Abundance Graphs Overview
The abundance chart shows the months along the bottom and the green bars reflect the frequency of that species in your local area. The taller the green bar, the more likely you are to see one. In the example above, the bar charts give a clear indication of when Nashville Warblers first begin to arrive in spring (2nd week of March), when they reach their peak abundance (April) and when they are gone (late May).
This tool gives you a great idea of what birds to expect in your area, or at any location you choose. The accuracy of this information is dependent on the amount of eBird data in your area. The more good data the better, and another reason for you to participate in this citizen science project by entering your sightings at eBird.org.
More details on how the bar charts work:
The information in the bar chart is an aggregation of eBird data, but it is not the same as the bar charts on the eBird website in a couple of ways. First, the bar charts in BirdsEye cover just the last 5 years, which is intended to provide a better feel for current/recent abundance patterns. Second, the bar charts summarize sightings within any radius you select from 1- 50 miles or km. The bar charts include sightings at hotspots and personal locations, except those that are unconfirmed or hidden by the user.
The red vertical line on the calendar helps orient you to the current date so you can quickly see the expected current abundance for each species. Additionally, you’ll notice a small red dot along the bottom line of the chart. This dot reflects the most recent sighting within the area covered by the bar chart. For common birds the red dot is normally at or near the red line.