The size of the individual Indian reservation lands in the Northern Rockies, Maine, and Minnesota units is relatively small. As a result, we believe conservation of the lynx can be achieved by limiting the designation to the other lands in the proposal without including Tribal lands (see ``Relationship of Critical Habitat to Tribal Lands'' below).

The southern Rocky Mountains in Colorado, Utah, and southern Wyoming are disjunct from other lynx habitats in the United States and Canada. The nearest lynx population occurs in the Greater Yellowstone Area (GYA), which is a small, low density population also disjunct from other lynx populations and is unlikely to regularly supply dispersing lynx to the Southern Rockies. Native lynx were functionally extirpated [[Page 10861]]
from their historic range in Colorado and southern Wyoming by the time the lynx was listed as a threatened species under the Act in 2000. In 1999, the State of Colorado began an intensive effort to reintroduce lynx. Although it is too early to determine whether the introduction will result in a selfsustaining population, the reintroduced lynx have produced kittens and now are distributed throughout the lynx habitat in Colorado and southern Wyoming. These animals are not designated as an experimental population under section 10(j) of the Act. Although Colorado's reintroduction effort is an important step toward the recovery of lynx, we are not proposing revised critical habitat in the Southern Rockies because of the current uncertainty that a self sustaining lynx population will become established.

The Kettle Range in Washington historically supported lynx populations (Stinson 2001). However, although boreal forest habitat within the Kettle Range appears of high quality for lynx, there is no evidence that the Kettle Range is currently occupied by a lynx population nor has there been evidence of reproducing lynx in the Kettle Range in the past two decades (Koehler 2008).

Fuelsreduction projects in the WUI may degrade lynx habitat by reducing its ability to support snowshoe hares. For this reason, if WUI areas were designated as revised critical habitat, fuelsreduction projects may be impaired or delayed as a result of requirements under section 7(a)(2) of the Act, which could lead to reduced effectiveness of the fuelsreduction, and increased risk to human life and property. Mapped WUI areas can be viewed on the Internet at: ftp:// ftp2.fs.fed.us/incoming/r1/FWS/wui1milebufferoct06.pdf.

In addition to public comments received on this proposed rule, between the proposed and final rules, the Service will analyze the following for its relevance in revising critical habitat for lynx: (1) Comments received in response to our initiation of a 5year review for lynx; (2) a new study addressing effects of snowmobile trails on coyote movements within lynx home ranges (Kolbe et al. 2007, pp. 14091418); (3) a study on lynx prey selection (Squires and Ruggiero 2007, pp. 310 315); (4) new reports we have received on the numbers and distribution of lynx in some locations; (5) a newly released study on the effects of climate change on snowpack in western mountains and how that may affect lynx, snowshoe hares, and their habitats (Gonzalez et al. 2007); and (6) additional new studies (e.g., Knowles et al. 2006 and Danby and Hick 2007) that may provide insight on changes to lynx habitat. If necessary and appropriate, revisions to this proposed rule will be made to address this information. We will also be revising the economic analysis and environmental assessment prepared for the previous designation and providing drafts of the new economic analysis and environmental assessment to the public before finalizing this proposal.

On the basis of public comment, during the development of the revised final rule we may find, among other things, that areas proposed are not essential to the conservation of the species, are appropriate for exclusion under section 4(b)(2) of the Act, or are not appropriate for exclusion. In all of these cases, this information will be incorporated into the revised final designation. Further, we may find as a result of public comments that areas not proposed should also be designated as critical habitat. Final management plans that address the conservation of the lynx must be submitted to us during the public comment period so that we can take them into consideration when making our final critical habitat determination.

You may submit your comments and materials concerning this proposed rule by one of the methods listed in the ADDRESSES section. We will not accept comments sent by email or fax or to an address not listed in the ADDRESSES section. We will not accept anonymous comments; your comment must include your first and last name, city, State, country, and postal (zip) code. Finally, we will not consider handdelivered comments that we do not receive, or mailed comments that are not postmarked, by the date specified in the DATES section.

We will post your entire commentincluding your personal identifying informationon http://www.regulations.gov. If you provide personal identifying information in addition to the required items specified in the previous paragraph, such as your street address, phone number, or email address, you may request at the top of your document that we withhold this information from public review. However, we cannot guarantee that we will be able to do so.

Comments and materials we receive, as well as supporting documentation we used in preparing this revised proposed rule, will be available for public inspection on http://www.regulations.gov, or by appointment, during normal business hours, at the U.S. Fish and Wildlife Service, Montana Ecological Services Office (see FOR FURTHER INFORMATION CONTACT). Maps of the proposed revised critical habitat are also available on the Internet at http://mountainprairie.fws.gov/ species/mammals/lynx/.

Background

It is our intent to discuss only those topics directly relevant to the designation of critical habitat in this proposed rule. For more information on the lynx refer to the final listing rule published in the Federal Register on March 24, 2000 (65 FR 16052), and the clarification of findings published in the Federal Register on July 3, 2003 (68 FR 40076).

Canada lynx are mediumsized cats, generally measuring 30 to 35 inches (in) (75 to 90 centimeters (cm)) long and weighing 18 to 23 pounds (8 to 10.5 kilograms) (Quinn and Parker 1987, Table 1). They have large, wellfurred feet and long legs for traversing snow; tufts on the ears; and short, blacktipped tails.

Lynx are highly specialized predators of snowshoe hare (Lepus americanus) (McCord and Cardoza 1982, p. 744; Quinn and Parker 1987, pp. 684685; Aubry et al. 2000, pp. 375378). Lynx and snowshoe hares are strongly associated with what is broadly described as boreal forest (Bittner and Rongstad 1982, p. 154; McCord and Cardoza 1982, p. 743; Quinn and Parker 1987, p. 684; Agee 2000, p. 39; Aubry et al. 2000, pp. 378382; Hodges 2000a, pp. 136140 and 2000b, pp. 183191; McKelvey et al. 2000b, pp. 211232). The predominant vegetation of boreal forest is conifer trees, primarily species of spruce (Picea spp.) and fir (Abies spp.) (ElliotFisk 1988, pp. 3435, 3742). In the contiguous United States, the boreal forest types transition to deciduous temperate forest in the Northeast and Great Lakes and to subalpine forest in the west (Agee 2000, pp. 4041). Lynx habitat can generally be described as moist boreal forests that have cold, snowy winters and a snowshoe hare prey base (Quinn and Parker 1987, p. 684685; Agee 2000, pp. 3947; Aubry et al. 2000, pp. 373375; Buskirk et al. 2000b, pp. 397405; Ruggiero et al. 2000, pp. 445447). In mountainous areas, the boreal forests that lynx use are characterized by scattered moist forest types with high hare densities in a matrix of other habitats (e.g., hardwoods, dry forest, nonforest) with low hare densities. In these areas, lynx incorporate the matrix habitat (nonboreal forest habitat elements) into their home ranges and use it for traveling between patches of boreal forest that support high hare densities where most foraging occurs.

