Butts (1992) describes this document and another published by Koehler and Brittel in 1991 as "the most comprehensive guidelines to maintain or improve lynx habitat" (31). The authors qualify their recommendations with this statement on the title page:

"These timber harvest and road management guidelines were developed by the Washington Department of Wildlife and the staff of the Okanagan National Forest, specfically for lynx in the Okanagan region of Washington".

Indeed, the widespread application of similar recommendations published in Koehler and Brittel 1991 has been questioned due to the following (e.g., J. Halfpenny, pers. comm.):
- focus is on burned forests/habitats;
- unclear that recommendations can be extrapolated to the drier sites of the Rocky Mountains.

In addition to proposing management recommendations, this paper describes perhaps the most extensive field research on lynx in the western U.S. The comments that follow relate first to the field research, and then to the management recommendations.

"Field studies on lynx were conducted on a 448 square mile (1,161 sq km) area in Okanagan County of northcentral Washington. The study area was located about 30 miles northwest of Omak... The area is managed by the U.S. Forest Service and Washington Department of Natural Resources." (4)

"Twenty-five lynx were captured 40 times. These included 12 males, 12 females, and 1 individual for which sex was not determined. All were adults. Movement patterns of radio-collared lynx and snow tracking indicated that not all lynx on the study area were captured." (9)

"A total of 74 locations were obtained from 23 radio instrumented lynx... Monitoring of radio collared lynx revealed that at the time of initial capture 10 (76%) of were resident animals and 3 (12%) were transients. The status of three individuals was not determined because of insufficient data." (10)

Results

Home Ranges and Densities

"Home range of males varied in size from 7.9 to 42.7 square miles (20.5 to 110.6 sq km) and for females from 3.6 to 45.1 square miles (9.3 to 116.8 sq km). Mean home range size of males and females combined was 24.3 square miles (62.9 sq km)..." (46)

"An estimated 23 resident lynx occurred on the study area each year during the three-year study... lynx density was therefore calculated to be one resident adult per 19.5 square miles (50.5) sq km) or two per base figure of 100 sq km." (61)

Reproduction and Mortality

"There was no evidence that any of the radio instrumented females had litters during this study... Snow tracking of seven females in the early fall indicated no kittens accompanying the females. Limited reproduction did occur on the study area however, as snow tracking individuals indicated that unmarked adult females were accompanied by kittens. Four kittens were produced during the three year study." (70-71)

"The annual mortality rate (Trent and Rongstad 1974)... of radio-collared lynx, averaged 11.3 percent (21%?) and ranged from 0 to 29.1 percent (34.3%?). Three females and one male died from natural causes during the study. The causes included starvation and predation with the two undetermined." (71)

"Three resident lynx [two males and one female] were known to have emigrated from the study area... Annual emigration rates for all lynx averaged 21.9 percent (31.6%?)." (72)

"Kitten mortality ranged from 65 to 95 percent and was believed to be the primary cause of reduced winter recruitment in Alberta (Brand and Keith 1979)." (76)

"... it would appear that lynx numbers in Washington oscillate around 200 animals with 150 being on the low end of the spectrum and 300+ being on the high end." (84)

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Notable excerpts regarding management include the following.

Denning Cover, Key Characteristics:
- dominant 150 years or older sub-alpine fir or Englemann spruce
- down material
- minimal human disturbance
- adjacent to travel or forage/hiding/thermal-stalking cover on 50% of its edge
- at least 5 acres in size, interspersed among other cover types

Travel Cover, Key Characteristics:
- contiguous to areas of forage/hiding/thermal-stalking cover
- vegetation greater than 6 ft. high
- > 100 stems per acre, unless significant down material or bushy trees are present

Forage/hiding/thermal-stalking Cover, Key Characteristics:
- coniferous stands are at least 75% lodgepole pine
- trees and shrubs are at least 6 feet tall
- densely stocked, sapling trees
- down material
- contiguous with travel cover.

Vegetative Manipulation:
- Managed stands should not exceed 40 acres in size
- Clearcuts should be limited to 20-40 acres in size.
- The width of openings should not exceed 1200 feet, less than 600 feet would be optimal.
- Openings should never exceed 30% of the land
- Down material and other woody debris should be left
- Lodgepole pine must be maintained and not converted to other commercial species
- Thinning will increase non-lynx cover areas
- Herbicides, if necessary, must be managed to minimize effects on hare habitats, should be species-specific
- Cattle grazing should be monitored to minimize effects on hare habitats
- Major ridges should be managed to for travel cover, with special emphasis on saddles.
- Travel cover corridors must be greater than 300 feet wide.
- Trees in harvested units should be six feet or taller, before adjacent areas are logged or thinned.

Recommended cover ratios for lynx habitat in Washington:
Denning 6%
Travel 30%
Forage/Hiding/Thermal-Stalking 30%
Non-lynx cover areas 33%

Road Management
- Minimize road construction, esp. main access roads
- Construct and maintain roads to minimum possible standards to discourage heavy use; the more primitive, the better.
- Destroy roads following logging operations... planting trees in the roadbed may be more effective to discourage snowmobile use...
-Construct deadend roads rather than loop roads to minimize public use disturbance.

o Hares reoccupy severely burned areas within 15 months (Keith and Surrendi 1971; 90), yet
o "Small mammal populations are drastically reduced immediately following clear cut operations" (90)
o Elimination of mature subalpine fir and Englemann spruce stands also may impact lynx... they are an important component of lynx habitat, especially during inclement winter weather, drought, or denning periods (91)