Section 12.0 Ecological Exposure Factors

12-1

12.0 Ecological Exposure Factors

Ecological exposure factors are used in the Ecological Exposure Module of the 3MRA

modeling system to calculate the total exposure dose (in mg/kg/d) to a suite of receptors that 

consume contaminated media and food items within their respective habitats. The Ecological

Exposure Module calculates exposure doses based on media and food concentration inputs

generated by other modules. The Ecological Exposure Module requires the following inputs:

# Aquatic Food Web Module–Contaminant concentrations in the aquatic food

web.

# Surface Impoundment Module–Contaminant concentrations in surface

impoundment water.

# Surface Water Module–Contaminant concentrations in surface water and

sediment.

# Terrestrial Food Web Module–Contaminant concentrations in the terrestrial

food web (including vegetation, prey items, and soil).

# Ecological Exposure Module–Receptor-specific values for body weight,

ingestion rates, and prey preferences.

# Site Layout Inputs–Site-specific input on habitats, receptors, waterbodies, and

prey present at a site.

The ecological exposure module calculates the exposure dose for 52 terrestrial receptor

species as they occur in any of 11 ecological habitats. Table 12-1 lists the terrestrial wildlife

receptors in the representative national data set. These receptors are representative of mammals,

birds, and reptiles. Section 13.0 provides additional discussion about the selection of receptors

and their respective habitats.

Exposure to the ecological receptors may occur through the following ingestion

pathways:

# Ingestion of soil or sediment

# Ingestion of aquatic and terrestrial vegetation

# Ingestion of aquatic and terrestrial prey items

# Ingestion of surface water.
Section 12.0 Ecological Exposure Factors

12-2

Table 12-1. Exposure Data Sources for Terrestrial Wildlife Receptors

Species Scientific Name References

Alligator snapping turtle Macroclemys temminckii Lane and Mitchell, 1997; Conant and Collins, 1991

American kestrel Falco sparverius Terres, 1980; U.S. EPA, 1993; Lane and Fischer,

1997; Stokes and Stokes, 1996

American robin Turdus migratorius Terres, 1980; U.S. EPA, 1993; Stokes and Stokes,

1996

American woodcock Scolopax minor Terres, 1980; U.S. EPA, 1993; Stokes and Stokes,

1996

Bald eagle Haliaeetus leucocephalus Terres, 1980; U.S. EPA, 1993; Stokes and Stokes,

1996

Beaver Castor canadensis Stokes and Stokes, 1986; Whitaker, 1997; Jenkins

and Busher, 1979

Belted kingfisher Ceryle alcyon Terres, 1980; U.S. EPA, 1993; Stokes and Stokes,

1996

Black bear Ursus americanus Schaefer and Sargent, 1990; Stokes and Stokes,

1986; Whitaker, 1997

Black-tailed jackrabbit Lepus californicus Whitaker, 1997; Sample et al., 1997; MacMahon,

1985

Burrowing owl Speotyto cunicularia Terres, 1980; Sample et al., 1997; Stokes and Stokes,

1996

Canada goose Branta canadensis Terres, 1980; U.S. EPA, 1993; Niering, 1985; Stokes

and Stokes, 1996

Cerulean warbler Dendroica cerulea Evans and Fischer, 1997; Terres, 1980; Stokes and

Stokes, 1996

Cooper's hawk Accipiter cooperi Terres, 1980; Sample et al., 1997; Stokes and Stokes,

1996

Coyote Canis latrans Bekoff, 1977; Sample et al, 1997; Whitaker, 1997; 

Stokes and Stokes, 1986

Deer mouse Peromyscus maniculatus Whitaker, 1997; U.S. EPA, 1993; Stokes and Stokes,

1986

Eastern box turtle Terrapene carolina Martof et al., 1980; U.S. EPA, 1993; Sutton and

Sutton, 1985; Conant and Collins, 1991

Eastern cottontail rabbit Sylvilagus floridanus Stokes and Stokes, 1986; Chapman et al., 1980;

Whitaker, 1997; U.S. EPA, 1993

Great blue heron Ardea herodias Terres, 1980; U.S. EPA, 1993; Stokes and Stokes,

1996; Niering, 1985

Great Basin pocket mouse Perognathus parvus Whitaker, 1997; Sample et al., 1997

Green heron Butorides virescens Terres, 1980; Sample et al., 1997; Stokes and Stokes,

1996; Niering, 1985

Herring gull Larus argentatus Terres, 1980; U.S. EPA, 1993; Stokes and Stokes,

1996

Kit fox Vulpes velox McGrew, 1979; Sample et al., 1997; MacMahon,

1985; Whitaker, 1997

(continued)
Table 12-1. (continued)

Section 12.0 Ecological Exposure Factors

Species Scientific Name References

12-3

Least weasel Mustela nivalis Whitaker, 1997; Stokes and Stokes, 1986; Sample et

al., 1997

Lesser scaup Aythya affinis Terres, 1980; U.S. EPA, 1993; Stokes and Stokes,

1996

Little brown bat Myotis lucifugus Whitaker, 1997; Sample et al., 1997.

Loggerhead shrike Lanius ludovicianus Hall et al., 1997; Terres, 1980; Stokes and Stokes,

1996

Long-tailed weasel Mustela frenata Sutton and Sutton, 1985; Sample et al., 1997; Stokes

and Stokes, 1996

Mallard Anas platyrhynchos Terres, 1980; U.S. EPA, 1993; Stokes and Stokes,

1996; Niering, 1985

Marsh wren Cistothorus palustris Terres, 1980; U.S. EPA, 1993; Stokes and Stokes,

1996; Niering, 1985

Meadow vole Microtus pennsylvanicus Whitaker, 1997; U.S. EPA, 1993; Stokes and Stokes,

1986

Mink Mustela vison Niering, 1985; U.S. EPA, 1993; Whitaker, 1997;

Stokes and Stokes,1986

Mule deer Odocoileus hemionus Whitaker, 1997; Sample et al., 1997; Anderson and

Wallmo, 1984; Whitney, 1985

Muskrat Ondatra zibethicus Niering, 1985; U.S. EPA, 1993; Stokes and Stokes,

1986; Willner et al., 1980; Whitaker, 1997

Northern water snake Nerodia sipedon Martof et al., 1980; U.S. EPA, 1993; Conant and

Collins, 1991; Niering, 1985; Behler and King, 1979 

Northern bobwhite Colinus virginianus Terres, 1980; U.S. EPA, 1993; Stokes and Stokes,

1996

Osprey Pandion haliaetus Terres, 1980; U.S. EPA, 1993; Stokes and Stokes,

1996

Painted turtle Chrysemys picta Niering, 1985; U.S. EPA, 1993; Conant and Collins,

1991; Behler and King, 1979

Pine vole Microtus pinetorum Whitaker, 1997; Sample et al., 1997

Prairie vole Microtus ochrogaster Whitaker, 1997; U.S. EPA, 1993 

Raccoon Procyon lotor Lotze and Andersen, 1979; U.S. EPA, 1993;

Whitaker, 1997; Stokes and Stokes, 1986

Racer Coluber constrictor Behler and King, 1979; U.S. EPA, 1993; 

Conant and Collins, 1991; Martof et al., 1980

Red fox Vulpes vulpes Whitaker, 1997; U.S. EPA, 1993; Stokes and Stokes,

1986

Red-tailed hawk Buteo jamaicensis Terres, 1980; U.S. EPA, 1993; Stokes and Stokes,

1996

River otter Lutra canadensis Whitaker, 1997; U.S. EPA, 1993; Niering, 1985;

Stokes and Stokes, 1986

(continued)
Table 12-1. (continued)

Section 12.0 Ecological Exposure Factors

Species Scientific Name References

12-4

Short-tailed shrew Blarina brevicauda Whitaker, 1997; U.S. EPA, 1993; Stokes and Stokes,

1986

Short-tailed weasel Mustela erminea King, 1983; Sample et al., 1997; Whitaker, 1997

Snapping turtle Chelydra serpentina Martof et al., 1980; U.S. EPA, 1993; Behler and

King, 1979; Conant and Collins, 1991

Southern hognose 

snake

Heterodon simus Behler and King, 1979; Jordan, 1998; Martoff et al.,

1980; Conant and Collins, 1991

Spotted sandpiper Actitis macularia Terres, 1980; U.S. EPA, 1993; Stokes and Stokes,

1996

Tree swallow Tachycineta bicolor Terres, 1980; Sample et al., 1997; Stokes and Stokes,

1996

Western meadowlark Sturnella neglecta Terres, 1980; Sample et al., 1997;

Stokes and Stokes, 1996

White-tailed deer Odocoileus virginianus Whitaker, 1997; Stokes and Stokes, 1986; Smith,

1991

The pathways through which each receptor species may be exposed were determined by the

species’ dietary preferences. For example, strict herbivores are exposed through ingestion of

vegetation but not through ingestion of animal prey items; species whose diet includes animal

prey are exposed through prey ingestion, and so on. Exposures through ingestion of soil,

sediment, and surface water was determined by the documented foraging and feeding behavior

of each species. 

The generalized equation for calculating ecological exposure dose is the following:

(12-1)

where

CRfood = consumption rate of food

FoodConcHabRange = effective concentration in all food items, weighted by

prey preferences

CtssAveHabRange = average contaminant concentration in surficial soil in a

home range

CRfracsoil = soil dietary fraction for each receptor
Section 12.0 Ecological Exposure Factors

12-5

ConcWaterTotAveHabRange = total average concentration in water for each home range

CRwater = consumption rate of water

BodyWtRec = receptor body weight

AreaFracHabRange = fraction of the receptor’s home range comprised by the

habitat.

12.1 Parameters Collected

The variables used in the Ecological Exposure Module are shown in Table 12-2, along

with the data source and notes on whether the variable is represented by a distribution or a fixed

value. The body weight and ingestion rate parameters are characterized by fixed values; dietary

composition, or the amount of each food item eaten, is characterized by a uniform distribution

between reported minimum and maximum values. In addition, the variable PreyType is

addressed in this section. While no data collection was required for this parameter, prey items

were assigned to nine prey categories (PreyType) for use in the Ecological Exposure Module.

In general, the ecological exposure factors are for the mean adult body weight for the

species; male and female weights are combined, and juvenile body weights are not considered. 

Although some data are reported by age or sex, not enough of these data exist to develop

exposure factors for juveniles or for males versus females for an adequate number of species.

Moreover, age- or sex-specific uptake factors and toxicological benchmarks are not available for

ecological receptors. Therefore, consumption rates and prey preferences were estimated for

average adults only.

Dietary composition for each receptor species varies depending on habitat. For example,

raccoons are assumed to eat a variety of vegetation and animal prey wherever they occur; 

however, when they occur in waterbody margin habitats, aquatic prey are included in their

dietary composition. In an upland forest or a residential habitat, only terrestrial prey are

included. 

