Occupancy and distribution of globally threatened birds in a hotspot susceptible to agricultural expansion.

Abstract

Anthropogenic land-use and land-cover changes have a direct impact on species that depend on native habitats, mainly in biodiversity hotspots undergoing agricultural expansion. In this study, we used occupancy models accounting for imperfect detection to assess the distribution of four threatened species (Celeus obrieni, Herpsilochmus pectoralis, Malacoptila minor, and Xiphocolaptes falcirostris) in an agriculturally relevant region of the Brazilian Cerrado. We analyzed the effect of nine environmental covariates related to climate, topography, land-use, and fire, using 23 years (2000-2022) of sampling data from citizen science and tested different trends of sampling effort on species detection. Our results indicated that forest cover and elevation were the main predictors of occupancy for H. pectoralis, M. minor, and X. falcirostris, whereas C. obrieni responded primarily to climate-related covariates. Detection followed both logistic and exponential patterns, reflecting differences in species ecology and sampling intensity. Spatial predictions revealed a high-priority area in northern Maranhão with overlapping high occupancy probabilities for all four species. We conclude that forest cover, elevation, and climate influence the occupancy of threatened birds in MATOPIBA, highlighting priority areas for conservation in the face of ongoing agricultural expansion and supporting more effective conservation strategies.