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Ratio calculators
Posted: 31/10/2013 by Hayley35

Hi all,

I'm new here and this is my first post.  I was wondering whether anyone could point me in the right direction for the correct ratio calculator for marginated tortoises.  I am looking to hibernate mine 4 year old (sex unknown) by the fridge method on the 1st Dec so will be starting wind down tomorrow.  I am so, so scared because the ratio calculator I used said he was underweight and shouldn't hibernate but the vet (specialist exotics vet) said he was fine to hibernate.  I just wanted to know the correct ratio so I can see for myself.

Thanks in advance from one petrified owner!

Re: Ratio calculators
Posted: 01/11/2013 by Tom

Hello Hayley,
The Ratio can't be used for marginata.
How long have you had it?
Have you kept weekly weight records? If so can you post this year's please?
Hibernation is a natural process & safe if carried out correctly.

Re: Ratio calculators
Posted: 01/11/2013 by Hayley35

Hi Tom

I have learnt so much over the last few months and wasn't aware until recently that I should be weighing him.  I have had him for 16 months and have been weighing him for two months.

Sept - 712g

Oct 723g and 178mm.

I found a ratio for marginated by Hailey at and it said he was underweight.  Is this not the correct calculation?  He was 4 in October.


Many thanks


Re: Ratio calculators
Posted: 01/11/2013 by Tom

Hello Haley,
A. Hailey is a respected author but the papers quoted are over 20 years old. Much of the fieldwork carried out by Hailey et al, took place at Alyki in Greece & involved T. hermanni & T. ibera {then known as T. graeca).
As with the Ratio developed by Oliphant Jackson, it cannot be used for marginata.
Your tort. has gained weight in October & therefore has obviously moved back indoors.
You say that you are "petrified" by the thought of hibernation. In view of that I suggest that you continue feeding until the end of November, then wind down following the method detailed on this site, (reduce the period by 20% if faeces cease to appear when he's placed in water).

Re: Ratio calculators
Posted: 01/11/2013 by Tom

Then hibernate for 8 to 10 weeks. This will give you confidence for next year & you will have a year's dated weight records to refer to as a guide.
Best wishes


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