Determining Forage Consumption by Direct Observation of Domestic Grazing Animals 
ARDELL J. BJUGSTAD', HEWLETTE S. CRAWFORD’, and DONALD L. NEAL? 
The purpose of this paper is to review meth- 
ods of directly observing grazing animals— 
mainly cattle—to determine their forage con- 
sumption and possibly the reasons why they 
desire certain plants at certain times of the 
grazing season. The methods described are 
evaluated for research purposes. 
Three basic methods are considered: (1) 
The cafeteria or free-choice method, (2) the 
feeding-minutes method and (38) the evalua- 
tion-of-grazing-patterns method. 
GENERAL TECHNIQUES 
One of the advantages of direct observation 
is that only a small investment in equipment is 
needed. Observations are conducted similarly 
in most cases; e.g., one or more men on foot 
watch selected animals. Binoculars are com- 
monly used; however, observations have been 
done by the unaided eye. Sometimes a spotting 
scope is used to achieve greater accuracy. 
Flashlights and headlights have been used to 
aid night observation. 
Brands, dyes, ear tags, and neck chains as 
well as natural coloring and conformation have 
been used to identify individual animals. An- 
imals can be belled—a bell of different tone for 
each animal—to aid in locating them at night 
(Wagon 1963) and in the brush, or a radio 
tracking system can be used. However, the 
most common method to ease identification of 
individual animals is painting large numbers 
or letters on the sides of the test animals. Cur- 
rie (1966) found that women’s hair dye was 
an excellent marking liquid. Nelson and Furr 
(1966) added reflective glass beads to their 
marking liquid to aid in location and identifi- 
cation at night. 
Some animals, especially sheep, are difficult 
to approach and must become accustomed to 
the observer. A blind, as suggested by Hughes 
and Reid (1951), can be used to hide the ob- 
server from the animals. Neal and Newman 
(unpublished 1968) used 15-foot portable 
hunting towers to increase visibility in shrub 
cover. Cattle become accustomed to the towers 
*Respectively, Range Scientist and Principal Ecolo- 
gist, U.S. Department of Agriculture, Forest Service, 
North Central Forest Experiment Station, Columbia, 
Mo. The field office at Columbia is maintained in coop- 
eration with the University of Missouri Agricultural 
Experiment Station. Headquarters for the field office is 
St. Paul, Minn. 
* Range Scientist, U.S. Department of Agriculture, 
Forest Service, Pacific Southwest Forest and Range 
Experiment Station, Berkeley, Calif. 
and graze very close to them. Cattle also allow 
close observation by men in a pickup truck 
(Reppter 1960) or by men on horseback, as 
they are accustomed to seeing men this way. 
When two or more men are observing, low- 
power citizen’s band ‘‘walkie-talkie”’ radios are 
used to prevent duplication of effort—two men 
watching the same animal during the same pe- 
riod—or to assure duplication when it is de- 
sired. Radios used by two or more people also 
aid in locating specific animals without undue 
searching. 
Sheep present a special problem because of 
their gregarious nature. The observer often 
loses sight of his subject in the band. It is dif- 
ficult to observe grazing in the shrub communi- 
ties because the larger plants restrict the view. 
Tame animals that can be followed closely are 
a great help. 
Observation periods must be planned to coin- 
cide with the feeding periods of the animals, 
and the time pattern of feeding needs to be 
learned before the formal study is begun. Both 
sheep and cattle tend to do most of their feed- 
ing in the morning and evening. Cattle feed 
about 9 hours per day and sheep about 6. 
Weather records are important when inter- 
preting observation data and should be accur- 
ately kept during each observation period. For 
example, snowfall can force cattle to switch 
from grazing to browsing, and hot, humid con- 
ditions can cause them to graze in shaded 
areas. 
As the observer works with a given vegeta- 
tion type and class of animal, he gains skill 
rapidly. He learns to use animal position and 
movement, plant movement and even sounds to 
help determine what plant the animal is con- 
suming. However, studies in California and Or- 
egon have shown that even with experience 
and careful planning, it takes about 300 man- 
hours to observe animals for 100 hours. 
Each method has certain advantages and 
disadvantages for research use. The methods 
are described here and are rated as range re- 
search techniques. 
CAFETERIA OR FREE CHOICE METHOD 
This method permits the animals to select 
their forage from a number of equally accessi- 
ble species made available in approximately 
equal amounts (Joint Committee of the Ameri- 
can Society of Range Management and the Ag- 
ricultural Board 1962). The forage may be fed 
in bunks, in dry lot, or in pure-stand pasture 
plots. The animals feeding at bunks or plots 
101 
