Reptile & Amphibian Forums

This general area is in the range of T. sirtalis, T. butleri and T. radix, with a lot of intergradation. This shot is a dorsal view of a specimen I think exhibits mostly T. butleri characteristics

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Tim

Wide stripe, thick neck, little black on labial scales. Any comments would be appreciated.

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Tim

Tim, when I looked at the first picture from the top, I thought it was a butleri too, but from the second photo, the side view, it looks like a sirtalis. That wide yellow stripe seems to be on rows 2 and 3, but I'm not positive. Also, the head looks like sirtalis from the side.

In n.e. Michigan, at my study site, it's often really difficult to tell the sirtalis and butleri apart. Superficially, they look almost identical. I thought there was hybridizing going on for the first couple years, until I kept a few Butler's all summer. I still have to have them in hand much of the time to tell them apart, but now I don't think they hybridize, at least not here. I believe what's happening is that the sirtalis have adapted to the butleri habitat and have taken on their external appearance. They are so variable.

Here's a couple pics from my trip to Ohio a few weeks ago, when I met Mike M. We found E. fox snakes and these Butler's garters, along with a few other odds and ends. We were on the western end of Lake Erie.


The patterning on the neck, behind the head, is very typical of butleri.

Hope this helps a little.

TC

Yeah, this area is pretty wild because all three species occur together. Almost every specimen I find has characteristics of two, and sometimes all three species.

The site in question is at the northernmost range of T. radix. It's about 2000 acres, so there is a lot of variability. There are pockets of pure sirtalis present for comparison and their markings and proportions are very different from the specimen I have pictured above. Both snakes I have pictured are obvious hybrids. Almost every one I catch here is different.

I manage sites in five counties in SE Wisconsin, so there is a lot of opportunity for comparison. Pure T. radix in Kenosha Co (I got shut out yesterday though ), pure T. sirtalis in a lot of areas, and pure T. butleri in Ozaukee Co. and parts of Milwaukee and Waukesha Counties. My problem is that I haven't found a good pure population of T. butleri yet for comparison. I found a beauty in Waukesha Co earlier this year, but no camera.

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Tim

LOL...just kiddin'.

Sounds like you have a super site to study garter snake relationships in. Do you have any habitat pics? Where I just came from in Ohio, the habitat is typical for butleri. It's wet seasonally, especially in the spring from flooding. It also stays moist under the surface in summer, I believe important for Butler's because it keeps worms and slugs near the surface.

I have a little trouble with hybrids, because I don't believe species will cross, or rarely, unless they are very closely related. I think there's more chance butleri will cross with radix, because they are supposedly quite closely related.

I'd love to see the site, get some pics, and see some of these guys in hand. You've really got my curiosity up. Keep postin' pics if ya got 'em.

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Just looking, clicking, curious, studying, laughing, having fun, meeting cool folks, sharing. Live your dream, relax, smile, don't worry so much, love life. See ya there...TC.

Those are odd looking thamnophis. The lateral stripe on this one seems to be on the 2nd, third and fourth rows of scales. The "face" looks very eastern though. Is there some consistancy in the appearance of this form? More pics whould be great.

Joe
http://www.herpnet.net
Reptiles and Amphibians of Iowa and Minnesota

I have never seen anything like this site. Really, almost every snake I pick up is different. That is very unusual. The specific area where I see all the intergradation is about 5 acres. Lots of classic garter habitat and a nice hibernaculum. It's my no fail hot spot - never been skunked yet
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Tim

This snake was found about 25' from the one above. It seems to exhibit mainly T. radix characteristics - thin stripe (3rd and 4th rows), black bordering labial scales, neck is thinner. Once again I would appreciate any comments. There are a lot of interesting individuals in this area, fortunately there are a lot of them on this site

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Tim

I'm no expert on radix. I rarely get to see them, but I would have to agree with you on this one. The stripe on rows 3 and 4 would be butleri or radix, and it doesn't look like butleri.

Also, it doesn't seem to me that butleri and radix should occur together. Have you ever found them both at the same site?

Very interesting pics, Tim. I'm going to have to come over your way and get some pics of snakes in the field. Hope you'd be willing to go out with me if I do. It may have to wait a few weeks though

Later, Terry.

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Tim

This one looks like a perfect radix to me.

Joe