Hibernation Fridge?

[Emma25]

Hello Everybody, Nina!

I am looking for a bit of advice please. Although I don't feel like there has been much of a summer (particularly in the North where we are) we already thinking ahead to hibernation and this year we really want it to work for Penny. We are thinking that the fridge method will prove far more successful as we can maintain an ideal temperature.

For people who use this method what fridge do you use, does anybody have any recommendations or pictures? Penny is a Horsfield incase that makes any difference.

We've had Penny over a year now and despite a few anxious couple of months at the beginning when we first got her she is doing really well. She is a good eater, rose petals and clover are her current favourites and she loves exploring. We try to put her out most days, unless its really wet and bring her in on an evening. She usually sulks when she comes in.

I've hopefully attached some pictures of Penny's new extension to her outside enclosure that we built earlier this year, and a couple of pictures of her enjoying it.

Thank you
Emma

[Nina]

Hi Emma,

It's great to hear from you, and I hope that lots of people look at this post because you've created a brilliant outdoor enclosure for Penny! So much interest and variety and such a good size too. Penny looks like she is really enjoying it.

Regarding hibernation -- lots of people just use an ordinary under the counter fridge. The important thing is that it doesn't have a little freezing unit in it -- so a larder fridge. I use an under the counter fridge, but I also have another fridge that I use when mine are hibernating. Lots of people use the good quality drinks fridges like ones made by Husky. Here are what they look like, but you can get them cheaper than on this site: https://www.currys.co.uk/deals-on-compu ... ws-laptops (and of course it means that when your tortoise isn't hibernating you have a nice little drinks fridge. Obviously if you have one with a glass front you just need to tape some cardboard over the front to keep out the light. Some people have found that some drinks fridges don't keep a consistent temperature, but normal fridges fluctuate a lot as well, and a lot of people use these drinks fridges successfully.

You will need one of the digital fridge/freezer thermometers like this: https://www.pharmacy-equipment.co.uk/pr ... er-tmm105/ but I think you already have one. The Max/Min facility is really useful, so you can see how warm or how cold it got since you last looked.

Do you need the instructions on winding down, fridge hibernating and waking from hibernation (I can't remember if I sent them to you already).

It's an exciting (and scary) time thinking about hibernation, so ask all the questions you want. I try to hibernate mine as late as practical (usually December), so that when they wake up it isn't too long until warmer weather is on the way and weeds are growing. I think for Penny, as she is something like 8 years old now and a very good weight, you could aim for at least 10 weeks, but not more than about 12 or 13 weeks.

Horsfields are super good hibernators although they can take a long time to settle (as you know from last year, it can be a bit unnerving when you hear them scratching around for a week or two after you put them in the fridge), and they can take lower temperatures than some other species, so if the fridge temp does drop down to 1C or 2C for a bit then that is fine, but you want to aim for a temperature of around 5C.

Thanks again for the photos -- I think your enclosure is lovely!

Nina

[Emma25]

Hello Nina, thank you so much for the quick reply.

She really does love her outdoor enclosure, and she is one spoilt tortoise lol

We last weighed her on August 10th and she was 1371g, which is bigger than she was when she went into hibernation last year. She's roughly 8ish we think as that's what the vet thought in her check up.

She gets so frustrated when she doesn't get outside that we really don't want her to go through that this year again. I think we did start the hibernation wind down too early last year (October) so the plan is to wind her down over November and a December hibernation. It is nerve wracking but we know it's what is best and what she needs.

Thank you so much for the link and the information, and we do have a variety of thermometers from last year!

If you could forward any information onto me that would be great thank you, I think you have my email address as I emailed you some pictures earlier this year but if not just let me know and I can email you again.

Many thanks again,
Emma

[Nina]

Hi Emma,

I've emailed you instructions for winding down, fridge hibernation and waking up from hibernation, plus an example of the sheet that I use to monitor and record stuff during winding down and hibernation.

I am curious though about Penny's age, as she is much heavier than I would expect an 8 year old tortoise to be. My Doris has always been small for the species and she is currently 20 years old and weighs 700g. Dolly, who is on the big side, is 14 and weighs 945g.

