pewee, Eastern Wood (Contopus virens) 120 326

Pheasant, Ring-necked (Phasianus colchicus) 64 322

Phoebe, Eastern (Sayornis phoebe) 118 326

Redstart, American (Setophaga ruticilla) 274 334

Robin, American (Turdus migratorius) 314 336

Sandpiper, Spotted (Actitis macularia) 54 322

Sapsucker, Yellow-bellied (Sphyrapicus varius) 96 324

Shrike, Loggerhead (Lanius ludovicianus) 212 331

Snipe, Common (Gallinago gallinago) 52 322

Sora (Porzana carolina) 48 321

Sparrow

Bachman's (Aimophila aestivalis) 176 329

Chipping (Spizella passerina) 168 328

Clay-colored (Spizella pallida) 170 329

Field (Spizella pusilla) 172 329

Grasshopper (Ammodramus savannarum) 164 328

House (Passer domesticus) 276 334

Lincoln's (Melospiza lincolnii) 180 329
GTR NE-318~ Atlas of Climate Change Effects in 150 Bird Species of the Eastern United States 339

Map section Species interpretation

Bird species page number page number

Sparrow

Savannah (Passerculus sandwichensis) 162 328

Song (Melospiza melodia) 178 329

Swamp (Melospiza georgiana) 182 329

Vesper (Pooecetes gramineus) 160 328

White-throated (Zonotrichia albicollis) 166 328

Starling, European (Sturnus vulgaris) 136 327

Swallow

Bank (Riparia riparia) 208 331

Barn (Hirundo rustica) 204 330

Cliff (Petrochelidon pyrrhonota) 202 330

Tree (Tachycineta bicolor) 206 330

Swift, Chimney (Chaetura pelagica) 110 325

Tanager, Summer (Piranga rubra) 198 330

Teal, Blue-winged (Anas discors) 26 320

Tern, Black (Chlidonias niger) 22 320

Thrasher, Brown (Toxostoma rufum) 282 335

Thrush

Hermit (Catharus guttatus) 312 336

Swainson's (Catharus ustulatus) 310 336

Wood (Hylocichla mustelina) 306 336

Titmouse, Tufted (Baeolophus bicolor) 300 336

Towhee, Eastern (Pipilo erythrophthalmus) 184 329

Veery (Catharus fuscescens) 308 336

Vireo

Blue-headed (Vireo solitarius) 220 331

Red-eyed (Vireo olivaceus) 214 331

Warbling (Vireo gilvus) 216 331

White-eyed (Vireo griseus) 222 331

Yellow-throated (Vireo flavifrons) 218 331

Vulture

Black (Coragyps atratus) 74 323

Turkey (Cathartes aura) 72 323

Warbler

Black-and-white (Mniotilta varia) 224 331

Blackburnian (Dendroica fusca) 248 333

Black-throated Blue (Dendroica caerulescens) 240 332

Black-throated Green (Dendroica virens) 252 333

Blue-winged (Vermivora pinus) 230 332

Canada (Wilsonia canadensis) 272 334

Cerulean (Dendroica cerulea) 246 333

Golden-winged (Vermivora chrysoptera) 232 332

Hooded (Wilsonia citrina) 270 334

Kentucky (Oporornis formosus) 262 334

Magnolia (Dendroica magnolia) 244 333

Mourning (Oporornis philadelphia) 264 334

Nashville (Vermivora ruficapilla) 234 332

Pine (Dendroica pinus) 254 333

Prairie (Dendroica discolor) 256 333

Prothonotary (Protonotaria citrea) 226 332

Worm-eating (Helmitheros vermivorus) 228 332

Yellow (Dendroica petechia) 238 332

Yellow-rumped (Dendroica coronata) 242 332

Yellow-throated (Dendroica dominica) 250 333
340 GTR NE-318 ~ Atlas of Climate Change Effects in150 Bird Species of the Eastern United States

Waterthrush, Northern (Seiurus noveboracensis) 260 333

Waxwing, Cedar (Bombycilla cedrorum) 210 331

Whip-poor-will (Caprimulgus vociferus) 106 325

Woodpecker

Downy (Picoides pubescens) 94 324

Pileated (Dryocopus pileatus) 98 324

Red-bellied (Melanerpes carolinus) 102 325

Red-headed (Melanerpes erythrocephalus) 100 325

Wren

Carolina (Thryothorus ludovicianus) 284 335

House (Troglodytes aedon) 286 335

Sedge (Cistothorus platensis) 290 335

Winter (Troglodytes troglodytes) 288 335

Yellowthroat, Common (Geothlypis trichas) 266 334

Map section Species interpretation

Bird species page number page number
Printed on Recycled Paper

The U. S. Department of Agriculture (USDA) prohibits discrimination in all its programs and

activities on the basis of race, color, national origin, gender, religion, age, disability, political

beliefs, sexual orientation, and marital or family status. (Not all prohibited bases apply to all

programs.) Persons with disabilities who require alternative means for communication of

program information (Braille, large print, audiotape, etc.) should contact the USDA's TARGET

Center at (202)720-2600 (voice and TDD).

To file a complaint of discrimination, write USDA, Director, Office of Civil Rights, Room 326-W,

Whitten Building, 14th and Independence Avenue SW, Washington, DC 20250-9410, or call

(202)720-5964 (voice and TDD). USDA is an equal opportunity provider and employer.

Matthews, Stephen; O'Connor, Raymond; Iverson, Louis R.; Prasad, Anantha M. 2004.

Atlas of climate change effects in 150 bird species of the Eastern United States.

Gen. Tech. Rep. NE-318. Newtown Square, PA: U.S. Department of Agriculture,

Forest Service, Northeastern Research Station. 340 p.

This atlas documents the current and potential future distribution of 150 common bird

species in the Eastern United States. Distribution data for individual species were

derived from the Breeding Bird Survey (BBS) from 1981 to 1990. Regression tree

analysis was used to model the BBS data as functions of contemporary climate and

elevation variables and the current distribution of 68 tree species that occurred in the

bird models. The model for each bird species is described. These models were projected

onto two scenarios of global climate change. Depending on the global climate model

used, as many as 78 bird species are projected to decrease in abundance by at least 25

percent, while as many as 33 species are projected to increase in abundance by at least 25

percent.

Keywords: birds; global climate change; trees; species distributions; range; distribution;

regression tree analysis
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