History of Portneuf WMA

History

Portneuf WMA has a history as mule deer winter range, pasture for domestic livestock, and dry- land agriculture prior to acquisition by Idaho Fish and Game. The first and largest purchase of land was 2,820 acres in 1970. Three smaller parcels were purchased by 1974 to achieve the present area of 3,104 acres. An additional 802 acres of BLM land are managed for wildlife values under a cooperative agreement for a total of 3,906 acres.

The area has been previously referred to as the Portneuf Winter Range Wildlife Management Area and the Portneuf Game Range. Informally it has often been called Robber’s Roost in reference to a gold shipment robbery that occurred in the vicinity during the 19th Century. Prior to settlement, the area of Portneuf Canyon was known as a dangerous stretch to pass through on a stagecoach due to the gangs of bandits frequenting the area.

A well-publicized robbery involved the theft of $60,000 in gold from a Virginia City stage coach, and rumored to have been hidden in what became known as Robber’s Roost. However, the area’s historical use as mule deer winter range is its most significant value and it is now designated the Portneuf Wildlife Management Area.

Since its acquisition, Portneuf WMA has been managed for mule deer winter range and public hunting, although it is also increasingly visited for wildlife appreciation and other outdoor recreation. Wild turkeys were introduced in 2002 at three locations within Big Game Management Unit 71 and within the Portneuf WMA landscape. One release site was Robbers Roost Canyon within the WMA boundary. Populations have grown and controlled hunting has been permitted since 2004. Depredation issues have occasionally developed relating to wintering deer and more recently turkey. During especially harsh conditions, all human entry onto the WMA has been restricted. Emergency winter feeding of mule deer has been undertaken within the Portneuf WMA landscape when determined appropriate by the Regional Winter Feeding Advisory Committee. Vehicle collisions can become significant during harsh winter conditions.

There has been no domestic livestock grazing. Interior and extraneous fences have been removed. Boundary fences have been relocated on property lines, replaced, repaired or in some cases replaced by markers only. Sections of fence, which inhibit big game movements, have been removed or modified.

Road work has been completed in coordination with Bannock County and adjacent landowners. Several interior roads have been closed to motorized vehicles to reduce risk to area users and reduce disturbance. Water bars have been installed and maintained on remaining motorized trails to reduce erosion. Some established road sections have been graded and graveled as needed. Fenced parking areas have been maintained near four access points with the most recent completed in 2012. These provide off-road parking and facilitate non-motorized access when the interior roads are closed to motorized traffic.

Numerous techniques are available to manage vegetation, each depending on the objectives, limitations, potential natural vegetation, and present state of a given site. Soils and climate are the primary constraints that determine the long-term potential for the plant species diversity and abundance on a site, which in turn determine the presence and carrying capacity of animal species there (Bookhout 1994). The habitat management program for Portneuf WMA will apply techniques such as planting desirable species; chemical, biological, and mechanical control of less desirable species including noxious weeds; fertilization of selected areas; prescribed burns; and exclusion of livestock to reduce competition for forage. Any of these techniques may be applied when appropriate to achieve site-specific objectives, although vegetation management often requires no intervening action other than permitting natural ecological processes to occur.

Planting desirable species on Portneuf WMA improves its value as deer winter range. Bitterbrush and Hobble Creek sagebrush remain the primary species planted, although others may be included in future plantings. Sagebrush and bitterbrush seed are collected annually on the Portneuf WMA. This seed is grown to bare root seedlings by USFS Lucky Peak Nursery and planted throughout the Southeast Region to re-establish burned areas or enhance diminished brush stands. Vegetation monitoring has been carried out periodically to evaluate the long-term effects of forage manipulation for wintering mule deer.

The Portneuf WMA is managed along with three other WMAs by the Regional Wildlife Biologist assigned to the East Habitat District of the Southeast Region under the supervision of the Regional Habitat Manager. The habitat management program on Portneuf WMA is focused primarily on vegetation management in order to carry out the mission of enhancing mule deer winter range and providing quality habitat for other wildlife and fish.