12.2 Data Sources

The following documents were the principal data sources for the ecological exposure

factors used in the representative national data set:

# U.S. EPA (Environmental Protection Agency). 1993. Wildlife Exposure Factors

Handbook. EPA/600/R-93/187. Office of Research and Development,

Washington, DC. December.

# Sample, B.E., M.S. Alpin, R.A. Efroymson, G.W. Suter, and C.J.E. Welsh. 1997. 

Methods and Tools for Estimation of the Exposure of Terrestrial Wildlife to

Contaminants. ORNL/TM-13391, Office of Environmental Policy and

Assistance. Oak Ridge National Laboratory, Oak Ridge, TN. October.
12-6

12-6

Table 12-2. Parameters Collected

Variable Name Description Principal Data Sources DistBodyWt_rec Body weight for each receptor U.S. EPA, 1993; Sample et al., 1997; American Society of

Mammalogists,a U.S. Army Corps of Engineers2

Fixe

CR_food Food consumption rate for each

receptor

U.S. EPA, 1993 Fixe

weig

CR_water Water consumption rate for each

receptor

U.S. EPA, 1993 Fixe

weig

CRfrac_sed Percentage of food consumption

consisting of sediment

U.S. EPA, 1993 Fixe

CRfrac_soil Percentage of food consumption

consisting of soil

U.S. EPA, 1993 Fixe

MinPreyPref_HabRange Minimum dietary preference for

food items found in home range

U.S. EPA, 1993; Sample et al., 1997; American Society ofMammalogists,a U.S. Army Corps of Engineersb

Mindistr

MaxPreyPref_HabRange Maximum dietary preference for

food items found in home range

U.S. EPA, 1993; Sample et al., 1997; American Society ofMammalogists,a U.S. Army Corps of Engineersb

Maxdistr

AreaFracHabRangec Home range size U.S. EPA, 1993; Sample et al., 1997; American Society of

Mammalogists,a U.S. Army Corps of Engineersb

Fixe

a The American Society of Mammalogists’ Mammalian Species Series comprises individually published monographs on single species

publication vary for each species. 

b The U.S. Army Corps of Engineers’ Species Profile Series comprises individually published monographs on single species. Authors 

vary for each species.

c Home range size data were used in the site layout data processing step to calculate AreaFracHabRange. Although home range size is not 

the ecological exposure module, these data were collected from the same sources as other species-specific exposure factors and are do
Section 12.0 Ecological Exposure Factors

12-7

# U.S. Army Corps of Engineers’ Species Profile Series. Various authors and

publication dates. 

# American Society of Mammalogists’ Mammalian Species Series. Various authors

and publication dates.

Table 12-2 indicates the principal data source for each parameter. For species-specific

body weight, dietary composition, and home range size, the primary source of data was the

Wildlife Exposure Factors Handbook (the Handbook) (U.S. EPA, 1993). The Handbook is the

best available compendium of information relevant to ecological exposure. It includes exposure

factors for 34 species of mammals, birds, amphibians, and reptiles. All species included in the

Handbook (U.S. EPA, 1993) have been included in the 3MRA modeling system exposure factor

database, with the exception of the harbor seal, which inhabits estuarine and marine habitats not

addressed in the example data set. In addition, algorithms for estimating ingestion rates based on

body weight were taken from the Handbook (U.S. EPA, 1993). 

Similar data for an additional 15 species of birds and mammals (Black-tailed jackrabbit,

burrowing owl, Cooper’s hawk, coyote, Great Basin pocket mouse, green heron, kit fox, little

brown bat, least weasel, long-tailed weasel, short-tailed weasel, mule deer, pine vole, tree

swallow, and western meadowlark) were taken from Sample et al. (1997). The species addressed

in Sample et al. (1997) were chosen by the authors specifically to complement those in the

Handbook (U.S. EPA, 1993), and thus provide complementary data. 

The American Society of Mammalogists’ Mammalian Species Series provided additional

prey preference, home range size, and body weight data on seven of the species in the Handbook

(U.S. EPA, 1993) and Sample et al. (1997), and provided primary data for an additional two

mammals (beaver and white-tailed deer). 

The U.S. Army Corps of Engineers’ Species Profile Series provided data on eight

additional species – one mammal, two reptiles, two amphibians, and three birds. These species

profiles are part of a study of wildlife species on military reservations in the southeastern United

States and, therefore, emphasize species found in that region. Of the receptors selected from this

source, however, only the amphibians and reptiles (alligator snapping turtle, southern hognose

snake, gopher frog and flatwoods salamander) are restricted to the southeastern United States. 

Because data on herpetofauna are generally scarce, these four species are included in the

receptor list, although they are included in the exposure analysis only at sites located within their

respective areas of distribution.

Additional sources were identified to supplement the prey preference data from the

principal sources. The dietary information in the Handbook (U.S. EPA, 1993) and Sample et al.

(1997) consists of reported food items from field studies. Thus, the data reflect the dietary

composition of a single or a few individuals at particular study sites, in some cases over a

relatively short time period. The 3MRA modeling system exposure assessment, on the other

hand, is based on hypothetical food webs intended to reflect all of the receptor species’ potential

dietary items. As such, the prey preference data required by the ecological exposure module

should reflect the potential food intake for the species in all habitats and regions where it occurs. 

Therefore, more generalized dietary composition data were taken from numerous field guides
Section 12.0 Ecological Exposure Factors

12-8

and wildlife encyclopedias (e.g., several of the National Audubon Society field guides and the

Peterson field guides; Terres, 1980; Martof et al., 1980). All references used to collect

ecological exposure data are listed in Table 12-1 and in the reference section (Section 12.5).

Soil and sediment ingestion data were taken from the Handbook (U.S. EPA, 1993) and

from several additional references, each with data on one or a few species. See Section 12.3.4

for further discussion of these data sources.

12.3 Methodology

Methods for developing exposure factors from wildlife data extracted from various 

sources are detailed in the Handbook (U.S. EPA, 1993). Those methods were followed

substantially in the data collection effort for the representative national data set. Based on

information in the Handbook (U.S. EPA, 1993) and in the other sources listed previously, a

database was developed containing all available data relevant to ecological exposures for the 52

selected receptor species. Most of the data were extracted from the Handbook (U.S. EPA, 1993)

and from Sample et al. (1997). Both the Handbook (U.S. EPA, 1993) and Sample et al. (1997)

are compilations of data from many different references and, therefore, include multiple values

for each species for a particular data category (e.g., multiple body weights for otter). In some

cases, the reported values are the mean of the data collected for a single study; in other cases, the

reported values reflect a single measurement. In all cases, all reported values were entered into

the database, including means, minima, and maxima. Single reported values were entered as

mean values. Data collected from additional sources were treated in the same manner. These

data were then processed to generate the appropriate inputs for the module. The following

subsections document the data processing methods for each ecological exposure parameter.

Section 12.3.6 addresses the quality assurance and quality control (QA/QC) of data collection

and processing.

12.3.1 Receptor Body Weights

Data on the body weights of individual receptor species were taken from several primary

sources that represent a compilation of the results of many separate studies. The primary sources

used included the following:

# U.S. EPA (1993)

# Sample et al. (1997)

# American Society of Mammalogists’ Mammalian Species Series

# U.S. Army Corps of Engineers’ Species Profile Series.

Values were collected and assembled in the ecological exposure database. Then, a mean

value was calculated so that a single datum represented body weight for each species. When

data from multiple studies were reported in a single reference (e.g., the Handbook [U.S. EPA,

1993]), the geometric mean of the adult body weights from each study was calculated. In some

cases, body weight data were presented separately for males and females. In this instance, the

average of the geometric means for males and females was used. Body weights collected from

field guides generally consisted of average adult values. Body weights identifiable as juvenile or

preadult weights were not included in the species average. The mean body weights represent
Section 12.0 Ecological Exposure Factors

12-9

(12-2)

data from multiple local investigations as well as from national or regional averages. They are

assumed to collectively represent a national mean. 

The following assumptions are inherent in this manipulation of body weight data:

# Some reported data are accompanied by an indication of the age of the individual

studied; age data are relevant to body weights. In some cases, an age in months

or years is reported, while in others a life stage such as fledgling, juvenile, or

subadult is reported. These data were standardized in the database to indicate

adults for individuals that have reached sexual maturity and juveniles for all other

ages.

# Individual body weights were derived to represent receptors nationally. This

derivation was generally based on local scale data from studies distributed

throughout the United States. For some species, however, only one or a few

reported body weights were available.

# A single value is assumed to represent both males and females.

12.3.2 Food Ingestion Rates

Food and water consumption rates were calculated for each receptor species using

Nagy’s (1987) allometric equations as reported in the Handbook (U.S. EPA, 1993). The

equations correlate food and water intake to body weight in free-living wildlife species. 

Separate regression equations were used for mammals and birds. The equations and associated

values follow.

Food ingestion rate 

where

Y = food ingestion rate, g DW/d

Wt = representative body weight of receptor species, g WW

a = empirical coefficient

b = empirical coefficient.

Mean adult body weights were estimated as described in Section 12.3.1. The values used for the

empirical coefficients a and b, as presented in the Handbook (U.S. EPA, 1993), are presented in

Table 12-3. The estimations were based on average, gender-neutral body weights and do not

account for differences in size, season, habitat, or activity level. Ingestion rates were

subsequently converted to a wet weight basis assuming 85 percent moisture content of food.
Section 12.0 Ecological Exposure Factors

12-10

(12-3)

(12-4)

Table 12-3. Empirical Coefficients Used to Calculate Food Ingestion Rates

Species Group/Subgroup a b

Birds 0.64 0.651

Mammals 0.23 0.822

Source: U.S. EPA, 1993.

12.3.3 Water Ingestion Rates

Receptor species’ consumption rates for water also were derived based on body weights. 

Calder and Braun (1983), as cited in the Handbook (U.S. EPA, 1993), developed an equation for

drinking water ingestion for birds. This equation is presented in Equation 12-3.

Water ingestion rate for birds

where

WI = drinking water ingestion, L/d

Wt = representative body weight of receptor species, kg.

This equation was derived based on a data set representing 21 species with a body weight range

of 11 to 3,150 g. Birds, in general, drink less water than mammals of equivalent body weight. 

Calder and Braun (1983) developed a parallel equation for mammals, as shown in Equation 12-4.

Drinking water ingestion for mammals

where

WI = drinking water ingestion, L/d

Wt = representative body weight of receptor species, kg.

