Fire effects on small mammals and vegetation of the Northern Chihuahuan Desert

Abstract

The role of fire in the Northern Chihuahuan Desen has been of great interest and also heavily debated for 40 years. However, few replicated studies have documented the changes brought about by fire. .My study documented the short term effects of fire on a creosotebush (Larrea tridentata) dominated community and associated small mammal community. Prescribed burns were ignited during 13-15 June 1995 on 10 pairs (10 bumed. 10 unbumed) of 25- ha study sites. The 1995 bums reduced shmb (P = '» 006) and grass (P < 0.000) canopy cover to 64 and 16% of the preburn cover, respectively Complete recovery' of the canopy cover had not taken place 1 year post bum Densities of shrubs, primarily creosotebush. tarbush (Flourencia cemua). and cacti species (Opuntia) were reduced 1 year post bum. Mortality of creosotebush (25.6%) was lower than previously reported for summer burns. Tarbush monality (26 3°o) was similar to creosotebush on the study sites. Above average precipitation during June and July 1996 and lower competition by shmbs for available resources promoted an 1160% increase in forb canopy cover on the bumed sites.