DOI: 10.5061/dryad.2bvq83c0w
title: Data from: Biological traits and biome features mediate responses of terrestrial bird demography to droughts

description: Changing drought regimes are a rising threat to biodiversity, yet their
 impacts on wildlife vary greatly. Acknowledging the factors associated
 with these consequences brings novel insights into species vulnerability
 resulting from extreme climatic events and facilitates effective
 mitigation of climate change risks. Based on 319 observations from 29
 peer-reviewed studies on birds—a well-monitored taxonomic group—we extract
 the responses of demographic metrics to droughts for 204 species across
 eight terrestrial biomes to examine the consequences of droughts. Based on
 relevant studies, we choose the factors potentially moderating bird
 demography under droughts, and complied the data for these factors from
 published datasets. A meta-analysis is performed to determine the drought
 effect on bird demography at individual and population levels, accounting
 for the influence of species traits, timescale and severity of droughts,
 and biome features. The results show that droughts have an overall
 negative effect on bird demography, and the effect is mediated by
 different factors at each level. For individuals exposed to droughts,
 declines in demographic rates are found to be related to narrower extents
 of occurrence of species, and a significant overall reduction in
 demographic rates is identified for individuals residing in deserts and
 xeric shrublands. At the population level, declines in abundance or
 reproductive performance are generally identified for invertivores,
 frugivores, nectarivores, and omnivores; short-lived species with small
 clutch sizes also show greater susceptibilities under the impacts of
 droughts. Our findings additionally suggest that the demographic
 vulnerability of bird individuals and populations could be affected by the
 duration and magnitude of drought episodes. Although our results are
 subject to publication bias, these conclusions advance the assessment of
 vulnerability to extreme climatic events that used to be based on equally
 weighted species traits and support bird conservation by prioritizing the
 declining populations of species with drought-susceptible traits.
description: # Data from: Biological traits and biome features mediate responses of
 terrestrial bird demography to droughts
 [https://doi.org/10.5061/dryad.2bvq83c0w](https://doi.org/10.5061/dryad.2bvq83c0w) ## Description of the data and file structure Appendix 1: The dataset for meta-analyses including the demographic responses of populations of 204 bird species to droughts compiled from 29 publications between 1985 and 2023. Appendix 2: The phylogeny tree of 204 bird species examined for the responses to droughts at individual or population level. The calculation of the phylogenetic distance of species included in the analysis was based on the phylogenetic tree, which was built with the highest overall clade support from a sample of 1,000 phylogenetic trees from the global phylogeny of birds (Jetz et al. 2012) using the maximum-clade-credibility method. ### Files and variables **File: Appendix1_Zhang_et_al._2024.xlsx** **Description:**  ##### Variables: Case_ID: Case identity Study_ID: Study (publication) identity Common_ID: Cases shared the same non-drought level (control) have the same common_ID Author(s): Last names of authors Publish year: The year when the study was published Study period: The period over which the study was conducted Drought period: The period which was reported as “drought” in the study Drought gradient: The gradient of drought severity reported in the study. "Uni" indicates the study has only one drought level; for the studies with multiple drought gradients, the ID of each gradient was listed in this column. Latitude: The latitude of the study site Longitude: The longitude of the study site Species: Species name Order: The taxonomic order of the species Biological level: The biological organization level where the response occurred Response metric: The metric used in the study to measure individual or population responses to droughts ne:Sample size at the drought site nc: Sample size at the non-drought site me: The mean of a response metric at the drought site mc: The mean of a response metric at the non-drought site SDe: Standard deviation of a response metric at the drought site SDc: Standard deviation of a response metric at the non-drought site yi: Effect size of a response metric vi: Standard deviations of a response metric Adult body mass (g): Published values, with missing values extrapolated with a taxonomic hierarchy approach by Bird et al. 2020 Diet type: Fruits and nectar; Invertebrate; Omnivore; Plants and seeds; Vertebrate and scavenging EOO (km2): Extent of occurrence Habitat dependency: Whether the species is a specialist to one habitat type or a non-specialist Maximum longevity (years): Published values, with missing values extrapolated with a taxonomic hierarchy approach by Bird et al. (2020) Mean clutch size: The average number of eggs laid in a single brood by a nesting pair of birds Movement type: Altitudinal Migrant, Full Migrant, Not a Migrant, Nomadic Terrestrial biome: The type of terrestrial biome (Olson et al. 2001) where the response was documented, including TS-BMF: Tropical and subtropical moist broadleaf forests; TS-DBF: Tropical and subtropical dry broadleaf forests; TS-CF: Tropical and subtropical coniferous forests; T-BMF: Temperate broadleaf and mixed forests; T-CF: Temperate coniferous forests; B-TF: Boreal forests/Taiga; TS-GSS: Tropical and subtropical grasslands, savannas, and shrublands; T-GSS: Temperate grasslands, savannas, and shrublands; FL-GS: Flooded grasslands and savannas; MT-GS: Montane grasslands and shrublands; TUN: Tundra; MES-FWS: Mediterranean forests, woodlands, and scrub’; DES-XS: Deserts and Xeric shrublands; MANG: Mangroves; LAK: Lakes; RI: Rock and ice RCL: The latitude of range centroid  dm3: Drought magnitude at 3-month time scale df3: Drought frequency at 3-month time scale dm12: Drought magnitude at 12-month time scale df12: Drought frequency at 12-month time scale Missing values are indicated with "NA"