No similar allometric equation is available for relating body weight to drinking water

ingestion for reptiles and amphibians. Therefore, a default value of 0.0001 was used for water

ingestion in all herpetofauna.
Section 12.0 Ecological Exposure Factors

12-11

The following assumptions are inherent in the derivation of the receptor species drinking

water ingestion rates:

# The estimations were based on average, gender-neutral body weights and do not

account for differences in size, season, habitat, or activity level. 

# Additional sources of water, including water derived from ingested food, were not

accounted for. Depending on dietary composition, some species derive more

water from food items than do others.

12.3.4 Consumption Rate of Surficial Soil/Sediment

Consumption rates for surficial soil and sediment were taken from the Handbook

(U.S. EPA, 1993) and the following additional references:

# Arthur and Gates (1988)

# Arthur and Alldredge (1979) 

# Beyer et al. (1994)

# Mayoh and Zach (1986).

Sediment and soil ingestion rates were reported as a fraction of the total dietary ingestion.

The fractions were applied to the ingestion rates estimated as described in Section 12.3.2.

The values were reported as sediment/soil ingestion rates, without distinguishing what

proportion was sediment versus soil. The Ecological Exposure Module, however, uses discreet

constituent concentrations in soil and sediment. Therefore, receptor species were assigned soil or

sediment ingestion as a function of their feeding patterns. Those species feeding entirely on

terrestrial prey and food items were assumed to consume soil, and the reported sediment/soil

ingestion rate was applied entirely to soil. Those receptors feeding on aquatic prey and food

items, or on a combination of aquatic and terrestrial prey and food items, were assumed to ingest

only sediment. 

For those species for which sediment/soil ingestion rates were not available, the reported

ingestion rate of the most similar species was used. Similarity was based first on faunal class

(i.e., mammal, bird, reptile, amphibian), second on size, and third on feeding behavior. Data

were available for only two species of herpetofauna, the eastern box turtle and the painted turtle.

Therefore, small herpetofauna with mixed diets (e.g., frogs, salamanders) were given the same

rate as the eastern box turtle, and larger herpetofauna that eat a significant proportion of fish

(e.g., snapping turtles and aquatic snakes) were given the same rate as the painted turtle. 

The following assumptions are inherent in the derivation of the receptor species’ surficial

 soil/sediment ingestion rates:

# Soil and sediment ingestion were treated as mutually exclusive because the data

do not specify which medium was reported. Many receptors probably ingest a

combination of soil and sediment (e.g., raccoon).
Section 12.0 Ecological Exposure Factors

12-12

# Data on soil ingestion were lacking for most receptor species; therefore, available

values were used for species expected to have a similar diet and feeding behavior. 

12.3.5 Maximum/Minimum Dietary Preferences

The Ecological Exposure Module includes an algorithm to construct a unique, randomly

selected diet for each receptor species at each site where it occurs. This algorithm reflects the

variability in receptor species’ dietary composition. Dietary preference data required by the

ecological exposure model includes a list of potential diet items for each species and the

maximum and minimum proportion of the species’ diet that each item can comprise. Diet items

are categorized as one of 17 types of prey recognized by the 3MRA modeling system. The prey

categories are shown in Table 12-4. 

Table 12-4. Prey Categories

Worms

Other invertebrates

Small mammals

Small birds

Small herpetofauna

Herbivorous vertebrates

Omnivorous vertebrates

Benthic filter feeders

Trophic level (T3) fish

Trophic level (T4) fish

Aquatic plants

Exposed fruit

Exposed vegetables

Forage

Grains

Roots

Silage

For example, prey preference data on the Eastern box turtle are as follows:

Diet Item Percentage of Diet

Worms 3 to 60 

Forage 13 to 39

Fruits 5 to 33

Other invertebrates 8 to 22

Small herpetofauna 0 to 10

Small mammals 0 to 10

Information on receptor species’ dietary composition comes from a wide range of data

sources and is of two general types. Some data consist of reported quantities of certain items

eaten by particular individuals in a localized or site-specific study. These data consist of

measured stomach contents, nest or burrow contents, or counts of items observed to be eaten

during a particular time span. The principal sources for this type of data are the Handbook (U.S.

EPA, 1993) and Sample et al. (1997). The second type of information consists of qualitative

reports of items documented to be eaten. These reports reflect a compilation of observations and

measurements for the species in general and are reported as descriptions of the species’ potential

diet. The principal sources of this type of data are the Army Corps of Engineers’ Species Profile
Section 12.0 Ecological Exposure Factors

12-13

Series, the American Society of Mammalogists’ Mammalian Species Series, and the various

field guides and handbooks listed in Table 12-1.

The Ecological Exposure Module requires data on the full range of potential diet items

across all habitats where each species could occur. In addition, it requires quantified data –

maxima and minima. Therefore, the two general types of data for each receptor were combined,

and dietary profiles were developed for each receptor species. The profiles include each

documented diet item for each species, whether the item was reported in a quantitative or

qualitative form. Maximum and minimum values were generated for each item through a

subjective process implemented by project ecologists. In this process, the qualitative

information was evaluated, and an estimated dietary fraction was assigned to each item. Then, all

reported and estimated dietary fractions were compared, and the minimum and maximum values

were identified for each diet item. 

The assignment of estimated dietary fractions was made by a single ecologist to maintain

consistency in interpreting qualitative descriptions. In addition, certain decision rules were

followed for all assignments. References to a diet item that implied a single most significant

component, such as “primary food source,” “bulk of the diet,” and “consumes mostly,” were

assigned a minimum of 50 percent dietary composition. Items that are of secondary importance

but that would always make up at least some portion of the diet were assigned a minimum of

10 percent. Descriptions implying occasional sources of food were given a minimum of zero

(thus indicating that some individuals under some circumstances do not consume the item at all)

and a maximum of 25 percent. A few species have relatively limited diets and eat only one diet

item. For example, the cerulean warbler eats insects almost exclusively. In these cases, the

exclusive diet item (insects) was assigned a minimum of 95 percent and a maximum of

100 percent. The quantified dietary profiles were entered into the exposure factor database as

maximum and minimum values for each prey category. 

The different data sources report vegetative dietary constituents in various terms ranging

from a list of food items by species name to general categories such as seeds and nuts or

vegetation. Consequently, the data for vegetation constituents were standardized in the database

using terms recognized by the exposure module and coded according to farm food chain codes

for compatibility with the farm food chain and terrestrial food web modules. Table 12-5 shows

the food categories most frequently reported in the literature and their respective farm food chain

codes. 

Assumptions inherent in the processing of these data include the following:

# Data from a variety of sources were collected and combined to represent receptor

species’ diets; therefore, the values used were intended to be representative of the

species throughout their range and habitat types.

# Qualitative diet information was subjectively interpreted and given numeric

values. These values were combined with site- or study-specific quantitative data

to derive maximum and minimum values.
Section 12.0 Ecological Exposure Factors

12-14

Table 12-5. Farm Food Chain Codes for Wildlife Diet Items

Farm Food Chain

Code Dietary Items Included

Forage Forbs, grass(es), other plant(s), plant(s), shrubs, terrestrial plants, trees,

unclassified plant(s), unidentified plant(s), vegetation, woody plants

Silage Crops, corn

Grains Seeds, nuts 

Exposed fruit Fruits, fruits/seeds (reported as a single item)

Exposed vegetation Fern(s), fungi, fungus, cactus, dicot shoots, monocot shoots

Root Root

# When fish were a reported dietary item, the fish's trophic level was included for

use in the aquatic food web module. When the fish species name was reported, its

trophic level was extracted from trophic level analyses in EPA’s Great Lakes

Study (U.S. EPA, 1995). In all other cases, the trophic level for fish prey was

assumed to be T3 or T4 based on the size of the predator (receptor species). 

Small receptors were assumed to eat T3 fish. For large receptors, it was assumed

that 50 percent of the fish they eat are T3 and 50 percent are T4. None of the

primary exposure data sources included information on the trophic level of prey

items.

12.3.6 Home Range Size

Home range, or territory size, was used to estimate the proportion of the diet taken from

the potentially contaminated area. For species with very small territories (e.g., mice, voles), the

entire home range is likely to fall within the contaminated area. For larger or wider ranging

species (e.g., the bald eagle), much of a receptor’s diet could come from outside the

contaminated area. The variable used in the ecological exposure module to reflect the proportion

of a receptor’s diet taken from the contaminated area is AreaFracHabRange. Home range size data

were used in the site layout data processing step to calculate AreaFracHabRange by dividing the

species’ home range area by the area of the species’ habitat located on a site. A detailed

discussion of the AreaFracHabRange variable is presented in the documentation of the ecological

exposure module. 

Home range data were available for all but 9 of the 52 receptor species and were found

primarily in the Handbook (U.S. EPA, 1993), Sample et al. (1997), the Army Corps of

Engineers’ Species Profile Series, and the American Society of Mammalogists’ Mammalian

Species Series. Species for which no data were available were assigned the home range size of a

similar species with similar feeding habits. Various metrics are reported in the literature for the

size of the area used by a receptor. These metrics include feeding or foraging radius, feeding or

foraging distance, and home range or territory size. In most cases (particularly, the Handbook
Section 12.0 Ecological Exposure Factors

12-15

[U.S. EPA, 1993]), the terminology for area size was discussed and defined. In other sources,

when no definition of terms was provided, judgments were made based on the context of the data

and comparison with other reports on the same species. In most cases, the size of the area used

by a species for foraging and feeding was reported in hectares or acres and referred to as the

home range or territory. When a linear distance was reported, it was assumed to represent a

radius. When a radius was reported, it was assumed to describe a circular area around a nest or

some essential physical feature. All home range size data were entered into the exposure factors

database, and the midpoint between the minimum and maximum values was calculated for each

species. The home ranges were assumed to be circular.

In the site layout processing step, receptor species’ home ranges were placed within

delineated habitats where the species occur. Section 13.0 provides a full description of habitat

delineation and placement of home ranges. As explained in Section 13.0, home range placement

proved inordinately resource-intensive. Therefore, a binning approach was adopted to reduce the

number of home ranges that required placement in a geographic information system (GIS).

Using this approach, each receptor’s average home range size was assigned to one of four bins. 

Each bin comprised a range of home range sizes, as follows:

# Bin 1 – Home range = or <100,000 m2

# Bin 2 – Home range >100,000 m2 and <1 million m2

# Bin 3 – Home range = or >1 million m2, and <10 million m2

# Bin 4 – Home range = or >10 million m2.

Because receptor exposure dose, as calculated in the ecological exposure module, is

adjusted based on the proportion of the home range that falls within the contaminated area, the

binning approach potentially underestimates the exposure dose for receptors at the low end of

each range. For example, the meadow vole has an average home range size of 416 m2; however,

because it falls within Bin 1, its home range is assumed to be 100,000 m2. Thus, the proportion

of the meadow vole’s diet taken from contaminated habitat will be calculated as the proportion

of the 100,000-m2 home range that falls within the contaminated area. Obviously, in certain

cases, this will be a significantly smaller proportion of the diet than would be estimated if the

true mean home range size (416 m2

) were used.

