Seasonal distribution analysis of five lasiurine bat species: clues to migration patterns and behavior

Abstract

Abstract Lasiurus is a bat genus recognised to have migratory species. However, little is known about the seasonal distribution for most of its species. We used spatial analysis of occurrence records and ecological niche modeling to evaluate the seasonal distributions of five species: Lasiurus borealis, Lasiurus frantzii, Lasiurus ega, Lasiurus xanthinus, and Lasiurus intermedius, to disentangle their seasonal distribution patterns. L. intermedius, L. xanthinus, and L. frantzii presented distinct seasonal patterns in the rate of occurrence records in different areas, which accumulate most records in the northern populations in summer. For L. borealis, we found seasonal variation throughout its entire distribution, with most records in summer and a progressive decline towards winter. In contrast, L. ega showed no seasonal changes in any region. In species with seasonal changes in their occurrences records, the projections of summer conditions did not predict their preferred winter conditions, suggesting these species occupy different ecological niches seasonally. We found seasonality in the northern areas of these species’ distributions, although we could not distinguish whether migration movements or torpor behaviors are the underlying cause. Conversely, we suggest that most central and southern populations of the five species do not exhibit seasonality and are year-round residents.