Who holds the all-time record of most observations in a day?

Can one of the filter wizards make a list of the users who made the most observations in a single day, and how many observations they made? Maybe the top 10 or so?


This day is probably your best bet as it was the City Nature Challenge. Someone has 3249 observations from that day. That’s likely the record.
I don’t know if there is a way to make a list of the most observations in a day per person, but I do know that less than 100 people have more than 1000 on one day.


3249 observations but only 66 species…I’d be more impressed if the obs:species ratio is smaller, but that of course is not the focus of this topic.


why isn’t that the focus of this topic? why should we care that anyone was able to record a ton of observations in a single day at all?


  • do you define a day as a calendar day? or 24 hour period?
  • based on observed date? or submit date?
  • local time? or based on some standard time zone like UTC?

The question can definitely be further discussed with the prompts you suggested, but I was just being extremely literal about it (and based on the iNat filters I suppose a day is defined as a calendar day).

I’m curious how you know?

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I looked over the days that have high traffic(bioblitzes, city nature challenges, etc.), and looked over the rankings. Keep in mind getting 1000 observations means taking a photo(s) for an observation every 86 seconds. It’s pretty difficult.


I think that’s a good start! Looking at one of the high-count users shows many of the photos are of the same species with one photo per observation. Speculatively, maybe the observer:

  1. Uses a “keep taking photos while button is pressed” feature on camera.
  2. Bulk uploads with one photo per observation.
  3. Identifies each observation separately.

Nothing wrong with this, of course! Everyone has their own iNat workflow. I’m curious what the highest number of observations where there’s 2 or more photos per observation.


Interesting, if you view the observations for that user for the day via their calendar, it only lists 178 observations. Not sure what other filtering might be happening or why there would be such a difference: https://www.inaturalist.org/calendar/fseichter/2022/4/30

I had to look into it because as you pointed out, that many observations means an observation about every 27 seconds over a 24 hour period, which honestly just does not seem feasible. At least, not with those observations actually being useful. Especially for only 66 species.


Most species in a 24-hour period would be interesting to know. Basically a “Big Day” effort as the birders do, although all taxa and accompanied by voucher photos.


Most of the world’s population, including us, is tied for least observations in a day.


Looking through their observations that day it seems quite remarkable but true. It looks like they have wandered through a wildflower meadow and taken one photo of every specimen in flower they have seen - I can only see a couple of obvious duplicates - which is inevitable with that many. I could imagine taking one every five or ten seconds in this scenario. they are taken over a period of 10 hours - about right. looks like a sledgehammer strategy for city nature challenge - and they got 100 species from it (not sure where 66 has come from?). Presumably quite exhausting - power to them, I’m impressed.


I’ve broken the 1000/500 observations/species barrier once. @taitsougstad If you are going to break the record, you would need to visit as many different habitats as you can, taking photos of every species and organism, for the whole day. Finally, you would likely need to search for insects(especially moths) at night. 500 is difficult enough, 1000 is incredibly difficult, but 3500?
That’s basically impossible, especially with high species count.


Also, that would take over 12 hours to upload assuming 3 observations uploaded per minute.


That makes sense. If I snapped photos of literally everything I came across, every blade of grass every flower every… yeah I could do that.

I question how identifiable that would be though; I try to get multiple views, angles, closeups, etc. especially of plants, fungi, and the like that usually need a lot of info to ID well. Guess I could take photos of each blade of grass, each piece of clover, every mock strawberry, etc, in my lawn? I’d question the usefulness of that though.

I’m happy getting like 50 unique species a day, that’s a big day for me! Is there a way to find your personal day stats, actually? Not sure I’ve actually broken that barrier, maybe on a moth night.

Personally, quality over quantity. I’ll prolly never break a 1000 a day barrier because it takes me longer than 86 seconds to photograph most things.


Because it’s really cool info and people love statistics? This also shows why 66 species on 3k observations is quite funny for me, even if I observed each specimen I’ve seen in a day, that’d me much more than 66, did they even try? It seems impossible for me to achieve such ratio.

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One way is to use the calendar-option for your own observations. The darker the day is marked, the more observations. If you hover above it, it will show you the number of observations

My highlight was 189 obs with about 122 species this may in Colombia… I thought this might be the last phototour for me in quite a while and got a bit over board with it I guess…

Runner ups are 171:98; 147:84; 124:79 – all from vacactions at the red sea, which is just an amazingly crazy place AND 149:85 + 133:79 – from the first and last time I ever went to the rain forest in Ecuador

…just to put it into perspective… Those “above 100 observations”-outliers I have I can always pinpoint down to some special day

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really? even if they are sort of meaningless without context?

i guess if you really love statistics, below are the user / observed date (local time) combinations that have the highest observation count, based on an old copy of the AWS Open Data Set (from 2021-04-15).

the main limitation of this approach is that this would include only observations that had licensed photos as of that snapshot. so for example, if you compare the count of the first row in the table below vs https://www.inaturalist.org/observations?on=2018-06-05&place_id=any&subview=map&user_id=biobank-lantauhk&verifiable=any, you’ll see that there’s a 500 obs discrepancy probably due to a number of casual (no photo) observations. so the approach is not perfect, but it’s more efficient probably than trying to go through the API.

User ID User Login Obs Date Obs Count
547666 biobank-lantauhk 2018-06-05 3217
547666 biobank-lantauhk 2017-07-26 2740
20600 danielatha 2020-10-31 2155
25160 michaelbakkerpaiva 2018-06-29 1854
420537 astrobirder 2019-08-06 1665
20600 danielatha 2020-07-29 1543
420537 astrobirder 2020-01-05 1390
264009 ck2az 2019-06-19 1352
420537 astrobirder 2019-06-07 1346
20600 danielatha 2020-03-15 1339

(it may be interesting to note that none of the dates above seem to be from the CNCs.)

it someone wants to get stats using more recent data, they can get the observations metadata file form the latest AWS Open Data Set snapshot, index it on user_id and observed_on, and then run a query like this:

SELECT observer_id, observed_on, COUNT(*) as obs_count
FROM observations
GROUP BY observer_id, observed_on

You made me curious, so …

July 2 2021 in CO 207:123
June 27 2021 in NM 168:112
October 24 2021 in UT 153:101

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My record looks to be 145 observations of 122 species during this year’s CNC…