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Snow conditions also determine the distribution of lynx (Ruggiero et al. 2000, pp. 445449). Lynx are morphologically and physiologically adapted for hunting snowshoe hares and surviving in areas that have cold winters with deep, fluffy snow for extended periods. These adaptations provide lynx a competitive advantage over potential competitors, such as bobcats (Lynx rufus) or coyotes (Canis latrans) (McCord and Cardoza 1982, p. 748; Buskirk et al. 2000a, pp. 8695; Ruediger et al. 2000, p. 111; Ruggiero et al. 2000, pp. 445, 450). Bobcats and coyotes have a higher foot load (more weight per surface area of foot), which causes them to sink into the snow more than lynx. Therefore, bobcats and coyotes cannot efficiently hunt in fluffy or deep snow and are at a competitive disadvantage to lynx. Longterm snow conditions presumably limit the winter distribution of potential lynx competitors such as bobcats (McCord and Cardoza 1982, p. 748) or coyotes.

Lynx Habitat Requirements

Because of the patchiness and temporal nature of high quality snowshoe hare habitat, lynx populations require large boreal forest landscapes to ensure that sufficient high quality snowshoe hare habitat is available and to ensure that lynx may move freely among patches of suitable habitat and among subpopulations of lynx. Populations that are composed of a number of discrete subpopulations, connected by dispersal, are called metapopulations (McKelvey et al. 2000c, p. 25). Individual lynx maintain large home ranges (reported as generally ranging between 12 to 83 mi\2\ (31 to 216 km\2\)) (Koehler 1990, p. 847; Aubry et al. 2000, pp. 382386; Squires and Laurion 2000, pp. 342 347; Squires et al. 2004b, pp. 1316, Table 6; Vashon et al. 2005a, pp. 711). The size of lynx home ranges varies depending on abundance of prey, the animal's gender and age, the season, and the density of lynx populations (Koehler 1990, p. 849; Poole 1994, pp. 612616; Slough and Mowat 1996, pp. 951, 956; Aubry et al. 2000, pp. 382386; Mowat et al. 2000, pp. 276280; Vashon et al. 2005a, pp. 910). When densities of snowshoe hares decline, for example, lynx enlarge their home ranges to obtain sufficient amounts of food to survive and reproduce.

In the contiguous United States, the boreal forest landscape is naturally patchy and transitional because it is the southern edge of the boreal forest range. This generally limits snowshoe hare populations in the contiguous United States from achieving densities similar to those of the expansive northern boreal forest in Canada (Wolff 1980, pp. 123128; Buehler and Keith 1982, pp. 24, 28; Koehler 1990, p. 849; Koehler and Aubry 1994, p. 84). Additionally, the presence of more snowshoe hare predators and competitors at southern latitudes may inhibit the potential for highdensity hare populations (Wolff 1980, p. 128). As a result, lynx generally occur at relatively low densities in the contiguous United States compared to the high lynx densities that occur in the northern boreal forest of Canada (Aubry et al. 2000, pp. 375, 393394) or the densities of species such as the bobcat, which is a habitat and prey generalist.

Lynx are highly mobile and generally move long distances (greater than 60 mi (100 km)) (Aubry et al. 2000, pp. 386387; Mowat et al. 2000, pp. 290294). Lynx disperse primarily when snowshoe hare populations decline (Ward and Krebs 1985, pp. 28212823; O'Donoghue et al. 1997, pp. 156, 159; Poole 1997, pp. 499503). Subadult lynx disperse even when prey is abundant (Poole 1997, pp. 502503), presumably to establish new home ranges. Lynx also make exploratory movements outside their home ranges (Aubry et al. 2000, p. 386; Squires et al. 2001, pp. 1826).

The boreal forest landscape is naturally dynamic. Forest stands within the landscape change as they undergo succession after natural or humancaused disturbances such as fire, insect epidemics, wind, ice, disease, and forest management (ElliotFisk 1988, pp. 4748; Agee 2000, pp. 4769). As a result, lynx habitat within the boreal forest landscape is typically patchy because the boreal forest contains stands of differing ages and conditions, some of which are suitable as lynx foraging or denning habitat (or will become suitable in the future due to forest succession) and some of which serve as travel routes for lynx moving between foraging and denning habitat (McKelvey et al. 2000a, pp. 427434; Hoving et al. 2004, pp. 290292).

Snowshoe hares comprise a majority of the lynx diet (Nellis et al. 1972, pp. 323325; Brand et al. 1976, pp. 422425; Koehler 1990, p. 848; Apps 2000, pp. 358359, 363; Aubry et al. 2000, pp. 375378; Mowat et al. 2000, pp. 267268; von Kienast 2003, pp. 3738; Squires et al. 2004b, p. 15, Table 8). When snowshoe hare populations are low, female lynx produce few or no kittens that survive to independence (Nellis et al. 1972, pp. 326328; Brand et al. 1976, pp. 420, 427; Brand and Keith 1979, pp. 837838, 847; Poole 1994, pp. 612616; Slough and Mowat 1996, pp. 953958; O'Donoghue et al. 1997, pp. 158159; Aubry et al. 2000, pp. 388389; Mowat et al. 2000, pp. 285287). Lynx prey
opportunistically on other small mammals and birds, particularly during lows in snowshoe hare populations, but alternate prey species may not sufficiently compensate for low availability of snowshoe hares, resulting in reduced lynx populations (Brand et al. 1976, pp. 422425; Brand and Keith 1979, pp. 833834; Koehler 1990, pp. 848849; Mowat et al. 2000, pp. 267268).

In northern Canada, lynx populations fluctuate in response to the cycling of snowshoe hare populations (Hodges 2000a, pp. 118123; Mowat et al. 2000, pp. 270272). Although snowshoe hare populations in the northern portion of their range show strong, regular population cycles, these fluctuations are generally much less pronounced in the southern portion of their range in the contiguous United States (Hodges 2000b, pp. 165173). In the contiguous United States, the degree to which regional local lynx population fluctuations are influenced by local snowshoe hare population dynamics is unclear. However, it is anticipated that because of natural fluctuations in snowshoe hare populations, there will be periods when lynx densities are extremely low.

