considered cautiously because its e

considered cautiously because its effectiveness is unknown.
Some individual herd members spend disproportionately
more time within riparian areas (Roath and Krueger, 1982;
Howery et al., 1996, 1998), but it is possible that in their
absence and without diligent herding the desirable habitat in
the vacated riparian area would simply be reoccupied by
other individuals within the herd. This is what occurred in
Scotland when Hunter (1960) selectively culled sheep that
had occupied the preferred grazing areas within a pasture.
Hunter speculated that the sheep removed from the preferred
grazing area had been a high-ranked group, and after their
removal their home range was occupied by a lower-ranked
group. In northern England, Rawes and Welch (1969) found
that stocking rate reductions of sheep did not alleviate grazing
pressure on the better sites and only reduced use of the
less desirable areas. Many similar examples exist in the western
United States, where reducing numbers of livestock has
done very little to redistribute grazing pressure away from
riparian zones.
Selective culling has longer-lasting results when all females
in a subgroup are removed. This ensures that
reoccupation can only occur by dispersing females rather
than reproduction by females that escaped culling. Selective
culling will probably not be effective if outside animals are
introduced into the herd. Translocated animals often do not
assimilate into the subgroups of the existing population and
instead establish new home ranges. Translocated animals
could occupy the habitat vacated by selective culling. Similarly,
selective culling has little chance of success if ranchers
do not select replacement females from animals reared in the
same pasture from which animals were selectively culled.
Replacements reared elsewhere that cannot return to their
natal home range will probably establish their home ranges in
the vacated habitat. Finally, livestock managers using selective
culling should also make certain that replacement females
selected from the herd were not raised by cows whose
home ranges included the targeted removal area. Otherwise,
the replacements will likely perpetuate the foraging pattern of
their culled mothers.
Supplemental Feeding.Many cow-calf producers have
routinely used knowledge of herd social structures and hierarchies
to improve the uniform delivery of supplements.
Cattle herds should be separated into similar age and body
condition classes when possible. This will reduce overconsumption
by older, heavier, more-dominant animals. Research
results from Bowman et al. (1999) suggest that even
2- and 3-yr-olds should be separated because 2-yr-old cows
did not receive adequate supplement when pastured with 3-
yr-old cows. Overconsumption of self-fed supplements by a
few older, more-dominant animals may be reduced by increasing