Ambystomatid question

[leanne]

This got me wondering after looking at Mike & Mark's Smoky Mtn. caudata photos----how come there are hardly any ambystoma to be found in this area, especially since it seems to be an ideal environment for such creatures?

(Message edited by tadpole on September 30, 2005)

 

[joan]

I think they're outcompeted by the plethodontids. I'm sure there are a few around, but there are massive numbers of plethodontids.

 

[russ]

No, it has more to do with collecting techniques and site selection. The season has a lot to do with it too. Most Ambystomids are only seasonally active at the surface, where as a lot of Pleths can be found year round as long as there has been sufficient moisture.

 

[joan]

Russ, is that true only in the mountains, or all over? I seem to find an abundance of ambystomatids (and the occasional plethodont) in Michigan, even in the fall. I've found hordes of blue spots, plus a few maculatum (Tigers being locally spotty, texanum being endangered, opacum being exirpated). Maybe this is just because there are more ambystomatids in Michigan than there are plethodonts.

BTW: I'm taking Jim Harding's herpetology class at MSU, yesterday was the lecture on Ensatinas as a ring species with some of your lovely photos.

 

[nate]

To chime in here along with Russ, it has more to do with season and locality. In general, Ambystomids (especially in areas with a lot of topography) are more fossorial than Plethodontids and are less likely to be uncovered by flipping rocks/logs.

 

[russ]

Wow, I'm honored someone used my pics. The speciation of Ensatina is very interesting (and complicated), especially having to take into consideration past climate changes and the possible paths of dispersal.

But no, I wouldn't say that my statement is a blanket one. Like Nate said, it is dependent of the location and species.

(Message edited by rust on October 01, 2005)

 

[leanne]

So Nate, generally speaking, ambystomatids are to be found burrowed pretty far underground? During the springtime after heavy rains, I have looked and looked for these guys in the mountain forest here in east TN---to no avail.

 

[john]

We've also find no ambystomids here. I've been extremely disappointed by that. My son would really like to find an Opacum. I'm hoping we'll be successful now that the weather is starting to change and they should be out of their burrows more often.

 

[nate]

When I lived in the Ozark Mountains of Missouri for around 7 years, I only found a single Ambystomid outside the breeding season by flipping a rock -- a male A. maculatum. But the ponds were full of larvae in spring and fall, so the animals were there, just apparently well underground.

In contrast, I could drive down to southeastern Missouri, where the terrain is much flatter and the water table much higher and find hundreds of Ambystoma in a few hours by simply flipping rocks and logs.