 |
Iowa Small Mammal
Project
Data compiled by John Bowles
Web site and data processing by John Bowles and David Dobson
© 2006-2009 |
Abstract
We present a data set of approximately
12,000 records of small mammals collected in Iowa between 1972 and 1993.
When possible, the records include species, coordinates of observation
or capture, gender, reproductive status and data, standard measurements
(Hall 1962) and other identifiable characteristics. We also include
habitat information and GIS data and maps for download.
Recommended Citation
Bowles, J.B., D.M. Dobson, and R.P.
Lampe, 2009. Iowa small mammal database (online data archive),
http://www.guilford.edu/geology/iowamammals
Introduction
Flora and fauna data collecting is sporadic and depends largely on
the interests of local individuals and institutions. Our work in Iowa
began in the 1970’s when Bowles joined the Central College faculty in
Pella, Iowa. Lampe started his work in 1976 at Buena Vista College (now
university).

Figure 1. This figure
shows all small mammals observed and identified by Bowles and Lampe
(or their trained students) from 1972 to 1993. Included are
specimens given to us by others from Iowa for identification.
Our activity peaked in the late
1970s and early 1980s when general interest in the State’s natural
history increased. That interest was fueled by generation of Federal and
State Endangered Species lists, Earth Day I, formation of the Iowa
Natural History Association and its sponsorship both of symposia at Iowa
Academy of Science meetings and of annual forays to counties where data
were minimal or lacking. The first foray was to Fremont County in 1977
(Bowles 1977, Roosa 1977). Perhaps the most significant factor
increasing interest in Iowa’s natural history, however, was the
leadership of Dean M. Roosa, then naturalist for the Iowa Preserves
Board.

Figure 2. Map of sampling
sites for small mammals recorded by Bowles or Lampe (or their
trained students) from 1972 to 1993. Note: In order to show
sampling density in heavily sampled areas of this map, locations of
samples were randomly spread out by up to 10 km from their actual
locations.
Purposes
Our primary purposes for developing this website are to: 1) make our
data available to anyone seeking biological and ecological information
about Iowa’s small mammals, 2) provide our capture locality points in
GIS format, useful for generating maps showing overall distribution when
combined with other information (see cautionary note below) 3) provide
information that any teacher can use in developing class exercises using
real data. Cautionary note: Distribution maps generated with our data
alone simply show where we collected. To gain a more complete
understanding of past and present patterns of distribution, it is
imperative that researchers both consult the literature for past records
and conduct their own field studies. Furthermore, care must be exercised
when using our data since collecting methods varied according to the
needs of our particular studies (e.g., live-traps, pit traps,
snap-traps). Additional
information about collecting sites and methods is in John Bowles’ field
notes housed in the Museum of Natural History, University of Iowa, Iowa
City.
Sorting
Keys
The dataset can be filtered based on a number
of parameters, including:
You may also download the entire data set in Excel
format by clicking here.
Explanatory notes
Data are presented in table form with one animal per
row. For each record, a variety of data is presented. The
species are listed by codes with two letters for genus and two letters
for species as listed in Table 1. See
Table 2 for descriptions of the data types (columns of the data set).
The abbreviation NR (No Record) indicates that the data type was not recorded, and NA
indicates Not Applicable (e.g. male reproductive measurements
on female specimens, forearm and metacarpal measurements for non-bat
specimens).