The following assumptions are inherent in the processing of home range size data:

# Calculated averages were assumed to reflect the home range size for a species in

all of the habitats where it occurs, while available data may come from a single

habitat type. In fact, habitat type and quality affect foraging distance. For

example, a white-tailed deer may cover a larger area when foraging in a forest

than when feeding in a crop field. 

# Average home range sizes also were assumed to reflect all regions of the United

States and year-round food availability. Some reported home range data were for

particular regions and seasons; no attempt was made to distinguish home range

size by region or season.
Section 12.0 Ecological Exposure Factors

12-16

12.3.7 Data Entry and Data Processing Quality Assurance/Quality Control

The QA/QC functions for data collection of ecological exposure factors consist of

ensuring that data have been interpreted and extracted correctly (i.e., Technical QA/QC) and 

verifying that data have been entered correctly (i.e., data entry QA/QC). Detailed QA records

are maintained by the project QA Officer (QAO).

12.3.7.1 Technical Quality Assurance/Quality Control. The sources used to obtain

the exposure factor data are considered to be authoritative references and, therefore, data

extracted from them are assumed to be of high quality. Data extracted from primary literature

sources have been reviewed by senior ecologists to determine the quality of the exposure factors. 

Methods for extracting and combining data (e.g., calculating mean values) as well as the

assumptions used for interpreting and standardizing data (e.g., assigning age data as adult or

juvenile or assigning food types to farm food chain categories) were developed with the

oversight and review of senior ecologists.

12.3.7.2 Data Entry Quality Assurance/Quality Control. Entry of raw data into the

exposure factors database was checked against the source by a staff member other than the one

who entered the data. At least 50 percent of entries from each source were checked. All data

processing, such as calculation of means, was checked by a staff member other than the one who

performed the calculation or set up the calculation spreadsheet. A QA check of at least 10

percent of the results of the spreadsheet macros used to manipulate data was made against the

original spreadsheets.

12.4 Results

Tables presenting the ecological exposure data used in the 3MRA modeling system are

presented in the appendixes to this section. Appendix 12A includes the following tables: 

# Table 12A-1 – Mean body weights by receptor

# Table 12A-2 – Food ingestion rates for mean body weight by receptor

# Table 12A-3 – Water ingestion rates for mean body weight by receptor

# Table 12A-4 – Soil ingestion rates as a fraction of total ingestion

# Table 12A-5 – Sediment ingestion rates as a fraction of total ingestion.

Appendix 12B includes prey preference tables:

# Table 12B-1 – Minimum prey preferences

# Table 12B-2 – Maximum prey preferences.

Appendix 12C includes receptor home ranges and assignments to size bins. 
Section 12.0 Ecological Exposure Factors

12-17

12.5 References

Anderson, Allen E., and Olof C. Wallmo. 1984. Odocoileus hemionus. In: Mammalian Species.

Volume 219 pp. 1-9. The American Society of Mammalogists.

Arthur, W. J., and A. W. Alldredge. 1979. Soil ingestion by mule deer in northcentral Colorado.

Journal of Range Management, 32(1):67-71. January.

Arthur, W. John, III, and Robert J. Gates. 1988. Trace element intake via soil ingestion in

pronghorns and in black-tailed jackrabbits. Journal of Range Management, 41(2):162-

166. March.

Bekoff, Marc. 1977. Canis latrans. In: Mammalian Species. Volume 79 pp. 1-9. The American

Society of Mammalogists.

Beyer, W. Nelson, Erin E. Connor, and Sarah Gerould. 1994. Estimates of soil ingestion by

wildlife. Journal of Wildlife Management, 58(2):375-382.

Calder, William A., III, and Eldon J. Braun. 1983. Scaling of osmotic regulation in mammals

and birds. American Journal of Physiology, 244(13):R601-R606.

Chapman, Joseph A., J. Gregory Hockman, and C. Ojeda. 1980. Sylvilagus floridanus. In:

Mammalian Species. Volume 136 pp. 1-8. The American Society of Mammalogists.

Evans, Darrell E. and Richard A. Fischer. 1997. Species Profile: Cerulean Warbler (Dendroica

cerulea) on Military Installations in the Southeastern United States. SERDP-97-12.

Headquarters, U.S. Army Corps of Engineers. U.S. Army Corps of Engineers, Strategic

Environmental Research and Development Program, Waterways Experiment Station,

Vicksburg, MS. October.

Hall, Stephen P. and Harry E. LeGrand, Jr., and Richard A. Fischer. 1997. Species Profile:

Loggerhead Shrike (Lanius ludovicianus) on Military Installations in the Southeastern

United States. SERDP-97-8. Headquarters, U.S. Army Corps of Engineers. U.S. Army

Corps of Engineers, Strategic Environmental Research and Development Program,

Waterways Experiment Station, Vicksburg, MS. September.

Jenkins, Stephen H., and Peter E. Busher. 1979. Castor canadensis. In: Mammalian Species.

Volume 120 pp. 1-8. The American Society of Mammalogists.

King, C. M. 1983. Mustela erminea. Mammalian Species. American Society of Mammologists

195:(1-8).

Lane, John J. and Richard A. Fischer. 1997. Species Profile: Southeastern American Kestrel

(Falco sparverius paulus) on Military Installations in the Southeastern United States.

SERDP-97-4. Headquarters, U.S. Army Corps of Engineers. U.S. Army Corps of

Engineers, Strategic Environmental Research and Development Program, Waterways

Experiment Station, Vicksburg, MS. August.
Section 12.0 Ecological Exposure Factors

12-18

Lotze, Joerg Henner, and Sydney Anderson. 1979. Procyon lotor. In: Mammalian Species.

Volume 119 pp. 1-8. The American Society of Mammalogists.

MacMahon, James A. 1985. Deserts. In: The Audobon Society Nature Guides. Alfred A. Knopf,

Inc., New York, NY.

Mayoh, Keith R., and Reto Zach. 1986. Grit ingestion by nestling tree swallows and house

wrens. Canadian Journal of Zoololgy, 64:2090-2093.

McGrew, John C. 1979. Vulpes macrotis. In: Mammalian Species. Volume 123 pp. 1-6. The

American Society of Mammalogists.

Nagy, K. A. 1987. Field metabolic rate and food requirement scaling in mammals and birds.

Ecological Monographs, 57(2):111-128.

Niering, William A. 1985. Wetlands. In: The Audubon Society Nature Guides. Alfred A. Knopf,

Inc., New York, NY.

Sample, B. E., M. S. Aplin, R. A. Efroymson, G. W. Suter II, and C. J. E. Welsh. 1997. 

Methods and Tools for Estimation of the Exposure of Terrestrial Wildlife to

Contaminants. ORNL/TM-13391. Office of Environmental Policy and Assistance, U.S.

Department of Energy. Oak Ridge National Laboratory, Oak Ridge, TN. October.

Schaefer, Joe, and Mary Sargent. 1990. The Florida Black Bear: A Threatened Species. SSWIS-25. Cooperative Urban Wildlife Program, Gainesville, FL. December. pp. 1-3.

Smith, Winston Paul. 1991. Odocoileus virginianus. In: Mammalian Species. Volume 388 pp.

1-13. The American Society of Mammalogists.

Stokes, Donald, and Lillian Stokes. 1996. Stokes field guide to birds. Eastern region. In: Stokes

Field Guides. 1st Edition. Little, Brown and Company, Boston, MA.

Stokes, Donald W., and Lillian Q. Stokes. 1986. A guide to animal tracking and behavior. In:

Stokes Nature Guides. Little, Brown & Company, Boston, MA.

Sutton, A. and M. Sutton. 1985. The Audubon Society Nature Guides: Eastern Forests. Alfred

A. Knopf, Inc. New York.

Terres, John K. 1980. The Audubon Society Encyclopedia of North American Birds. Alfred A.

Knopf, Inc., New York, NY.

U.S. EPA (Environmental Protection Agency). 1993. Wildlife Exposure Factors Handbook.

Volumes I and II. EPA/600/R-93/187. U.S. Environmental Protection Agency, Office of

Health and Environmental Assessment and Office of Research and Development,

Washington, DC. December.
Section 12.0 Ecological Exposure Factors

12-19

Whitaker, John O., Jr. 1997. Field guide to North American mammals. In: National Audobon

Society. 2nd Edition. Alfred A. Knopf, Inc., New York, NY.

Whitney, Stephen. 1985. Western forests. In: The Audubon Society Nature Guides. Alfred A.

Knopf, Inc., New York, NY.

Willner, Gale R., George A. Feldhamer, Elizabeth E. Zucker, and Joseph A. Chapman. 1980. 

Ondatra zibethicus. In: Mammalian Species. Volume 141 pp. 1-8. The American Society

of Mammalogists.
Section 12.0 Ecological Exposure Factors

12-20

This page intentionally left blank
Appendix 12A Ecological Exposure Factors

12-21

Appendix 12A

Ecological Exposure Factors

Table 12A-1. Mean Adult Body Weight (kg) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12-23

Table 12A-2. Food Ingestion Rates (kg/d wet weight) . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12-25

Table 12A-3. Water Ingestion Rates (L/d) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12-27
Appendix 12A Ecological Exposure Factors

12-22

This page intentionally left blank
Appendix 12A Ecological Exposure Factors

12-23

Table 12A-1. Mean Adult Body Weight (kg)

Receptor Index Receptor Species BodyWtRec

1 Alligator snapping turtle 50.40

2 American kestrel 0.12

3 American robin 0.08

4 American woodcock 0.18

5 Bald eagle 3.75

6 Beaver 19.31

7 Belted kingfisher 0.15

8 Black bear 128.87

9 Black-tailed jackrabbit 2.42

11 Burrowing owl 0.15

12 Canada goose 3.00

13 Cerulean warbler 0.01

14 Cooper's hawk 0.40

15 Coyote 13.13

16 Deer mouse 0.02

17 Eastern box turtle 0.38

18 Eastern cottontail rabbit 1.23

22 Great Basin pocket mouse 0.02

23 Great blue heron 2.23

25 Green heron 0.23

26 Herring gull 1.09

27 Kit fox 1.80

28 Least weasel 0.04

29 Lesser scaup 0.79

30 Little brown bat 0.01

31 Loggerhead shrike 0.05

32 Long-tailed weasel 0.19

33 Mallard duck 1.17

34 Marsh wren 0.01

35 Meadow vole 0.02

36 Mink 0.99

37 Mule deer 75.47

38 Muskrat 0.87

39 Northern bobwhite 0.19

40 Northern water snake 0.21

(continued)
Table 12A-1. (continued)

