Date of this Version
While investigating the American badger (Taxidea taxus) in eastern Colorado’s wheatlands, we studied 3 badgers which were affected by a 2.1 km2 man-made fire and compared them to 2 adjacent badgers unaffected by the fire. All badgers were equipped with radio-telemetry collars and generally located day and night for approximately 1 month pre-fire and 3 weeks post-fire. Three point triangulation locations were converted into a global information system database. Adaptive kernel analyses compared pre- and post-fire horizontal: home ranges (i.e. 95% utilization areas, UAs), core activity areas (50% UAs), movements, den and habitat use patterns. Mean (x) locations pre-fire (43.7) and post-fire (32.0) provided home ranges for affected badgers that averaged 8.3 km2 and 9.2 km2, respectively. While 2 badgers maintained one core area which was outside the burn, the third used 2 core activity areas, one remained the same after the fire and second changed. Diurnal to nocturnal movements (measured in 24 hrs cycles) were pre-fire x = 1.2 km and post-fire x = 1.3 km. Den use remained approximately 5, but some locations changed after the fire. Mean home ranges included 74% winter wheat or wheat stubble. Habitat use for all 5 badgers averaged: 81.4% wheat, 8% riparian, 7.2% sagebrush, and 3.4% burned. Unaffected badgers averaged 7.7 km2 home ranges, 1 core area, 1.0 km diurnal-nocturnal movements, 4 dens, and 93% wheat crops and 7% riparian habitats. After the fire burned 10% of badger 4's home range, 1 of 3 core areas, and 3 of 5 dens, it moved > 3 km northwest into another tributary and established 1 new den. However, it frequently revisited the northern portion of its home range and associated core area. After Approximately 1 month, it consolidated this UA into a new core area 1.7 km northwest and maintained 1 of 3 pre-fire core areas. The fire consumed 6% of Badger 2 home range, and post-fire it moved into the unoccupied southern portion of badger 4’s pre-fire home range. It also moved slowly west into sagebrush probably in partial response to the tilling of approximately 1/3 of its home range which was completed on April 16. Only 1.0% of Badger 1’s home range and its core area were not affected by the fire. However, it slowly moved its home range southeast approximately 1.0 km into the unoccupied area assumed to have been the home range of an un-collared badger found dead in early April. Its core area moved approximately 0.5 km southwest. In summary the movement ecology of affected badgers illustrated three themes: (1) home ranges and core areas moved initially away from the fire, (2) then adjustments were made by each badger in response to other badgers, the burned area, and habitat requirements, and (3) finally a new equilibrium of home ranges was established among these badgers post fire including the use of the burned areas after a few weeks.