Friday, May 29 started out with some great weather (sunny and calm) so I headed to
Lower Huron Metropark at 1000 to obtain physical evidence of the spiketails.
Initially, I walked the forest edge in hopes of finding an adult Arrowhead Spiketail (
Cordulegaster obliqua) to photograph. Unfortunately, I only saw one and it did a quick flyby at head height on the opposite side of the clearing and it didn't return.
Thus, it was time to check the rivulet.
Ethan Bright hinted that I should dip for nymphs in the silty areas below the sticks and branches laying over the water of the streamlet. On about the sixth dip, I came up with a large nymph of a
Cordulegaster.
![](https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgnROZTkoIELehYckGvrQAz7pqueuXlv3V3mghew7ApQgU2BWvx6wCxl-7WPOLBFdrdozCBf216_hIWiOVRs1qOSKGDiIS1hnXs_CZlThFcC8od7zkzRnZd2R1s6xoe7tkoWZGnVQ/s320/3576586623_2b54f61794.jpg)
This is the home of this nymph.
![](https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjJ8Z5utctSNuVZfeWVb8U6ZAecLwO9o40P9a_IgAEGG0LlKXy25rJ-kvClOhzfrovWsN0Xjlfy4-jyYqxTeS29q7UnYj5AeQXhs89fdWuJQ03O9Z9sWuhyphenhyphen_CzNthqQO35CsdvY5w/s320/3577379806_4b591eaf82.jpg)
After identifying the specific structure of the nymph habitat, I began looking for exuvia. At 1130 and a bit upstream I "hit the jackpot" by finding an emerging female. Note the large ovipositor.
![](https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjRluNvMUNJQW_jeXn_efrLzu_AnAFWOIDA_NF3V9A0DsIyf9br2AEdJ1bjpfkmJeBTXlPdF51QUPaDo6I3CM-f0s7p7YipKf4bPQGq9tEd_VzXvTsxulYFpASUvQ3EhEfQjJXHSg/s320/3576578003_8d307f1bbb.jpg)
She was on a tree a few feet from the rivulet and is on the trunk at the left in the photo below.
![](https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjuTwOGGvl6Bkpc7nAAsqJI9lSsG8UAjSQyHKGuDaBJr1loezok3iJ3ltUqsZ4OvFUgf_nmRVhg2sWbo4kEjmJBrr4xO-oE6wZ-hLwSbF-x0lDPlTCMNtBjmT78J0UjAJhLf-nxcg/s320/3576580327_f7cdbbd63b.jpg)
Ethan Bright also noted that there may be different sizes of nymphs if these
Cordulegasters require more than one year to mature. A bit further upstream I dipped a few more times and found another nymph which was a bit smaller than the first.
![](https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjb-yYpqhE-wLH7qbhSXoA23fVjpgu9pnBe_lZk9Crfhp-HtV7D52XYQ5JoQlFfQYT-KZzLigO_bGKl-PQylIMOb2dTFaWofVi6m6k3IUalrky_Hf9lNowm1fdhfEzA46qHN62yoA/s320/3576585497_ff5304b992.jpg)
It was similar in habitat structure to the first, a hole below a log with a silty layer.
![](https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhSBsM_vgQJzEukiKIOe4r5Gv0k1RGl0swzBgtbkTbZ9BqDsRB68jQmnwGMW-bRzvICAD0p45eLRUfIsvTAeVMVfGJeEPHS8nybx1nOmaa9pwOIkJ5A-S48OzWYGpiz35Mz6ufNJw/s320/3577387232_70e209990e.jpg)
Given the couple of adults I observed over a few days and the nymphs being found relatively easily, it seems there is a decent population along this waterway. Nannothemis and I will return in a couple weeks to try and obtain good quality photos of the adults since there should be more flying.
![](https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEg7rH5BBcS6p6dfpPqTvefYcC2or0IBDxf9xwFuYYv2Ewfmoxs0dFSEp8E1pTo72Z5m6E1fGUFd_UuGGzvpDElZHKbDKx9HexEzqPcITKMOwDsNvI7ccUZ36fnMA-PMHa96FD1Nrw/s320/3576581617_3190a179c0.jpg)
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I returned on 31-May-09 and found one male perched in a calm, sunny area at 1115. I was able to obtain only one photo, shooting through my binoculars.
2 comments:
Congratulations on the discovery!
Thanks, john. Now the goal will be to get a good quality photo of an adult and to have Nannothemis see one. ;^)
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