Evidence for an Overlooked Western Population of Strix nigrolineata (Black-and-White Owl) in Mexico from Temporal Niche Models and Breeding Records

The Black-and-white Owl (Strix nigrolineata) is a Neotropical raptor whose current distribution extends from southeastern Mexico to South America. Recent citizen science records and field observations have documented the species in west-central Mexico, approximately 550 km northwest of its traditional range limits. We used temporal ecological niche models calibrated with eastern-only occurrence records from 1958–2020 and projected into six decadal climatologies at eastern and western extents to evaluate whether these novel records could represent a recent range expansion or undocumented breeding populations. We complemented the temporal projections with independent field observations that confirmed current occurrence and breeding in western Mexico. Our results show that climatic conditions at the western locations remained within the broader environmental distribution represented by the calibration occurrences, but squared Mahalanobis distances showed a significant ordered increase through time, indicating increasing climatic peripherality. Our study highlights the value of integrating temporal niche models with independent field evidence to uncover cryptic distributions in tropical regions.