WILDLIFE SOFTWARE

               SIMPLIFIED PLOTTING ANALYSIS AND DATA STORAGE
                           (SPADS) FOR TELEMETRY

NEERJA JUNEJA, Department of Mathematics, Computer Science and Engineering,
     University of Maryland Eastern Shore, Princess Anne, MD 21853

GERBAX SINGH, Department of Natural Sciences, University of Maryland Eastern
     Shore, Princess Anne, MD 21853

TERRY L. BASHORE, Coastal Ecology Research Laboratory, University of Maryland
     Eastern Shore, Princess Anne, MD 21853

     Radiotelemetry is often used to estimate an animal's location and is the
primary means used to collect data for home range analysis. Microcomputers can be a
useful tool for collection and analysis of these telemetry data. Some of the available
microcomputer programs were designed to estimate the animal location from telemetry
data; whereas, others calculate the home range using different methods and location
data. TRITEL (D. E. Biggins, unpubl. rep., U.S. Fish and Wildl. Serv., 1984), TRIANG
(White and Garrott 1984), and XYLOG (Dodge and Steiner 1986) are useful to determine
the animal location from telemetry data. McPAAL (Stuwe and Blohowiak 1985) is designed
for estimating the home range from location data.
     SPADS was developed for estimating both the location and the home range of
radio-tagged wildlife. Telemetry data, in terms of longitude and latitude, from up
to 5 receiver stations can be entered. The receiver stations and the bearing
directions are displayed on the screen for visual verification of the data. Animal
locations are estimated from the coordinates of all valid bearing intersections (Mech
1983, Dodge and Steiner 1986).
     Animal locations collected over a period of time are stored in separate files
for each animal. Data for up to 30 animals can be stored. Each data file can have up
to 1,000 data points. However, these limits can be easily changed.
 The home range area can be estimated by using any 1 of the following 3 methods:
bivariate normal model (Jennrich and Turner 1969, Koeppl et al. 1975, Macdonald et
al. 1980), circular normal model (Macdonald et al. 1980), and the convex polygon
method (Mohr 1947, Southwood 1966, Kenward 1987). Locations and the estimated home
range can be viewed on a high resolution VGA monitor.
     The program is designed for the northwestern hemisphere. The estimation of the
home range is limited to 224 x 224 square kilometers (2 x 2 degrees), which is large
enough for most applications. This limit is imposed by the inability of PASCAL to
handle large integers.
     SPADS is written in TURBO PASCAL 5.0 and runs on an IBM PS/2 model 30-286 or
compatible. It requires about 100 Kilobytes of disk space. About 50 bytes are required
to store information about an animal and 30 bytes for each data point which includes
the date and time of observation, and the estimated longitude and latitude coordinates
of the animal. The program source code, executable code, user documentation, and test
data are available on the southeastern software change (SESAME) on-line bulletin board

LITERATURE CITED

DODGE, W. E., AND A. J. STEINER. XYLOG: a computer program for field processing of
     radio-tagged wildlife. U.S. Fish and Wildl. Serv. Tech. Rep. 4. 22pp.

JENNRICH, R. J., AND F. B. TURNER. Measurement of non-circular home range. J.
     Theoret. Biol. 22:227-237.

KENWARD, R. E. 1987. Wildlife Wildlife radio-tagging: equipment, field techniques
     and data analysis. Academic Press, New York, N.Y. 222pp.

KOEPPL, J. W., N. A. SLADE, AND R. S. HOFFMAN. 1975. A bivariate home-range model
     with possible application to ethological data analysis. J. Mammal. 56:81-90.

MACDONALD, D. W., F. G. BALL, AND N. G. HOUGH. 1980. The evaluation of home range
     size and configuration using radio tracking data. Pages 405-424 in C. J.
     Amlaner and D. W. Macdonald, eds. A handbook on biotelemetry and radio
     tracking. Pergamon Press, Oxford England.

MECH, L. D. 1983. Handbook of animal radio-tracking. Univ. of Minnesota Press,
     Minneapolis. 107pp.

MOHR, C. O. 1947. Table of equivalent populations of North American small mammals.
     Am. Midl. Nat. 37:223-249.

SOUTHWOOD, T. R. E. 1966. Ecological methods. Methuen, London, England. 391pp.

STUWE, M., AND C. E. BLOHOWIAK. 1985. McPAAL. Conserv. and Res. Cent., Natl. Zool.
     Park, Smithsonian Inst., Front Royal, VA. 18pp.

WHITE, G. C., AND R. A. GARROTT. 1984. TRIANG: portable computer system for field
     processing biotelemetry triangulation data. Colo. Div. Wildl. Game Inf.
     Leafl. 110. 4pp.

Received 3 January 1991.
Accepted 24 January 1991.