I was recently given some shed snake skins that were found at the CWRU Farm in northeast Ohio. These sheds will provide a fun way to teach CWRU herpetology students snake identification skills. Shed snake skins have a number of characters that can be used to identify the species of snake.
I looked closely at the scales to determine whether they were keeled or smooth. Keeled scales have a small ridge running down the middle, whereas smooth scales lack the ridge. By examining this close-up view of the scales in the photo of this shed, you can see that they are smooth. Since this shed has smooth scales, we can rule out several additional species, including the Northern Water Snake and the Garter Snake. We can also rule out the Black Rat Snake, as it has weakly keeled scales.
This leaves a couple snake species that could be the source of the shed: Eastern Milk Snakes and the Black and Blue Racers (which are geographic variants of the same species). To separate the remaining snakes, we need to look at the anal plate. The anal plate is the last of the large belly scales on the snake’s body, and it is located directly over the snake’s cloaca (excretory and reproductive orifice). The photo below shows the anal plate (circled). In this photo, the snake’s head would be to the right, and the tail would be to the left.
As you can see from the photo, the anal plate on the shed is single, not divided. Racer snakes have divided anal plates, but Eastern Milk Snakes have single anal plates. So this snake ends up as an Eastern Milk Snake (Lampropeltis triangulum):
Here is one of two Brood V Cicadas that I spotted in a parking lot in Warrensville Heights, Ohio, on 19 June 2016. I’ve also recorded this observation in inaturalist. This is the first time I’ve seen these cicadas in my life, so it was pretty exciting!
Adult Bullfrogs are the largest North American frog, and even their tadpoles can be a handful. But they start their lives at a much smaller size. Here are two photos showing one day’s development of a bullfrog egg. The first photo shows a bullfrog egg about one day after it was laid, and the second photo shows a bullfrog egg about two days after it was laid.
A couple years ago I posted about leeches eating frog eggs. This year I spotted a struggling juvenile green frog floating near the surface of a pond. It was partway through metamorphosis, with all four legs, but also a long tail. As it slowly rotated in the water, I realized a large leech was attached to its side. I suspect that the green frog may have ultimately been killed by the leech.
On the same day, I spotted this big male green frog. There are variety of ways to tell a frog’s sex, such as looking at throat color, or for the presence of nuptial pads. In the case of green frogs, mature males are identified by the large size of their tympanum. And right above this male’s tympanum is perched a hungry mosquito.
May has been a great month for observing calling frogs in northeastern Ohio. Here are a couple videos taken in the last two weeks. The videos show Gray Treefrogs and Green Frogs. You can also hear American Toads and Spring Peepers in the background of some of the videos. Spring Peepers are one of the earliest-breeding frogs in the midwestern United States. They were calling in early March this year. But by May, there were just a few males still hanging out and calling. American toads have had a prolonged calling period this year, with calls ranging from late April through late May. But they seem to be finishing up now in northeast Ohio.
The Gray Treefrogs will continue to call through June and even July, depending on the weather. The Green Frog will also continue to call for several months, perhaps even into September.
mister-toad.com is the personal website and blog of Mike Benard, a biologist who studies the ecology, evolution and conservation of amphibians and other organisms.
Mike can be contacted at: mfbenard -at- gmail . com.