Because lynx population dynamics, survival, and reproduction are closely tied to snowshoe hare availability, snowshoe hare habitat is a component of lynx habitat. Lynx generally concentrate their foraging and hunting activities in areas where snowshoe hare populations are high (Koehler et al. 1979, p. 442; Ward and Krebs 1985, pp. 28212823; Murray et al. 1994, p. 1450; O'Donoghue et al. 1997, pp. 155, 159160 and 1998, pp. 178181). Snowshoe hares are most abundant in forests with dense understories that provide forage, cover to escape from predators, and protection during extreme weather (Wolfe et al. 1982, pp. 665669; Litvaitis et al. 1985, pp. 869872; Hodges 2000a, pp. 136 140 and 2000b, pp. 183195). Generally, hare densities are higher in regenerating, earlier successional forest stages because they have greater understory structure than mature forests (Buehler and Keith 1982, p. 24; Wolfe et al. 1982, pp. 665669; Koehler 1990, pp. 847848; Hodges 2000b, pp. 183195; Homyack 2003, p. 63, 141; Griffin 2004, pp. 8488). However, snowshoe hares can be abundant in mature forests with dense understories (Griffin 2004, pp. 5354).

Within the boreal forest, lynx den sites are located where coarse woody debris, such as downed logs and windfalls, provides security and thermal cover for lynx kittens (McCord and Cardoza 1982, pp. 743744; Koehler
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1990, pp. 847849; Slough 1999, p. 607; Squires and Laurion 2000, pp. 346347; Organ 2001). The amount of structure (e.g., downed, large, woody debris) appears to be more important than the age of the forest stand for lynx denning habitat (Mowat et al. 2000, pp. 1011). Future of Lynx Habitat

In 2003, we determined that climate change was not a threat to lynx because the best available science we had at that time (Hoving 2001) was too uncertain in nature (68 FR 40083). Since that time, new information on regional climate changes and potential effects to lynx habitat has been developed (e.g., Gonzalez et al. 2007, entire; Knowles et al. 2006, pp. 45454559; Danby and Hick 2007, pp. 358359) that suggests that climate change may be an issue of concern for the future conservation of lynx. This information, combined with the information in Hoving 2001, still needs to be evaluated further to determine how climate change might affect lynx and lynx habitat. We are evaluating this information in the 5year review we are conducting for lynx.

At this time, we find it appropriate to propose revised critical habitat in areas that are occupied and currently contain the physical and biological features essential to the conservation of the lynx. Revisions to the critical habitat designation may be necessary in the future to accommodate shifts in the occupied range of the lynx. To the extent lynx distribution and habitat is likely to shift upward in elevation within its currently occupied range as the temperatures increase (Gonzalez et al. 2007, pp. 7, 1314,19), the proposed revised critical habitat units include the highestelevation habitats that lynx would be able to use in that event.

Previous Federal Actions

For more information on previous Federal actions concerning the lynx, refer to the final listing rule published in the Federal Register on March 24, 2000 (65 FR 16052), the clarification of findings published in the Federal Register on July 3, 2003 (68 FR 40076), and the final rule designating critical habitat for lynx published in the Federal Register on November 9, 2006 (71 FR 66007). On July 20, 2007, the Service announced that we would review the November 9, 2006 final rule after questions were raised about the integrity of scientific information used and whether the decision made was consistent with the appropriate legal standards. Based on our review of the previous final critical habitat designation, we have determined that it is necessary to revise critical habitat, and this rule proposes those revisions. On January 15, 2008, the U.S. District Court for the District of Columbia issued an order stating the Service's deadlines for a proposed rule for revised critical habitat by February 15, 2008, and a final rule for revised critical habitat by February 15, 2009.

Critical Habitat

Critical habitat is defined in section 3 of the Act as: (1) The specific areas within the geographical area occupied by a species, at the time it is listed in accordance with the Act, on which are found those physical or biological features
(a) Essential to the conservation of the species and
(b) That may require special management considerations or protection; and
(2) Specific areas outside the geographical area occupied by a species at the time it is listed, upon a determination that such areas are essential for the conservation of the species.

Conservation, as defined under section 3 of the Act, means the use of all methods and procedures that are necessary to bring any endangered species or threatened species to the point at which the measures provided under the Act are no longer necessary.

Critical habitat receives protection under section 7 of the Act through the prohibition against Federal agencies carrying out, funding, or authorizing activities that result in the destruction or adverse modification of critical habitat. Section 7 of the Act requires consultation on Federal actions that may affect critical habitat. The designation of critical habitat does not affect land ownership or establish a refuge, wilderness, reserve, preserve, or other conservation area. Such designation does not allow the government or public to access private lands. Such designation does not require implementation of restoration, recovery, or enhancement measures by the landowner. Where the landowner seeks or requests Federal agency funding or authorization of an activity that may affect a listed species or critical habitat, the consultation requirements of section 7 would apply. Nonetheless, even in the event a project with a Federal nexus may result in the destruction or adverse modification of critical habitat, the landowner's obligation is not to restore or recover the species, but to implement reasonable and prudent alternatives to avoid destruction or adverse modification of critical habitat.

For inclusion in a critical habitat designation, habitat within the geographical area occupied by the species at the time it was listed must contain physical and biological features that are essential to the conservation of the species. Consistent with this requirement, the Service identifies, to the extent known using the best scientific data available, habitat areas on which are found the physical and biological features essential, as defined at 50 CFR 424.12(b), and identifies the quantity and spatial arrangement of such areas to ensure that the areas designated as critical habitat are essential for the conservation of the species. Occupied habitat that contains the physical and biological features essential to the conservation of the species meets the definition of critical habitat only if those features may require special management considerations or protection.

Under the Act, we can designate unoccupied areas as critical habitat only when we determine that the best available scientific data demonstrate that the designation of that area is essential to the conservation of the species.

Section 4 of the Act requires that we designate critical habitat on the basis of the best scientific and commercial data available. Further, our Policy on Information Standards Under the Endangered Species Act (published in the Federal Register on July 1, 1994 (59 FR 34271)), the Information Quality Act (section 515 of the Treasury and General Government Appropriations Act for Fiscal Year 2001 (Pub. L. 106554; H.R. 5658)), and our associated Information Quality Guidelines provide criteria, establish procedures, and provide guidance to ensure that our decisions are based on the best scientific data available. These documents require our biologists, to the extent consistent with the Act and with the use of the best scientific data available, to use primary and original sources of information as the basis for recommendations to designate critical habitat.

