ENVIRONMENTAL CONSEQUENCES in rocky mountain coniferous ...

ROAC HANAGEFIENT
More than any other single facet of forest management, road construction and
the post-logging management of those roads has been reported as a problem in elk
management and in grizzly bear management. During the 19601s, greatly accelerated
timber harvest on Kational Forests, and an expanding network of new roads, made elk
more vulnerable to hunters and harassment (Wyoming Forest Study Team 1971).
Unwanted side effects included reduction in the length and quality of hunting sea-
sons, loss of habitat, overharvest and declines in elk populations (Janson 1973;
Stankey and others 1973; Thiessen 1976; Hershcy and Leege 1976; Coggins 1976; Perry
and Overly 1976).
In recent years it has been repeatedly confirmed that elk avoid habitat adja-
cent to travel 1 ed roads. The width of the area avoided depends on the kind and
amount of traffic and the available cover. Apparently, elk will become accustomed
to the consistent movement of highway traffic and are most disturbed near secondary
roads with slow-moving or erratic and noisy traffic and people outside vehicles
(Eurbridge and Neff 1976; Ward 1976). Habitat adjacent to primitive and dirt roads
is not as persistently avoided, possibly because it is disturbed less often (Perry
and Overly 1976, Rost and Bailey 1979). Elk avoidance of any road is greatest in
nlcadows and openings and least in heavy or dense cover (Perry and Overly 1976, Lyon
1975).
Unlike the temporary displacement of elk by logging activity, avoidance of
habitat adjacent to roads is significant and continuous while the roads are open to
vehicles. Perry and Overly (1976) pointed out that more than 2.6 km2 (640 acres) of
habitat can be affected by 1.6 km (one mile) of road, and Lyon (1979a) calculated
that as little as 1.86 km/km2 (3 miles per section) of open road can terminate elk
use. In many circumstances, elk can retreat to undisturbed habitat, but this avoid-
ance response may entail some nutritional risk if an expanding road system restricts
animals to substandard habitat (Rost and Bailey 1979).
In addi ti on to obvious mi ti gati on through road closures , 1 t has been recom-
mended that roads be located in timber rather than openings (Ward 1976; Black and
others lW6), designed to have minimum cuts and fills, no long straight stretches,
the smallest possible widths, and construction features facilitating effective
closure (Black and others 1976; Lyon 1975).
Cespite the volume of information showing negative elk response to open roads,
the expected positive response following road closure has not been fully investi-
gated. Marcum (1975) reported increased elk use followin closure of logging roads
in the Sapphire Elountains in flontana; Burbridge and leff 71 976) detected increased
use in the closed unit of paired areas; and Lyon (1979b) reported that elk use of a
logged drainage returned to prelogging levels after road closure. In both of the
1 atter studies, weather was considered an important factor influencing elk movement.
Several investigators have displayed an interest in elk and hunter response to
road c1 osures during the hunt4 ng season. Such travel restrictions have general ly
been successful in improving the perceived quality of the hunt (Coggins 1976; Gasile
and Lonner 1979; Stankey and others 1973). Closures, however, have not resulted in
the creation of refuge areas (Eurbridge and Neff 1976; Coggins 1976) with the possi-
ble exception that elk emigration from areas of sparse cover is reduced when hunters
are 1 imited to foot travel (Basile and Lonner 1979).