Appendix 12A Ecological Exposure Factors

Receptor Index Receptor Species BodyWtRec

12-24

41 Osprey 1.60

42 Painted turtle 0.24

43 Pine vole 0.03

44 Prairie vole 0.04

45 Raccoon 5.69

46 Racer 0.11

47 Red fox 4.53

48 Red-tailed hawk 1.13

49 River otter 8.66

50 Short-tailed shrew 0.02

51 Short-tailed weasel 0.20

52 Snapping turtle 5.30

53 Southern hognose snake 0.10

54 Spotted sandpiper 0.04

55 Tree swallow 0.02

56 Western meadowlark 0.11

57 White-tailed deer 69.42
Appendix 12A Ecological Exposure Factors

12-25

Table 12A-2. Food Ingestion Rates (kg/d wet weight)

Receptor

Index Receptor Species

CR_Food

(kg/d ww)

1 Alligator snapping turtle 0.35

2 American kestrel 0.10

3 American robin 0.072

4 American woodcock 0.12

5 Bald eagle 0.91

6 Beaver 5.1

7 Belted kingfisher 0.11

8 Black bear 24

9 Black-tailed jackrabbit 0.93

11 Burrowing owl 0.11

12 Canada goose 0.78

13 Cerulean warbler 0.018

14 Cooper's hawk 0.21

15 Coyote 3.7

16 Deer mouse 0.018

17 Eastern box turtle 0.0079

18 Eastern cottontail rabbit 0.53

22 Great Basin pocket mouse 0.016

23 Great blue heron 0.65

25 Green heron 0.15

26 Herring gull 0.41

27 Kit fox 0.73

28 Least weasel 0.032

29 Lesser scaup 0.33

30 Little brown bat 0.0092

31 Loggerhead shrike 0.052

32 Long-tailed weasel 0.11

33 Mallard duck 0.42

34 Marsh wren 0.020

35 Meadow vole 0.019

36 Mink 0.45

37 Mule deer 16

38 Muskrat 0.40

39 Northern bobwhite 0.13

(continued)
Table 12A-2. (continued)

Appendix 12A Ecological Exposure Factors

Receptor

Index Receptor Species

CR_Food

(kg/d ww)

12-26

40 Northern water snake 0.0050

41 Osprey 0.52

42 Painted turtle 0.0055

43 Pine vole 0.022

44 Prairie vole 0.033

45 Raccoon 1.9

46 Racer 0.0031

47 Red fox 1.6

48 Red-tailed hawk 0.41

49 River otter 2.6

50 Short-tailed shrew 0.014

51 Short-tailed weasel 0.12

52 Snapping turtle 0.060

53 Southern hognose snake 0.0028

54 Spotted sandpiper 0.049

55 Tree swallow 0.031

56 Western meadowlark 0.089

57 White-tailed deer 15
Appendix 12A Ecological Exposure Factors

12-27

Table 12A-3. Water Ingestion Rates (L/d)

Receptor Index Receptor Species

CR_Water

(kg/d)

1 Alligator snapping turtle 0.00010

2 American kestrel 0.014

3 American robin 0.011

4 American woodcock 0.019

5 Bald eagle 0.14

6 Beaver 1.4

7 Belted kingfisher 0.016

8 Black bear 7.8

9 Black-tailed jackrabbit 0.22

11 Burrowing owl 0.017

12 Canada goose 0.12

13 Cerulean warbler 0.0025

14 Cooper's hawk 0.032

15 Coyote 1.00

16 Deer mouse 0.0029

17 Eastern box turtle 0.00010

18 Eastern cottontail rabbit 0.12

22 Great Basin pocket mouse 0.0026

23 Great blue heron 0.10

25 Green heron 0.022

26 Herring gull 0.063

27 Kit fox 0.17

28 Least weasel 0.0056

29 Lesser scaup 0.050

30 Little brown bat 0.0014

31 Loggerhead shrike 0.0076

32 Long-tailed weasel 0.022

33 Mallard duck .066

34 Marsh wren .0028

35 Meadow vole 0.0030

36 Mink 0.098

37 Mule deer 4.8

38 Muskrat 0.088

39 Northern bobwhite 0.019

(continued)
Table 12A-3. (continued)

Appendix 12A Ecological Exposure Factors

Receptor Index Receptor Species

CR_Water

(kg/d)

12-28

40 Northern water snake 0.00010

41 Osprey 0.081

42 Painted turtle 0.00010

43 Pine vole 0.0036

44 Prairie vole 0.0057

45 Raccoon 0.47

46 Racer 0.00010

47 Red fox 0.39

48 Red-tailed hawk 0.064

49 River otter 0.69

50 Short-tailed shrew 0.0035

51 Short-tailed weasel 0.023

52 Snapping turtle 0.00010

53 Southern hognose snake 0.00010

54 Spotted sandpiper 0.0071

55 Tree swallow 0.0044

56 Western meadowlark 0.013

57 White-tailed deer 4.5
Appendix 12A Ecological Exposure Factors

12-29

Table 12A-4. Soil Ingestion Rates (percent of total ingestion)

Receptor Index Receptor Species CRfrac_soil

2 American kestrel 1

3 American robin 1

4 American woodcock 10.4

8 Black bear 2.8

9 Black-tailed jackrabbit 6.3

11 Burrowing owl 1

12 Canada goose 8.2

13 Cerulean warbler 0

14 Cooper's hawk 1

15 Coyote 2.8

16 Deer mouse 2

18 Eastern cottontail rabbit 6.3

22 Great Basin pocket mouse 2

27 Kit fox 2.8

28 Least weasel 1

30 Little brown bat 0

31 Loggerhead shrike 1

32 Long-tailed weasel 2.8

35 Meadow vole 2.4

37 Mule deer 6.8

39 Northern bobwhite 9.3

43 Pine vole 2.4

44 Prairie vole 2.4

46 Racer 1

47 Red fox 2.8

48 Red-tailed hawk 1

50 Short-tailed shrew 1

51 Short-tailed weasel 2.8

53 Southern hognose snake 1

55 Tree swallow 1

56 Western meadowlark 0

57 White-tailed deer 6.8
Appendix 12A Ecological Exposure Factors

12-30

Table 12A-5. Sediment Ingestion Rates (percent of total ingestion)

Receptor Index Receptor Species CRfrac_sed

1 Alligator snapping turtle 5.9

5 Bald eagle 5.9

6 Beaver 3.3

7 Belted kingfisher 5.9

17 Eastern box turtle 4.5

23 Great blue heron 9.4

25 Green heron 9.4

26 Herring gull 5.9

29 Lesser scaup 3.3

38 Mallard duck 3.3

34 Marsh wren 0

36 Mink 9.4

38 Muskrat 3.3

40 Northern water snake 5.9

41 Osprey 5.9

42 Painted turtle 5.9

45 Raccoon 9.4

49 River otter 9.4

52 Snapping turtle 5.9

54 Spotted sandpiper 10.4
Appendix 12B Dietary Preferences for Terrestrial Food Web

12-31

Appendix 12B

Dietary Preferences for Terrestrial Food Web

Table 12B-1a. Minimum Prey Preferences in Terrestrial Habitats (percent of diet) . . . . . . 12-33

Table 12B-1b. Minimum Prey Preferences in Waterbody Margin and Wetland Margin 

Habitats (percent of diet) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12-36

Table 12B-2a. Maximum Prey Preferences in Terrestrial Habitats (percent of diet) . . . . . 12-39

Table 12B-2b. Maximum Prey Preferences in Waterbody Margin and Wetland Margin 

Habitats (percent of diet) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12-42
Appendix 12B Dietary Preferences for Terrestrial Food Web

12-32

This page intentionally left blank
12-33

Table 12B-1a. Minimum Prey Preferences in Terrestrial Habitats (percent of diet)

Worms

Other invertebrates

Small mammals

Herbivorous vertebrates

Omnivorous vertebrates

Small birds

Benthic filter feeders

T3 Fish

T4 Fish

Aquatic plants

Exposed fruits

Exposed vegetables

Forage

Grains

Roots

Silage

 NumpreyNumreceptor 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 

1 Alligator snapping turtle -999 0 0 -999 -999 -999 -999 -999 -999 -999 0 -999 -999 -999 -999 -992 American kestrel 0 0.25 0 -999 -999 0 -999 -999 -999 -999 -999 -999 -999 -999 -999 -993 American robin 0.15 0.08 -999 -999 -999 -999 -999 -999 -999 -999 0.07 -999 0 -999 -999 -994 American woodcock 0.6 0.01 -999 -999 -999 -999 -999 -999 -999 -999 -999 -999 0 -999 -999 -995 Bald eagle -999 0 0.1 0 0 0.02 -999 -999 -999 -999 -999 -999 -999 -999 -999 -996 Beaver -999 -999 -999 -999 -999 -999 -999 -999 -999 -999 -999 -999 0.2 -999 0.01 -997 Belted kingfisher -999 0.2 0 -999 -999 -999 -999 -999 -999 -999 -999 -999 0 -999 -999 -998 Black bear -999 0.3 0.01 0 0 -999 -999 -999 -999 -999 0.3 0 0.05 -999 0 9 Black-tailed jackrabbit -999 -999 -999 -999 -999 -999 -999 -999 -999 -999 -999 -999 0.9 -999 -999 -99

11 Burrowing owl -999 0.01 0.09 -999 -999 0 -999 -999 -999 -999 -999 -999 -999 -999 -999 -9912 Canada goose -999 0 -999 -999 -999 -999 -999 -999 -999 -999 -999 -999 0.2 0.2 0 0

13 Cerulean warbler -999 0.95 -999 -999 -999 -999 -999 -999 -999 -999 -999 -999 -999 -999 -999 -9914 Cooper's hawk -999 -999 0.15 -999 -999 0.29 -999 -999 -999 -999 -999 -999 -999 -999 -999 -9915 Coyote -999 0.01 0.05 0 0 0.03 -999 -999 -999 -999 0.05 -999 -999 -999 -999 -9916 Deer mouse -999 0.07 -999 -999 -999 -999 -999 -999 -999 -999 0.01 0 0 0.12 -999 -9917 Eastern box turtle 0.03 0.08 0 -999 -999 -999 -999 -999 -999 -999 0.05 0 0.13 -999 -999 -9918 Eastern cottontail -999 -999 -999 -999 -999 -999 -999 -999 -999 -999 -999 -999 0.17 -999 -999 22 Great Basin pocket mouse -999 0.2 -999 -999 -999 -999 -999 -999 -999 -999 -999 -999 0 0.2 -999 -99

