A new generation of eBird Trends maps, released in November 2022, provides an unprecedented fine-scale view of where bird species are increasing or decreasing. Identifying such trends is the crucial first step to begin identifying ways to reverse pervasive declines like the ones identified by the 2022 U.S. State of the Birds report and the State of the World’s Birds.
What are eBird Trends maps?
eBird Trends maps show where bird abundance has increased (blue), decreased (red), or where change has been uncertain (white) from 2007-2021 within a 27 x 27 km region (represented by a circle). The darker the color, the stronger the trend. The trend shows an estimate of the cumulative percent change in population size from 2007 to 2021 and does not represent annual fluctuations in populations.
Every 27 x 27 km region on the map is also scaled by an estimate of abundance based on abundance data from 2014. Circles that are larger show where more individuals of a given species occur. Hence, larger and darker red circles indicate that a larger proportion of the population is declining.
How eBird Trends Maps Can Help Land Trusts
For the first time you’ll be able to see exactly where bird populations are increasing or decreasing within an 8-mile radius, an area smaller than many counties. Building knowledge about trends at a local level will also help us answer questions about climate change using birds as environmental indicators. Identifying pockets of land within your service area where birds are increasing or decreasing can help your organization invest limited conservation dollars in areas with the greatest stewardship potential and enables land trusts to target land management and protection efforts around species of particular interest. Land trusts may consider using eBird trends maps in outreach materials and grant applications to demonstrate the need for avian habitat management.