Sunday, April 25, 2010

Scott likes to talk about our white whales. I don't know if every single herper out there is obsessed with finding some critter in particular, but a lot of us are. A lot of us will make repeated trips to the same spot where someone's friend says he saw one ten years ago (maybe working on even flimsier data than that), or maybe we'll find perfect habitat for some rare, cryptic species and continue visiting it in the hopes that we'll be the first person to put that extra push pin on the map, to turn the potential into the real.

I have abandoned my white whale, gritting my teeth and withstanding the intense, internal compulsion to repeatedly go to Northwest Philadelphia - rocky hillsides in the Wissahickon and elsewhere in Roxborough or Manayunk where Philadelphia's milk snake (Lampropeltis triangulum) population resides. I know they're there - I found one in 2005, and Scott and I found one dead on the road (DOR in herper terms) a couple years ago. Friends who work for Fairmont Park report occasional sightings, as in 'Oh yeah, Bob saw one next to the golf course last year.' I've heard enough of those recent sightings to feel confident that there are a decent number of the snakes out there, but they've resisted my efforts since 2005 to find them intentionally.

Short of moving to one of those houses on Wise's Mill Rd. and hoping one will cross my path on my way out the door, I'm not sure that searching for them will yield any results. I can make another twenty trips and flip another few hundred rocks, and all I'll turn up is red back salamanders (Plethodon cinereus) and the odd ring neck snake (Diadophis punctatus). Milk snakes are like this - in some places you might find a whole bunch in one day, and then the rest of the year see no evidence of them no matter how hard you look (I've read this in books written by professionals, so it's not just my incompetence talking).

By frustrating contrast, there are also places where milk snakes are common AND easy to find, where 'that board' will almost always yield a strong, shiny milk snake with those beautiful red eyes. Scott and I now have one of those boards (actually a piece of metal), at a site we visit frequently to search for marsh wildlife. Give us mild temperatures and some sun to heat the metal, and we'll turn up one, maybe two milk snakes.

Here's one we caught there for an Earth Day walk last year - young and still looking sharp with the crimson pattern on the gray background.

Here's another we've found a couple times this year under that wonderful piece of metal.

Milk snake colors fade to brown as they age, but I'm pretty sure the shapes of their blotches and head patterns stay the same. After a lot of staring back at forth at the pictures, I'm pretty sure these are different snakes - both handsome serpents, even if the second one is a bit more orange. Along with another we found last year (with an distinctively different pattern) and a baby Scott has found this year, I think we've found at least four different milk snakes under this one piece of metal. I do feel that it's worth noting that we have never found any other milk snakes under any other piece of cover on the property, though the owners do report seeing them from time to time.

About that white whale - does finding milk snakes elsewhere satisfy my urge to find them in Philadelphia? Absolutely not. At every sunny spring day I still feel the very strong urge to drop everything and head to Roxborough.

I'll wind up with a spotted turtle I saw on the same property as the milk snakes. This is one we've caught four or five times by now. He started out at one location where we think they hibernate, and recently made a trip of about a hundred yards to another section of marsh.