materials, the 
  
| from metrical 
features seen 
e located and 
nd shoal may 
ot completely 
anding beach 
tly, measure- 
, a dark line 
cet wide, and 
s intelligence 
Il and usable 
IIs, embank- 
it the prepa- 
ole accuracy. 
and directly 
The scale of 
ilable maps, 
[titude ratio. 
lief is made 
ns) are nor- 
ind. parallax 
iust be made 
  
  
Reprinted from 
PHOTOGRAMMETRIC ENGINEERING 
March 
1953 
AERIAL PHOTO USE AND INTERPRETATION IN THE 
FIELDS OF WILDLIFE AND RECREATION* 
Daniel L. Leedy, Biologist, U. S. Fish and Wildlife Service 
VV ORRERS in the fields of wildlife management and recreation have made 
fairly extensive use of aerial photographs as maps and for inventorying 
certain wildlife species. Although they have devoted but little time or effort to 
developing special photographic interpretation techniques by means of which 
aerial photographs could be used in wildlife research and development projects 
most effectively, they have made a beginning; and one notes more and more 
references in current literature to such uses and techniques. 
Broadly speaking, wildlife is a product of soil and water, field and forest; 
therefore, many of the photographic interpretation techniques described at the 
VII International Congress of Photogrammetry, as applicable in making in- 
ventories of forests, water, soils, minerals, farms and range lands, are also useful 
in wildlife and recreation inventories. 
Indicative of the interest shown in wildlife and recreation are the facts that 
in the United States alone last year, visitors to the National Parks and Monu- 
ments numbered nearly 37,000,000; there were approximately 28,000,000 
licensed hunters and fishermen; and more than 50 colleges and universities 
offered training in wildlife conservation. In preparation for work in the field of 
wildlife management, students take a large variety of courses, including botany, 
zoology, agronomy, soils, range management, forestry, statistics, and limnology. 
A few students may take a course in photogrammetry or get a general introduc- 
tion to photographic interpretation in a wildlife techniques course. However, 
few, if any, of the many Federal, State, Provincial or private agencies charged 
with managing this country's wildlife resources employ photographic inter- 
preters. Correspondence with wildlife biologists in Denmark and England re- 
vealed that relatively little use is made of aerial photography in connection with 
wildlife work in those countries. 
Among the state conservation commissions pioneering in the use of aero- 
planes in wildlife work were Wyoming, which made aerial surveys of elk in- the 
Jackson Hole area in 1935, and Missouri, which surveyed proposed refuge sites 
in the timbered Ozark area before aerial photographs were available from the 
usual Government sources. Since World War II, most of the state conservation 
departments have made use of aeroplanes. A study by Clyde P. Matteson, 
Aeronautical Technician of the Colorado Game and Fish Department (1950) 
showed that of 46 states replying to his questionnaire, 42 used aeroplanes in 
their wildlife programs. Of these 42 states only 12 considered aerial photography 
of sufficient importance to list it as a part of their aerial work. Approximately 
half of the states owned planes, and the other half rented them or hired both 
planes and pilots. The planes were used primarily for big game and waterfowl 
census work. 
Relatively few uses of aerial photographs, except as maps, have been re- 
ported in wildlife literature. Aerial photographs were used in describing study 
areas by Yeager (1941) and Hochbaum (1944), to cite but two instances; and as 
a basis for cover mapping by Dalke (1937), Crawford (1946), Marshall (1946), 
Wilson and Berard (1952), and others. In an earlier article by the author 
(Leedy, 1948) aimed at acquainting wildlife technicians with aerial photographs 
* Prepared for Seventh International Congress. Permission for publication granted by Inter- 
national Society of Photogrammetry. 
1