When we are determining which areas should be proposed as critical habitat, our primary source of information is generally the information developed during the listing process for the species. Additional information sources may include the recovery plan for the species, articles in peerreviewed journals, conservation plans developed by States and counties, scientific status surveys and studies, biological assessments, or other unpublished materials and expert opinion or personal knowledge.

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Habitat is often dynamic, and species may move from one area to another over time. Furthermore, we recognize that designation of critical habitat may not include all of the habitat areas that we may eventually determine, based on scientific data not now available to the Service, are necessary for the recovery of the species. For these reasons, a critical habitat designation does not signal that habitat outside the designated area is unimportant or may not be required for recovery of the species.

Areas that support populations, but are outside the critical habitat designation, may continue to be subject to conservation actions we implement under section 7(a)(1) of the Act. They are also subject to the regulatory protections afforded by the section 7(a)(2) jeopardy standard, as determined on the basis of the best available scientific information at the time of the agency action. Federally funded or permitted projects affecting listed species outside their designated critical habitat areas may still result in jeopardy findings in some cases. Similarly, critical habitat designations made on the basis of the best available information at the time of designation will not control the direction and substance of future recovery plans, habitat conservation plans (HCPs), section 7 consultation, or other species conservation planning efforts if new information calls for a different outcome.

Methods

As required by section 4(b)(2) of the Act, we use the best scientific data available to determine areas occupied at the time of listing that contain the features essential to the conservation of the lynx. We have reviewed the approach to the conservation of the lynx provided in its recovery outline (Service 2005, entire) and information from State, Federal, and Tribal agencies, and from academia and private organizations that have collected scientific data on lynx. The Service also obtained information about critical habitat for lynx in 2005 and 2006 during development of rules for lynx critical habitat. The Service also initiated a 5year review for the lynx on April 18, 2007 (72 FR 19549). Information gathered for that purpose will be used in completing our final designation.

We have used information we reviewed for the prior designation of critical habitat, including data in reports submitted by researchers holding recovery permits under section 10(a)(1)(A) of the Act, research published in peerreviewed articles and presented in academic theses, agency reports, unpublished data, and various Geographic Information System (GIS) data layers (e.g., land cover type information, land ownership information, snow depth information, topographic information, locations of lynx obtained from radio or Global Positioning System (GPS) collars, and locations of lynx confirmed via deoxyribonucleic acid (DNA) analysis or other verified records).

Primary Constituent Elements

In accordance with section 3(5)(A)(i) of the Act and the regulations at 50 CFR 424.12(b), in determining which areas occupied at the time of listing to propose as critical habitat, we consider the physical and biological features that are essential to the conservation of the species to be the primary constituent elements (PCEs) laid out in the appropriate quantity and spatial arrangement for conservation of the species. In general, PCEs include, but are not limited to: (1) Space for individual and population growth and for normal behavior;
(2) Food, water, air, light, minerals, or other nutritional or physiological requirements;
(3) Cover or shelter;
(4) Sites for breeding, reproduction, or rearing (or development) of offspring; and
(5) Habitats that are protected from disturbance or are representative of the historic, geographical, and ecological distributions of a species.

When considering the designation of critical habitat, we must focus on the principal biological or physical constituent elements within the defined area that are essential to the conservation of the species. As previously stated, we consider the physical and biological features that are essential to the conservation of the species to be the primary constituent elements (PCEs) laid out in the appropriate quantity and spatial arrangement for conservation of the species. As such, we derive the PCEs required for lynx from its biological needs. The area proposed for designation as revised critical habitat provides boreal forest habitat for breeding, nonbreeding, and dispersing lynx in
metapopulations across their range in the contiguous United States. We are not proposing any areas solely because they provide habitat for dispersing animals because the areas we are proposing serve a variety of functions that include acting as a source of dispersing animals and providing habitat that serves as travel corridors to facilitate dispersal and exploratory movements. The primary constituent elements and therefore the resulting physical and biological features essential for the conservation of the species were determined from studies of lynx and snowshoe hare ecology.
Space for Individual and Population Growth and Normal BehaviorBoreal Forest Landscapes

Lynx populations respond to biotic and abiotic factors at different scales. At the regional scale, snow conditions, boreal forest, and competitors (especially bobcat) influence the species' range (Aubry et al. 2000, pp. 378380; McKelvey et al. 2000b, pp. 242253; Hoving et al. 2005, p. 749). At the landscape scale within each region, natural and humancaused disturbance processes (e.g., fire, wind, insect infestations, and forest management) influence the spatial and temporal distribution of lynx populations by affecting the distribution of good habitat for snowshoe hares (Agee 2000, pp. 4773; Ruediger et al. 2000, pp. 13, 22, 26, 73). At the standlevel scale, quality, quantity, and juxtaposition of habitats influence home range size, productivity, and survival (Aubry et al. 2000, pp. 380390; Vashon et al. 2005a, pp. 911). At the substand scale, spatial distribution, abundance of prey, and microclimate influence movements, hunting behavior, and den and resting site locations.

All of the components of the physical and biological features of proposed revised critical habitat for lynx are found within large landscapes in what is broadly described as the boreal forest or cold temperate forest (Frelich and Reich 1995, p. 325; Agee 2000, pp. 43 46). The primary constituent element is broadly described as the boreal forest landscape. In the contiguous United States, the boreal forest is more transitional than the true boreal forest of northern Canada and Alaska (Agee 2000, pp. 4346). This difference is because the boreal forest is at its southern limits in the contiguous United States, where it transitions to deciduous temperate forest in the Northeast and Great Lakes and subalpine forest in the west (Agee 2000, pp. 4346). We use the term ``boreal forest'' because it generally encompasses most of the vegetative descriptions of the transitional forest types that comprise lynx habitat in the contiguous United States (Agee 2000, pp. 4041).

At a regional scale, lynx habitat exists in areas that generally support deep snow throughout the winter and boreal forest vegetation types (see below for more detail). In eastern North America, [[Page 10865]]
lynx distribution is strongly associated with areas of deep snowfall (greater than 105 in (268 cm) of mean annual snowfall) and 40 mi\2\ (100 km\2\) landscapes with a high proportion of regenerating forest (Hoving 2001, pp. 75, 143). The broad geographic distribution of lynx in eastern North America is most influenced by snowfall, but within areas of similarly deep snowfall, measures of forest succession become more important factors in determining lynx distribution (Hoving et al. 2004, p. 291).

