Reptile & Amphibian Forums

Is it possible to determine (or guess) the sex of a rattlesnake visually in the same way as with most adult colubrids, i.e. by examining the taper of the base of the tail? (Uniform taper - probably male; more rapid taper - probably female) Since rattlesnakes tend to be relatively stout, I'm not sure if this works with them.
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MichaelB

Generally, yes it does. But as with colubrids, it's not 100%.
Probing is still the preferred method.
Bill

I agree with what Bill said, but I'd expand on it a little bit, since you didn't specify whether you were speaking in general terms, refering to adult animals, or neonates...

Where adults are concerned, I find it to be extremely easy to visually sex most species of rattlesnake, especially if you just happen to have one of each sex in front of you. If you don't have the luxury of having one-each for comparison, then it still isn't too hard most of the time, again, in adults.

Young rattlesnakes can be a completely different experience... some, like C.atrox are fairly well a no brainer in my book. Others, like C. horridus can be a nightmare (for me at least) to try to visually sex... as Bill said, it then becomes a probe-only effort if you need accuracy.

Perform subcaudal scale counts on sheds is a more effective way that just looking.... the best money is on probing for accurate sexing.... visually sexing can be accurate, but it varies from species to species, as not all female rattlesnakes have tails of significantly shorter length and tapered profile to make the eye-ball method reliable.....

>>Is it possible to determine (or guess) the sex of a rattlesnake visually in the same way as with most adult colubrids, i.e. by examining the taper of the base of the tail? (Uniform taper - probably male; more rapid taper - probably female) Since rattlesnakes tend to be relatively stout, I'm not sure if this works with them.
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>>MichaelB
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"Seek first to understand, then to be understood"

Thanks, Blackwater and Bill, for helping me out. The specific guy/gal in question is a C. atrox juvenile, less than 1 meter (3 feet).

One thing I recall hearing or reading somewhere (probably on one of these forums!) is that the number of rings on the tail *might* help to determine gender on W. Diamondback and/or Mojave rattlers. I'm skeptical myself, but was wondering if there's anything to that.
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MichaelB

(from the snake - not the outbuilding)...so I can count the subcaudals. (He/she shed last week.) I'll let you know what I come up with.
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MichaelB

Apparently the ring thing isn't the best because there's a lot of overlap. I sexed mine both visually and subcaudally and they agreed. I'd probe but I think she'd never forgive me .

.

Check Klauber's rattlesnakes books, and some of his other publications from San Diego Natural History Museum. He has published tons of data on subcaudal counts as it relates to sexing rattlesnakes. In lepidus or willardi a count of 19 would be a female, but there is overlap in the low 20's... I don't know atrox numbers. Good luck.

Thanks for the reply. I don't have that book, so I'll move this back up on the forum and see if someone can tell me if I need to re-name Billy.
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MichaelB

Well, books are what we write about these great beasts that don't read, so if you want to be sure, probe them. Cheers.