Introduction
In order to protect identified wildlife and their habitat, Forest Stewardship Plans have to be created by forest and range licensees under the Forest and Range Practices Act. One of these identified species is the North American badger. It is part of the weasel family and is identified as a species at risk and as endangered according to Identified Wildlife Management Strategy and COSEWIC, respectively. Their favoured habitats include grassland, open forest and modified forested areas. The Wildlife Habitat Decision Aid aims to help forest and range licensees in the creation of their Forest Stewardship Plans.
Description
Badgers have black and white facial markings, are stout and shaggy with short legs, weigh about 6-14 kg and are 65-90 cm long. They have black triangular shaped patches or “badges” on the side of their cheeks also serving as a basis for their name. They also have grey, buff or cream undersides.
Diet
Badgers are specialized to eat burrowing rodents with their strong forearms and long claws. Their prey includes ground squirrels, mice, voles, muskrats, other small mammals, birds, reptiles and fish. Badgers are active throughout the whole year but their prey hibernates. They might kill large numbers of squirrels to get through winter or occupy one of their colonies to eat while their primary prey is hibernating.
Distribution
North American badgers inhabit dry interior grassland and open forest areas in the Thompson, Okanaga, Cariboo and East Kootenay regions in British Columbia. Sometimes they are also found in logged or burned forests in mid- or upper-elevations.
They are mostly found in Ponderosa pine, Bunchgrass, Interior Douglas fir, Montane Spruce, Englemann Spruce-Subalpine, Interior Cedar-Hemlock, Sub-Boreal spruce and Sub-Boreal pine-spruce subzones. They usually inhabit dry climates that can range from hot to cold in temperature.
Habitat
Badgers have large home ranges spanning from 5-20 km2 for females and 50-100 km2 for males and they use them throughout the year. These ranges are usually on open habitat with almost no protection from trees but good soil for digging. Their large home ranges are interrupted by roads resulting in many road related mortalities. Their burrows have an elliptical shape with a width of 20-30 cm and a height of 15-25 cm. They are most commonly found in grassland areas. However, their only habitat needs are prey to eat and soil to dig to make shelter in open grassland. Most of their prey also rely on open areas with little forest cover and good digging soil.
Badgers use digging to catch prey or to make burrows for resting and rearing young. Therefore, they need to live in areas with good digging soil, which include silty, fine sandy and loamy soils. Other less suitable but still habitable soils are clay or sandy soils or cutblock areas with a lot of coarse fragments.
The grassland areas they inhabit are often also near agricultural areas like pastures, golf courses and irrigated fields. In the southern Cariboo region the ground squirrel is absent so the badger populations in that area inhabit more healthy grassland communities which support microtine rodents.
Forest harvesting can create more badger habitat by creating more open areas that will be inhabited by badger prey. In order to make it easier for the badgers to inhabit forested areas they need to be located near other open areas like grassland or open forests.
Current Habitat Protection Measures
Wildlife Habitat Areas (WHAs) can be identified for badgers on Crown Land. These areas aim to protect important habitat features such as prey, soil and burrows, manage livestock grazing activities and forest encroachment and reduce the disturbance of badgers especially during breeding season.
Forest Management Considerations
Harvesting in open forests will increase suitable badger habitat. This might include thinning of conifers of 12.5 cm diameter at breast height and prescribed burning. It is also important to reduce forest encroachment by targeting 20 stems per hectare in late-seral open forests, having 15% or less canopy and maintaining seedlings. The target for mid-seral open forests changes to 75 stems or less per hectare. The seral-stages are used to describe the different successional stages a plant community goes through, ranging from bare ground to the climax. Reducing forest cover and promoting forb production in areas with suitable soil can make an area habitable as long as the open areas are maintained. Forestry can increase the amount of suitable badger habitat greatly, however, if a burrowing site is found in a cutblock Wildlife Tree Patches should be left around it, the accumulation of woody debris on the burrows should be avoided and within a radius of 20 m around the burrow there should be a machine-free zone.
There are several more ways to enhance badger habitat including to plan landscape cutting patterns and improve the connectivity for prey species, close areas with signs of maternal activity between April 1 and August 15 and deactivate roads after the harvesting is over.
Silviculture Considerations
Cutblocks are areas with boundaries, which are open for harvest. If such a cutblock gets regenerated it can decrease the suitability of the badger habitat in that area. Strategies that might help to improve the colonization by prey species include mounding wood debris into piles and prescribed burning. To keep the prey species inside the cutblock it can also be helpful to reduce the density to less than 150 stems per hectare to reduce crown closure. Open areas within or outside of cutblock areas can help squirrels occupy a regenerated area for longer.
Growth and Yield Implications
There may be a reduction in volume productivity due to stocking densities of cutblocks and the free-to-grow standards. Reducing stocking densities might be financially beneficial for licensees. However, the effects of increased ground squirrel population on regenerating forests is unknown and it might be causing damage to seedlings and saplings.
Range Management Considerations
Badger burrows are not very dangerous to livestock. However, fences or excavated burrows by prey are more threatening. In general, grazing activity does not impact badger populations as long as their prey is not depleted and the livestock is not concentrated in areas with abundant badger burrows. Planning grazing patterns can include keeping the grazed sites at a stubble height of 15 cm and other not so heavily grazed sites higher, maintaining native vegetation cover of about 40% or more in mid-august, not letting livestock graze on bunchgrass until late spring, utilizing the rest-rotation grazing strategy and keeping livestock from grazing in already heavily grazed pastures.
Monitoring Recommendations
In order to protect the badger it is important to monitor them properly. In British Columbia if a badger or badger burrow is sighted is it recommended to call the Badger Recovery Team to inform them.
Conclusion
The North American badger is an endangered species that is located in British Columbia. Its conservation is therefore of utmost importance. Their preferred habitats are open forests and grassland or in general habitats with suitable digging soil and prey abundance. Forest harvesting activities can increase badger habitat greatly as it removes forest cover. However, if a burrow is found in a cutblock it should be protected from heavy machinery and by leaving a Wildlife Tree Patch around it. Deactivating roads after the harvesting is complete, closing areas between April 1 and August 15 if there are signs of badger families and planning cutting patterns all enhance connectivity for prey. Silviculture needs to consider that regenerating a cutblock can reduce the probability of badger colonization due to the increase in crown closure. Range licensees should not let their livestock graze on heavily grazed areas and keep these areas at the stubble height of 15 cm. Grazing on bunchgrass should not commence until late spring and using rest-rotation grazing is also very helpful. In order to monitor badger populations more clearly the Badger Recovery Team can be called when there is a sighting of badgers or their burrows.
- Source Weir, R.D. and P.L. Almuedo. 2010. British Columbia’s Southern Interior: Badger Wildlife Habitat Decision Aid. BC Journal of Ecosystems and Management 10(3):9–13.