TY  - JOUR
A1  - Grimm-Seyfarth, Annegret
A1  - Mihoub, Jean-Baptiste
A1  - Henle, Klaus
T1  - Too hot to die? The effects of vegetation shading on past, present, and future activity budgets of two diurnal skinks from arid Australia
JF  - Ecology and evolution
N2  - Behavioral thermoregulation is an important mechanism allowing ectotherms to respond to thermal variations. Its efficiency might become imperative for securing activity budgets under future climate change. For diurnal lizards, thermal microhabitat variability appears to be of high importance, especially in hot deserts where vegetation is highly scattered and sensitive to climatic fluctuations. We investigated the effects of a shading gradient from vegetation on body temperatures and activity timing for two diurnal, terrestrial desert lizards, Ctenotus regius, and Morethia boulengeri, and analyzed their changes under past, present, and future climatic conditions. Both species’ body temperatures and activity timing strongly depended on the shading gradient provided by vegetation heterogeneity. At high temperatures, shaded locations provided cooling temperatures and increased diurnal activity. Conversely, bushes also buffered cold temperature by saving heat. According to future climate change scenarios, cooler microhabitats might become beneficial to warm‐adapted species, such as C. regius, by increasing the duration of daily activity. Contrarily, warmer microhabitats might become unsuitable for less warm‐adapted species such as M. boulengeri for which midsummers might result in a complete restriction of activity irrespective of vegetation. However, total annual activity would still increase provided that individuals would be able to shift their seasonal timing towards spring and autumn. Overall, we highlight the critical importance of thermoregulatory behavior to buffer temperatures and its dependence on vegetation heterogeneity. Whereas studies often neglect ecological processes when anticipating species’ responses to future climate change the strongest impact of a changing climate on terrestrial ectotherms in hot deserts is likely to be the loss of shaded microhabitats rather than the rise in temperature itself. We argue that conservation strategies aiming at addressing future climate changes should focus more on the cascading effects of vegetation rather than on shifts of species distributions predicted solely by climatic envelopes.
KW  - activity predictions
KW  - behavioral thermoregulation
KW  - Ctenotus regius
KW  - extrapolating experimental data
KW  - Morethia boulengeri
KW  - operative temperature
KW  - operative thermal environment
Y1  - 2017
U6  - https://doi.org/10.1002/ece3.3238
SN  - 2045-7758
VL  - 7
SP  - 6803
EP  - 6813
PB  - Wiley
CY  - Hoboken
ER  -