Happy Ground Hog Day!

Feb 2, and we're expecting some winter weather over much of the state. No Dragons or Damsels, but the nymphs/naiads are in their watery niches waiting for warmer days.

One of the things I think about is comparing Odonata recent years to the past. Given the volume of new observations since 2017, this is a bit of a challenge. We can now get more data points in 1 year than we had in the first 100 years of the Ohio Odonata Society. Certainly some things have changed. A number of species recorded in the past have not been seen in the last 5 years, but we also have a number of species that are new to the state. Some of the not-documented species were always rare, so comparing 127 years to the last 5 isn't the best fit. I'll be working on this.

For now, let's consider some things that appear to be consistent. Numbers pick up considerably in May, then peak in June and July. This makes some sense. Both recent years and historical records show species diversity peaking in early to mid June. July continues with good numbers on total observations, but slightly lower species numbers.

Here are species counts by month.

Month pre-2001 2001-16 2017-20 2021
Mar 7 6 5 1
Apr 18 22 28 13
May 107 93 99 79
Jun 144 129 133 118
Jul 138 122 121 97
Aug 113 98 94 79
Sep 91 76 78 69
Oct 48 37 61 40
Nov 13 8 13 8

Here are record (observation) counts by month.

Month pre-2001 2001-16 2017-20 2021
Mar 9 11 14 14
Apr 81 106 487 219
May 1877 1118 6207 2264
Jun 7089 3600 21901 8300
Jul 7518 2789 23499 6649
Aug 5063 1736 18236 4516
Sep 2359 1028 8199 2964
Oct 619 255 1832 1046
Nov 49 73 181 260

The takeaway here is get out to your wetlands in early June - you're likely to see more species than any other time of year.

I'll be putting some charts on the Ohio Odonata FaceBook page if you're interested.

Another point of continuity is more observers in more counties leads to more observations and species. We have matched or surpassed the number of counties with observations by month in recent years, and have swamped the number of individuals contributing to the data. In both June and July of 2021 we had over 500 different people reporting observations, the first time we've had 500+ in a month.

Posted on 02 de fevereiro de 2022, 09:49 PM by jimlem jimlem


Thanks, Jim. Interesting stuff!

Publicado por lgilbert cerca de 2 anos antes

Jim, Thanks. Love it!

Publicado por sallypsandpiper cerca de 2 anos antes

Super stats. We are the best!

Publicado por nnavarre cerca de 2 anos antes

Appreciate it Jim!

Publicado por rickbarricklow cerca de 2 anos antes

Thanks Jim . Cant wait for warmer weather !

Publicado por mark3939 cerca de 2 anos antes

Always interesting stats. Thanks Jim.

Publicado por monicap273 cerca de 2 anos antes

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