Boreal forests used by lynx are cool, moist, and dominated by conifer tree species, primarily spruce and fir (Agee 2000, pp. 4046; Aubry et al. 2000, pp. 378383; Ruediger et al. 2000, pp. 43, 48, 4 11, 425, 426, 429, 430). Boreal forest landscapes used by lynx are a heterogeneous mosaic of vegetative cover types and successional forest stages created by natural and humancaused disturbances (McKelvey et al. 2000a, pp. 426, 434). Periodic vegetation disturbances stimulate development of dense understory or early successional habitat for snowshoe hares (Ruediger et al. 2000, pp. 13, 14, 74, 75). In Maine, lynx were positively associated with landscapes clearcut 15 to 25 years previously (Hoving et al. 2004, p. 291).

The overall quality of the boreal forest landscape matrix and the juxtaposition of stands in suitable condition within that landscape is important for both lynx and snowshoe hares in that it influences connectivity or movements between suitable stands, availability of food and cover, and spatial structuring of populations or subpopulations (Hodges 2000b, pp. 181195; McKelvey et al. 2000a, pp. 431432; Walker 2005, p. 79). For example, lynx foraging habitat must be near denning habitat to allow females to adequately provide for dependent kittens, especially when the kittens are relatively immobile. In northcentral Washington, hare densities were higher in landscapes with an abundance of dense boreal forest interspersed with small patches of open habitat, in contrast to landscapes composed primarily of open forest interspersed with few dense vegetation patches (Walker 2005, p. 79). Similarly, in northwest Montana, connectivity of dense patches within the forest matrix benefited snowshoe hares (Ausband and Baty 2005, p. 209). In mountainous areas, lynx appear to prefer flatter slopes (Apps 2000, p. 361; McKelvey et al. 2000d, p. 333; von Kienast 2003, p. 21, Table 2; Maletzke 2004, pp. 1718).

Individual lynx require large portions of boreal forest landscapes to support their home ranges and to facilitate dispersal and exploratory travel. The size of lynx home ranges is believed to be strongly influenced by the quality of the habitat, particularly the abundance of snowshoe hares, in addition to other factors such as gender, age, season, and density of the lynx population (Aubry et al. 2000, pp. 382385; Mowat et al. 2000, pp. 276280). Generally, females with kittens have the smallest home ranges while males have the largest home ranges (Moen et al. 2004, p. 11). Reported home range size varies from 12 mi\2\ (31 km\2\) for females and 26 mi\2\ (68 km\2\) for males in Maine (Vashon et al. 2005a, p. 7), 8 mi\2\ (21 km\2\) for females and 119 mi\2\ (307 km\2\) for males in Minnesota (Moen et al. 2005, p. 12), and 34 mi\2\ (88 km\2\) for females and 83 mi\2\ (216 km\2\) for males in northwest Montana (Squires et al. 2004b, pp. 1516).

The dynamic nature of boreal forest landscapes means that lynx home ranges will incorporate a variety of forest stands that are in different stages of succession and have differing potential to produce prey. In addition, due to the naturally marginal nature of lynx habitat within the DPS, the moist boreal forest types that snowshoe hares prefer often occur in patches dissected or surrounded by matrix habitat. Lynx use the matrix habitat primarily as travel routes between foraging areas and denning areas. Although they are not dependent on the specific vegetative condition of these habitats (i.e., they are not sensitive to forest management practices), the importance of these areas as travel routes makes them necessary habitat components for lynx.
Forest Type Associations

Maine

Lynx are more likely to occur in 40 mi\2\ (100 km\2\) landscapes with regenerating forest, and less likely to occur in landscapes with recent clearcut or partial harvest, (Hoving et al. 2004, pp. 291292). Lynx in Maine select softwood (spruce and fir) dominated, regenerating stands (Vashon et al. 2005a, p. 8). Regenerating stands used by lynx generally develop 1530 years after forest disturbance and are characterized by dense horizontal structure and high stem density within a meter of the ground. These habitats support high snowshoe hare densities (Homyack 2003, p. 63; Fuller and Harrison 2005, pp. 716, 719; Vashon et al. 2005a, pp. 1011). At the stand scale, lynx in northwestern Maine selected older (11 to 26 yearold), tall (4.6 to 7.3 m (15 to 24 ft)), regenerating clearcut stands and older (11 to 21 yearold), partially harvested stands (A. Fuller, University of Maine, unpubl. data).

Minnesota

In Minnesota, lynx primarily occur in the Northern Superior Uplands Ecological Section of the Laurentian Mixed Forest Province. Historically, this area was dominated by red pine (Pinus resinosa) and white pine (Pinus strobus) mixed with aspen (Populus spp.), paper birch (Betula papyrifera), spruce, balsam fir (Abies balsamifera), and jack pine (Pinus banksiana) (Minnesota Department of Natural Resources [Minnesota DNR] 2003, p. 2).

Preliminary research suggests lynx in Minnesota generally use younger stands (less than 50 years) with a conifer component in greater proportion than their availability (R. Moen, University of Minnesota, unpubl. data). Lynx prefer predominantly upland forests dominated by red pine, white pine, jack pine, black spruce (Picea mariana), paper birch, quaking aspen (Populus tremuloides), or balsam fir (R. Moen, unpubl. data).

Washington

In the North Cascades in Washington, the majority of lynx occurrences were found above 1,250 m (4,101 ft) elevation (McKelvey et al. 2000b, p. 243 and 2000d, p. 321; von Kienast 2003, p. 28, Table 2; Maletzke 2004, p. 17). In this area, lynx selected Engelman spruce (Picea engelmanii)subalpine fir (Abies lasiocarpa) forest cover types in winter (von Kienast 2003, p. 28; Maletzke 2004, pp. 1617). Lodgepole pine (Pinus contorta) is a dominant tree species in the earlier successional stages of these climax cover types. Seral lodgepole stands contained dense understories and therefore received high use by snowshoe hares and lynx (Koehler 1990, pp. 847848; McKelvey et al. 2000d, pp. 332335).

