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.
Comentarios
Thanks, Jim. Interesting stuff!
Jim, Thanks. Love it!
Super stats. We are the best!
Appreciate it Jim!
Thanks Jim . Cant wait for warmer weather !
Always interesting stats. Thanks Jim.
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