eer mice, were also less abundant then, and the numerous horned
owls may have been supported in part by the high population of woodrats.

The spotted skunk may be an even more important enemy of the woodrat,
although the evidence is circumstantial. No records of these skunks
preying on woodrats have been found in the literature, nor were any such
instances recorded by us except for attacks on woodrats confined in
live-traps. This skunk is a formidable enemy of small and medium-sized
rodents, as it can climb, dig, and squeeze through small openings. That
it may prey on rat-sized rodents and may even be a limiting factor to
their occurrence is well shown by Crabb's (1941:353) studies in Iowa. He
found that Norway rats (_Rattus norvegicus_) ranked third in frequency
(cottontail, mostly carrion, ranked first) in the winter food of the
spotted skunk. Crabb observed that about farmyards and farm buildings
where the skunks had been eliminated by persistent persecution, rats
were abundant, but that about others where the skunks were present, the
rats were scarce or absent. On several occasions he noted that heavy
populations of rats about farm buildings in summer and autumn nearly
disappeared in winter if a skunk was in residence.

Sign of spotted skunk was noted frequently on various parts of the
Reservation, especially along the hilltop ledges which were the best
woodrat habitat. On several occasions skunks released from live-traps
took shelter in woodrat houses which appeared to be unoccupied.
According to a local fur dealer, C. W. Ogle, spotted skunks reached a
peak of abundance in Douglas County in the winter of 1947-1948, and many
pelts were brought in for sale then. The concentration of skunks may
have had detrimental effect on the population of woodrats, especially
when extremes of weather had already made conditions critical for them,
as in early March, 1948, and in January, 1949, when snow and sleet made
their usual food supply unavailable.

The long-tailed weasel is considered to be a potentially important enemy
of the woodrat. Weasels have been seen on the Reservation on only a few
occasions, but they may be more numerous than these records would
indicate. Two were caught at the hilltop outcrop, at different times and
places, in funnel traps put out to catch snakes. The weasel seems to
prefer this rocky habitat, which is also favored by the woodrat. Because
of its ferocity and willingness to attack relatively large