Hidden Nests

I mentioned in a recent post that I have lately been crawling around in swamps throughout northwestern Massachusetts, conducting surveys for four-toed salamanders (Hemidactylium scutatum).  So I thought I’d take a moment on this cold, rainy day (not a particularly good one for conducting field work) to share with you what that entails.

As noted in this fact sheet, the four-toed salamander was taken off the state’s endangered species list seven years ago.  Part of the purpose of these surveys is to see how well represented this species is on protected land (state forests, conservation areas, etc.), and another part is to determine how well the known distribution in the western part of the state reflects the actual distribution.  Most towns in this region have never had a report of a four-toed salamander, and I believe that all of the wetlands I’ve been sent to are in towns where this is the case.

These aren’t salamanders that anyone is likely to stumble on without specifically seeking them out.  They spend most of their lives hidden in the ground, or under logs and other objects on the ground.  And whereas similarly secretive species like spotted salamanders can easily be detected by looking for their conspicuous egg masses in vernal pools, female four-toed salamanders make their nests under moss, in hummocks that are adjacent to small pools, into which the larvae wriggle upon hatching.  So surveying for this species involves picking through clumps of moss in the hope of uncovering a female or her eggs.

Well, I found some four-toed salamanders on the first day of surveying, which made me think maybe the apparent distribution gaps were just places where no one had looked before.  But then I visited another thirty swamps without any luck.  After that, I was pretty used to not finding anything, so I grumbled a bit at having to bushwhack for a mile off of a remote dirt road in order to explore what turned out to be a tiny winterberry swamp right next to a freeway.

This thicket wasn’t exactly easy to get around in, and didn’t seem very promising at first, but I found my way in, and was pleased to see that it actually had some pretty good habitat: little sphagnum hummocks surrounded by shallow water.

When I peeled back the moss in the hummock pictured above, sure enough, I found a four-toed salamander lying there among her eggs.

As with the first day, once I’d found the first salamander, every hummock or two of moss produced another one.  But apart from those two swamps, I’ve found nothing–just the occasional red-backed salamander pretending to be a four-toed, or a cluster of snail eggs posing as four-toed eggs.  We’ll see what the last week of surveys brings, but I’m beginning to think that at least in far western Massachusetts, this deserves to be considered a rare species after all.