2.1 Study area
We deployed paired temperature loggers (one within and one outside each pond) in 16 intermittent ponds in the Coronado National Forest, located within the Huachuca Mountains Canelo Hills (HMCH) region and San Rafael Valley of southeastern Arizona, USA in June and July 2018 (Figure 1). The HMCH region is part of the Madrean Sky Islands, with an elevation range of approximately 1150 m to 2880 m. Habitat composition includes cienega wetlands, semi-arid grasslands and thorn-scrub, and evergreen and coniferous woodlands. The climate of this region is semi-arid, with up to half of the annual rainfall occurring during the summer monsoon season (Sheppard et al., 2002). Rain events during the monsoon season are typically short in duration, high in intensity, and seasonally predictable but spatially variable (Goodrich et al., 2008). Ponds in the region were originally constructed to provide water for livestock and are often called “stock tanks”; these ponds are now surrogating for aquatic habitat lost to human activities and support a range of aquatic species (Rosen & Schwalbe 1998; Storfer et al. 2014; Mims et al. 2016). We selected ponds based on historical hydroperiod data that indicated they were generally intermittent and tended to have longer (>1 month) duration wetted phases (Parsley et al., 2020).