Hi, Fred - the most frequent snaky nest predator in our area is the Black Rat Snake, 
Elaphe obsoleta obsoleta. They are marvelous tree climbers, and can get up a pole to a 
nest box, too. Although the adults tend to be black on top with a white belly and some 
banding, the juveniles are light colored with grey, black and white bands. They are NOT 
venomous! 

Look here for a description of Maryland's snake species:
http://www.dnr.state.md.us/ wildlife/snakeinfo.asp

A good field guide for all the herps of this region is "Amphibians and Reptiles of 
Delmarva" by James F. White, Jr. & Amy Wendt White (see description at http://
www.delawarenaturesociety.org/merchandise/reptilebook.htm). It's available at the ANS 
bookstore (or online - but support your local book dealer!).

Mary LaMarca
Silver Spring, MD

On Tue, 19 Jun 2007 11:25:27 -0400, Fred Pierce <> wrote:

>Seriously - it looks like it's time for me to acquire one a them
>Herb's-tology books or whatever they're called. Can anyone recommend a field
>guide for the casual snakeophile? Right now I'm wondering what I just
>rousted out of the bluebird box that ate my House Wrens (that were inside
>the box, now inside the snake. I guess technically they were still inside
>the box, since the snake was). It (the snake) was light gray with whitish
>bands. Might have been black bands too - I wasn't prepared to encounter a
>snake and it didn't want to hang around for me to examine it.
>
>Thanks,
>
>fdp
>
>--------------------------------------------------------------------
>Fred Pierce (DNRC)- avialantic.com
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