confidence levels of 0.0496 percent to 0.1780 percent. This indicates
that a 10:1 ratio of methiocarb to adhesives would be effective in
repelling blackbirds.

Evaluation of rodent glues

Toxic baits are the most common means of controlling rodents in crop
damage situations. However, there are instances in which an alterna-
tive, nontoxic method may be more desirable or necessary. For exam-
ple, in situations where abundant food is available, rodents may not
be attracted by baits. In other situations they may have ingested
sublethal doses, become bait-shy, and simply will not accept toxic
baits.

We are exploring several alternative, nontoxic methods of rodent con-
trol in field crops. One of these possible alternatives is rodent
glues, substances that are currently used in commensal rodent control.
The concept is simple; the glue, on a glue board or similar carrier,
is placed where rodents will walk on it. They become stuck, unable
to extricate themselves. They may then be removed and destroyed.
Several of these substances are available commercially and may have
application in certain field situations.

We tested three of these products in the laboratory. A test chamber,
approximately 240 cm X 25 cm X 25 cm was designed to hold about 4 cm
of water (to simulate a rice paddy) and a glue board. Five Philippine
rice rats were tested with each glue. In every instance, the test
animals were held fast (even though they were wet) and remained so
during the 2-h test period. While these results are favorable, they
are prelusive and further testing, both in the laboratory and under
field conditions, is necessary.

Automatic data-acquisition system for measuring the bait intake of
ricefield rats (R. r. mindanensis)

In the 1977 Annual Report, we discussed the initial results of a study
to analyze the minute-by-minute feeding patterns of ricefield rats.
Bait consumption was monitored using a single electronic balance
programed to automatically record food consumption on cassette tapes.
Essentially, results showed that: (1) rats feed on bait for only
limited portions (i.e., 35-90 min) of each 24-h period, and (2)
feeding patterns of rats presented with zinc phosphide or warfarin
baits are characterized by intermittent, 1- to 3-min samplings of
<0.1 g of bait, whereas, rats given nontoxic bait eat several 5- to
10-min "meals" (i.e., 0.5-1.5 g of bait) separated by 1- to 2-h non-
feeding intervals.