23 Great blue heron -999 0.02 0.03 -999 -999 0 -999 -999 -999 -999 -999 -999 0.01 -999 -999 -99

25 Green heron 0 0.01 0 -999 -999 -999 -999 -999 -999 -999 -999 -999 0 -999 -999 -9926 Herring gull 0 0.1 0.05 -999 -999 0.01 -999 -999 -999 -999 0 -999 0 -999 -999 -9927 Kit fox -999 0 0.25 0.2 0.2 0 -999 -999 -999 -999 0 -999 0 -999 -999 -99
12-34

Worms

Other invertebrates

Small mammals

Herbivorous vertebrates

Omnivorous vertebrates

Small birds

Benthic filter feeders

T3 Fish

T4 Fish

Aquatic plants

Exposed fruits

Exposed vegetables

Forage

Grains

Roots

Silage

Table 12B-1a. (continued)

28 Least weasel -999 0 0.5 -999 -999 0 -999 -999 -999 -999 -999 -999 -999 -999 -999 -9929 Lesser scaup -999 0.1 -999 -999 -999 -999 -999 -999 -999 -999 0 -999 0 0.1 -999 -9930 Little brown bat -999 0.95 -999 -999 -999 -999 -999 -999 -999 -999 -999 -999 -999 -999 -999 -9931 Loggerhead shrike -999 0.24 0.28 -999 -999 0.28 -999 -999 -999 -999 -999 -999 -999 -999 -999 -9932 Long-tailed weasel 0 0 0.14 0 0 0 -999 -999 -999 -999 -999 -999 -999 -999 -999 -9933 Mallard duck -999 0.1 -999 -999 -999 -999 -999 -999 -999 -999 0 -999 0 0.5 0 34 Marsh wren -999 0.95 -999 -999 -999 -999 -999 -999 -999 -999 -999 -999 -999 -999 -999 -9935 Meadow vole -999 0.01 -999 -999 -999 -999 -999 -999 -999 -999 0.01 0 0.5 0 0.01 36 Mink -999 0 0.1 0.1 -999 0 -999 -999 -999 -999 -999 -999 -999 -999 -999 -9937 Mule deer -999 -999 -999 -999 -999 -999 -999 -999 -999 -999 0.1 0 0.5 0 -999 38 Muskrat -999 -999 -999 -999 -999 -999 -999 -999 -999 -999 -999 0 0.02 0 0 -9939 Northern bobwhite -999 0 -999 -999 -999 -999 -999 -999 -999 -999 0 -999 0 0.21 -999 -9940 Northern water snake -999 0 0 -999 -999 -999 -999 -999 -999 -999 -999 -999 -999 -999 -999 -9941 Osprey -999 -999 0 -999 -999 0 -999 -999 -999 -999 -999 -999 -999 -999 -999 -9942 Painted turtle -999 0 -999 -999 -999 -999 -999 -999 -999 -999 -999 -999 -999 -999 -999 -9943 Pine vole -999 0 -999 -999 -999 -999 -999 -999 -999 -999 0 0 0.25 0 0.25 -9944 Prairie vole -999 0 -999 -999 -999 -999 -999 -999 -999 -999 0 0 0.5 0 0.1 -9945 Raccoon 0 0 0 -999 -999 0 -999 -999 -999 -999 0.25 -999 0.1 0 0 46 Racer -999 0.1 0.1 -999 -999 0 -999 -999 -999 -999 -999 -999 -999 -999 -999 -9947 Red fox -999 0 0.1 0 0 0 -999 -999 -999 -999 0.1 -999 0 -999 -999 -9948 Red-tailed hawk 0 0 0.1 0 0 0 -999 -999 -999 -999 -999 -999 -999 -999 -999 -9949 River otter -999 0 0 -999 -999 0 -999 -999 -999 -999 -999 -999 -999 -999 -999 -9950 Short-tailed shrew 0.25 0.1 0 -999 -999 -999 -999 -999 -999 -999 0 0 -999 -999 -999 -9951 Short-tailed weasel -999 0 0.5 -999 -999 0 -999 -999 -999 -999 -999 -999 -999 -999 -999 -9952 Snapping turtle 0 0.1 0 -999 -999 0 -999 -999 -999 -999 -999 -999 -999 -999 -999 -9953 Southern hognose snake -999 -999 0 -999 -999 -999 -999 -999 -999 -999 -999 -999 -999 -999 -999 -99
12-35

Worms

Other invertebrates

Small mammals

Herbivorous vertebrates

Omnivorous vertebrates

Small birds

Benthic filter feeders

T3 Fish

T4 Fish

Aquatic plants

Exposed fruits

Exposed vegetables

Forage

Grains

Roots

Silage

Table 12B-1a. (continued)

54 Spotted sandpiper -999 0.5 -999 -999 -999 -999 -999 -999 -999 -999 -999 -999 -999 -999 -999 -9955 Tree swallow -999 0.5 -999 -999 -999 -999 -999 -999 -999 -999 0 -999 0 -999 -999 -9956 Western meadowlark -999 0.5 -999 -999 -999 -999 -999 -999 -999 -999 -999 -999 -999 0 -999 -9957 White-tailed deer -999 -999 -999 -999 -999 -999 -999 -999 -999 -999 0.1 0 0.5 0 -999 

 -999 denotes a null value. The species does not consume the particular receptor.
12-36

Table 12B-1b. Minimum Prey Preferences in Waterbody Margin and Wetland Margin Habitats (p

Worms

Other Invertebrates

Small Mammals

Herbivorous Vertebrates

Omnivorous Vertebrates

Small Birds

Benthic Filter Feeders

T3 Fish

T4 Fish

Aquatic Plants

Exposed Fruits

Exposed Vegetables

Forage

Grains

Roots

Silage

Numprey 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 

Numreceptor

1 Alligator Snapping Turtle -999 0 0 -999 -999 -999 0.2 0.2 0.2 0 0 -999 -999 -999 -999 -9

2 American Kestrel 0 0.25 0 -999 -999 0 -999 -999 -999 -999 -999 -999 -999 -999 -999 -93 American Robin 0.15 0.08 -999 -999 -999 -999 -999 -999 -999 -999 0.07 -999 0 -999 -999 -94 American Woodcock 0.6 0.01 -999 -999 -999 -999 -999 -999 -999 -999 -999 -999 0 -999 -999 -95 Bald Eagle -999 0 0.1 0 0 0.02 -999 0.25 0.25 -999 -999 -999 -999 -999 -999 -96 Beaver -999 -999 -999 -999 -999 -999 -999 -999 -999 0.1 -999 -999 0.2 -999 0.01 -97 Belted Kingfisher -999 0.2 0 -999 -999 -999 0 0.5 -999 -999 -999 -999 0 -999 -999 -98 Black Bear -999 0.3 0.01 0 0 -999 0 0 0 -999 0.3 0 0.05 -999 0 9 Black-Tailed Jack Rabbit -999 -999 -999 -999 -999 -999 -999 -999 -999 -999 -999 -999 0.9 -999 -999 -9

11 Burrowing Owl -999 0.01 0.09 -999 -999 0 -999 -999 -999 -999 -999 -999 -999 -999 -999 -912 Canada Goose -999 0 -999 -999 -999 -999 -999 -999 -999 0 -999 -999 0.2 0.2 0 013 Cerulean Warbler -999 0.95 -999 -999 -999 -999 -999 -999 -999 -999 -999 -999 -999 -999 -999 -914 Cooper's Hawk -999 -999 0.15 -999 -999 0.29 -999 -999 -999 -999 -999 -999 -999 -999 -999 -915 Coyote -999 0.01 0.05 0 0 0.03 -999 -999 -999 -999 0.05 -999 -999 -999 -999 -916 Deer Mouse -999 0.07 -999 -999 -999 -999 -999 -999 -999 -999 0.01 0 0 0.12 -999 -917 Eastern Box Turtle 0.03 0.08 0 -999 -999 -999 -999 -999 -999 -999 0.05 0 0.13 -999 -999 -918 Eastern Cotton Tail -999 -999 -999 -999 -999 -999 -999 -999 -999 -999 -999 -999 0.17 -999 -999 22 Great Basin Pocket Mouse -999 0.2 -999 -999 -999 -999 -999 -999 -999 -999 -999 -999 0 0.2 -999 -923 Great Blue Heron -999 0.02 0.03 -999 -999 0 0 0.05 0.05 0.01 -999 -999 0.01 -999 -999 -925 Green Heron 0 0.01 0 -999 -999 -999 -999 0.4 -999 0 -999 -999 0 -999 -999 -926 Herring Gull 0 0.1 0.05 -999 -999 0.01 0.1 0.05 0.05 0 0 -999 0 -999 -999 -927 Kit Fox -999 0 0.25 0.2 0.2 0 -999 -999 -999 -999 0 -999 0 -999 -999 -928 Least Weasel -999 0 0.5 -999 -999 0 -999 -999 -999 -999 -999 -999 -999 -999 -999 -9
12-37

Worms

Other Invertebrates

Small Mammals

Herbivorous Vertebrates

Omnivorous Vertebrates

Small Birds

Benthic Filter Feeders

T3 Fish

T4 Fish

Aquatic Plants

Exposed Fruits

Exposed Vegetables

Forage

Grains

Roots

Silage

Table 12B-1b. (continued)

29 Lesser Scaup -999 0.1 -999 -999 -999 -999 0 -999 -999 0 0 -999 0 0.1 -999 -930 Little Brown Bat -999 0.95 -999 -999 -999 -999 -999 -999 -999 -999 -999 -999 -999 -999 -999 -9

31 Loggerhead Shrike -999 0.24 0.28 -999 -999 0.28 -999 -999 -999 -999 -999 -999 -999 -999 -999 -932 Long-Tailed Weasel 0 0 0.14 0 0 0 -999 -999 -999 -999 -999 -999 -999 -999 -999 -933 Mallard Duck -999 0.1 -999 -999 -999 -999 0 0 -999 0 0 -999 0 0.5 0 34 Marsh Wren -999 0.95 -999 -999 -999 -999 0 -999 -999 -999 -999 -999 -999 -999 -999 -935 Meadow Vole -999 0.01 -999 -999 -999 -999 -999 -999 -999 -999 0.01 0 0.5 0 0.01 36 Mink -999 0 0.1 0.1 -999 0 -999 0 0 -999 -999 -999 -999 -999 -999 -937 Mule Deer -999 -999 -999 -999 -999 -999 -999 -999 -999 -999 0.1 0 0.5 0 -999 38 Muskrat -999 -999 -999 -999 -999 -999 0 0 -999 0.12 -999 0 0.02 0 0 -939 Northern Bobwhite -999 0 -999 -999 -999 -999 -999 -999 -999 -999 0 -999 0 0.21 -999 -940 Northern Water Snake -999 0 0 -999 -999 -999 0 0.5 0.3 -999 -999 -999 -999 -999 -999 -941 Osprey -999 -999 0 -999 -999 0 -999 0.25 0.25 -999 -999 -999 -999 -999 -999 -942 Painted Turtle -999 0 -999 -999 -999 -999 -999 0 -999 0.5 -999 -999 -999 -999 -999 -943 Pine Vole -999 0 -999 -999 -999 -999 -999 -999 -999 -999 0 0 0.25 0 0.25 -944 Prairie Vole -999 0 -999 -999 -999 -999 -999 -999 -999 -999 0 0 0.5 0 0.1 -945 Raccoon 0 0 0 -999 -999 0 0 0 0 -999 0.25 -999 0.1 0 0 46 Racer -999 0.1 0.1 -999 -999 0 -999 -999 -999 -999 -999 -999 -999 -999 -999 -9

