DOI: 10.5061/dryad.bk3j9kd7d
title: The construction of small-scale, quasi-mechanistic spatial models of insect energetics in habitat restoration: a case study of beetles in Western Australia

description: Aim: The management and restoration of ecological processes mediated by
 biotic interactions is now broadly advocated, and may be achieved by the
 targeting restoration towards key agents. Although theoretically examined,
 a practical approach to incorporating the physiology and energetics of
 insects into restoration planning is poorly articulated. I aimed to
 provide a case study using the thermal biology and energetics of beetles
 to identify the distribution of habitat suitability in a large restoration
 landscape. Location: South-west Western Australia. Methods: I modelled the
 thermal performance of metabolic rates of thirteen Phyllococerus
 purpurascens, and twenty Colpochila ‘species 2’, measured repeatedly at
 seven temperatures between five and 40 °C using flow-through respirometry.
 Thermal constraints were used to inform a species distribution model of
 each species at extremely high spatiotemporal resolution, projecting the
 physiological state of each species for every hour at 5” resolution across
 a 152km2 restoration landscape in south-western Australia to estimate the
 habitat suitability for beetles. Results: Both species’ metabolic rates
 increased exponentially to a critical point, followed by rapid decline,
 but the thermal tolerance thresholds were different for each species. Both
 had strikingly high thermal tolerance relative to their nocturnal habits,
 and local climatic conditions. The models of beetle prevalence estimated
 both species to be active and able to access the entire project area for
 all of the austral spring, summer and autumn. Main Conclusions: The
 results reported here suggest ubiquitous habitat suitability for flower
 beetles in a disturbed landscapes. Incorporation of similar mechanistic
 models for other species at high resolution offers potential insight into
 habitat suitability for a broad range of ectotherms.
description: <i>Study
 Location,</i><i> Animal Source and
 Maintenanc</i>e The Gnangara Mound defines a
 large, elevated area of sand north Perth, Western Australia, subtended by
 an aquifer which is currently the single most important source of potable
 water for the city.  Although the native vegetation is predominantly
 <i>Banksia</i> woodlands, which are a nationally protected
 community, the area was extensively clear-felled in the late 1920’s for
 the establishment of commercial pine plantations, the removal and
 restoration of which are planned by 2028. Much of the rest of the region
 is semi-rural, with sub-urban residential estates developed in the early
 1990s. The projection area described by this data set represents
 approximately 152 square kilometers of this region, encompassing the
 majority of pine plantations in the area, extending from the southern
 border of Yanchep National Park in the north, to the northern border of a
 private conservation reserve, Whiteman Park, in the south. <i>Thermo-energetic Landscape Context</i> While the study region has perviously been the subject of microcliamtic modelling, in this study I used the <i>micro­_global </i>algorithm in the ‘NicheMapR’ package  to achieve this, and tested the accuracy of the model using the data collected by the temperature loggers in the earlier study. The <i>micro_global </i>algorithim employs quasi-mechanistic statistical downscaling of a global climate model on the basis of local geomorphology, soil properties and vegetation to estimate air temperature, relative humidity and wind speed, solar radiation, precipitation, and soil temperature and moisture content. To maintain precision of the microclimatic models at extremely high resolution, these data were extracted at approximately 1 arc-second resolution from published resources, described more fully in the published manuscript. The resulting microclimate model estimated conditions above and below the soil surface for every hour of every day over a ten-year projection period.   The microclimatic model produced was used as the basis for the <i>ectotherm </i>algorithm to project species distributions and habitat suitability for each species, again in the ‘NicheMapR’ package. The <i>ectotherm </i>algorithm is essentially a biophysical model that solves thermal mass-balance equations to estimate heat, water and energy budgets on the basis of specified morphology (body shape), physiology (thermal tolerance thresholds) and behaviour (diurnality or nocturnality), and can be extended to the calculation of dynamic energy budgets across the whole life cycle. The essential tolerance thresholds for the focal beetle species were estimated from the thermal performance experiments decribed in the published manuscript. I used the resulting models to estimate hourly body temperatures (T<sub>b</sub>), metabolic rates (cal.h<sup>-1</sup>), and the activity of each beetle (0 = inactive, 1 = basking and 2 = active). Habitat suitability for the beetles to actively forage was estimated by dividing the average activity by two to estimate the amount of time spent actively foraging. The resulting data were averaged to two estimates (one during daylight hours, the other at night) of T<sub>b</sub>, metabolic rate and activity for each species at each 25m<sup>2</sup> grid square for each solar day, which are summarised here as averages for the austral summer (between solar days 335 and 60), autumn (between solar days 60 and 151), winter (between solar days 152 and243), and spring (between solar days 244 and 334).
description: The data presented here are formatted as an R data set. These
 will open in R as a set of four data frames, which can subsequently be
 further summarised or exported in any format using the standard R
 programming language.