Thursday, August 26, 2010

Rough Greensnake

Last Friday night, I led a nighttime singing insect walk at Buzzard Roost Preserve in Chillicothe. This is a fabulous natural area, sporting some 1,200 acres of varied habitats. We always see interesting things here, and this walk started out with a bang. As I neared the preserve, I began to notice hundreds - thousands, probably - of Common Green Darner dragonflies in a massive feeding swarm along Polk Hollow Road. When I arrived at the parking lot, above, there were dozens of darners hunting here, too. This has apparently been an exceptional late summer for migrant dragonfly hordes.

Anyway, our primary purpose was to learn about the Orthopterans - the primary group of "singing" insects. We saw some and heard hundreds, representing many species. This is a female meadow katydid; note her long sword-like ovipositor. We heard several species of meadow katydids, and their relatives the Greater and Lesser Anglewings, Common True Katytdid, and Round-tipped Conehead, among others.

This is a tree cricket, perhaps a Two-spotted Tree Cricket. We heard those, as well as Broad-winged and Davis's Tree Crickets, and several other types of crickets.

Lots of other cool stuff of the night popped up, including this walking-stick, a true master of camouflage. This one was about four inches long, and they look all the world like twigs.

Caterpillars really come to life under cover of darkness, as the birds, parasitoid flies and wasps, and other predators have retired for the day. These are Fall Webworms defoliating a Black Walnut tree.

But here was the real surprise - a true bonus. One of our sharp-eyed participants spotted this Rough Greensnake vining its way through a thicket of grapes.

Greensnakes are most active at night, and they aren't easy to spot in the shrubbery. They are mostly arboreal, gracefully slithering through the foliage seeking insects and other prey.

Exceedingly gentle, greensnakes do not bite and even people who are frightened by snakes are often mildly charmed by these interesting little serpents. Note its huge eye - an adaption to a nocturnal life style.


Buckeyeherper said...

Awesome. One of the many herps I miss now living in Michigan. There are a few studies that talk about the ease of finding rough greens while spot lighting at night along lake shores. Unfortunately, I or my close friends were never able to replicate this. Rough greens are actually mostly diurnal, supposedly you spot light them while sleeping at night. I have seen many, all have been active during the day or DORs. It is neat this one was active at night. Just goes to show herps don't always read the books.

Anonymous said...

I use black walnut leaves to rear Saturniids(I have a crop of Lunas right now, but have also reared Cecropia and Polyphemus on it). Anyway, in gathering walnut leaves, I've found lots of other things feeding on it, and I believe your shot is not Fall Webworms, but Angus's Datana (check Wagner). They feed communally too, but are bigger, and have black bodies with longer, wispier hairs than the webworm. It didn't look like there were webs in the photo either. I love Rough greensnakes too. I have only seen them on 2 occasions, both by the dam at William Harsha Lake(East Fork) in Clermont County back in the mid-90s.

Brian Menker

Jim McCormac said...

Thanks for the comments, all. I appreciate the info about the caterpillars, Brian. Your ID certainy looks good to me!

Also, Wil Hershberger sent me a note saying that the tree cricket is probably a Broad-winged and his explanation certainly makes sense.

Buckeyherper, hadn't heard that about Rough Greens being mostly diurnal. I've now seen a few out at night and they seemed active. And with that big honking eye it certainly looks like they are equipped for the dark of night. I wonder if perhaps the Smooth Greensnake is perhaps more diurnal...

Anyway, I love to learn about all of this stuff and really appreciate feedback and good information!


Anonymous said...

I didn't have my copy of Wagner's caterpillar book with me when I typed that. I looked today and I still think it is one of the Datanas, appropriately enough the Walnut Caterpillar- instead of Angus's Datana. I forgot Angus's has white stripes along the body.

Buckeyeherper said...

Most of the local references discuss the diurnal lifestyle of the rough green (Minton's Indiana herp book, Wynn/Moody's Reptile atlas, Conant) but they definitely do turn up at night. There is also probably some seasonal variation to their activity patterns. I don't have nearly as much experience with smooth greens (just a handful of individuals from a NE Ohio local) but I would imagine they are more diurnal.

Jared said...

I don't have much experience with Rough Greens, although I've seen one diurnally active in South Carolina, and a couple dozen in southern Illinois. Perhaps those large eyes equate to a better-developed sense of sight and less reliance on tongue-flicking for finding prey (insects)?

I've seen about fifteen smooth greens now and they seem quite active during the day, including a very fresh DOR midday. I've never heard anything about either of these species being nocturnal so your findings, Jim, are pretty cool.