47 Red Fox -999 0 0.1 0 0 0 -999 -999 -999 -999 0.1 -999 0 -999 -999 -948 Red-Tailed Hawk 0 0 0.1 0 0 0 -999 -999 -999 -999 -999 -999 -999 -999 -999 -949 River Otter -999 0 0 -999 -999 0 0 0.25 0.25 -999 -999 -999 -999 -999 -999 -950 Short-Tailed Shrew 0.25 0.1 0 -999 -999 -999 -999 -999 -999 -999 0 0 -999 -999 -999 -951 Short-Tailed Weasel -999 0 0.5 -999 -999 0 -999 -999 -999 -999 -999 -999 -999 -999 -999 -952 Snapping Turtle 0 0.1 0 -999 -999 0 0.1 0.1 0.1 0.1 -999 -999 -999 -999 -999 -953 Southern Hognose Snake -999 -999 0 -999 -999 -999 -999 -999 -999 -999 -999 -999 -999 -999 -999 -9
12-38

Worms

Other Invertebrates

Small Mammals

Herbivorous Vertebrates

Omnivorous Vertebrates

Small Birds

Benthic Filter Feeders

T3 Fish

T4 Fish

Aquatic Plants

Exposed Fruits

Exposed Vegetables

Forage

Grains

Roots

Silage

Table 12B-1b. (continued)

54 Spotted Sandpiper -999 0.5 -999 -999 -999 -999 0 0 -999 -999 -999 -999 -999 -999 -999 -955 Tree Swallow -999 0.5 -999 -999 -999 -999 -999 -999 -999 -999 0 -999 0 -999 -999 -956 Western Meadow Lark -999 0.5 -999 -999 -999 -999 -999 -999 -999 -999 -999 -999 -999 0 -999 -957 White-Tailed Deer -999 -999 -999 -999 -999 -999 -999 -999 -999 0 0.1 0 0.5 0 -999 

-999 denotes a null value. The species does not consume the particular receptor.
12-39

Table 12B-2a. Maximum Prey Preferences in Terrestrial Habitats (percent of diet)

Worms

Other Invertebrates

Small Mammals

Herbivorous Vertebrates

Omnivorous Vertebrates

Small Birds

Benthic Filter Feeders

T3 Fish

T4 Fish

Aquatic Plants

Exposed Fruits

Exposed Vegetables

Forage

Grains

Roots

Numprey 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 

Numreceptor

1 Alligator snapping turtle 0 0.1 0.1 0 0 0 0 0 0 0 0.2 0 0 0 0 2 American kestrel 0.05 0.51 0.51 0 0 0.3 0 0 0 0 0 0 0 0 0 3 American robin 0.27 0.93 0 0 0 0 0 0 0 0 0.92 0 0.24 0 0 4 American woodcock 1 0.16 0 0 0 0 0 0 0 0 0 0 0.11 0 0 5 Bald eagle 0 0.1 0.34 0.34 0.34 0.53 0 0 0 0 0 0 0 0 0 6 Beaver 0 0 0 0 0 0 0 0 0 0 0 0 0.9 0 0.1 7 Belted kingfisher 0 0.71 0.1 0 0 0 0 0 0 0 0 0 0.1 0 0 8 Black bear 0 0.5 0.1 0.1 0.1 0 0 0 0 0 0.5 0.1 0.3 0 0.05 9 Black-tailed jack rabbit 0 0 0 0 0 0 0 0 0 0 0 0 1 0 0 

11 Burrowing owl 0 0.9 0.68 0 0 0.1 0 0 0 0 0 0 0 0 0 12 Canada goose 0 0.1 0 0 0 0 0 0 0 0 0 0 1 1 0.37 

13 Cerulean warbler 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 14 Cooper's hawk 0 0 0.71 0 0 0.85 0 0 0 0 0 0 0 0 0 15 Coyote 0 0.1 0.73 0.2 0.2 0.28 0 0 0 0 0.2 0 0 0 0 16 Deer mouse 0 0.58 0 0 0 0 0 0 0 0 0.46 0.1 0.41 0.65 0 17 Eastern box turtle 0.6 0.22 0.1 0 0 0 0 0 0 0 0.33 0.1 0.39 0 0 18 Eastern cotton tail 0 0 0 0 0 0 0 0 0 0 0 0 1 0 0 22 Great basin pocket mouse 0 0.25 0 0 0 0 0 0 0 0 0 0 0.14 0.85 0 23 Great blue heron 0 0.09 0.23 0 0 0.02 0 0 0 0 0 0 0.63 0 0 25 Green heron 0.21 0.84 0.05 0 0 0 0 0 0 0 0 0 0.03 0 0 26 Herring gull 0.1 0.38 0.78 0 0 0.3 0 0 0 0 0.1 0 0.16 0 0 
12-40

Worms

Other Invertebrates

Small Mammals

Herbivorous Vertebrates

Omnivorous Vertebrates

Small Birds

Benthic Filter Feeders

T3 Fish

T4 Fish

Aquatic Plants

Exposed Fruits

Exposed Vegetables

Forage

Grains

Roots

Table 12B-2a. (continued)

27 Kit fox 0 0.1 0.94 0.94 0.94 0.1 0 0 0 0 0.1 0 0.1 0 0 28 Least weasel 0 0.1 1 0 0 0.1 0 0 0 0 0 0 0 0 0 29 Lesser scaup 0 0.69 0 0 0 0 0 0 0 0 0.1 0 0.1 1 0 30 Little brown bat 0 1.2000000000000031 Loggerhead shrike 0 0.96 0.76 0 0 0.76 0 0 0 0 0 0 0 0 0 32 Long-tailed weasel 0.1 0.1 0.82 0.25 0.25 0.25 0 0 0 0 0 0 0 0 0 33 Mallard duck 0 0.6 0 0 0 0 0 0 0 0 0.24 0 0.1 1 0.1 34 Marsh wren 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 35 Meadow vole 0 0.05 0 0 0 0 0 0 0 0 0.2 0.1 1 0.25 0.34 36 Mink 0 0.63 0.43 0.43 0 0.33 0 0 0 0 0 0 0 0 0 37 Mule deer 0 0 0 0 0 0 0 0 0 0 0.25 0.6 0.94 0.1 0 38 Muskrat 0 0 0 0 0 0 0 0 0 0 0 0.1 0.81 0.1 0.1 39 Northern bobwhite 0 0.36 0 0 0 0 0 0 0 0 0.25 0 0.25 0.92 0 40 Northern water snake 0 0.25 0.12 0 0 0 0 0 0 0 0 0 0 0 0 41 Osprey 0 0 1 0 0 0.1 0 0 0 0 0 0 0 0 0 42 Painted turtle 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 43 Pine vole 0 0.1 0 0 0 0 0 0 0 0 0.1 0.1 0.96 0.21 0.5 44 Prairie vole 0 0.25 0 0 0 0 0 0 0 0 0.25 0.1 1 0.25 0.25 45 Raccoon 0.1 0.9 0.35 0 0 0.19 0 0 0 0 0.86 0 0.66 0.1 0.1 46 Racer 0 0.64 0.62 0 0 0.08 0 0 0 0 0 0 0 0 0 47 Red fox 0 0.25 0.92 0.1 0.1 0.46 0 0 0 0 0.5 0 0.1 0 0 48 Red-tailed hawk 0.1 0.25 0.9 0.25 0.25 0.25 0 0 0 0 0 0 0 0 0 49 River otter 0 0.25 0.25 0 0 0.25 0 0 0 0 0 0 0 0 0 50 Short-tailed shrew 0.5 0.5 0.1 0 0 0 0 0 0 0 0.1 0.25 0 0 0 51 Short-tailed weasel 0 0.25 0.8 0 0 0.25 0 0 0 0 0 0 0 0 0 
12-41

Worms

Other Invertebrates

Small Mammals

Herbivorous Vertebrates

Omnivorous Vertebrates

Small Birds

Benthic Filter Feeders

T3 Fish

T4 Fish

Aquatic Plants

Exposed Fruits

Exposed Vegetables

Forage

Grains

Roots

Table 12B-2a. (continued)

52 Snapping turtle 0.1 0.25 0.25 0 0 0.1 0 0 0 0 0 0 0 0 0 53 Southern hognose snake 0 0 0.25 0 0 0 0 0 0 0 0 0 0 0 0 54 Spotted sandpiper 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 55 Tree swallow 0 0.78 0 0 0 0 0 0 0 0 0.25 0 0.25 0 0 56 Western meadow lark 0 1 0 0 0 0 0 0 0 0 0 0 0 0.25 0 57 White-tailed deer 0 0 0 0 0 0 0 0 0 0 0.4 0.25 1 0.78 0 

Shaded values are not real values; they were entered to make the sum of the MaxPreyPref greater than1. 

