I’m in southern Indiana and have been noticing far more monarch butterflies this fall than I recall seeing in previous years. On September 27th I was at an old field with lots of goldenrod in bloom and I must have seen more than a hundred monarchs hanging around. Where I live on the edge of a small city I’m also seeing numerous individuals on a daily basis. A few other people I have talked to have likewise been surpised at the population numbers. Has anyone else had a similar experience or have I just been in the right places at the right times?
Same for me here in the mountains of NC - I’ve seen more monarchs, both caterpillars and adults, over the last few weeks this year than during the last four years combined.
You can go to the Monarch taxon page and confirm that with iNat’s data. Click on the History chart. It defaults to not showing the current year, so you have to drag it to the left a bit. When you do that, you can see that the peaks for the last six years have been pretty steady, between 9,000 and 11,000 observations. This year’s peak jumped to over 24,000. Amazing!
To use iNat data to compare abundance trends, you really should adjust the data for sampling effort. The easiest proxy for that available on iNat is the total number of observations for a given month. The history plot does this for you, if you click on the little gear icon in the top right corner of the chart and choose “show relative proportions …”:
You can see that 2025 is indeed higher than recent years (almost twice that of 2024), but not as high as 2019 and earlier, so the interesting thing might be why there was a decline during 2020 – 2024. (Of course, this may all be due to shifts in the interests of iNat observers, rather than any real trends in monarchs - I’ll leave the real trends to the monarch conservation biologists.)
I know that the number of observations on iNaturalist have been increasing every year, so I was thinking in terms of “adjusting for inflation”. (Amateur naturalist here, so I don’t always know the correct jargon to use.)
I didn’t realize this feature was already built into the site. Thanks!
Man, I am glad the data backs this up because I was just going to come in with my anecdotal evidence as well from our yard. I kinda regret not being more thorough with documenting more that came through!
Adding, I also saw a video on youtube, from the Rockies I think, that had a woman sitting on the tippy top of a mountain just absolutely surrounded by migrating monarchs. It reminded me of bird migration with how many individuals there were!
It’s gratifying to hear that both individual experiences and the data seem to support the notion that they are having a good year. Monarchs can certainly use some good news. I wonder what is driving it.
