Proceedings of the fifth mountain lion workshop: 27

74 PROCEEDINGS OF THE FIFTH MOUNTAIN LION WORKSHOP
PHOTOGRAPHIC RECORDING OF MOUNTAIN LION TRACKS
K. Shawn Smallwood. Consulting in the Public Interest, 109 Luz Pl., Davis, CA 95616
Melissa Grigione. Department of Environmental Studies, University of California, Davis, CA 95616
Key words: California, Mountain Lion, Photography, Puma concolor, Tracks
Track count methodology for mountain lion (Puma
concolor) has been under development in California since the
1970's (Koford 1978, Kutilek et al. 1983, Fitzhugh and
Gorenzel 1985, Smallwood and Fitzhugh 1995). One of the
methodological problems has been the recording of tracks
along the transect for the purposes of identifying and
cataloging individuals based on track measurements
(Smallwood and Fitzhugh 1993). The problems include
recording error and time required to record the tracks. The
method of tracing tracks onto acetate sheets (Panwar 1979)
forces the investigator onto his/her hands and knees for up to
an hour per track set. This method is prone to mixing of dust,
sweat, fatigue, and parallax through the glass plate. At least
four tracks per rear foot (tracks of rear feet are most often the
only available) need to be recorded for reasonable variance
estimates. During the last two years we developed
photographic methods for recording tracks on snow and dust
substrates.
Grigione focused on recording tracks on snow, which
were made by known radio-collared mountain lions near the
Owen's Valley, California. Smallwood focused on recording
tracks from dust along dirt roads throughout California during
his statewide mountain lion track counts (Smallwood 1994,
Smallwood and Fitzhugh 1995). He switched to photography
at the beginning of the 1995 track count, and also
photographed tracks made by black bear (Ursus americanus),
bobcat (Felis rufus), coyote (Canis latrans), raccoon (Procyon
lotor), striped skunk (Mephitis mephitis), and badger (Taxidea
taxus). Thus, we draw on a broad background of trackrecording
experience and field conditions to describe the
benefits and problems encountered when using photography
to collect track data.
PHOTOGRAPHY
In the snow Grigione used a 35 mm Nikon SLR
camera with manual focus and automatic aperture. She used
asa 100 color slide film, and shot the photos from a tripod.
Filters, flashes, and umbrellas were used in various
combinations to enhance or diminish the natural light. The
tracks varied in depth of depression below the surrounding
snow surface, and therefore the lighting conditions varied
considerably. Each photo included a ruler and a square inch
wood block for scale.
During the first several weeks of the 1995 statewide
track count, Smallwood used a Minolta SRT201 body with a
70-210 mm variable lens and a lens hood. During the last
several weeks he used a Minolta X-700 body with a
Minolta1:3.5, 50 mm macro lens, which had a built-in lens
hood. Throughout the track count he used 35 mm asa 100
color slide film from Seattle Filmworks. Smallwood usually
carried a photographic umbrella to provide uniform light
conditions, despite tree overhangs. However, he usually overexposed
the photos by turning the f-stop 2 "clicks" beyond the
recommended exposure provided by the light meter when
using a manual camera, as per the advise of a professional
photographer. The light meter of manual cameras needs to be
respected when using a photographic umbrella.
The first two rolls of film made during the track
count included some photos that were blurred by hand
movement of the 70-210 mm variable lens while shooting.
Once this problem was realized, more care was taken not to
move the camera. The best photos were made with the X-700
body and the macro lens. This camera-lens combination was
easy to use and produced more clear, flat photos. Focus and
exposure were automatic. Smallwood took about 1000 photos
of tracks throughout the track count, including those of other
mammalian carnivores, and only two or three photos will pose
problems in interpretation. Most of the rest were excellent,
and will be easy to trace for GIS application (described
below). Simple camera arrangements prevent mistakes and
malfunctions.
We searched track sets in both directions along roads
for the clearest tracks and the safest road conditions, where
vehicle traffic might pose a hazard. We placed a metric ruler
for scale next to each track to be photographed, as well as a
small piece of thin cardboard showing species, date, transect
name, and distance from the start of the transect. The same
piece of cardboard was used for all the photographed tracks
along a track set. The cardboard was always placed just
outside the boundary of the track.
Most photos were of a single track each, although
pairs of tracks were included within the same photo when they
were close together. Pairs of tracks often were photographed
together for black bear, and sometimes for mountain lion,
bobcat, raccoon, and coyote. More tracks were sometimes
included within each frame for striped skunk and other smallbodied
carnivores with short stride lengths. However, the goal
for each shot was to get as much track detail as possible
throughout the picture frame. The photos were best taken
from a kneeling position.