Immediate birdsong changes following cool-burn fires in Kruger National Park

Fire is an important driver of ecosystems, especially savannas. The effects of fire on bird community structure and biodiversity have been studied in various ecosystems with diverse results, especially when studied in savannas. The savanna of Kruger National Park (KNP) in South Africa has been heavily managed under a heterogenous fire regime for over 50 years, and extensive data have been collected from experimental burn plots (EBPs) that undergo different fire regimes. However, little study has been given to the effects of fire on birds in KNP. Birds are known to change their song structure and behaviour in response to environmental changes, but this has not been studied regarding fire. This paper characterises the effects that burning has on vocalisations of two study species in KNP: Ring-necked (Cape Turtle) Doves and Fork-tailed Drongos. Significant overall effects of fire treatment on vocalisation were found for both species. The changes observed in Ring-necked Doves suggest that the birds were undergoing heightened stress, whereas those seen in Fork-tailed Drongos suggest acoustic adaptation. These effects of fire on song structure are novel findings that can serve as a basis for future research in fire ecology and bioacoustics.