477. 
478. 
479. 
Tevis, L., Jr. 1959. Man's effect on 
bighorn in the San Jacinto-Santa Rosa 
Mountains. Trans. Desert Bighorn 
Counc. 3:69-/6. 
Human encroachment threatens the larg- 
est continuous population of bighorn 
sheep in California. Changes in land 
use toward real estate development 
threaten to destroy sheep habitat and 
eradicate vital waterholes. Despite 
the risk of increased disturbance to 
sheep, promotion of the herd's recrea- 
tional value to tourists, photogra- 
phers, and sightseers is seen as the 
way to generate public support for 
sheep conservation efforts. 
TOURISM, WILDLIFE VIEWING, 
RANGELAND, URBAN ZONES, 
AGEMENT, BIGHORN SHEEP 
DESERTS, 
RECREATION MAN- 
Thelander, C. G. 1973. 
life investigations: 
production 
Special wild- 
Bald eagle re- 
in California, 1972-1973. 
Calif. Dept. Fish Game Project W-054- 
R-06/WP02/J05/8A. 18 pp. (MIN 04748- 
0284). 
Human disturbances interfere with nest 
selection and occupancy of bald eagle 
in California, posing a major threat 
to the already endangered population. 
A territory in a recreation area used 
by boaters, campers, and off-road ve~ 
hicles was abandoned by eagles in 
1972, possibly due to human distur- 
bance. 
BOATING, CAMPING, HIKING, OFF-ROAD VEHI- 
CLES, FORESTS, LAKES, THREATENED AND EN- 
DANGERED SPECIES, BALD EAGLE 
Thompson, R. W. 1980. Population dy- 
namics, habitat utilization, recrea- 
tional impacts and trapping of intro- 
duced Rocky Mountain goats in _ the 
Eagle's Nest Wilderness Area, Colora- 
do. Proc. Bienn. Symp. North. Wild 
Sheep Goat Counc. 2:459-464. 
Recreation impacts on mountain goats 
were assessed by simulating distur- 
bances and observing goat-human inter- 
actions in Colorado. Flight distance 
of goats was greatest for nanny-sub- 
adult groups, and averaged 82.6 m for 
all groups. The typical flight inten- 
sity was a slow walk away from the hu- 
man. It is concluded that recreation- 
al impacts on the goat population are 
slight. 
87 
480. 
481. 
482. 
DISTURBANCE (GENERAL), HIKING, 
TUNDRA, FLIGHT DISTANCE, U.S. 
FORESTS, MOUNTAIN GOAT 
FORESTS, 
NATIONAL 
Thornburg, D. D. 1973. Diving duck 
movements on Keokuk Pool, Mississippi 
River. J. Wildl. Manage. 37:382-389. 
Human disturbance from hunting, boat- 
ing, and other activities was found to 
be the primary cause of mass movements 
of ducks on the Keokuk Pool of the 
Mississippi River. The ducks adapted 
to human disturbance by deviating from 
typical patterns of diurnal activity. 
Intensive human activity at preferred 
feeding sites resulted in flights to 
less disturbed areas. Restrictions on 
boating activities in some areas of 
the pool may eventually be necessary. 
BOATING, HARASSMENT, RIVERS, WETLANDS, 
RECREATION MANAGEMENT, WATERFOWL 
Thorne, T., G. Butler, T. Varcalli, K. 
Becker, and 5S. Hayden-Wing. 1979. 
The status, mortality, and response to 
management of the bighorn sheep of 
Whiskey Mountain. Wyo. Game Fish 
Dept., Game Fish Res. Lab. Wildl. 
Tech. Rep. 7. 213 pp. 
Ecological aspects of bighorn sheep 
studied in Wyoming included responses 
of sheep to encounters with humans. 
Sheep responses to humans varied with 
sex, age, and activity of sheep, envi- 
ronmental factors, and the nature of 
the disturbance. All mountain recrea- 
tionists may stress sheep they encoun- 
ter; stress induced by such passive 
harassment might be the most serious 
consequence of man-sheep encounters. 
Management recommendations include 
control of human-sheep interactions. 
CAMPING, HIKING, WILDLIFE VIEWING, FISH- 
ING, CLIMBING, RESEARCH IMPACTS, TUNDRA, 
FORESTS, RANGELAND, FLIGHT DISTANCE, 
RECREATION MANAGEMENT, WILDLIFE MANAGE- 
MENT, U.S. NATIONAL FORESTS, BIGHORN 
SHEEP 
Tibbs, A. L. 1967. Summer behavior of 
white-tailed deer and the effects of 
weather. M.S. Thesis. Pennsylvania 
State University, State College. 93 
Pp. 
During research on summer behavior of 
white-tailed deer in Pennsylvania, req 
sponses of deer to the presence of the 
