A Big Year is an attempt to find as many bird species as possible in one calendar year within a chosen area. It shares the calendar with two other year-long games: the Bird-a-Day challenge, where you log one new species each day until the first day you can't, and the 365-point calendar, where every date has an assigned bird. All three start on January 1, but they reward different things.
The three games at a glance
| Big Year | Bird-a-Day | 365-point calendar | |
|---|---|---|---|
| Goal | The most species in one calendar year | A new species every day, for as long as the run lasts | See each date's assigned bird on that date |
| What scores | Every species new for the year, on any day | One species per day; each species can be used once | 1 point when you see the day's bird |
| A day with nothing new | Adds nothing; the year goes on | Ends the run | Scores 0; the game goes on |
| Maximum | No fixed ceiling; depends on the area | 365 days | 365 points in a non-leap year |
| Rulebook | ABA Area Big Year Rules and ABA Recording Rules, for lists submitted to the ABA | None official: "there's no such thing as the 'bird-a-day' police" (Audubon) | The organizers' calendar page; players keep their own score |
| Area | Your choice: ABA Area, state, county or yard | Your choice | Birds chosen for the continental US |
- Big Year: every species new for the year counts, on whatever day it turns up. A quiet day adds nothing, and nothing ends the year before December 31.
- Bird-a-Day: exactly one species per day, never repeated. Extra species seen that day don't score.
- Run ends: the first day with no unused species ends the Bird-a-Day run.
- 365-point calendar: each date has one assigned species, and seeing it that day scores 1 point.
- Miss: not seeing the day's bird scores 0 points; the game carries on the next day.
What counts in a Big Year
There is no single Big Year, because you pick the area. Writing in Audubon in January 2017, Nicholas Lund suggested that instead of a continent-wide chase "you could focus on your state or county or even backyard." The best-known version is the ABA Area Big Year. The American Birding Association's rules say that "any ABA Area Big Year lists submitted to the ABA" must follow them:
- Time. From 12:00 AM on January 1 to 11:59 PM on December 31, in the birder's local time.
- Encounter. Each species must be encountered under the ABA Recording Rules in effect at the time.
- Checklist. The species must be on the ABA Checklist during that year. A species added by a split counts for that year whenever in the year it was seen; the ABA's example is Pacific Wren in 2010. A species removed later stays counted for the years it was on the list; the example is Crested Myna, removed in 2003.
- New species. A non-exotic species new to the ABA Area can be counted retroactively once it is added to the checklist, if the bird seen is the accepted record or a later one.
The ABA Recording Rules (version 2020) decide whether one bird is countable. It must be within the area and time period, belong to a species on the checklist, be "alive, wild, and unrestrained," be identified by diagnostic characteristics seen, heard or documented, and be encountered under the ABA Code of Birding Ethics. A heard-only bird counts if its sounds are "sufficiently distinctive to distinguish the bird from all other species." A bird seen only on a webcam does not. The ABA codes page shows how often each checklist species turns up.
Hawaii. The ABA voted in October 2016 to add Hawaii to the ABA Area. Audubon reported that this could add as many as 115 birds to the checklist. Some birders now give two totals: "Classic" for the old area and "New ABA" including Hawaii.
Big Year records, as the sources report them
Totals change after the year ends, as committees rule on provisional species (birds not yet on the checklist) and splits change the list. Each figure below is given as its source states it.
| Year | Birder | Area | Total | Notes |
|---|---|---|---|---|
| 1998 | Sandy Komito | ABA Area (before Hawaii) | 748 | Audubon (2014, 2016). 10,000 Birds (December 2013) gave "745 (+3)": three species were not yet on the checklist |
| 2013 | Neil Hayward | ABA Area (before Hawaii) | 749 | Audubon's 2014 profile gives 749 and 750 and notes three provisional species awaiting approval; Audubon (2016) and a 2017 news report use 749 |
| 2016 | John Weigel | ABA Area | 780 | Official ABA tally reported in early 2017. Weigel's own January 2017 wrap-up: 783 "Classic" plus 52 Hawaii species = 835 "New ABA"; Wikipedia lists 836 |
| 2016 | Olaf Danielson | ABA Area | 776 | Same 2017 report |
| 2016 | Laura Keene | ABA Area | 759 | Same 2017 report |
| 2016 | Christian Hagenlocher | ABA Area | 750 | Same 2017 report |
| 2015 | John Sterling | California | 490 native; 500 with 10 introduced species | Godwit Days article (2017) |
| 2015 | Noah Strycker | World | 6,042 | eBird (January 2016): 41 countries, heard-only birds counted. Clements taxonomy; 6,153 under the IOC list (Audubon, 2016) |
| 2016 | Arjan Dwarshuis | World | 6,852 | Guinness World Records, IOC list; updated to 6,910 as of December 2021 after taxonomic changes |
The 2017 report quoted the ABA's Nate Swick: all four 2016 record-breakers had also seen a few birds still under consideration, and their totals would be amended if those were accepted.
