116 
2. Abundance of soil fauna. Four sod cores, 
each 182.4 cm?, were removed from points 
chosen at random in each study plot at 10-day 
intervals in 1971 and 1972. Cores were shipped 
to Fairbanks, where macroarthropods were re- 
moved by drying and heating the core under a 
60-watt light bulb. Extracted specimens were 
preserved in alcohol until they could be 
counted. 
On 29 August 1972, a set of cores, each 22.9 
cm2, was taken from plots 11, 14, 15, 16, and 
17. These were brought to Fairbanks where 
replicate cores were subjected to O’Conner wet 
funnel extraction for Enchytraeidae and to 
Macfadyen high-gradient extraction for Acarina 
and Collembola. Each core was divided into 2.5 
cm depth increments to determine distribution 
of invertebrates with depth below the tundra 
surface. 
3. Phenology. Following a technique used 
at Barrow (MacLean and Pitelka 1971), two 
“sticky boards’ (each 1x0.1 m), were placed 
level with the ground surface on each study plot. 
The boards were replaced at 3-day intervals. 
Arthropods captured on the sticky surface were 
identified and counted under a dissecting micro- 
scope. Since most arctic insects have a very short 
adult lifespan, the distribution of ‘‘sticky 
board” catches through the season corresponds 
closely with the actual emergence of adult in- 
sects. The total number of captures in any plot 
provides an index of abundance that can be used 
in comparing year-to-year and between-habitat 
differences. 
Results 
1. Species composition and diversity. Al- 
though identification of the collection of Prud- 
hoe Bay insects is far from complete, it is 
obvious that species diversity is much higher at 
Prudhoe Bay than at Barrow. For example, 
collecting in one season produced 13 species of 
craneflies (two never before collected) at Prud- 
hoe Bay; collecting in many seasons at Barrow 
has produced only four species (Table 1). The 
greatest disparity between Barrow and Prudhoe 
occurs in the Dolichopodidae (long-legged flies) ; 
20 species were collected at Prudhoe Bay in 
1971, while the Barrow list has but one species. 
Prudhoe Bay has at least 12 butterfly species: 
Barrow has five. This difference is apparently 
due to higher within-habitat diversity and to the 
greater variety of habitats available in the Prud- 
hoe Bay region. 
David Atwood, USACRREL 
Adult insects captured on “sticky board” trap. 
Trap consists of 1x0.1 m board covered with a 
sticky resin and placed flush with tundra sur- 
face. 
Certain faunal groups that are scarce or 
lacking at Barrow are abundant and conspicuous 
at Prudhoe Bay. In walking across dry tundra, 
one is quickly struck by the abundance of large 
wolf spiders (Lycosidae), at least four forms of 
which are easily recognizable. At Barrow there is 
but one uncommon wolf spider (7arentula 
mutabilis), and the true bugs (Homoptera) are 
represented by a single, uncommon leafhopper 
(Cicadellidae) species (Hardya young/). At Prud- 
hoe Bay leafhoppers are very abundant on drier 
habitats, occurring in lower numbers elsewhere 
(Fig. 7). In addition, at least one species of leaf 
bug (Miridae) was found. 
2. Abundance of soil fauna. Larvae of vari- 
ous cranefly species (Diptera: Tipulidae) are an 
abundant component of many tundra eco- 
systems. At Barrow larvae of Pedicia hannai 
