Probably no instinct is of greater importance to the kangaroo rat than
that of storing food supplies. When a crop of desirable seeds is
maturing the animal's activities appear to be concentrated on this work.
During September, 1919, when a good crop of grass seed was ripening
following the summer rains, a kangaroo rat under observation made
repeated round trips to the harvest field of grass heads. Each outward
trip occupied from 1 to 1-1/2 minutes, while the unloading trip into the
burrow took only 15 to 20 seconds.
One individual in a laboratory cage, which had not yet been given a nest
box, busied itself in broad daylight in carrying its grain supply into
the darkest corner of the cage. When a nest box is supplied the
individual will retreat into its dark shelter, and will only come forth
after darkness has fallen unless forcibly ejected, but will store the
food supplied.
In another case an animal escaped while being handled, and sought refuge
behind a built-in laboratory table, where it could not be recovered
without tearing out the table. For four days and nights it had the run
of the laboratory. On the first night of its freedom it found and
entered a burlap bag of grass seed that had been taken from a mound. A
trail of seed and chaff next morning showed that it had been busily
engaged in making its new quarters comfortable with bedding and food.
After four nights of freedom it was captured alive in a trap, and later
it was found that it had moved from the corner behind the table to the
space beneath a near-by drawer, where it had stored about 2 quarts of
the grass seed and a handful of the oatmeal used for trap bait.