Sunday, October 16, 2011

Turtles About Town

I got my turtle fix over the weekend. I went on a Big Brothers Big Sisters (BBBS) nature walk at the John Heinz NWR on Saturday (thanks to ranger Mariana Bergerson for a great tour). The weather was crisp and sunny, and that was enough to bring out the turtles.

The first two we spotted were red-eared sliders (RES - Trachemys scripta), descendents of released pets of a species native to the middle part of the country, not the Delaware Valley. RES are kind of like the methadone of turtle fixes. They ease the craving but don't quite get you high. Maybe if they looked better they'd hit the spot, but they're such basic turtles that, as they get older, end up rough and dull looking.

Here's a mystery turtle that I think is an RES.

The real release came with a proper Delaware Valley turtle, a hefty red-bellied turtle (Pseudemys rubriventris) basking with some smaller turtles that I think are the same species. There is a lot of concern that the RES are pushing out our red-bellies. RES are getting more common; our beefy red-bellies are growing scarce. Cause and effect, or both effects of a common cause (for example that RES might thrive better than red-bellies with human-altered habitat)?

It was satisfying as well to see some painted turtles (Chrysemys picta), the girl next door of our native turtles, the one who you see so often that you forget how pretty it is until one day you look and...

The Heinz NWR might be the most dramatic wild landscape in Philadelphia; Concourse Lake sits on the other end of the majesty spectrum. This is an artificial pond in Fairmont Park West dating to the Centennial celebrations of 1876. There are some snappers (Chelydra serpentina) in there, and catching one is high on my priority list for 2012, but the turtles you see most often are the RES.

I want to send out a hearty congratulations to Fairmount Park (or Philadelphia Parks and Recreation, now that they've merged) for a job well done here. They took an ugly, foul, decrepit pond that even I was scared to touch and re-paved the paths, added a lot of attractive native plants, dredged out one side of the pond to make it deeper, and left the dredged fill on the other side to create a wetland area. Apparently the Canada geese like to rip out the plugs of native wetland plants they use to get the vegetation started, forcing the landscapers/restorers to use tightly arrayed fencing to keep the geese out: