June July Aug 
a. Numbers of birds counted (all species) by date and row of 
census plot. 
= b. 
= 2 Lake Shore: 
> Before 20 June 
© | After 20 June 
Lu 
@ O ns 
o A B ce D E 
Row 
b. Schematic cross section of Plot B, showing approximate ele- 
vation above lowest point on the east margin of the plot. 
Fig. 3. Spatial and temporal patterns of avian 
abundance, Plot B, Prudhoe Bay, 1977. 
productivity and species diversity of sites at 
different latitudes and dominated by various 
physical factors. At one end of this continuum 
are the preliminary results of Pattie (1972) from 
Devon Island in the Canadian arctic. The other 
end of the continuum would presumably lie in 
tropical rain forests. Table 4 summarizes popula- 
tion estimates and such energy flux estimates as 
exist from nine northern community types for 
approximately ecologically equivalent compo- 
nents of the avifauna (insectivores and grani- 
vores), as discussed in this study. Farther south, 
species diversity, the relative importance of pas- 
serines, total avian biomass, and energy flux 
through avian populations may be expected to 
increase. Holmes and Sturges (1973), for 
example, estimated that a minimum of 5x10® 
kcal km? yr! was ingested by temperate forest 
birds at Hubbard Brook, N. H. The pieces of this 
global picture will probably continue to come 
into sharper focus with the present emphasis on 
measuring productivity at many sites. 
131 
=> 
See 
15 June l971 
= Lal 
{ 1 
oreline 
nie sonic 
Recaptured, re-nesting 
off plot in 1972 
@ 197! Nest <> 
@i972Nest 
@ —>@ Re-nest 
@—-B Return 
~ Deep Water 
42 Shallow w/Emergent 
Vegetation 
Fig. 4. Schematic recapture histories of Semi- 
palmated sandpipers from 1977 nests on Plot B, 
showing site-tenacity and mate-faithfu/ness. 
All breeding birds at Devon Island, Barrow, 
and Prudhoe Bay are subjected periodically to 
widespread reproductive failure because of 
predation and probably physical factors. In the 
case of nest predation at Prudhoe Bay in 1971, 
it is likely that human activities were at the base 
of a chain of events leading from garbage dis- 
posal through attraction of foxes and abnormal- 
ly heavy predation pressure by them to avian 
reproductive failure. Garbage disposal is a criti- 
cal problem for industrial development in Alas- 
ka, as elsewhere. Improper disposal, leading to 
unnatural attraction of potentially nuisance or 
noxious species, is a quick, sure, and subtle 
modifier of ecosystem function, especially 
where the volume of garbage is great. 
Another form of human impact on systems 
function has arisen from ground transportation 
developments in the Prudhoe Bay region. Raised 
roadbeds alter the accumulation of wind-driven 
snow and may significantly impound water dur- 
ing spring runoff. Downwind fallout of dust and 
