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.

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:

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 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