Big Atlas Weekend - June 23-25, 2023

If this year’s “Global Big Day” didn’t fit into your busy spring schedule, here’s another chance to make your birding count! How about a Big Atlas Weekend? This exciting annual event is a fun way for birders from across the province to document breeding birds and come together as a birding community. For many birds in our area, breeding peaks in late June. It’s a great time to Confirm breeding and fill gaps in the Atlas dataset.

This event is being coordinated across four states and two provinces that are currently conducting breeding bird atlases—Newfoundland, Ontario, New York, Puerto Rico, Maryland and DC, and North Carolina.


  • June 20 @ 7pm EDT – Sappy Hour. We’ll be hosting a Sappy Hour on tips for atlassing in June and how to win the Big Atlas Weekend. [Register here]
  • June 21 @ 6 pm EDT – Kickoff. Introduction by the participating Atlas coordinators, followed by trivia! [Register here]
  • June 23-25 – Big Atlas Weekend! Go atlassing in any of the six participating states/provinces from 6 pm EDT on Friday to 11:59 pm EDT on Sunday.
  • June 28 @ 6 pm EDT – Awards ceremony. Enjoy highlights from the weekend, share your stories in small groups with atlassers from all states/provinces, and find out who won the individual and state/provincial champion awards. [Register here]

How to Participate

Go atlassing between 6:00 pm EDT Friday, June 23 and 11:59 pm EDT Sunday, June 25 and submit your checklist through the NatureCounts App or Web Portal. This video gives an overview of submitting data through the NatureCounts Web Portal, eBird import, and through the NatureCounts App

If you are new to atlassing, check out our Quick Start videos on YouTube or the website for more resources. If you’re an avid eBird user, but new to Atlas-3, check out our eBird and Atlas-3 page!

Challenges and Prizes

The Big Atlas Weekend will have prize opportunities for atlassers of all skill levels, ranging from first-timers to veterans. One prize winner will be randomly selected in each of the following categories to win a Cornell Lab of Ornithology Bird Academy course of their choosing. Each Atlas will also select an MVA–most valuable atlasser!

  • Species with breeding evidence reported that were not reported with breeding evidence in that square before the Big Atlas Weekend
  • Complete Atlas checklist with nocturnal effort
    • A complete checklist is one where you report all the birds you were able to identify and answer “yes” to the question “Are you reporting all of the birds you were able to identify?”.
    • A nocturnal checklist is considered to be a checklist that begins between 20 minutes after sunset and 40 minutes before sunrise
  • Complete Atlas checklist in a square with less than 20 hours of atlassing in the peak season
    • Peak atlas season is May 24-July 10 in southern Ontario, June 1-July 10 in northern Ontario.
    • A complete checklist is one where you report all the birds you were able to identify and answer “yes” to the question “Are you reporting all of the birds you were able to identify?”.
    • Explore the Atlas coverage map to see the amount of effort per square.
  • Post Atlas-related photos on Facebook, Twitter, or Instagram and tag the Atlas! (ONBreedingBirdAtlas on Facebook, ONBirdAtlas on Instagram and Twitter)


Get your swag on at TeePublic!

Who doesn’t love a bit of swag?! We’ve designed a logo for this year’s event that features the birds on each of the participating project’s Atlas logos. Order a t-shirt and other items from TeePublic. Proceeds go towards next year’s event.

Let’s all get out atlassing between June 23 and June 25 so that Ontario can claim bragging rights for the inaugural Big Atlas Weekend!

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