Actual or potential impacts of exploitation 
and transportation of arctic oil and gas on 
biological systems have gained a great deal of 
attention, but sufficient time and funding for 
serious, long-term scientific evaluation of these 
impacts have not been available. Consequences 
of such activity which may directly and nega- 
tively affect resident birds include noise disturb- 
ance; loss, destruction, or alteration of habitat, 
and spills of toxic materials. But these are 
obvious effects which could be offset with 
obvious countermeasures. One can argue that 
the extirpation of a few breeding species from a 
limited area may be unimportant. Historically, 
the less obvious effects of human activities have 
had far greater consequences for ecological 
systems. We therefore tried to identify any such 
systems effects as we encountered them in the 
course of this 2-year study. We viewed the small 
species with which we were dealing more as 
ecological indicators than as valuable resources 
in themselves. This approach is basically differ- 
ent from a resource management approach such 
as that of a waterfowl biologist, whose mandate 
is to protect and enhance productivity. 
Methods 
Visual census coverage of measured tracts, as 
developed for avifaunal studies at Point Barrow 
(Norton 1973), was used to evaluate the dynam- 
ics of bird populations using Prudhoe Bay tun- 
dra. Two census plots, A and B, each measuring 
500x700 m (0.35 km), were erected and mark- 
ed in 1971. A third plot, C, measuring 
200x500 m (0.1 km2), was erected in 1972 and 
deliberately located away from the lee, or west, 
side of nearby roads (Fig. 1). 
Each plot was censused systematically by 
one to three observers who walked the grid and 
recorded locations of each bird encountered. 
The intervals between formal censusing (4-12 
days depending on weather, level of activity, and 
estimated rates of change in populations 
present) were used in searching for nests, color- 
banding adult and young birds trapped at their 
nests, and recording the progress of nests under 
observation. The proportion of birds, either 
unbanded or unaccounted for as nesting, theore- 
tically should drop to near zero if the technique 
is successful. 
General observations outside the census 
127 
Calidris pusilla 
Tryngites subruticollis 
2 ? ? ? 
°E , | | 
Calidris alpina 
Clutches Completed per Day 
2 
O 
2 Calidris melanotos 
fe) 
2 Lobipes /obatus 
O 
Calcarius lapponicus 
A Ualilalilssilapal A Ueda wett cue eee a 
O 
5 10 15 20 25 30 5 
0 Successful hisri @ Successful July 
M Predated ! @ Predated 
Fig. 2. Breeding phenology measured by clutch 
completion dates for seven species at Prudhoe 
Bay, 1971, 1972. 
plots also were made regularly over the wide 
area accessible by the road system. This study 
thus complements that of Gavin (1971), which 
deals primarily with waterfowl. Gavin lists 54 
species observed in 1969 and 1970 over a much 
wider geographical area. However, his treatment 
of small terrestrial species was incomplete. 
Results 
Table 1 lists the 53 species of birds encoun- 
tered during the two-season survey and distin- 
guishes known breeding, suspected breeding, 
regularly and casually occurring species. Al- 
though we could certainly have expanded this 
list through attentive observation, particularly 
during the spring influx of species, we were 
preoccupied with the regularly occurring species 
that accounted for the major share of tundra 
resource use in this region. 
Of 34 known or suspected breeding species 
in Table 1, only seven regularly used primarily 
terrestrial resources to support breeding within 