Northern Rockies

In the Northern Rocky Mountains, the majority of lynx occurrences are associated with the Rocky Mountain Conifer Forest vegetative class (Kuchler 1964, p. 5; McKelvey et al. 2000b, p. 246) and occur above 1,250 m (4,101 ft) elevation (Aubry et al. 2000, pp. 378380; McKelvey et al. 2000b, pp. 243245). The dominant vegetation that constitutes lynx habitat in these areas is subalpine fir, Engelman spruce, and lodgepole pine (Aubry et al. 2000, p. 379; Ruediger et al. 2000, pp. 4 8410). As in the Cascades, lodgepole pine is an earlier successional stage of subalpine fir and Engelman spruce climax forest cover types. Greater Yellowstone Area

Lynx habitat in the GYA is similar to the Northern Rockies in that lynx
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occurrences are generally associated with the Rocky Mountain Conifer Forest vegetative class. The primary areas of lynx occurrence in this unit occur between 7,382 and 9,843 ft (2,250 and 3,000 m) elevation (Aubry et al. 2000, p. 379; McKelvey et al. 2000b, Figure 8.18). However, lynx are not limited to these elevation zones. The dominant vegetation that constitutes lynx habitat in these areas is subalpine fir, Engelman spruce, and lodgepole pine (Aubry et al. 2000, pp. 378 382; Ruediger et al. 2000, pp. 12, 13; Murphy et al. 2004, pp. 911). Lodgepole pine is an earlier successional stage of subalpine fir and Engelman spruce cover types. The vegetation characteristics in the GYA that support snowshoe hare populations (and form the basis for lynx populations) are typically found in a widely scattered mosaic of matrix habitat types (Murphy et al. 2005, p. 811; Hodges and Mills 2005, p. 6; Agee 2000, p. 48). In the GYA, lynx exploit hare populations in disjunct patches of mesic boreal forest that support relatively dense understories (Hodges and Mills 2005, pp. 46). In most cases, lynx home ranges in the GYA will by necessity incorporate habitat that is not typically considered lynx foraging habitat, and is used primarily for travel.
Food, Water, Air, Light, Minerals, Or Other Nutritional Or Physiological Requirements

a. Snowshoe Hares (Food)

Snowshoe hare density is the most important factor explaining the persistence of lynx populations (Steury and Murray 2004, p. 136). A minimum snowshoe hare density necessary to maintain a persistent, reproducing lynx population within the contiguous United States has not been determined, although Ruggiero et al. (2000, pp. 446447) suggested that at least 0.2 hares per acre (0.5 hares per hectare) may be necessary. Steury and Murray (2004, p. 137) modeled lynx and snowshoe hare populations and predicted that a minimum of 0.4 to 0.7 hares per acre (1.1 to 1.8 hares per hectare) was required for persistence of a reintroduced lynx population in the southern portion of the lynx range.

The boreal forest landscape must contain a mosaic of forest stand successional stages to sustain lynx populations over the long term as the condition of individual stands changes over time. If the vegetation potential (or climax forest type) of a particular forest stand is conducive to supporting abundant snowshoe hares, it likely will also go through successional phases that are unsuitable as lynx foraging or denning habitat (Agee 2000, pp. 6272; Buskirk et al. 2000b, pp. 403 408). For example, a boreal forest stand where there has been recent disturbance, such as fire or timber harvest, that has resulted in little or no understory structure is unsuitable as snowhoe hare habitat for lynx foraging. That stand may regenerate into suitable snowshoe hare (lynx foraging) habitat within 10 to 25 years, depending on local conditions (Ruediger et al. 2000, pp. 13, 14, 2225). However, forest management techniques that thin the understory may render the habitat unsuitable for hares and, thus, for lynx (Ruediger et al. 2000, pp. 2432; Hoving et al. 2004, pp. 291292). Stands may continue to provide suitable snowshoe hare habitat for many years until woody stems in the understory become too sparse as a result of undisturbed forest succession or management (e.g., clearcutting or thinning). Thus, if the vegetation potential of the stand is appropriate, a stand that is not currently in a condition that is suitable to support abundant snowshoe hares for lynx foraging or coarse woody debris for den sites has the capability to develop into suitable habitat for lynx and snowshoe hares with time.

As described previously, snowshoe hares prefer boreal forest stands that have a dense horizontal understory to provide food, cover, and security from predators. Snowshoe hares feed on conifers, deciduous trees, and shrubs (Hodges 2000b, pp. 181183). Snowshoe hare density is correlated to understory cover between approximately 3 to 10 ft (1 to 3 m) above the ground or snow level (Hodges 2000b, p. 184, Table 7.5). Habitats most heavily used by snowshoe hares are stands with shrubs, stands that are densely stocked, and stands at ages where branches have more lateral cover (Hodges 2000b, p. 184). In Maine, the snowshoe hare densities were highest in the stands supporting high conifer stem densities (Homyack et al. 2004, p. 195; Robinson 2006, p. 69). In northcentral Washington, snowshoe hare density was highest in 20year old lodgepole pine stands where the average density of trees and shrubs was 6,415 stems per acre (ac) (15,840 stems/hectare (ha)) (Koehler 1990, p. 848). Generally, earlier successional forest stages support a greater density of horizontal understory and more abundant snowshoe hares (Buehler and Keith 1982, p. 24; Wolfe et al. 1982, pp. 668669; Koehler 1990, pp. 847848; Hodges 2000b, pp. 184191; Griffin 2004, pp. 8488); however, sometimes mature stands also can have adequate dense understory to support abundant snowshoe hares (Griffin 2004, p. 88). In Montana, lynx favor multistory stands, often in older age classes, where tree boughs touch the snow surface but where stem density is low (Squires 2006, p. 4).

In Maine, the highest snowshoe hare densities were found in regenerating softwood (spruce and fir) and mixed wood stands (Fuller and Harrison 2005, pp. 716, 719; Robinson 2006, p. 69). In the North Cascades, the highest snowshoe hare densities were found in 20yearold seral lodgepole pine stands with a dense understory (Koehler 1990, pp. 847848). In montane and subalpine forests in northwest Montana, the highest snowshoe hare densities in summer were generally in younger stands with dense forest structure; in winter snowshoe hare densities were as high or higher in mature stands with dense understory forest structure (Griffin 2004, p. 53). Snowshoe hare studies are just underway in Minnesota (Moen et al. 2005, p. 18); therefore, results on habitat relationships are still preliminary. In the GYA, the highest snowshoe hare densities were found in a douglas fir site and a few regenerating lodgepole pine and lodgepole stands that had a lodgepole understory. Low hare densities were found in most regenerating lodgepole stands, most likely due to low stem densities (Hodges and Mills 2005, p. 6). Sprucefir forests were the stand type most likely to support snowshoe hares; however, hare densities were never high at these sites.