Table 1. Species listing
Code |
Name |
Common names |
EPFU |
Eptesicus fuscus |
Big brown bat |
LABO |
Lasiurus borealis |
Red bat |
LACI |
Lasiurus cinereus |
Hoary bat |
LANO |
Lasionycterus noctivagans |
Silver-haired bat |
MYLU |
Myotis lucifugus |
Little brown bat |
MYSE |
Myotis septentrionalis |
Northern big-eared bat |
MYSO |
Myotis sodalis |
Indiana bat |
NYHU |
Nycticeius humeralis |
Evening bat |
PISU |
Pipistrellus subflavus |
Eastern pipstrelle bat |
BLBR |
Blarina brevicauda |
Northern short-tailed shrew |
BLHY |
Blarina hylophaga |
Elliot's short-tailed shrew |
CLGA |
Clethrionomys gapperi |
Red-backed vole |
CRPA |
Cryptotis parva |
Least shrew |
GEBU |
Geomys bursarius |
Plains pocket gopher |
MIOC |
Microtus ochrogaster |
Prairie vole |
MIPE |
Microtus pennsylvanicus |
Meadow vole |
MIPI |
Microtus pinetorum |
Woodland vole |
MUER |
Mustela erminea |
Ermine |
MUMU |
Mus musculus |
House mouse |
ONLE |
Onychomys leucogaster |
Northern grasshopper mouse |
PEFL |
Perognathus flavescens |
Plains pocket mouse |
PELE |
Peromyscus leucopus |
White-footed mouse |
PEMA |
Peromyscus maniculatus |
Deer mouse |
RANO |
Rattus norvegicus |
Norway rat |
REME |
Reithrodontomys megalotis |
Western harvest mouse |
SCAQ |
Scalopus aquaticus |
Eastern mole |
SOCI |
Sorex cinereus and/or Sorex haydeni* |
Masked shrew and Hayden's shrew |
SYCO |
Synaptomys cooperi |
Southern bald lemming |
TAST |
Tamias striatus |
Eastern chipmunk |
ZAHU |
Zapus hudsonius |
Meadow jumping mouse |
* cannot distinguish without observation of skull (Whidden et
al., 200?) |
Table 2. Data types presented
Parameter |
Description |
Species |
Four-letter code for genus and species - See
Table 1) |
Year |
Year captured |
Month |
Month captured |
Day |
Day captured |
Date |
Full date of capture |
County |
County where captured (all in Iowa) |
X-coordinate |
UTM Zone 15, in meters (eastings) |
Y-coordinate |
UTM Zone 15, in meters (northings) |
HabitatCode |
One-letter code for habitat type (see Table 3
below) |
ReferenceCode |
Abbreviated reference code for study (see
Table 4 below) |
Age |
Developmental stage of specimen |
Sex |
Gender (male, female, unknown) |
CaptureMethod |
Method used for capture |
Specimen |
Disposition of capured specimen (released,
discarded, preserved, etc.) |
Total Length |
Total length in mm |
Tail Length |
Tail length in mm |
Hind Foot Length |
Hind foot length in mm |
Ear Length |
Ear length in mm |
Weight |
Weight in grams |
Molt |
Molt stage |
Forearm |
Forearm length in mm (bats only) |
MCIII |
Metacarpal III length (bats only) |
MCV |
Metacarpal V length (bats only) |
Male external |
External analysis of reproductive status |
TestisLength |
Testis length in mm (male only) |
TestisWidth |
Testis width in mm (male only) |
Epididymus |
Convolution status of epididymus tubules (male
only) |
SemVesicles |
Development of seminal vesicles (male only) |
Mammae |
Size and status of mammae (female only) |
TotalEmbryos |
Total embryos counted (female only) |
Embryo length |
Crown to rump in mm (female only) |
Pregnant |
Pregnancy status (female only) |
Table 3.
Habitat codes used
Code |
Habitat |
Description |
G |
Tallgrass prairie |
Native or reconstructed; includes pure or mixed stands of
switchgrass, big and little bluestem, Indian grass, and forbes
(native and/or introduced). |
P |
Pasture or Grassy field |
Introduced grasses: chiefly bluegrass, brome, or Reed's canary
grass; solid or mixed with clover and/or forbs/weeds; active or
abandoned (oldfield); upland, bottomland, fencerow, creekside,
or roadside ditch. |
D |
Deciduous woods |
Forest, woodlot, riparian, edge |
H |
Hayfield |
Alfalfa; usually with clover and/or sweet-clover |
R |
Railroad Rights of Way |
Active or abandoned; at least some grasses (native or
introduced, annual or perennial) |
C |
Cropland |
Active or idle corn, unspecified |
S |
Sand prairie |
Native grasses on sandy substrate, usually shorter than in other
prairie types |
L |
Lake shore |
Lake shore (chiefly Red Rock Lake, which is flood-controlled) |
W |
Cattails |
Cattail patch |
M |
Marsh |
Marsh or slough |
K |
Marijuana patch |
Patch of wild marijuana plants |
B |
Buildings |
In or under buildings or structures |
F |
Coniferous forest |
Evergreen woods, often pine trees |
U |
Cavern |
Underground space such as cave or mine (not merely a burrow) |
E |
Bridge |
Wooden bridge bat roost |
X |
Not recorded |
Not recorded, not classified, or impossible to determine from
description |
Maps and
Interpretation
We hope that the data set provided will offer opportunities for a
variety of different types of research. Below is an example of a
question that could be addressed - species breakdown between prairie and
forested areas.


