Effects of fire severity on bird assemblages of mature piedmont forests of Northwestern Argentina

ADRIANA MARISEL MORALES; NATALIA POLITI; LUIS OSVALDO RIVERA; CONSTANZA GUADALUPE VIVANCO; GUILLERMO EMILIO DEFOSSÉ

FOREST ECOLOGY AND MANAGEMENT

ELSEVIER SCIENCE BV

Lugar: Amsterdam; Año: 2023

0378-1127

Fire is an integral part of the ecology of Seasonal Dry Forests. However, fire severity could be a determining factor in the resilience of these forests. The Piedmont Forest is part of the Neotropical Seasonal Dry Forests and concentrates high species biodiversity and endemisms. The Piedmont Forest is one of the most threatened ecosystem of the Andean region, and in recent decades there has been an increasing recurrency of fires of high severity. Our objective was to assess the effects of fire severity on birds that require mature forests of the Piedmont Forest of northwestern Argentina. To achieve this, we selected a mature unburnt site and two sites disturbed by fires of low and high severity. From 2015 to 2017, during the wet (spring-summer) and dry seasons (autumn-winter), we carried out 30 bird points count at each site and recorded birds at four distance categories: 0-10, 10-25, 25-50, 50-100m. To determine bird density, we carried out distance models (Distance Sampling). We analyzed bird richness with the rarefaction method and evaluated the beta diversity through the Sorensen dissimilarity and its components (nestedness and turnover). The birds that require mature forest responses to fires with different severity were evident in the wet season. Our results showed a lower density of birds that require mature forests, closed-nest, cavity-nesting, and residents bird species in high-severity burnt site than low-severity fire burnt site. The high-severity burnt site had a greater loss of the birds that require mature forests, open-nest, cavity-nesting, and residents bird species in their composition than the low- severity burnt site. In contrast, the loss of species of the closed-nest and migratory bird in low-severity burnt site was greater than high-severity burnt site. This study indicates that management should focus on retaining burned patches with different severity fires in undisturbed forest matrix since at the landscape scale will help promote suitable habitats for different bird s that require mature forests in Piedmont Forests of Northwestern Argentina. Also, another management option is prescribed burning since it makes it possible to limit the fire severity without altering the ecological importance for birds. In a context where fires are becoming more severe, is of vital importance the inclusion of information on bird response to fire severity in highly diverse environments, such as the Piedmont Forest of northwestern Argentina, to propose strategies for biodiversity conservation and forest management.