Too dry for lizards: short‐term rainfall influence on lizard microhabitat use in an experimental rainfall manipulation within a piñon‐juniper

Abstract

SummaryEctotherms such as lizards are expected to alter their behaviour and microhabitat use and experience population declines in response to rising temperatures. But the role of changing rainfall patterns on lizard behaviour and microhabitat use is not understood.We used a 5‐year rainfall manipulation experiment in a piñon pine‐juniper woodland in central New Mexico to study how a lizard species' microhabitat use varies in four different rainfall treatments.We examined ground temperatures in the sun and shade, and daily rainfall, within each treatment, during lizard activity periods, to address how lizards used sun or shade microhabitats on a daily basis. Our small‐scale rainfall and temperature measurements indicate that rainfall, not temperatures, predict lizard microhabitat use.Lizards showed a strong preference for shaded microhabitats during dry periods and used sunny microhabitats following rainfall events, regardless of treatment type. Lizards remained active during dry periods, foraging in the shade of trees.Our study shows that rainfall can influence lizard microhabitat use more than temperature in a piñon pine‐juniper woodland and the trees provide important refugia. The loss of piñon pine and juniper trees from prolonged drought threatens to limit the amount of shade available to lizards in the future.