GIS
Datasets
We plan to offer the data in GIS format in the future.
Sample
Exercises for Biology Classes
Here are some sample activities that could be completed
with the data provided. Some proficiency with Excel or other
database software might be helpful.
-
Compute size statistics -
Compare mean tail length distribution of
Peromyscus leucopus (PELE) with
Peromyscus maniculatus (PEMA) and forearm length of Eptesicus fuscus
(EPFU) with any of the Myotis species. Students can
use a T-test to show that the tail lengths are significantly
different, and devise a classification scheme based on the
means and standard deviations.
-
Determine likely mammal
population for a given habitat, e.g.
bluegrass field, using the habitat data provided.
-
Are jumping mice more
likely to give birth in the summer or the winter? Use the
reproductive statistics to ascertain reproductive patterns.
-
What species are likely
to be found along a recently flooded shoreline? This would
reflect which species are the first to invade a newly exposed
lakeshore.
-
Compare testes sizes at
different times of year (e.g. June vs. September) for any given
species. What percent of the population has reached sexual
maturity at these times of year? What does this indicate about
the reproductive cycle?
-
Using techniques like
those in previous exercises, compare reproductive cycles of
different species. Are there differences? Can they be
explained?
-
Are male
Peromyscus leucopus (PELE) more
likely to be caught in July or August? This is trickier than
it seems, because collecting rates were not necessarily identical
during the year. One technique would be to compare
percentages of PELE of all organisms sampled, and examine changes in
their relative proportion of the records. This can be compared
with the reproductive cycle and with the maturity of the captured
animals.
References
John Bowles produced a detailed study of Iowa mammals
for his dissertation. This covers the period prior to 1971, when
our data here begin. This work includes detailed distributional
records, which cannot be inferred from the data here, and a variety of
other maps and data sets. Please see:
Bowles, J.B., 1975. Distribution and
Biogeography of Mammals of Iowa, Special Publications of the Museum
of Texas Tech University No. 9, Texas Tech Press, Lubbock, 184 pp.
The first attempt at a comprehensive study of Iowa
mammals was Thomas G. Scott's work:
Scott, T.G., 1937. Mammals of Iowa. Iowa
State College Journal of Science 12:43-97.
Other articles referenced in the text above include:
Bowles, J.B., 1977. Update of mammals of Fremont
County, Iowa Bird Life, 47(4):138-147.
Bowles, J.B., 1992. History of mammal study in
Iowa, Jour. Iowa Acad. Sci 99(4):76-77.
Hall, E. R., 1962, Collecting and Preparing Study
Specimens of Small Vertebrates, Mus. of Nat. Hist.
Lampe, R.P., and J.B. Bowles, 1985. Annotated
checklist of the mammals of the Loess Hills of western Iowa. Proc.
Iowa Acad. Sci. 92(5):176-179.
Roosa, D.M., 1977. The first Iowa foray.
Iowa Bird Life, 47(4):119-123.
The following table shows the individual studies that
are included in the database. If they were published, the
appropriate journal reference is given.
Table 4. Reference codes
explained
Reference Code |
Explanation |
BrabandRR |
Specimens collected by L.A.
Braband in Story County in 1979. Unpublished Iowa State
University M.S. thesis: Braband, L.A. 1979,
Railroad right-of-ways as wildlife habitat. |
BrushyCreek1 |
Specimens collected by John
Bowles and Nixon Wilson in Webster County, 1978-1979.
Unpublished. |
BrushyCreek2 |
Specimens collected by Rick
Lampe and Nixon Wilson in Webster County, 1978-1979.
Unpublished. |
Clark79 |
Specimens collected in
western Iowa by Bryon Clark and John Bowles in Gleason-Hubel
Wildlife Area and Turin Loess Hills Preserve, 1979. Study
funded by Iowa Department of Natural Resources. Unpublished
internal report to DNR. |
ClarkBats |
Bat specimens collected by
Byron K. Clark, John Bowles, and Brenda S. Clark in 1982.
