204. 
205, 

ports on the bald eagle research proj- 
ect. Can. Audubon 28: 88-92. 
This nontechnical article describes 
observations and research results ob- 
tained from a study of bald eagles in 
British Columbia. Human visitation to 
nests caused little mortality the year 
of the visits, but in the following 
year nests visited previously showed a 
65% reduction in number of young pro- 
duced. More research is needed on the 
effects of nest disturbance to under- 
stand the impacts of recreational ac- 
tivities and biological research on 
nesting eagles. 
DISTURBANCE (GENERAL), RESEARCH IMPACTS, 
WILDLIFE VIEWING, COASTAL ZONES, FOR- 
ESTS, THREATENED AND ENDANGERED SPECIES, 
U.S. NATIONAL FORESTS, BALD EAGLE 
Hand, J. L. 1980. Human disturbance in 
western gull Larus occidentalis livens 
colonies and possible amplification by 
intraspecific predation. Biol. Con- 
serv. 18:59-63. 


Human disturbances are affecting re- 
production of western gulls at several 
colonies in the Gulf of California. 
Breeding adults that lose chicks or 
eggs apparently practice conspecific 
predation, amplifying the effects of 
human disturbance. These combined ef- 
fects may pose a threat to the surviv- 
al of this endemic population. 
DISTURBANCE (GENERAL), TOURISM, COASTAL 
ZONES, PREDATION, WESTERN GULL 
Hanson, OD. 
peregrines. 
1980. Of parachutes and 
Audubon 82(6):62-65. 
This popular article describes recent 
National Park Service actions regard- 
ing the management of skydivers in Yo- 
semite National Park. Skydiving off 
of 3,600-foot high E] Capitan, an 
overhanging cliff, threatened the Si- 
erra Nevada's only known pair of nest- 
ing peregrine falcons. An attempt to 
manage skydiving through a legalized 
permit system was rescinded after sev- 
eral serious injuries occurred and il- 
legal jumping continued. 
CLIMBING, SKYDIVING, FORESTS, THREATENED 
AND ENDANGERED SPECIES, RECREATION MAN- 
AGEMENT, U.S. NATIONAL PARKS, PEREGRINE 
FALCON 
39 
206. 
207. 
208. 
Hanson, OD. 4G. 1975. Non- feathered 
friends for the seabird sanctuary. 
Conserv. News 40(1): 2-6. 
Activities at a seabird sanctuary and 
rehabilitation center in Florida are 
described in this popular article. 
Birds injured by fishing gear are com- 
monly treated at the center; pelicans 
seem especially prone to such injur- 
jes. Bird collisions with powerlines, 
plate glass, and vehicles are also 
common sources of injury, and some 
birds treated at the center have been 
victims of deliberate cruel actions by 
humans. 
FISHING, HARASSMENT, COASTAL ZONES, 
THREATENED AND ENDANGERED SPECIES, WILD- 
LIFE MANAGEMENT, BROWN PELICAN, SEA- 
BIRDS, WATERBIRDS 
Harms, D. R. 1980. Black bear manage- 
ment in Yosemite National Park. Pages 
205-212 in C. J. Martinka and K. L. 
McArthur, eds. Bears--their biology 
Fourth International] 
Conference on Bear Research and Man- 
agement, February 1977, Kalispell, 
Mont. Bear Biology Association. 
and management. 
A management program was implemented 
in 1975 to reduce conflicts between 
park visitors and black bears in Yose- 
mite National Park. Bear damage pat~ 
terns monitored before and during the 
Management program indicate that the 
program is achieving its objectives. 
CAMPING, HIKING, SKIING, SWIMMING, FOR- 
ESTS, HUMAN HEALTH AND SAFETY, RECREA- 
TION MANAGEMENT, WILDLIFE MANAGEMENT, 
U.S. NATIONAL PARKS, BLACK BEAR 
Harris, M. P. 1973. Seabirds and tour- 
ism. Pages 300-302 in P. Jackson, ed. 
World wildlife yearbook 1972-73. 
World Wildlife Fund, Morges, Switzer- 
land. 
Impacts of tourism on seabirds are 
discussed in this nontechnical report. 
As people in the more affluent coun- 
tries have gained more leisure time 
and air travel has become less expen- 
sive, many previously remote seabird 
colonies have suffered disturbance by 
tourists. As the economic value of 
wildlife-based tourism is recognized, 
however, many countries are beginning 
to actively protect and conserve sea-~ 
birds as an economic resource, 
