Hibernating my tortoise- help!

RE: Hibernating my tortoise- help!

Julie Innes — Wed, 09 Jan 2019 16:06:05 GMT

[quote user="Gillian Mostyn"]I agree that the box is best left open - but the fridge really does have to be a good quality one then. I have had 3 tortoises that have been frozen solid in normal domestic fridges. Enclosing them in a couple of boxes won't stop the fridge getting too cold, but it will protect the tortoise from shorter term fluctuations[/quote]

. I'll add that to my list of things to fret about!!

RE: Hibernating my tortoise- help!

Gillian Mostyn — Wed, 09 Jan 2019 15:28:18 GMT

[quote user="Marie Kubiak"]I don't tend to worry about ventilation, as long as the door is opened daily and the fridge isn't damp or contains any organic material. Reptile oxygen demand is so low when hibernating they won't have an issue unless sealed in an airtight box within the fridge. I tend to use open tupperware containers and ensure air flow is free within the fridge.[/quote]

I am not concerned by oxygen levels - they'd probably survive for weeks on the amount in a fridge! But I do have concerns about fungal spores (mildew) in non-moving air. Maybe I'm worrying too much.

I agree that the box is best left open - but the fridge really does have to be a good quality one then. I have had 3 tortoises that have been frozen solid in normal domestic fridges. Enclosing them in a couple of boxes won't stop the fridge getting too cold, but it will protect the tortoise from shorter term fluctuations.

RE: Hibernating my tortoise- help!

Julie Innes — Wed, 09 Jan 2019 15:08:11 GMT

Thank you Marie and Gillian!

I have a max/min thermometer, and it seems to be fairly stable between 4 and 6C.

I checked him at lunchtime and he is not moving, no urination/ defaecation, looks like he is asleep. Will add water as you suggested, Ruth, and I've taken the lid off his box so I can see him better.

He is a lovely little tortoise! His name is Diggle and I am amazed how fond you can get of a tortoise! He is a sassy little guy, and it will be a long few weeks for me, I'm sure! He's a reasonable size, and although I'm saying he is 3, I'm not really sure how old he was when I got him (rescued!) I've had him 2.5 years and I think he was just a baby when he came, as he was pretty small. How long do you think I should let him sleep? (then maybe you can all hold my hand again when it comes time to wake him up!! )

RE: Hibernating my tortoise- help!

Martin Atkinson — Wed, 09 Jan 2019 14:49:57 GMT

[quote user="Marie Kubiak"]

Hibernation is also thought to be important in triggering normal follicular cycles/ovulation and retained follicles with secondary consequences of septic coelomitis are exceptionally common in over-wintered tortoises, especially when kept alone. Being tortoises, they can be filled with rotten yolk and a knackered liver for a long-time without showing clear signs complicating diagnosis and management. I like to scan any female tortoise that comes in.

Obesity/hepatic lipidosis, nutritional secondary hyperparathroidism, shell deformity, dystocia and follicular stasis are all potential consequences. I'm reluctant to avoid hibernation in female tortoises and more comfortable with doing so in males due to the lack of reproductive issues.

[/quote]Interesting. My current nurse with an over-wintering tortoise is not sure what sex it is. She has a flat ventral plastrum and a short tail but is smaller than a 15 year old female Hermann's should be, is aggressive to her male companion and has never laid eggs. We're wondering if there is a non-invasive way of sexing her like by DNA?

RE: Hibernating my tortoise- help!

Miriam Lodewyks — Wed, 09 Jan 2019 12:09:22 GMT

Julie, you've really made me chuckle - I can so relate! Mother hen!

But it sounds like you've done exactly what needed to be done, and as long as you follow Marie Kubiak's advice, you won't go far wrong.

Let us know how it goes when you wake him up in Feb...

RE: Hibernating my tortoise- help!

Marie Kubiak — Wed, 09 Jan 2019 11:35:04 GMT

[quote user="Martin Atkinson"]

I think what you are doing and Ruth has qualified is good but, and maybe one of the exotic experts will come on and explain, I don't know why there is such an obsession with hibernating tortoises. Given a suitable environment i.e. a warm house and tortoise enclosure/table with a suitable UV lamp they can be happily kept awake all year. Two of my nurses have done that and one brought the tortoise in to work each day where it wandered around the surgery trying to shag my shoes every now and again!

