Saturday, April 2, 2011

They're back! Wood Frog reproduction, part 2

A couple of weeks ago, as you may remember, I came across some Wood Frogs just waking up and beginning their breeding season, and I was very excited. With the very cold weather that followed, however, the frogs disappeared, and since I only found a few egg masses after that, I was wondering if the frogs would return for a second round of reproduction.

Well, I'm happy to report that Part Two of the Wood Frog mating frenzy is currently underway, with new egg masses already showing up in the pools I visited this morning! One pair of Wood Frogs let me sneak up very close to them so I could take a picture (you can see even more detail if you click on the picture to zoom in):

Now, lest anyone should feel squeamish -- I showed this picture to Paul, and his first reaction was "Ah, why would you show me that??" -- I might point out that the mechanics of amphibian breeding is quite different from that of, say, mammals. Frogs will stay clasped together like this for hours, and the fertilization process is entirely external -- the female lays her eggs in the water and the male deposits his sperm over them (that's why the smooshy, semi-permiable outer membranes of amphibian eggs are so useful). And it's not exactly a private affair, with all those pairs of frogs sharing the same pool. So there's nothing indecent going on here, just frogs being frogs.

Also, I love the color contrast between the male and female in the picture. Never having seen multiple Wood Frogs together in one place outside of breeding season, I don't know whether they're always so differently-colored, or if this is a special seasonal thing. What a beautiful orangey-brown color the female has, though!

In another pool, I found some very different-looking egg masses (and maybe it's not even useful to include this blurry picture here, but there you go). My guess is that these are Spotted Salamander eggs, which I base on the following reasoning: (1) Spotted Salamanders are supposed to start breeding around the same time as Wood Frogs, (2) these masses had a thick "jelly" layer surrounding them, which is characteristic of salamander eggs, from what I've read, and (3) I found the (dead, partially-eaten) remains of an adult Spotted Salamander under a tree nearby. That last part was a pretty sad discovery, because I love these little creatures, and I haven't actually seen one in many, many years. But if these are indeed salamander eggs, then I'll be curious to see what happens with them -- perhaps there will be salamander larvae swimming in these pools before too long!

So all in all, it was a great day for amphibians. I definitely did hear some scattered Spring Peepers calling today as well, but I didn't have any luck locating the little guys. And in conclusion, amphibians are awesome. :D


  1. This was so enjoyable to read. We have tree frogs all over the place here in north Florida (none yet). I usually hear them (hundreds) or see their bellies as they cling to my windows at night. I can't wait to tead more.
    Chris Horvath

  2. Thanks for your comment, Chris! Wow, I'd love to have tree frogs climbing on my windows! Paul also tells me that you have alligators in your yard, though, so I don't think that would balance out for me. :P