northeast-flora-and-fauna

Here's a River Cooter along the Delaware Raritan Canal last May. I'm going to try and explain how I arrived at this identification. Despite living in New Jersey, they're not documented in my Field Guide to Reptiles and Amphibians of New Jersey [1], so I went to the internet for some basic information . Here's what I can tell you: The plastron is yellow, not reddish-orange (female) or pink (male) that you would expect to see in a Northern Red-bellied Cooter . Also, Northern Red-bellied Cooters frequently have jet black heads and necks, while this turtle has noticeable yellow there. The carapace lacks the prominent lines around the scutes that you'd see in a Painted Turtle . It also lacks the rich tapestry of lines on the head/neck that you'd see in a Common Map Turtle . A Red-eared Slider normally has a prominent red blotch about where you'd expect an ear to be, and a Yellow-bellied Slider should have a prominent yellow blotch in that same spot. I also thi...

I read today that there is some sexual dimorphism among our Northern Red-bellied Cooters . Though in many of our turtles the females tend to be larger, in Northern Red-bellied Cooters the difference isn't great; a large male and a medium-sized female are probably going to be about the same size, and unless you see turtles pretty close up, judging subtle size differences can be error prone. But this article suggests that it's the females that have the distinctive reddish-orange plastrons while the plastrons of the males tends to be pinkish. And my field guide says that while the sides of the females look striped, the sides of the males look more mottled. That's why I'm suspicious that the 1st turtle below is a female and that the 2nd turtle picture is of a male (with a friend). Bright orange plastron + stripey side = Female March 16, 2023 at the Raritan Water Power Canal Photo 267710927, (c) jpviolette, some rights reserved (CC BY-NC) The presumed male Northern Red-bel...

Basking turtles - turtles who like to bask in the sun - are frequently found together, sometimes in pretty close quarters crowded on a log or a rock. Wikipedia suggests that a group of turtles is called a bale. This picture represents the Basking Big Three turtle groups [1] around here: Sliders - The top turtle is a Red-eared Slider , a species introduced to this region from other parts of the country. There are concerns that they might out-compete our truly native turtles, though right now we have plenty of other turtles. Pond Slider is the common name for the species, and around here the Red-eared Slider is the most commonly spotted subspecies. Painteds - The 2 turtles in the middle are Painted Turtles, probably Eastern Painted Turtles , our most common Painted Turtle. They have smooth (sometimes shiny) carapaces segmented into easily distinguishable scutes . Painted Turtle is the species name, while Eastern Painted Turtle refers to a particular subspecies. Cooters - The large t...

Here's someone that, according to my Field Guide to Reptiles and Amphibians of New Jersey, doesn't exist here: a River Cooter . For years I didn't realize these turtles were in NJ, though iNaturalist would frequently offer this as an ID for some of my pictures. Apparently this generally southern species has been in my state for decades (though perhaps in small numbers and a few localities). Their existence does complicate the turtle identification process here, especially between the cooters and the sliders. It's not entirely clear how they got here, though some form of human introduction seems most likely. Their original range was considered to be as far north as Maryland though, so a gradual natural range expansion could also be plausible. FWIW, iNaturalist does not list them as an introduced species. I have certainly encountered their relative, the Northern Red-bellied Cooter , which is listed in my field guide as NJ's largest "basking turtle" (turtles...