Drivers and spatial patterns of avian defaunation in tropical forests

Aim: Wildlife overexploitation, either for food consumption or for the pet trade, is one of the main threats to bird species in tropical forests. Yet, the spatial distribution and intensity of harvesting pressure on tropical birds remain challenging to quantify. Here, we identify the drivers of hunting-induced declines in bird abundance and quantify the magnitude and the spatial extent of avian defaunation at a pantropical scale.
 

Location: Pantropical
 

Methods: We compiled 2968 abundance estimates in hunted and non-hunted sites across the tropics spanning 518 bird species. Using a Bayesian modelling framework, we fitted species’ abundance response ratios to a set of drivers of hunting pressure and species traits. Subsequently, we applied our model to quantify the spatial patterns of avian defaunation across tropical forests and to assess avian defaunation across biogeographic realms, and for species captured for the pet trade or for food consumption.
 

Re..., We expanded the dataset of hunting impacts on bird populations from Benítez-López et al. (2017) by supplementing additional bird abundance data from local hunting studies through a systematic search of the literature (see details in Supplementary Methods 1). Our final dataset comprises 2968 abundance estimates for 518 tropical bird species at both hunted and non-hunted sites (control) based on 60 local hunting studies (Figure S1, Table SX). Studies that report potential confounding effects, such as habitat loss and logging were not included in our analysis. Changes in abundance due to hunting pressure were subsequently expressed as the response ratio (RR) between the abundance of each bird species (s) in hunted (Xsh) and non-hunted (Xsc) sites within each study (RR =Xsh/Xsc) (Peres & Palacios, 2007; Benítez-López et al., 2017, 2019) RR = 0 then indicates local extinction; 0 < RR < 1, reduction in abundance; RR ≈  1, no changes in abundance and RR > 1, increase in abund..., , # Data from: Drivers and spatial patterns of avian defaunation in tropical forests

This repository is organized into three folders: **Data**, **Scripts**, and **Raster**, which contain the CSV files and R scripts created and used throughout this study.

The **Data** folder contains a CSV file that details changes in bird abundance used to model the impact of hunting. Please note that latitude and longitude have been rounded to one decimal place to protect sensitive data regarding the locations of species subjected to trade and hunting.

| Variables | Type | Description |
| :---------------- | :---------- | :--------------------------------------------------------------------------------------------------------------------- |
| Study | Categorical | Numerical study ID where abundance values in hunted and no-hunted forests were extracted ...,