Global Big Day

What is the Global Big Day?

The Global Big Day is an annual event hosted by the Cornell Lab of Ornithology aimed at observing as many birds as possible within a 24-hour period. More than 35,000 people participated last year in more than 175 countries around the world, and 75% of all bird species were observed!

This year’s goal is to submit over 100,000 checklists in a single day. Join the effort alongside thousands of volunteers, communities, academic and governmental organizations, and conservation groups like ADOPTA to make this year even better than the last!

Save the Date:
May 9, 2020
Save the Date:
May 9, 2020
Gray-cheeked Nunlet
Nonnula frontalis

How to Participate

It’s easy to participate in the Global Big Day, but please remember to always put safety first and follow all local safety guidelines and closures in these uncertain times. Luckily, birding can be done from any location–you don’t even have to leave your house! Here’s what to do:

1. Make an eBird account at

eBird is an amazing tool for citizen science that allows everybody's observations to be easily compiled and make the data available to scientists studying birds. Don't worry–it's 100% free!

2. Find a comfortable spot to watch, listen, and record.

All sightings count from midnight to midnight the day of the event. Aim for observations between 10-60 minutes, with about 20 minutes between each list.

3. Submit your observations to Cornell's eBird website or through the eBird phone app

Count all birds you saw or heard, and add photos if you have them! If you're having difficulty with identification, try Cornell's Merlin app; information about both eBird and Merlin can be found below.

If you have the time, submit multiple checklists throughout the day to see if the birds you’re encountering change. When do you notice more activity?

The Cornell Lab of Ornithology maintains a digital platform called eBird used to promote public participation in birdwatching and record bird sightings. More than 650 million observations have already been uploaded to eBird by citizen scientists to help us better understand population changes and migration patterns around the world!

This app/website is free to use, and is the official platform being used to record sightings for the Global Big Day.

The Merlin Bird ID app is built to help identify birds using descriptions, photos, or probable local birds. With information backed up by millions of eBird sightings, this app is like having a field guide to the birds of the world in your pocket!

Good Luck Out There!