Maximum safe weight loss during hibernation (Hermanns)

[Dave CH]

Good morning everyone,
I'd like your expert advice on maximum (percentage of pre-hibernation body weight) in-hibernation weight loss for Hermanns.

We're hibernating four tortoises, a pair aged between 75 and 90, a pair aged around 7.

The older pair, R + S, are 121 days into hibernation and have lost 9.92% and 4.0% respectively.
In theory they would not be waking up for another 60 days or so.

The younger pair, P + F, are 66 days into hibernation and have lost 9.07% and 8.33% respectively.
The current target date for bringing them out is in another 38 days.

In other winters (the ones where I've weighed the torts) it has not been unusual for in-hibernation weight loss to hover around 9% to 10%.

All advice is welcome (particularly as Tort Vet is currently on vacation).

Best regards (from chilly Switzerland) -
Dave

 

[Tom]

Good morning everyone,
I'd like your expert advice on maximum (percentage of pre-hibernation body weight) in-hibernation weight loss for Hermanns.

We're hibernating four tortoises, a pair aged between 75 and 90, a pair aged around 7.

The older pair, R + S, are 121 days into hibernation and have lost 9.92% and 4.0% respectively.
In theory they would not be waking up for another 60 days or so.

The younger pair, P + F, are 66 days into hibernation and have lost 9.07% and 8.33% respectively.
The current target date for bringing them out is in another 38 days.

In other winters (the ones where I've weighed the torts) it has not been unusual for in-hibernation weight loss to hover around 9% to 10%.

All advice is welcome (particularly as Tort Vet is currently on vacation).

Best regards (from chilly Switzerland) -
Dave

What is the temperature in the hibernacula?
What substrate did you use and is it damp?

 

[Dave CH]

What is the temperature in the hibernacula?
What substrate did you use and is it damp?

What is the temperature in the hibernacula?
What substrate did you use and is it damp?

Hello Tom,
Thanks for getting back to me.

R+S are boxed in one of the cellars at 46 to 52 F.
This is cold as we get get without putting them outside, where it's regularly 14 F.

P+F are in a fridge at a stable 44 F to 48 F.

We used dry, peat-free, fertilizer-free, perlite-free soil over sand and grit, topped off with a thick layer of nut leaves.

Neither area is damp.

None of the four torts have dug in (and never do).

R+S spent almost all of their lives self-hibernating outside.
I'm aware of winters at - 4 F, in which the daytime temperature didn't rise above 14 F for weeks at a time.
But there's too much fauna around to allow them to do that here.

Dave

 

[Tom]

Hello Tom,
Thanks for getting back to me.

R+S are boxed in one of the cellars at 46 to 52 F.
This is cold as we get get without putting them outside, where it's regularly 14 F.

P+F are in a fridge at a stable 44 F to 48 F.

We used dry, peat-free, fertilizer-free, perlite-free soil over sand and grit, topped off with a thick layer of nut leaves.

Neither area is damp.

None of the four torts have dug in (and never do).

R+S spent almost all of their lives self-hibernating outside.
I'm aware of winters at - 4 F, in which the daytime temperature didn't rise above 14 F for weeks at a time.
But there's too much fauna around to allow them to do that here.

Dave

I don't usually weigh mine or disturb them in any way during brumation, so I can't answer your question of how much weight loss is too much. When going by feel, I have not noticed much weight loss at all, if any. I suspect your temperatures may be a bit too warm. I've had horsfield tortoises get active and moving around at 39F (4C), while other species like Chersina or Gopherus seem quite content at 45-50 (7-10C). I've always done eastern hermanni around 40-45F(4-5C) and experienced no problems at those temps.

I would not recommend soil. I don't know how it works in Switzerland, but over here that soil is made from people's composted yard waste. It could be toxic plants, or yard grass that has been sprayed with all those toxic lawn chemicals sold at hardware stores. Soil manufacturers also add in all sorts of weird stuff to get their product to the right consistency. They do not intend for small animals to be living in or on it in closed containers. I don't know if that is related to your issue or not, but it seems sensible to be that if there is something irritating in that soil, it would make them restless and too active. I prefer to use more inert materials like coco coir, orchid bark, or cypress mulch.

 

[Dave CH]

I don't usually weigh mine or disturb them in any way during brumation, so I can't answer your question of how much weight loss is too much. When going by feel, I have not noticed much weight loss at all, if any. I suspect your temperatures may be a bit too warm. I've had horsfield tortoises get active and moving around at 39F (4C), while other species like Chersina or Gopherus seem quite content at 45-50 (7-10C). I've always done eastern hermanni around 40-45F(4-5C) and experienced no problems at those temps.

I would not recommend soil. I don't know how it works in Switzerland, but over here that soil is made from people's composted yard waste. It could be toxic plants, or yard grass that has been sprayed with all those toxic lawn chemicals sold at hardware stores. Soil manufacturers also add in all sorts of weird stuff to get their product to the right consistency. They do not intend for small animals to be living in or on it in closed containers. I don't know if that is related to your issue or not, but it seems sensible to be that if there is something irritating in that soil, it would make them restless and too active. I prefer to use more inert materials like coco coir, orchid bark, or cypress mulch.

Thanks Tom,
The indoor terrariums for the youngsters are orchid bark. I'll plan that for next year's hibernation for all four.

To be honest, I'm asking the question (re weight loss) as I've read in a number of (seemingly reliable) places that 10 percent is the maximum.

And, of course, I'm "responsible" for the guys being OK. So I worry...

Dave

 

[Tom]

Thanks Tom,
The indoor terrariums for the youngsters are orchid bark. I'll plan that for next year's hibernation for all four.

To be honest, I'm asking the question (re weight loss) as I've read in a number of (seemingly reliable) places that 10 percent is the maximum.

And, of course, I'm "responsible" for the guys being OK. So I worry...

Dave

Have you offered them a drink? I know some people do that, though I never have.

 

[Dave CH]

Have you offered them a drink? I know some people do that, though I never have.

Nope.

Actually, this is the first time I've weighed them since they went down. I normally do that a little more regularly.

F. (a 7-year-old) is all tucked in (head, legs, and tail).