Tortoises are like people, and some are naturally larger than others, but Penny is a whopper for a Horsfield if she is only 8 years old. I just wonder if she might be a bit older than you thought. What is her length (SCL)? Length has to be measured in a certain way, and here's our guide on how to do it: https://www.thetortoisetable.org.uk/tor ... measuring/

Lol, if she keeps growing we might have a Guinness Book of Records entry!

Nina

[Emma25]

Hello Nina,

Thanks for sending that through, it's really good to see your pre-hibernation countdown plan.

I've measured her tonight, she wasn't particularly co-operative so you might have to give or take a mm but she is 7inches in length. Last weight on August 10th was 1371g. Vet did say it was very difficult to call her age so that was a rough guestimate and her previous owners didn't know either.

She weighed 1237g on hibernation day last year and has steadily increased throughout the year, although generally fluctuating around what she is now.

Hope this helps

Thanks
Emma

[Nina]

Hi Emma,

Well, I think that Penny is just a big girl. I measured my larger Horsfield (Dolly). She is just under 7" (about 6.75") and weighs 945g, but she has put on way too much weight this year, so I need to monitor her weight gain more closely, as it is really important that tortoises grow slowly so that they don't get deformed shells.

I think Penny is fine, but I would definitely monitor her growth and try to ensure that she doesn't gain, on average, more than 1g - 3g per month (just a rough guide, and some months she will grow more and some less, but it's something to go by).

Nina

[Emma25]

Hi Nina

Thank you, we will keep an eye on. We didn't realise she was such a whopper

[Kazcp1]

Hi, I'm currently reading more about hibernation so came across your post! My tortoise we believe is nearly 4, I took him to the vets last week for a check and he advised me that he should be hibernated every year and he's never been before. He has advised me to start a controlled hibernation from today as follows -
2 weeks in his table, no food but water still
Then 2 weeks no food and no light but water bowl still
Then 2 weeks in a colder room
Then 4 weeks in the fridge, in a ventilated see through plastic box with hay on top of him (so i can see if any urine etc) with weekly checks, if all ok then carry in for 2 more weeks and then do the above in reverse to bring him out of hibernation.
How does this all sound? I'm so nervous

[Nina]

Hi Kazcp1 and welcome to The Tortoise Table.

Hibernation is always a bit of a scary time, but we'll help you through it, and can send you lots of information.

First of all can you confirm what species your tortoise is, and how much he weighs?

Your vet's instructions are OK, but slightly different to the standard advice that most of us follow, especially on the waking from hibernation part, but also the way you reduce the number of hours of heat and light. The vet is right that you must withhold food from the tortoise for a certain period before hibernating, as a tortoise has to go into hibernation with an empty stomach but a full bladder (and if he wees in hibernation then you must wake him up so that he doesn't dehydrate). The amount of time you withhold food depends on his weight and age, so do let us know what those are.

The fridge you use must not have an ice compartment, and you should open the door every day for a few seconds to allow for an exchange of air (you can miss the odd day, but every day is best). You will want to keep a record of his weight throughout the whole process -- at the start of wind down (which is what the preparation period is called), the day he goes into the fridge, and every three weeks or so while he is in the fridge. If he loses more than 8% - 10% of his body weight in the fridge then that is another reason to wake him up. If he is doing well in the fridge then you ought to be able to leave him in there for about 8 weeks for a first hibernation.

I have attached information sheets on preparing for hibernation, the hibernation itself, and waking from hibernation (there is no need to do the long process that your vet described in reverse -- you can just take him out of the fridge, put him in his tortoise table at the cool end, and let him walk towards the light at the warmer end to warm up and he will be fine. And then give him a nice long soak in warm water to get rehydrated. Have a read of the instructions and get back to us. You will see that in the winding down instructions they talk of four weeks with no food, etc. -- this is for an adult tortoise, and if your tortoise is not an adult the fasting time will be anywhere from two to four weeks, depending on the weight. So, for example, if your tortoise weighs 500g, you will probably want to withhold food for three weeks, and you can still use the four week model for reducing light and heat, but your four 'weeks' will be five days each instead of seven. Sorry if this sounds complicated -- it isn't actually, and if you would like to chat on the phone about it some time I'd be happy to do that, at your convenience.