Habitats supporting abundant snowshoe hares must be present in a large proportion of the landscape to support a viable lynx population. Broadscale snowshoe hare density estimates are not available for the areas we are proposing as lynx revised critical habitat; available snowshoe hare density estimates are only applicable for the immediate area and time frame for which the study was conducted and cannot be extrapolated further.

b. Snow Conditions (Other Physiological Requirements)

As described in the ``Background'' section above, snow conditions also determine the distribution of lynx. Deep, fluffy snow conditions likely restrict potential competitors such as bobcat or coyote from effectively encroaching on or hunting in winter lynx habitat. Snowfall was the strongest predictor of lynx occurrence at a regional scale (Hoving et al. 2005, p. 746, Table 5). In addition to snow depth, other snow properties, including surface hardness or sinking depth, are important factors in the spatial, ecological, and genetic structuring of the species (Stenseth et al. 2004, p. 75).

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In the northeastern United States, lynx are most likely to occur in areas with a 10year mean annual snowfall greater than 105 in (268 cm) (Hoving 2001, p. 75). The Northern Superior Uplands section of Minnesota, which roughly corresponds to the area proposed as revised critical habitat in that State, receives more of its precipitation as snow than any section in the State, has the longest period of snow cover, and has the shortest growing season (Minnesota DNR 2003, p. 2). Mean annual snowfall from 1971 to 2000 in this area was generally greater than 55 in (149 cm) (University of Minnesota 2005).

Information on average snowfall or snow depths in mountainous areas such as the Cascades or northwest Montana is limited because few weather stations in these regions have measured snow fall or snow depth over time. Topography strongly influences local snow conditions. In the Cascades, at the Mazama station, average annual snowfall from 1948 to 1976 was 115 in (292 cm) (Western Regional Climate Center 2005). In Montana, at the Seeley Lake Ranger Station, average annual snowfall from 1948 to 2005 is 124 in (315 cm), while at the Troy station the average total snowfall from 1961 to 1994 was 90 in (229 cm) (Western Regional Climate Center 2005).

We considered the effect climate change could have on average snowfall or snow depths when we developed this proposed rule. We have information to indicate that up to twothirds of the lynx range in the lower 48 States may become unsuitable by 2100 (Gonzalez et al. 2007, pp. 4, 78, 10, 1314, 19). However, we have used current climate information in developing this rule because, until regional climate projections are more certain, we find it is appropriate to designate critical habitat for lynx where they currently exist. Projections for habitat loss go out over the next 100 years. If designated habitat becomes unsuitable for lynx in the future due to climate change, the Service will revise critical habitat to remove unsuitable habitat and add new suitable habitat in order to seek to facilitate the shift in lynx range that climate change may cause. Lynx distribution and habitat is likely to shift upward in elevation and northward in latitude as temperatures increase (Gonzalez et al. 2007, pp. 7, 1314, 19). All proposed revised critical habitat units include the highestelevation habitats that lynx would be able to use in the event that they move to higher elevations in response to climate change. Additionally, any northward shifts in range would likely move the species and its suitable habitat into Canada. Four of the five proposed revised critical habitat units use the United States/Canada border as their northern boundary.
Sites for Breeding, Reproduction, or Rearing (or Development) of OffspringDenning Habitat

Lynx den sites are found in mature and younger boreal forest stands that have a large amount of cover and downed, large woody debris. The structural components of lynx den sites are common features in managed (logged) and unmanaged (e.g., insect damaged, windthrow) stands. Downed trees provide excellent cover for den sites and kittens and often are associated with dense woody stem growth.

Site characteristics were evaluated for 26 lynx dens from 1999 to 2004 in northwest Maine. Dens were found in several stand types. Tipup mounds (exposed roots from fallen trees) alone best explained den site selection (J. Organ, Service, unpubl. data). Tipup mounds may purely be an index of downed trees, which were abundant on the landscape. Horizontal cover at 16 ft (5 m) alone was the next best predictor of denning (J. Organ, unpubl. data). Dead, downed trees were sampled, but did not explain den site selection as well as tipup mounds and cover at 16 ft (5 m). Lynx essentially select dense cover in a coverrich area.

In the North Cascades, Washington, lynx denned in mature (older than 250 years) stands with an overstory of Engelman spruce, subalpine fir, and lodgepole pine with an abundance of downed, woody debris (Koehler 1990, p. 847). In this study, all den sites were located on northnortheast aspects (Koehler 1990, p. 847). In northwest Montana, areas around dens were a variety of ages but all contained abundant woody debris including downed logs, blowdowns, and rootwads, and dense understory cover (Squires et al. 2004b, Table 3). Information on den site characteristics in Minnesota has not yet been reported (Moen et al. 2005, p. 8).

Primary Constituent Element for Lynx

Within the geographical area we know to be occupied by the lynx, we must identify the primary constituent elements (PCEs) laid out in the quantity and spatial arrangement essential to the conservation of the species (i.e., essential physical and biological features) that may require special management considerations or protections.

Based on the above needs and our current knowledge of the life history, biology, and ecology of the species, we have determined that the primary constituent element essential to the conservation of the lynx is:
(1) Boreal forest landscapes supporting a mosaic of differing successional forest stages and containing:
(a) Presence of snowshoe hares and their preferred habitat conditions, including dense understories of young trees or shrubs tall enough to protrude above the snow;
(b) Winter snow conditions that are generally deep and fluffy for extended periods of time;
(c) Sites for denning having abundant, coarse, woody debris, such as downed trees and root wads; and
(d) Matrix habitat (e.g., hardwood forest, dry forest, nonforest, or other habitat types that do not support snowshoe hares) that occurs between patches of boreal forest in close juxtaposition (at the scale of a lynx home range) such that lynx are likely to travel through such habitat while accessing patches of boreal forest within a home range. The important aspect of matrix habitat for lynx is that these habitats retain the ability to allow unimpeded movement of lynx through them as lynx travel between patches of boreal forest.

We designed the proposed revised critical habitat units to capture these elements of the PCE laid out in the quantity and spatial arrangement essential to the conservation of the species (i.e., essential physical and biological features). To do this, we mapped units across the geographic range of the species in the United States to protect populations in the event of catastrophic events that could impact a portion of the range. We designed each unit to be large enough to encompass the temporal and spatial changes in habitat and snowshoe hare populations to support interbreeding lynx populations or metapopulations over time.

Special Management Considerations or Protections

When designating critical habitat, we assess whether the occupied areas contain the physical and biological features that are essential to the conservation of the species and that may require special management considerations or protections.

