DOI: 10.5061/dryad.xpnvx0kq2
title: Data from: Insectivorous birds and bats outperform ants in the top-down regulation of arthropods across strata of a Japanese temperate forest

description: Birds, bats, and ants are recognized as significant arthropod predators.
 However, empirical studies reveal inconsistent trends in their relative
 roles in top-down control across strata. Here, we describe the differences
 between forest strata in the separate effects of birds, bats, and ants on
 arthropod densities and their cascading effects on plant damage. We
 implemented a factorial design to exclude vertebrates and ants in both the
 canopy and understory. Additionally, we separately excluded birds and bats
 from the understory using diurnal and nocturnal exclosures. At the end of
 the experiments, we collected all arthropods and assessed herbivory
 damage. Arthropods responded similarly to predator exclusion across forest
 strata, with a density increase of 81% on trees without vertebrates and
 53% without both vertebrates and ants. Additionally, bird exclusion alone
 led to an 89% increase in arthropod density, while bat exclusion resulted
 in a 63% increase. Herbivory increased by 42% when vertebrates were
 excluded and by 35% when both vertebrates and ants were excluded. Bird
 exclusion alone increased herbivory damage by 28%, while the exclusion of
 bats showed a detectable but non-significant increase (by 22%). In
 contrast, ant exclusion had no significant effect on arthropod density or
 herbivory damage across strata. Our results reveal that the effects of
 birds and bats on arthropod density and herbivory damage are similar
 between the forest canopy and understory in this temperate forest. In
 addition, ants were not found to be significant predators in our system.
 Furthermore, birds, bats, and ants appeared to exhibit antagonistic
 relationships in influencing arthropod density. These findings highlight,
 unprecedentedly, the equal importance of birds and bats in maintaining
 ecological balance across different strata of a temperate forest.
description: We collected this dataset in the Tomakomai experimental forest in
 Hokkaido, Japan.  We conducted two parallel experiments
 with different purposes. The Canopy-Understory Vertebrate and Ant
 Exclusion (CUVA) experiment focused on predator effects (ants,
 vertebrates, and their combination) on arthropod densities and herbivory
 in the forest understory and canopy, while the Understory Bird and Bat
 Exclusion (UBB) experiment specifically examined the individual effects of
 birds and bats in the understory. Additionally, we complemented our
 research on the impact of predators on arthropods and plants by conducting
 surveys of the excluded predator communities. Each experiment was
 conducted twice: first in 2018 and then replicated in 2019. 
description: # Insectivorous birds and bats outperform ants in the top-down regulation
 of arthropods across strata of a Japanese temperate forest
 [https://doi.org/10.5061/dryad.xpnvx0kq2](https://doi.org/10.5061/dryad.xpnvx0kq2) Here are the two main important datasets used throughout the manuscript. Arthropod_dataset.xlsx shows the total arthropod density per sample found in our study as well as the densities partionned into four feeding guilds: NR, Sapsuckers, Herbivores and Predators. Herbivory_datatset.xlsx presents the herbivory estimations found for each twig in our study. ## Description of Arthropod\_dataset.xlsx PlantSpeciesAnal : Tree species  Strata : Stratum where the arthropods were collected to measure herbivory (Understory or Canopy) Patrol : Season of Collection (A or B) Treatment : Name of each treatment (ALL, ANT, CN2, CN3, BIR, BAT, CN1) Total.arth : Total number of collected arthropods  Herb : Number of collected herbivorous arthropods NR : Number of collected NR arthropods (Arthropods with No Relationships with herbivory or other predators)  Pred : Number of collected Predatory arthropods Sap : Number of collected sapsucking arthropods TotalLeafArea : Mean area of the leaves (cm²) Tot.ab.f : Total density of arthropods (abundance of arthropods / mean leaf area) Tot.ab.herb : Density of herbivorous arthropods Tot.ab.NR : Density of NR arthropods Tot.ab.Pred : Density of predatory arthropods Tot.ab.sap : Density of sapsucking arthropods ## Description of Herbivory\_dataset.xlsx Strata : Stratum where the leaves were collected to measure herbivory (Understory or Canopy) Treatment: Name of each treatment (ALL, ANT, CN2, CN3, BIR, BAT, CN1) Experiment : Name of the experiment (CUVA, UBB or CN3) Patrol : Season of Collection (A or B) HerbProp : Herbivory estimation (proportions) Twig : Color of the twig of the selected branch SpeciesAnal : Tree species