Published in Clark, B.K., J.B. Bowles, and B.S. Clark, 1987,
Summer status of the endangered Indiana Bat in Iowa, Am.
Midl. Nat. 118:32-39, and Clark, B.S., J.B. Bowles, and B.K.
Clark, 1987, Summer occurrence of the Indiana bat, Keen’s
myotis, evening bat, silver –haired bat and eastern pipistrelle
in Iowa, Proc. Iowa Acad. Sci 94:89-93.
|
CoalMine |
Specimens collected by Janet
Voight in or near Wilcox Wildlife Area, Marion County, and
Hull Wildlife Refuge, Mahaska County in 1976. Published in
Voight, J., and D.C. Glenn-Lewin, 1979, Stripmining,
Peromyscus and other small mammals in southern Iowa.
Proc. Iowa Acad. Sci. 86:133-136. |
Foray77 |
Annual foray, organized by
Iowa Dept. of Natural Resources. Fremont County. |
Foray78 |
Annual foray, organized by
Iowa Dept. of Natural Resources. Allamakee County. |
Foray80 |
Annual foray, organized by
Iowa Dept. of Natural Resources. |
Foray81 |
Annual foray, organized by
Iowa Dept. of Natural Resources. |
Foray82 |
Annual foray, organized by
Iowa Dept. of Natural Resources. |
Foray83 |
Annual foray, organized by
Iowa Dept. of Natural Resources. |
Foray85 |
Annual foray, organized by
Iowa Dept. of Natural Resources. |
Foray86 |
Annual foray, organized by
Iowa Dept. of Natural Resources. |
Foray88 |
Annual foray, organized by
Iowa Dept. of Natural Resources. |
Foray92 |
Annual foray, organized by
Iowa Dept. of Natural Resources. |
Foray93 |
Annual foray, organized by
Iowa Dept. of Natural Resources. |
Hays79 |
Specimens collected by Jerry
Choate et al., in southwestern Iowa in 1979. Unpublished. |
Heiser78 |
1978 Department of Natural
Resources study in western Iowa conducted by Neil Heiser.
Unpublished. |
Lampe1 |
|
Lampe2 |
|
LinnCo |
Specimens collected by Nixon
Wilson and John Bowles in Linn County in 1981. Unpublished. |
Lucas77-78 |
Specimens collected by
Pettinger family at Pettinger farm in Lucas County in 1977-78.
Unpublished. |
Pella |
Specimens collected by John
Bowles and students near Pella, IA, 1979-1985. Unpublished. |
Monona78-79 |
Specimens collected by John
Bowles and students in Monona County, Pella, IA, 1978-1979.
Unpublished. |
Ogrens74-80 |
Specimens collected by John
Bowles et al. at Ogrens Farm in Marion County, 1974-80.
Unpublished. |
PilotKnob81-82 |
Specimens collected by Rick
Lampe and others at Pilot Knob State Park, 1981-82.
Unpublished. |
Rabies |
Specimens from the State Hygienic
Lab in Coralville, IA. |
Rathbun78-82 |
Specimens collected by Iowa
Department of Natural Resources near Lake Rathbun, 1978-82.
Published in Bowles, J.B., and A.D. Copsey, 1992, Small
mammal abundance as a function of herbaceous cover type in
southcentral Iowa, Prairie Naturalist. |
RedRock |
Specimens collected on
shoreline at Lake Redrock by Paul Heideman, John Bowles, and
Kieth Erickson, 1978. Published in Heideman, P.D., J.B. Bowles,
and K.R. Erickson, 1983, Habitat selection by small mammals
on the shoreline of a flood control lake in south-central Iowa,
Proc. Iowa Acad. Sci. 90:93-97. |
SCS |
Soil Conservation Service
study by David Beck. Unpublished. |
ShrewStudy |
Specimens collected by John
Bowles and Jon Stravers in southeastern Iowa in 1984.
Unpublished. |
Temp |
(Temporary
category; samples still under review) Specimens collected by John Bowles, not yet
categorized and referenced. |
Unpub1 |
Individual specimens collected by a
private individual not for a specific study, mostly captured in Northeast Iowa.
Unpublished. |
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