FGs

In order to quantify landscape fragmentation, it is first necessary to identify which landscape elements are relevant to the ecological process or organism affected by the fragmentation (Gontier et al., 2006; Girvetz et al., 2008). The specific choice of fragmenting elements defines a so-called "fragmentation geometry". common fragmentation elements that define fragmentation geometries include, but are not limited to: roads, railroads, areas of urban development, industrial zones, and agrivultural fields (Girvetz et al., 2008). Although there is a potential for several fragmentation geometries, we have selected two for our analysis. The limited amount of literature available on the use of the effective mesh size in remote regions similar to the North Yukon has made it difficult, if not impossible, to compare our results with other studies. It is therefore important to use fragmentation geometries that are relevant to this particular study area. Large rivers and other water bodies, and high mountains may also act as barriers to animal movement and can be included in order to detect the combined barrier effect of the relevant natural and anthropogenic landscape elements(Gerlach and Musolf, 2000; Girvetz et al., 2008). Given that the area has a sub-Arctic climate, is one of the most extreme climate regions in Yukon and that continuous permafrost underlies most of the area (NYPC, 2009), potential barriers such as rivers and larger water bodies were not considered in our analysis. Also, since elevation ranges from 325 metres in Old Crow Flats to 1,800 metres in the North Ogilvie Mountains (NYPC, 2009) we have concluded that these mountain ranges were not high enough to be considered as barriers in the landscape. As a result, only the following linear and non-linear feature types present in the footprint data were taken into consideration:

Linear Features

Major Road;
Access Road;
Winter Road;
Community Use Trail;
Trail;
Seismic Line.

Non-Linear Features

Airstrip;
Well Site;
Gravel Pit;
Mine Site;
Settlement;
Traditional Camp;
Tourism / Visitor Facility.

A common distinction between these land use footprints is whether or not they are condidered permanent disturbances. Non-permanent disturbances will likely have a shorter lifespan than permanent features due to the natural re-vegetation of some feature types (NYPC, 2009), as described in the table below. The North Yukon Planning Commission (2007b) estimated that at least 20% of the non-permanent features have been re-vegetated through natural processes, with wildfire playing an important role (NYPC, 2009). Furthermore, the North Yukon Land Use Plan uses the following definition for determining when a land use disturbance, such as a seismic line, may be considered re-vegetated (reclaimed):

"a linear feature or other human-caused surface disturbance that in its current state, does not facilitate increased access or travel. In forested areas, a feature can be considered reclaimed when it contains woody vegetation (trees and / or shrubs) approximately 1.5m in height" (NYPC, 2009).



The first FG includes all land use footprints listed above. By doing so, this FG measures the overall current level of landscape fragmentation in the North Yukon Region.