The species for which these values were entered do not occur in these (terrestrial) habitats, and were used as placeholders in this table. The little brown bat does occur in t

prey item (invertebrates). 0 denotes a null value. The species does not consume the particular prey item.
12-42

Table 12B-2b. Maximum Prey Preferences in Waterbody Margin and Wetland Margin Habitats (p

Worms

Other Invertebrates

Small Mammals

Herbivorous Vertebrates

Omnivorous Vertebrates

Small Birds

Benthic Filter Feeders

T3 Fish

T4 Fish

Aquatic Plants

Exposed Fruits

Exposed Vegetables

Forage

Grains

Roots

Sil

Numprey 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 1

Numreceptor

1 Alligator snapping turtle 0 0.1 0.1 0 0 0 0.6 0.6 0.6 0.2 0.2 0 0 0 0 2 American kestrel 0.05 0.51 0.51 0 0 0.3 0 0 0 0 0 0 0 0 0 3 American robin 0.27 0.93 0 0 0 0 0 0 0 0 0.92 0 0.24 0 0 4 American woodcock 1 0.16 0 0 0 0 0 0 0 0 0 0 0.11 0 0 5 Bald eagle 0 0.1 0.34 0.34 0.34 0.53 0 0.74 0.74 0 0 0 0 0 0 6 Beaver 0 0 0 0 0 0 0 0 0 0.9 0 0 0.9 0 0.1 7 Belted kingfisher 0 0.41 0.1 0 0 0 0.1 1 0 0 0 0 0.1 0 0 8 Black bear 0 0.5 0.1 0.1 0.1 0 0.05 0.3 0.3 0 0.5 0.1 0.3 0 0.05 09 Black-tailed jackrabbit 0 0 0 0 0 0 0 0 0 0 0 0 1 0 0 

11 Burrowing owl 0 0.9 0.68 0 0 0.1 0 0 0 0 0 0 0 0 0 12 Canada goose 0 0.1 0 0 0 0 0 0 0 0.2 0 0 1 1 0.37 

13 Cerulean warbler 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 14 Cooper's hawk 0 0 0.71 0 0 0.85 0 0 0 0 0 0 0 0 0 15 Coyote 0 0.1 0.73 0.2 0.2 0.28 0 0 0 0 0.2 0 0 0 0 16 Deer mouse 0 0.58 0 0 0 0 0 0 0 0 0.46 0.1 0.41 0.65 0 17 Eastern box turtle 0.6 0.22 0.1 0 0 0 0 0 0 0 0.33 0.1 0.39 0 0 18 Eastern cottontail rabbit 0 0 0 0 0 0 0 0 0 0 0 0 1 0 0 022 Great basin pocket mouse 0 0.25 0 0 0 0 0 0 0 0 0 0 0.14 0.85 0 23 Great blue heron 0 0.09 0.23 0 0 0.02 0.09 0.98 0.98 0.33 0 0 0.33 0 0 
12-43

Worms

Other Invertebrates

Small Mammals

Herbivorous Vertebrates

Omnivorous Vertebrates

Small Birds

Benthic Filter Feeders

T3 Fish

T4 Fish

Aquatic Plants

Exposed Fruits

Exposed Vegetables

Forage

Grains

Roots

Sil

Table 12B-2b. (continued)

25 Green heron 0.21 0.24 0.05 0 0 0 0 0.9 0 0.03 0 0 0.03 0 0 26 Herring gull 0.1 0.38 0.78 0 0 0.3 0.38 0.73 0.73 0.16 0.1 0 0.16 0 0 27 Kit fox 0 0.1 0.94 0.94 0.94 0.1 0 0 0 0 0.1 0 0.1 0 0 28 Least weasel 0 0.1 1 0 0 0.1 0 0 0 0 0 0 0 0 0 29 Lesser scaup 0 0.69 0 0 0 0 0.25 0 0 0.1 0.1 0 0.1 1 0 30 Little brown bat 0 1000000000000031 Loggerhead shrike 0 0.96 0.76 0 0 0.76 0 0 0 0 0 0 0 0 0 32 Long-tailed weasel 0.1 0.1 0.82 0.25 0.25 0.25 0 0 0 0 0 0 0 0 0 33 Mallard duck 0 0.6 0 0 0 0 0.1 0.1 0 0.1 0.24 0 0.1 1 0.1 034 Marsh wren 0 1 0 0 0 0 0.05 0 0 0 0 0 0 0 0 35 Meadow vole 0 0.05 0 0 0 0 0 0 0 0 0.2 0.1 1 0.25 0.34 036 Mink 0 0.63 0.43 0.43 0 0.33 0 0.9 0.9 0 0 0 0 0 0 37 Mule deer 0 0 0 0 0 0 0 0 0 0 0.25 0.6 0.94 0.1 0 38 Muskrat 0 0 0 0 0 0 0.5 0.1 0 0.91 0 0.1 0.81 0.1 0.1 39 Northern bobwhite 0 0.36 0 0 0 0 0 0 0 0 0.25 0 0.25 0.92 0 40 Northern water snake 0 0.25 0.12 0 0 0 0.05 0.75 0.5 0 0 0 0 0 0 41 Osprey 0 0 0.05 0 0 0.1 0 1 1 0 0 0 0 0 0 42 Painted turtle 0 0.25 0 0 0 0 0 0.13 0 1 0 0 0 0 0 43 Pine vole 0 0.1 0 0 0 0 0 0 0 0 0.1 0.1 0.96 0.21 0.5 44 Prairie vole 0 0.25 0 0 0 0 0 0 0 0 0.25 0.1 1 0.25 0.25 45 Raccoon 0.1 0.9 0.35 0 0 0.19 0.25 0.23 0.23 0 0.86 0 0.66 0.1 0.1 46 Racer 0 0.64 0.62 0 0 0.08 0 0 0 0 0 0 0 0 0 47 Red fox 0 0.25 0.92 0.1 0.1 0.46 0 0 0 0 0.5 0 0.1 0 0 48 Red-tailed hawk 0.1 0.25 0.9 0.25 0.25 0.25 0 0 0 0 0 0 0 0 0 
12-44

Worms

Other Invertebrates

Small Mammals

Herbivorous Vertebrates

Omnivorous Vertebrates

Small Birds

Benthic Filter Feeders

T3 Fish

T4 Fish

Aquatic Plants

Exposed Fruits

Exposed Vegetables

Forage

Grains

Roots

Sil

Table 12B-2b. (continued)

49 River otter 0 0.25 0.25 0 0 0.25 0.1 0.94 0.94 0 0 0 0 0 0 50 Short-tailed shrew 0.5 0.5 0.1 0 0 0 0 0 0 0 0.1 0.25 0 0 0 51 Short-tailed weasel 0 0.25 0.8 0 0 0.25 0 0 0 0 0 0 0 0 0 52 Snapping turtle 0.1 0.25 0.25 0 0 0.1 0.25 0.84 0.84 0.25 0 0 0 0 0 53 Southern hognose snake 0 0 0.25 0 0 0 0 0 0 0 0 0 0 0 0 54 Spotted sandpiper 0 1 0 0 0 0 0.25 0.25 0 0 0 0 0 0 0 55 Tree swallow 0 0.78 0 0 0 0 0 0 0 0 0.25 0 0.25 0 0 56 Western meadowlark 0 1 0 0 0 0 0 0 0 0 0 0 0 0.25 0 57 White-tailed deer 0 0 0 0 0 0 0 0 0 0.25 0.4 0.25 1 0.78 0 0

* 0 denotes a null value. The species does not consume the particular prey item.
Appendix 12C Home Range Parameters for Ecological Receptors

12-45

Appendix 12C

Home Range Parameters for Ecological

Receptors

Table 12C-1. Receptor Home Ranges and Bins . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12-47
Appendix 12C Home Range Parameters for Ecological Receptors

12-46

This page intentionally left blank
Appendix 12C Home Range Parameters for Ecological Receptors 

12-47

Table 12C-1. Receptor Home Ranges and Bins

Receptor Index Receptor Species

Home Range (min)

m2

Home Range

(max)m2

Home Range

(midpt) m2

Bin 1 :hr =/<100,000 m2

19 Eastern newt 28 153 91

20 Flatwood slamander 100 100 100

21 Gopher frog1 7 200 104

24 Green frog 7 200 104

10 Bullfrog 1 400 201

35 Meadow vole 2 830 416

44 Prairie vole 73 980 527

16 Deer mouse 140 1,280 710

38 Muskrat 480 1,700 1,090

34 Marsh wren 156 2,600 1,378

54 Spotted sandpiper 2,500 2,500 2,500

30 Little brown bat 2,549 2,549 2,549

3 American robin 1,100 8,400 4,750

28 Least weasel 8,000 8,000 8,000

50 Short-tailed shrew 300 18,000 9,150

22 Great basin pocket mouse 500 24,000 12,250

40 Northern water snake1 18,000 30,000 24,000

53 Southern hognose snake1 18,000 30,000 24,000

46 Racer 18,000 30,000 24,000

17 Eastern box turtle 4,600 52,000 28,300

43 Pine vole 310 68,800 34,555

18 Eastern cottontail rabbit 8,000 78,000 43,000

42 Painted turtle2 2,400 83,800 43,100

52 Snapping turtle 2,400 83,800 43,100

7 Belted kingfisher3 6,000 84,000 45,000

25 Green heron3 6,000 84,000 45,000

31 Loggerhead shrike3 6,000 84,000 45,000

23 Great blue heron 6,000 84,000 45,000

56 Western meadowlark 12,000 130,000 71,000

Bin 2: hr >100,000 and <1 million m2

39 Northern bobwhite 36,000 186,000 111,000

51 Short-tailed weasel 20,000 250,000 135,000

6 Beaver 164,084 164,084 164,084

9 Black-tailed jackrabbit 162,000 202,000 182,000

13 Cerulean warbler4 20,000 600,000 310,000

55 Tree swallow 20,000 600,000 310,000

(continued)
Table 12C-1. (continued)

Appendix 12C Home Range Parameters for Ecological Receptors 

Receptor Index Receptor Species

Home Range (min)

m2

Home Range

(max)m2

Home Range

(midpt) m2

12-48

32 Long-tailed weasel 50,000 1,210,000 630,000

4 American woodcock 3,000 1,712,000 857,500

29 Lesser scaup 890,000 890,000 890,000

Bin 3: hr = or >1 million and <10 million m2

11 Burrowing owl 400 4,810,000 2,405,200

2 American kestrel 97,000 5,000,000 2,548,500

57 White-tailed deer 590,000 8,040,000 4,315,000

33 Mallard duck 380,000 14,400,000 7,390,000

27 Kit fox 2,600,000 13,700,000 8,150,000

14 Cooper's hawk 180,000 18,000,000 9,090,000

Bin 4: hr >10 million m2

37 Mule deer 1,286,800 21,227,200 11,257,000

48 Red-tailed hawk 600,000 24,650,000 12,625,000

47 Red fox 570,000 34,200,000 17,385,000

26 Herring gull5 18,300,000 18,800,000 18,550,000

41 Osprey5 18,300,000 18,800,000 18,550,000

5 Bald eagle 18,300,000 18,800,000 18,550,000

1 Alligator snapping turtle 180,000 38,480,000 19,330,000

45 Raccoon 53,000 49,460,000 24,756,500

36 Mink 78,000 78,540,000 39,309,000

15 Coyote 14,300,000 68,000,000 41,150,000

8 Black bear 79 177,000,000 88,500,040

12 Canada goose 1,800,000 1,029,220,000 515,510,000

49 River otter 2,950,000 19,113,450,000 9,558,200,000

1

 no data available. Home range data for the racer used.

2

 no data available. Home range data for the snapping turtle used. 3

 no data available. Home range data for the great blue heron used.

4

 no data available. Home range data for the tree swallow used.

5

 no data available. Home range data for the bald eagle used.