APPENDIX G 
Perfection of the airplane as a mapping device brought hope 
that a new fur-seal census method might be developed. In 1938 Superin- 
tendent Harry J. Christoffers left Village Cove, St. Paul Island, in a 
U. S. Coast Guard seaplane and cruised for a time over the rookeries 
(U. S. Bureau of Fisheries, 1938, p. 162). He took a few motion pictures 
and still photographs but found them of no practical value. 
On 9 July 1945 one of us (Scheffer) flew witha U. S. Navy 
photographic mission in an amphibious plane (PBY) over certain rookeries 
of St. Paul Island. Eighty-three 4- by 5-inch negatives were obtained 
with a K-20 aerial camera, most of them oblique views. The experiment 
was useful to the extent that it pointed out the need for larger nega- 
tives and complete vertical coverage of the rookeries. | 
In the summers of 1947, 1948, and 1949, Scheffer and Kenyon 
took experimental photographs with a 4- by 5-inch camera suspended from 
a captive balloon (Scheffer, 1950b, illus. on p. 22). They were unable 
to control twisting and swaying of the camera and eventually decided to 
postpone experimentation with this device. 
From 13 to 15 July 1948, Scheffer and Kenyon flew over all of 
the rookeries on the Pribilof Islands in a twin-engine land plane 
equipped with an F--56 camera with an 8.5-inch lens. The runs were made 
at elevations of 900 to 1,200 feet and at a ground speed of about 90 mph. 
Two aerial missions were flown by the U. S. Air Force, mither 
of which produced useful negatives for this study. On 27 July 1948 the 
Tenth Rescue Squadron flew a PBY mission from Anchorage, Alaska. On 19, 
28, and 29 July 1949, the Second Air Force flew a B-29 mission from 
Barksdale Air Force Base, Louisiana. 
The first attempt to photograph the fur-seal rookeries from a 
helicopter was made on 19 July 1951 when the Navy icebreaker U.S.S. 
Burton Island with two helicopters aboard stopped at St. Paul Island. 
Through the courtesy of Commander J. R. Schwartz, in charge, Lieutenant 
R. L. Maghan was assigned to take one of us (Kenyon) aloft. Photographs 
of the seal rookeries were taken with a 3-1/4~ by 4-1/4-inch camera from 
altitudes of 100, 200, and 400 feet. The seals were badly frightened by 
the violent downdraft and noise from the rotor blades, and stampeded even 
when the helicopter was at 400 feet. Although the photographs were clear, 
they did not furnish appreciably better results than were obtained in 
1948. It is concluded that at the present time the helicopter is impractical 
for large-scale photography of fur-seal rookeries at altitudes permitting 
a count of individual seals. 
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