Data coverage, biases, and trends in a global citizen-science resource for monitoring avian diversity

Aim: Understanding and addressing the global biodiversity crisis requires ecological information compiled continuously from across the globe. Data from citizen science initiatives are useful for quantifying species’ ecological niches and geographical distributions but can be difficult to apply towards biodiversity monitoring. The presence of fixed geographical locations reduces the opportunistic nature of citizen science data, allowing for more reliable and nuanced trend estimation. The eBird citizen-science programs contains predefined locations whose bird assemblages are sampled across years (‘hotspots’). For hotspots to function as a biodiversity monitoring resource, issues related to data coverage, biases, and trends need to be addressed.
Location: Global.
Methods: We estimated the survey completeness of species richness at 300,500 eBird hotspots during the years 2002 to 2022. We documented sampling biases at eBird hotspot and non-hotspot locations during 2022 based on protection st..., , , # Data coverage, biases, and trends in a global citizen-science resource for monitoring avian diversity

One CSV file containing the results from the survey completeness analysis of 300,500 eBird hotspots conducted during four seasons from 2002 to 2022.

## Description of the data and file structure

eBird-hotspot-table.csv
The 300,500 eBird hotspots are considered in the analysis with their unique ID (loc_id) and their longitude and latitude. From these, the 76,200 eBird hotspots with sufficient data to estimate survey completeness for at least one season and year with observed species richness, estimated species richness, and estimated survey completeness (SC).

## Sharing/Access information

The bird occurrence data are available from [https://science.ebird.org/en/use-ebird-data](https://science.ebird.org/en/use-ebird-data)