DOI: 10.5061/dryad.ghx3ffbtk
title: Raw data: Temperature and water availability drive insect seasonality across a temperate and a tropical region

description: The more insects there are, the more food there is for insectivores and
 the higher the likelihood of insect-associated ecosystem services. Yet, we
 lack insights into the drivers of insect biomass over space and seasons,
 both for tropical and temperate zones. We used 245 Malaise traps, managed
 by 191 volunteers and park guards, to characterise year-round flying
 insect biomass in a temperate (Sweden) and a tropical (Madagascar)
 country. Surprisingly, we found that local insect biomass was similar
 across zones. In Sweden, local insect biomass increased with accumulated
 heat and varied across habitats, while biomass in Madagascar was unrelated
 to the environmental predictors measured. Drivers behind seasonality
 partly converged: In both countries, the seasonality of insect biomass
 differed between warmer and colder sites and wetter and drier sites. In
 Sweden, short-term deviations from expected season-specific biomass were
 explained by week-to-week fluctuations in accumulated heat, rainfall, and
 soil moisture, whereas in Madagascar, weeks with higher soil moisture had
 higher insect biomass. Overall, our study identifies key drivers of the
 seasonal distribution of flying insect biomass in a temperate and tropical
 climate. This knowledge is key to understanding the spatial and seasonal
 availability of insects — as well as predicting future scenarios of insect
 biomass change.
description: To describe the large-scale distribution of flying insect
 biomass, we sampled insects during one year in a temperate (Sweden;
 latitude 55.3 to 69.1) and a tropical (Madagascar; latitude -25.6 to
 -12.0) country, across the full latitudinal and longitudinal gradient of
 each country. Sweden and Madagascar are comparable in their surface area,
 covering ~450,000 and ~590,000 km<sup>2</sup> respectively.
 The climate in Sweden ranges from oceanic to sub-Arctic, and in Madagascar
 from tropical humid to dry tropical. Insects were
 collected with Malaise traps, and preserved in 95% ethanol. In Sweden, 195
 Malaise traps were set out between January and December 2019. Samples from
 Malaise traps were collected monthly or bi-weekly during winter and autumn
 (approx. October to February, depending on latitude) and weekly during
 spring and summer (approx. March to September, depending on latitude). In
 Madagascar, 50 Malaise traps were set out from August 2019 to July 2020.
 Samples from Malaise traps were collected every week during the entire
 year, and about 75% of the catch was processed further. The collection
 dates of the selected samples for each trap were evenly distributed across
 the year. Hence, the selected samples provided us with weekly to biweekly
 data on insect biomass in Madagascar.  Insect biomass
 from each sample was obtained following the protocol described in
 Iwaszkiewicz-Eggebrecht et al. (in revision). All samples were drained to
 remove excess ethanol. The insect biomass in the sample was then weighed
 to the nearest 0.001 gram, and the average bottle weight was subtracted
 from this value.
description: # Raw data: Temperature and water availability drive insect seasonality
 across a temperate and a tropical region --- Datasets include information
 on samples of insect biomass, collected in Sweden and Madagascar. Datasets
 also include climatic predictors used in the analyses, both for Sweden and
 Madagascar. ## Description of the Data and file structure More information
 on the data files and structure can be found in the
 "README.xlsx". The tab "Description of the data files"
 contains general information on each dataset. The tab "metadata"
 contains information on each column in the datasets. ## Sharing/Access
 Information *Climate variables were generated based on data downloaded
 from the ERA5-Land database.* Muñoz Sabater, J. (2019): ERA5-Land hourly
 data from 1950 to present. Copernicus Climate Change Service (C3S) Climate
 Data Store (CDS).  DOI: 10.24381/cds.e2161bac
 [https://cds.climate.copernicus.eu/cdsapp#!/dataset/reanalysis-era5-land?tab=overview](https://cds.climate.copernicus.eu/cdsapp#!/dataset/reanalysis-era5-land?tab=overview)