The area proposed for designation as revised critical habitat will require some level of management to address the current and future threats to the lynx and to maintain the physical and
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biological features essential to the conservation of the species. In all units, special management will be required to ensure that boreal forest landscapes provide a mosaic of forest stands of various ages to provide abundant prey habitat, denning habitat, and connectivity within the landscape. The designation of critical habitat does not imply that lands outside of critical habitat do not play an important role in the conservation of the lynx. Federal activities that may affect areas outside of critical habitat, such as forest management, development, and road construction, are still subject to review under section 7 of the Act if they may affect lynx because Federal agencies must consider both effects to lynx and effects to critical habitat independently. The prohibitions of section 9 of the Act (e.g., harm, harass, capture, kill) also continue to apply both inside and outside of designated critical habitat.

Special management direction for lynx has been applied to public lands in much of the lynx DPS. The USFS, Bureau of Land Management (BLM), NPS, and the Service developed a Lynx Conservation Assessment and Strategy (LCAS) (Ruediger et al. 2000, entire) using the best available science at the time specifically to provide a consistent and effective approach to conserve lynx and lynx habitat on Federal lands (Ruediger et al. 2000). The overall goals of the LCAS were to recommend lynx conservation measures, to provide a basis for reviewing the adequacy of USFS and BLM land and resource management plans with regard to lynx conservation, and to facilitate conferencing and consultation under section 7 of the Act. The LCAS identifies an inclusive list of 17 potential risk factors for lynx or lynx habitat that may be addressed under programs, practices, and activities within the authority and jurisdiction of Federal land management agencies. The risks identified in the LCAS are based on effects to either individual lynx, lynx populations, or both, or to lynx habitat. Potential risk factors the LCAS addresses that may affect lynx productivity include: timber management, wildland fire management, recreation, forest/backcountry roads and trails, livestock grazing, and other human developments. Potential risk factors the LCAS addresses that may affect lynx mortality include: trapping, predator control, incidental or illegal shooting, and competition and predation as influenced by human activities and highways. Potential risk factors the LCAS addresses that may affect lynx movement include: highways, railroads and utility corridors, land ownership pattern, and ski areas and large resorts. Other potential largescale risk factors for lynx addressed by the LCAS include: fragmentation and degradation of lynx refugia, lynx movement and dispersal across shrubsteppe habitats, and habitat degradation by nonnative and invasive plant species.

The LCAS used the best available information at the time to ensure the appropriate mosaic of habitat is provided for lynx on Federal lands. Although the LCAS was written specifically for Federal lands, many of the conservation measures are pertinent for nonFederal lands. To facilitate project planning and allow for the assessment of the potential effects of a project on an individual lynx, the LCAS directs Federal land management agencies to delineate Lynx Analysis Units (LAUs). The scale of an LAU approximates the size of area used by an individual lynx (25 to 50 mi\2\ (65 to 130 km\2\)). The LCAS recognizes that LAUs will likely encompass both lynx habitat and other areas (e.g., lakes, low elevation ponderosa pine (Pinus ponderosa) forest, and alpine tundra). Habitatrelated standards the LCAS provides to address potential risks include: (1) If more than 30 percent of lynx habitat in an LAU is currently in unsuitable condition, no further reduction of suitable condition shall occur as a result of vegetation management activities by Federal agencies; (2) within an LAU, maintain denning habitat in patches generally larger than 5 ac (2 ha), comprising at least 10 percent of lynx habitat; (3) maintain habitat connectivity within and between LAUs; (4) management actions (e.g., timber sales, salvage sales) shall not change more than 15 percent of lynx habitat within an LAU to an unsuitable condition within a 10year period; (5) precommercial thinning will only be allowed when stands no longer provide snowshoe hare habitat; (6) on Federal lands in lynx habitat, allow no net increase in groomed or designated overthesnow routes and snowmobile play areas by LAU.

With the listing of the lynx in 2000, Federal agencies across the contiguous United States range of the lynx were required to consult with the Service on actions that may affect lynx. The LCAS assists Federal agencies in planning activities and projects in ways that benefit lynx or avoid adverse impacts to lynx or lynx habitat (Ruediger et al. 2000). If projects are designed that fail to meet the standards in the LCAS, the biologists using the LCAS would arrive at an adverse effect determination for lynx.

A Conservation Agreement between the USFS and the Service (U.S. Forest Service and U.S. Fish and Wildlife Service 2000) and a similar Agreement between the BLM and the Service (Bureau of Land Management and U.S. Fish and Wildlife Service 2000) committed the USFS and BLM to use the LCAS in determining the effects of actions on lynx until Forest Plans were amended or revised to adequately conserve lynx. A programmatic biological opinion pursuant to section 7 of the Act analyzed and confirmed the adequacy of the LCAS and its conservation measures to conserve lynx and concluded that Forest Service and BLM land management plans as implemented in accordance with the Conservation Agreements would not jeopardize the continued existence of lynx (U.S. Fish and Wildlife Service 2000).

In 2005, the USFS and the Service renewed the conservation agreement (U.S. Forest Service and U.S. Fish and Wildlife Service 2005) because the original agreement had expired. In the 2005 agreement, the parties agree to take measures to reduce or eliminate adverse effects or risks to lynx and its occupied habitat pending amendments to Forest Plans. The LCAS is a basis for implementing this agreement (U.S. Forest Service and U.S. Fish and Wildlife Service 2005). The 2005 agreement was renewed on October 20, 2006, and expires December 31, 2010, unless renewed. The BLM continues to adhere to their original agreement although it expired in December 2004.

Lynx conservation depends on management that supports boreal forest landscapes of sufficient size to encompass the temporal and spatial changes in habitat and snowshoe hare populations to support interbreeding lynx populations or metapopulations over time. At the time it was written, the LCAS provided the highest level of management or protection for lynx. The LCAS conservation measures address risk factors affecting lynx habitat and lynx productivity and were designed to be implemented at the scale necessary to conserve lynx. This level of management is appropriate for Federal lands, because they account for the majority of highquality habitat in the United States and also because the inadequacy of regulatory mechanisms to conserve lynx on these lands at the time was the primary reason for listing the lynx as a threatened species under the Act. Furthermore, new information has come to light since the LCAS was written concerning that should be taken
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into account by land managers. For instance, Kolbe et al. (2007) and Bunnell et al. (2006) published information on the effects of snowmobiling on lynx, and Squires et al. (2006) documented the importance of multilayered stands as snowshoe hare habitat. Further, ongoing research in Minnesota and Maine has also resulted in information helpful to forming our understanding o

FOR FURTHER INFORMATION CONTACT Mark Wilson, Field Supervisor, Montana Ecological Services Office, 585 Shepard Way, Helena, MT, 59601; telephone 4064495225. If you use a telecommunications device for the deaf (TDD), call the Federal Information Relay Service (FIRS) at 800 8778339.