A record year is a full-time project: Audubon's 2014 profile of Neil Hayward lists about 193,758 miles flown, 51,758 miles driven, 147 hours at sea and 195 nights away. It noted that only 14 birders had ever passed 700 species in a year. When Weigel and Danielson both passed 750 in July 2016, Noah Strycker pointed in Audubon to recent splits, such as Western Scrub-Jay into California and Woodhouse's Scrub-Jays, and to the strong 2016 El Niño.
Wikipedia (a secondary source) traces the North American record back to Guy Emerson's 497 species in 1939. For state lists, see the year in review.
The 365-point calendar: two descriptions
Audubon's 2017 Bird-a-Day article describes a calendar by University of Connecticut professor Morgan Tingley that "riffs off a Sibley desk calendar." According to the article, it groups birds by season, gives points by rarity, and has players "aim for 365 points." The calendar page on Tingley's website, which calls the game the Bird-of-the-Day Challenge, describes the current version differently:
- "Every day of the year has 1 bird. If you see the bird on that day, you get 1 point." Every bird is worth one point, up to "a maximum of 365 points" in a non-leap year.
- Each day's bird is drawn at random, with a probability that follows how likely the species is to be seen and reported on that date anywhere in the continental US. A rarity score from 1 (most probable) to 5 (least probable) is shown for each day's bird but does not change the points.
- It grew out of a 2016 competition played with a Sibley calendar ordered by taxonomy rather than season. The page offers the 2025 calendar as a PDF or calendar file, with archives back to 2017. Players keep their own score.
The two sources differ on rarity points. This page follows the calendar's own rules, which are the more recent and more detailed description.
Which game fits your year
| If you… | Consider | Why |
|---|---|---|
| Can bird a little every day but rarely travel | Bird-a-Day or the 365-point calendar | Both reward daily effort rather than distance |
| Want one number to beat at year's end | A state, county or yard Big Year | The alternatives Audubon's Lund suggests to a continent-wide chase |
| Travel and like chasing rarities | An ABA Area Big Year | A Code 5 vagrant counts the same as a common feeder bird |
Playing all three at once
The games don't conflict, so the same sightings can feed all of them.
- Write your house rules before January 1. Set the area, decide on heard-only birds, and say whether you follow the ABA Recording Rules.
- Log checklists in eBird. eBird updates life, year, county, yard and patch lists automatically, so a Big Year list builds itself. See eBird for beginners.
- Pick each day's Bird-a-Day species in the evening. Audubon's advice is to use the most unusual bird of the day. Record it in the streak tracker.
- Check the calendar bird and give yourself the point if you saw it.
- Plan scarce birds with the species planner. A Big Year only needs each species once, but Bird-a-Day rewards using it on the right day.
Quick checklist
- I have chosen the area for my Big Year list (ABA Area, state, county or yard).
- I know which checklist and Recording Rules my list follows.
- My Bird-a-Day house rules are written down.
- Provisional species are marked separately on my list.
Sources
- ABA Area Big Year Rules — American Birding Association
- ABA Recording Rules and Interpretations (version 2020) — American Birding Association
- Boost Your Birding Skills by Seeing a New Bird Every Day This Year — Sharon Stiteler and Purbita Saha, Audubon (January 6, 2017)
- What is the bird of the day challenge? (Bird-of-the-Day Challenge calendar page) — morgantingley.com
- Birdist Rule #99: Make Some New Year's Birding Resolutions — Nicholas Lund, Audubon (January 5, 2017)
- Hawaii Counts: Meet 10 Island Birds Now Eligible for Your Life List — Kim Steutermann Rogers, Audubon (December 22, 2016)
- King Bird (profile of Neil Hayward's 2013 Big Year) — Matthew Power, Audubon (July–August 2014)
- Two Guys Just Broke the North American Big Year Record. How? — Noah Strycker, Audubon (July 26, 2016)
- The ABA Area Big Year Record Is Tied — 10,000 Birds (December 19, 2013)
- America's toughest record in competitive birdwatching was shattered last year — Mitchell Republic (2017)
- 2016 ABA Big Year Wrap-up — John Weigel (January 2017)
- The Many Shapes & Sizes of a Birding Big Year — Rob Hewitt, Godwit Days (2017)
- Noah's 2015 World Big Year Summary — eBird (January 24, 2016)
- Noah Strycker's Global Big Year Record Has Been Broken — Noah Strycker, Audubon (November 17, 2016)
- Most birds spotted in one year (individual) — Guinness World Records
- Tracking your lists with eBird — eBird
- Big year — Wikipedia (secondary)