Multi-Site and Multi-Year Remote Records of Operative Temperatures with Biomimetic Loggers Reveal Spatio-Temporal Variability in Mountain Lizard Activity and Persistence Proxy Estimates

Florèn Hugon,Frank D’Amico,Benoit Liquet

doi:10.3390/rs12182908

Abstract

Commonly, when studies deal with the effects of climate change on biodiversity, mean value is used more than other parameters. However, climate change also leads to greater temperature variability, and many papers have demonstrated its importance in the implementation of biodiversity response strategies. We studied the spatio-temporal variability of activity time and persistence index, calculated from operative temperatures measured at three sites over three years, for a mountain endemic species. Temperatures were recorded with biomimetic loggers, an original remote sensing technology, which has the same advantages as these tools but is suitable for recording biological organisms data. Among the 42 tests conducted, 71% were significant for spatial variability and 28% for temporal variability. The differences in daily activity times and in persistence indices demonstrated the effects of the micro-habitat, habitat, slope, altitude, hydrography, and year. These observations have highlighted the great variability existence in the environmental temperatures experienced by lizard populations. Thus, our study underlines the importance to implement multi-year and multi-site studies to quantify the variability and produce more representative results. These studies can be facilitated by the use of biomimetic loggers, for which a user guide is provided in the last part of this paper.

Highlights

When studies deal with the statistical effects of climate change on biodiversity, the common and oversimplified way of addressing them is to rely on the mean despite climate change leads to greater temperature variability and is associated with higher average climate parameters with greater variability [2]
We found only one study that used biomimetic loggers in mountain and matched the constraint of addressing statistical issues of variability [62]: it illustrates the variation in activity time for lizard species according to altitude but only considered spatial variability, discarding temporal variability being important
We highlighted the effect of the environment spatio-temporal variability on a body temperature proxy, the operative temperature, measured with an original remote sensing tool, a biomimetic logger

Summary

Introduction

Many other studies demonstrate the important role of variability in explaining species responses to climate change [13,14,15] as responses appear to be favored by thermal regimes more than by the mean temperature itself [16,17]. Several studies have shown that there are interactions between mean and variability These two parameters better explain thermal performance when considered together in the model rather than separately as they act in synergy [10]. Climate variability appears to play a major role in species persistence, so it is crucial to integrate it into studies dealing with climate change effects on biodiversity [20,21]

Objectives

Methods

Results

Discussion

Conclusion