Description of vegetation 
Following preliminary survey of the vegeta- 
tion, an intensive study was made by describing 
and estimating plant species composition in 
plots (33x100cm), as described by Gaare 
(1968). The 108 plots from the typical plains 
were analyzed with description of 5-15 plots 
per vegetation type. Plant groups were arranged 
into phyto-sociological vegetation types accord- 
ing to the European phyto-sociological system. 
Dominance, constancy, and Sorensen’s index of 
similarity were used to distinguish types (Dahl 
1956; Grieg-Smith 1964; Hanson and Churchill 
1961). Nomenclature follows Hulten (1968). 
Moss cover was not described in detail. * 
Tranquilizing caribou and field rumenotomy 
Caribou were tranquilized with 3 ml M99 
(Etorphine), which could be counteracted with 
3 ml of antidote M50-50 (Diprenorphine) 
[American Cyanamid Corp., Princeton, N. J.] at 
the end of the sampling protocol. Once the 
caribou was fully tranquilized, 3 ml of Aceprom- 
azine [Ayerst Lab, N. Y., N. Y.] was given 
intramuscularly, and field rumenotomy was per- 
formed using the first stage of a rumen fistula- 
tion technique as described by Dieterich (1975). 
This involved shaving the operating area, dis- 
infecting the site with Zepharin chloride [Winth- 
rop Lab., N. Y., N. Y.], and locating the rumen 
through a 5-7 cm incision. The rumen wall was 
sutured to the skin, and an incision was made 
through the rumen wall for collecting mixed 
rumen samples, using a plexiglass tube of 3.2 cm 
in diameter (O.D.) and 55cm in length. After 
sampling, the exposed edges of the rumen were 
folded into the rumen, and the rumen fistula 
was closed by suturing the rumen wall. Muscle 
tissue and skin was then sutured to close the 
incision. Care was taken to minimize spillage of 
contents, and the wound was dressed topically 
with Furacin Powder [Eaton Veterinary Lab., 
Norwich, N. Y.] to minimize infection. Long 
acting penicillin, 5m Longacil S [Fort Dodge 
Lab, Inc., Fort Dodge, lowa], was given intra- 
muscularly to provide long-term protection. 
Caribou from all five field rumenotomy opera- 
tions survived at least until the end of the study 
period (3 weeks). 
libs 
Description of reindeer 
Female reindeer of 2-5 yr of age were flown 
to Prudhoe Bay from the University of Alaska, 
Fairbanks. In 1972 two esophageal fistulated 
(EF) animals (Nos. 31 and 37), and two rumen 
fistulated (RF) animals (Nos. 10 and 12), were 
held in a small corral for the first week (July 
6-10), until they were accustomed to being 
tethered and had adapted to the available herb- 
age. No supplementary feed was given after July 
10. Body weight measurements were made in 
July. Following experience gained in 1972, only 
two animals (Nos. 9 and 31) were taken to 
Prudhoe Bay in the summer of 1973. Both were 
supplemented with 2.5-3.0 kg d'' Purina Cattle 
Starter No. 1 for the entire season, and body 
weights were recorded every 3 days (see below). 
During periods of severe insect attack, rein- 
deer were sprayed with insect repellant (“OFF,”’ 
S.C. Johnson and Son Inc., Racine, Wisc., or 
Insect repellant Type IIB, Federal Specification 
0-1-503) and were tethered in the most windy 
areas or were allowed freedom of movement in 
the holding corral. 
Body weight determinations 
Estimates of body weights of caribou and 
reindeer were made using a system involving 
four bathroom scales. An army stretcher or a 
wooden platform (2.5x1m) was placed on the 
scales, which were then turned to zero. Tranquil- 
ized caribou were lifted onto the stretcher, and 
live reindeer were trained to stand on the plat- 
form while the four scales were read concur- 
rently. Reproducibility of the technique was 
+ 1.0 kg. 
Esophageal fistula collections 
Samples from esophageal fistulated animals 
were collected over 10 or 20 min time periods. 
The esophageal plug was removed during a col- 
lection, and upon swallowing, egesta was extrud- 
ed through the fistula and collected in a plastic 
bag fitted with a liner of nylon mesh (10-12 
threads cm''). The nylon mesh served to 
retain the forage and allowed saliva to strain into 
the plastic bag. This apparatus was fitted into a 
canvas bag (30x18cm) which supported the 
plastic bag and liner and which could be attach- 
ed to the neck of the reindeer. 
“This scheme of classification is compared with a more detailed study by Webber and Walker (this volume). 
