Fire survival of the Critically Endangered succulent,Euphorbia clivicola R.A. Dyer – fire-avoider or fire-tolerant?

The hypothesized ultimate agent of decline for one of the only two known populations of Euphorbia clivicola R. A. Dyer, a Critically Endangered species endemic to the Northern Province of South Africa, is the unsuitable fire management practised within the Nature Reserve in which the population is protected. Management recommendations concerning the fire regime need to consider fire survival in this succulent species. Fire survival of succulents may be due to the avoidance of fire in refugia or due to fire tolerance by vegetative recovery. Subsequent to a fire, damage to E. clivicola plants was determined. New growth (post-fire resprouting) and rock cover surrounding plants were assessed to determine whether plants tolerated fire through vegetative regrowth or survived fire through protection in refugia. Plants were found to be tolerant of fire, sustaining only mild damage with apparent fire mortality at 3% (2% of the plants were already dead prior to the fire). Fire damage stimulated vegetative regrowth, regrowth being more common in plants that had sustained higher levels of fire damage.