Here are links to the instructions:
Winding down/Preparation: https://www.tortoise-protection-group.o ... cedure.pdf
Fridge Hibernation: https://www.tortoise-protection-group.o ... Sept16.pdf
Waking up: https://www.tortoise-protection-group.o ... 080608.pdf

In addition to the fridge and box (we use shredded newspaper instead of hay, because if hay gets damp it can go mouldy), you will want a thermometer that will tell you at any time what the temperature is in the fridge. The best are digital fridge/freezer thermometers where you sit the display on top of the fridge and then the probe on the end of the long wire goes into the fridge where the tortoise is. Here is what I mean (you can get them in lots of places, but do try and get one with a Max/Min function on it, so that you can see how warm or how cold it got in the fridge since you last looked.
https://www.pharmacy-equipment.co.uk/pr ... er-tmm105/

And remember that the later you put him into hibernation the later he will wake up, and that means there might be more plants available outdoors for him to eat when he wakes.

Sorry this is so long!

Nina


Kazcp1 wrote:
> Hi, I'm currently reading more about hibernation so came across your post!
> My tortoise we believe is nearly 4, I took him to the vets last week for a
> check and he advised me that he should be hibernated every year and he's
> never been before. He has advised me to start a controlled hibernation from
> today as follows -
> 2 weeks in his table, no food but water still
> Then 2 weeks no food and no light but water bowl still
> Then 2 weeks in a colder room
> Then 4 weeks in the fridge, in a ventilated see through plastic box with
> hay on top of him (so i can see if any urine etc) with weekly checks, if
> all ok then carry in for 2 more weeks and then do the above in reverse to
> bring him out of hibernation.
> How does this all sound? I'm so nervous

[Kazcp1]

Thanks Nina, I'm studying all the info now. I'm sure when we got him they said he was 18 months old in may 2021. I weighed him 22 /5/21 and he weighed 204g, I'm sure back then you said he was big. I've weighed him this morning and he is 879g. The vet said he was big too! Maybe he is older or am I feeder!?
Thanks for all the advice.
Emma, I hope Penny hibernates well, I love her enclosure.

[Nina]

Hi Karen,

Ahh, of course I remember you and the handsome Rocky now. You gave him a lovely home, changed substrate and his diet and he was one happy little tortoise. It is a very big weight gain in just over two years though. If he weighed 204g in 2021, I would expect him to weigh no more than about 320 or a bit more now. What you are aiming for is an average weight gain of between 1g - 3g or 4g per month. and it's been about 30 months since then, so I would have expected him to put on about 120 g. Having said that, you are right in thinking that some tortoises are bigger than others. I have one Horsfield who is 14years old and weighs 920g and another who is 20 years old and weighs 692g. But Rocky's is a very big weight gain in just over two years. Having said all of that, one of mine is super greedy -- especially outdoors, and she often gains way more than the average in a month, so I am as guilty as anyone with feeding too much. They say that an image of a single layer of leaves, flowers, etc. that would be enough to make a little jacket or blanket to cover their shell is a good image, or as much as they can eat in 15 minutes, once a day is enough, but recording weight is the best way to keep track.

The thing about Horsfields is that you do have to monitor their food intake. The reason for this is that in the wild they live in areas where there are long cold winters when they hibernate and long hot summers when they aestivate (which is when they sleep because it is too hot for them), and for part of that time it is so hot that most of the food sources have dried up), and it's estimated that they are only awake for around 2 months or so a year. Because of that they are sort of programmed to 'eat for England'. In captivity with us, they are presented with lovely meals every day and still have that instinct to eat as much as possible. This can result in them growing too quickly and developing deformed shells (pyramiding), and other problems.

So I would weigh Rocky every couple of weeks or every month and if he is always gaining more than 1g - 4g per month on average (some months he will gain more and some less) then I would definitely cut down on his food. Also, of course if he is hibernating then he isn't eating and not gaining weight! Would you like one of our Tortoise Observation Records booklets so that you can keep good records for him? Just email me your address and I'll pop one in the post to you: nina@thetortoisetable.org.uk

Nina