Tuesday, April 6, 2010

Four-toed Salamander

A beautiful vernal pool in Delaware County, Ohio. These wetland are quite alluring to salamander-seekers. I was fortunate in that Lauren Blyth, a died-in-the-wool salamander enthusiast, took me to see a couple of excellent and out-of-the-way vernal pools the other day. Our primary target? The odd, uncommon, and local Four-toed Salamander, Hemidactylium scutatum.

Vernal pools are wooded wetlands, typically rather small, and at their soggiest in spring. By mid to late summer they often lose all of their standing water. But spring is when most of the amphibians breed, and a number of species of frogs and salamanders gather in vernal pools to mate, lay eggs, and make more of their kind.

Four-toed Salamanders are probably the hardest of the vernal pool salamanders to find, and to successfully ferret them out requires some knowledge of their habitats and a lot of careful searching. They make their nests under moss on damp logs in the water; the moss-cloaked log above is a perfect example of this specialized breeding habitat.

Our quarry, a beautiful adult Four-toed Salamander. All of our other species have five toes on the rear feet; this one has but four as you may have guessed. It is not a large salamander, taping out at perhaps three inches on average.

If you are uncertain of the identification of a 4-toe, just turn it over. They are painted bold white below, and prominently speckled with blackish flecking. No other of our species looks anything like this on the ventral surface.

Nest with eggs. The female can be seen interwined with eggs in the upper right - she remains to guard them until they hatch, which takes about six weeks. More eggs can be seen on the left. The eggs aren't small, and it is amazing all of these come from her tiny body. Four-toed Salamanders are rather finicky about site selection, preferring older sheets of moss - the species of moss doesn't seem that important - that form loose drapes. The moss should also be directly over the water, so that when the tiny larvae hatch, they can drop directly into the water and thus probably greatly increase their odds of survival.

Researchers seeking this species need to be very cautious in their approach. Tearing around and ripping the moss off the logs is NOT the way to go about hunting four-toes. You might find some, but will also probably cause the failure of the nest. Rather, it is best to carefully inspect logs that appear suitable and gently tug the moss to see if it is loose. If so, slowly and gently peel it back and see if anyone is home. Lauren is very good at this, and she located five nests, and we didn't spook any of the salamanders. After we documented their occurrence the moss was folded back over the nest and all was well.

Four-toed Salamander, one of our most secretive amphibians. Given a good look, they are quite the charmers, though, and sport an interesting pattern of colors. They also typify the hidden but fascinating world of vernal pools, one of our most valuable wetland types.



Tom said...


Anonymous said...

Very interesting. Great Post.
Gary Wayne

Buckeyeherper said...

Excellent report. I would argue they are one of the easier salamanders to find though. In the right parts of the state, they are much more common than thought and their habitat can be easily spotted from afar. Often, if you find one, many many more will follow. I usually just locate one nest at each spot and then stop looking to try and preserve the moss. The caveat is you have to look in the right time of the year. I have never had luck finding them "out of season" in Ohio. Michigan on the other hand is a different story. I have flipped them under logs away from water in the middle of the summer and early fall.

Wonderful creatures. They are small, nondescript and not easily roadcruised though which makes them a little less desirable to the masses.


rebecca said...

Wow, that pond looks amazingly familiar - I went to Ohio Wesleyan University and did amphibian surveys in the area almost every spring, and I'm almost sure I went there with Sally Waterhouse at least once! (At one point I even went herping with my fellow Bishop Lauren Blyth - small world, or small state, anyway!) I remember finding a four-toed salamander in Wisconsin, the only time I've seen one, and thinking it was pretty awesome.

Russell Reynolds said...

Now ya done it Jim ,, now I got to go back across the road and check out the vernal pools back there I seen today when I was lookin' for birds. Your interests are very contagious.Russell