Growth Rings - How Old is Ari?

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Aristotle

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Here I go AGAIN! Sorry, I have question after question for all of you. I DO lots of research before I post on TF, and seek help only when I can't apply the knowledge I gain to Ari (with reasonable confidence).

I read some of the growth ring threads on TF and did some outside research, but I am having problems determining what is a growth ring on Ari's shell vs. what may be "boundaries" of growth rings. I don't know if that makes sense to any of you. The reason I raise this is because I was told by the exotic animal store where I bought her that she was 6 months old (this was about 2 months ago), and it looks to me that Ari has multiple growth rings, suggesting that she is at least 1-year-old or more. Below is the best quality close-up photo of Ari I could get at the moment. If anyone can interpret the growth rings and come up with an estimate of Ari's age, I would really appreciate it.

There's a little bit of dirt on her shell, as she had just come up for a meal after burying herself for a while when I took the picture.

1growthrings.jpg


Best,
Kristina
 

Yvonne G

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Hi Kristina:

You can't count growth rings on tortoises like you do with trees. Tortoises might have growth spurts...times when food was more than plentiful...and they'll show more than one growth ring in a year's time. And then, in times of not too much food, no growth shows at all in the space between the scutes.

I'm sure that the folks more experienced with the Mediterranean tortoises can give you an idea of Ari's age if you tell his size, weight and maybe show a picture with something next to him for size comparison.
 

Michael Bird

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Just as an example, without going into too much detail, I got my female Jordanian Greek almost exactly one year ago. The previous owner didn't even know that she was a tortoise (he thought she was a male box turtle) and she was kept in a fairly small glass aquarium with newspaper as substrate, a simple UVA heat lamp, and fed almost exclusively iceberg lettuce. He also didn't have any idea how old she was because he had only recently acquired her from another family and they told him that she was a box turtle and told him to care for her the way he was doing it.

When I got her, Gracie's shell was about 5 1/2 inches long. In the 12 months that I have had her, feeding her properly, using a UVB lamp, coconut coir substrate, and in a larger (although still not large enough) wooden bookshelf box, she has had six separate growth spurts that I know of, adding at least six new rings to her scutes. It could be as many as eight new rings, depending on how you count them - I just know of six growths for certain. And she's up to 6 1/4 inches of shell now.

So, as emysemys said, you really can't even begin to guess at their age by counting the rings. All it can tell you is how many times they have had significant growth...
 

Aristotle

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Michael Bird said:
Just as an example, without going into too much detail, I got my female Jordanian Greek almost exactly one year ago. The previous owner didn't even know that she was a tortoise (he thought she was a male box turtle) and she was kept in a fairly small glass aquarium with newspaper as substrate, a simple UVA heat lamp, and fed almost exclusively iceberg lettuce. He also didn't have any idea how old she was because he had only recently acquired her from another family and they told him that she was a box turtle and told him to care for her the way he was doing it.

When I got her, Gracie's shell was about 5 1/2 inches long. In the 12 months that I have had her, feeding her properly, using a UVB lamp, coconut coir substrate, and in a larger (although still not large enough) wooden bookshelf box, she has had six separate growth spurts that I know of, adding at least six new rings to her scutes. It could be as many as eight new rings, depending on how you count them - I just know of six growths for certain. And she's up to 6 1/4 inches of shell now.

So, as emysemys said, you really can't even begin to guess at their age by counting the rings. All it can tell you is how many times they have had significant growth...

Thanks Michael. Your experience with Gracie is very helpful - thanks for sharing. Can you post a picture of her? I'd love to see what she looks like. She sounds like she is a happy, healthy, well-cared-for tort!

Best,
Kristina
 

Tccarolina

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I agree with Yvonne and Michael. I see three periods of growth. If your tortoise was wild-caught (unlikely, considering her size), it appears she would be going into her fourth year of growth, assuming she did not grow her hatch year, as the rings are pretty consistent in size, and there are no small or blended rings.
If she is captive-bred, then she was well fed three distinct periods, with a pause in between.
 

Aristotle

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supremelysteve said:
I agree with Yvonne and Michael. I see three periods of growth. If your tortoise was wild-caught (unlikely, considering her size), it appears she would be going into her fourth year of growth, assuming she did not grow her hatch year, as the rings are pretty consistent in size, and there are no small or blended rings.
If she is captive-bred, then she was well fed three distinct periods, with a pause in between.

THANK YOU Steve! That is very helpful. One more request of all you experts: Below is a cropped portion of the photo, in which I have labeled what I think/I guessed are the 3 rings and period of less feeding referred to by Steve. I just realized that the "Period of less feeding" bubble should be moved a bit to the left with the point in the light area between the first 2 growth rings. Sorry but I don't have time right now to re-label the photo - hopefully this makes sense to you. If not, later I will post a corrected better photo.

I would appreciate feedback in terms of my accuracy. Thanks.

Best,
Kristina

1growthrings-3.jpg
 

Tccarolina

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Kristina,
Growth ring 1 is correct (in my opinion), but 2 and 3 are both outside ring 1. Your other labeled rings are just color bands within the first layer of growth. The whole growth layer is the growth ring. Where the physical layer stops and the next layer begins is the period of non-growth. The growth periods are smooth ridges, and the non-growth periods are are the cracks (not really cracks) between the ridges. You typically need to observe multiple scutes to clearly identify growth periods. Looking at you first picture there are three periods of outward growth. Each of these would be a growth ring. With in these smaller patterns are visible, depending on food, temperature, hydration, and humidity during the growth period. In tortoises that hibernate the rings are more clearly defined since the inactive period is long. In captive bred tortoises, especially those raised indoors, you have new distinct layers made frequently, or never, depending in part on how often, frequently, and consistently the tortoise is fed.
1growthrings1.jpg
 

Aristotle

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Thank you Steve. You have really educated me on this topic. For some reason that I can't begin to explain I thought I should count growth rings from the outside in on each scute. I appreciate your kind manner of setting me straight.
I feel like I am doing everything wrong, including the set-up of my enclosure, so I'm starting from scratch and trying to prepare a comprehensive plan to better arrange my enclosure.

Thanks to everyone for helping with guess-timating Ari's age.

Best,
Kristina
 
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