[/quote]

Short-term over-wintering at higher temperatures is fine and I use it when I have an animal that is underweight or health is unknown/poor, however long-term it can cause problems. Tortoises grow based on food intake and environmental conditions rather than life stage, so without hibernation they don't get the growth check they have evolved to incorporate into their growth/development. They then grow year round with abundant calorie intake from food of likely poor nutritional value and the increased growth leads to higher body weight/size, early sexual maturity (maturity is size rather than age induced), faster shell growth and greater metabolic pressure in an animal already on a calcium balance knife edge. Hibernation is also thought to be important in triggering normal follicular cycles/ovulation and retained follicles with secondary consequences of septic coelomitis are exceptionally common in over-wintered tortoises, especially when kept alone. Being tortoises, they can be filled with rotten yolk and a knackered liver for a long-time without showing clear signs complicating diagnosis and management. I like to scan any female tortoise that comes in.

[quote user="Julie Innes"]I've peeked in at him a couple of times, and when I do he has moved a little- does this mean he's not asleep?! I keep thinking I hear him scratching in his box, but can't be sure it's not just noises from the fridge! What should I do?? Should I leave him alone and trust that he will sleep, just opening the box now and then to weigh him/ check for any urination/ defaecation, or will he not sleep and die instead[/quote]

Moving legs a little is fairly normal, if he is actually moving round then that implies temperatures are not cool enough - check that his box is staying 4-6C, and that no urine has been passed. You can put him on a bit of paper and draw round him to see if he rotates himself! I rely heavily on weight assessment - there is little else that will quickly and non-invasively tell you whether the tortoise is maintaining an adequate metabolic status for hibernation. I recommend twice weekly weighing for any hibernating tortoise and to wake up if they lose more than 1% per month of hibernation. For a small tortoise I wouldn't hibernate for more than 4wks, and increase by 1wk per year until you reach 10-12weeks which is the maximum length.

I don't tend to worry about ventilation, as long as the door is opened daily and the fridge isn't damp or contains any organic material. Reptile oxygen demand is so low when hibernating they won't have an issue unless sealed in an airtight box within the fridge. I tend to use open tupperware containers and ensure air flow is free within the fridge.

Marie

RE: Hibernating my tortoise- help!

Ruth Gray — Wed, 09 Jan 2019 11:12:44 GMT

I have a max/min thermometer in my hibernation fridge that I check daily (this also means you remember to open the door of course). As well as my gang in their tupperware boxes I also have lots of 2L bottles filled with water as I was told this helps keep the temperature in the fridge more stable? I would be able to keep my tortoises in a suitable environment all year round (and that would probably be easier for me) as I have a reptile shed that is always 20C+ but I was under the impression that it was better for them to have an annual hibernation? I had assumed due to them maybe growing too fast otherwise.

RE: Hibernating my tortoise- help!

Gillian Mostyn — Wed, 09 Jan 2019 10:16:05 GMT

There is no secret to reptile behaviour, including tortoises. If they are warm, well hydrated and healthy they will be strong, move quickly and eat very well. If they aren't, one of those things is 'off'. Therefore, if your tortoise stops eating and 'seeks out cold areas' (not normal behaviour as such) then the most likely reason is that they are struggling to maintain their body temp. In that situation, it is 'safer' for them to wait it out and use as little energy as possible, or when prolonged to get even colder and hibernate (shut down their body systems, not sleep) than try to manage in suboptimal conditions.

As Martin suggests, tortoises can be overwintered indefinitely. However, many species require such high and reliable temps (not UK room temp) that this is a real struggle. In which case it is safer to hibernate than to try to maintain them at lower temps. There is also a belief that tortoises should be able to show natural behaviour, including hibernation, and some species' health suffers if they don't.

As far as hibernation goes, (in the same way as housing) there is no 'one size fits all' method as this isn't the Southern Mediterranean area! We cant just say to pop them in a box outside/in a shed if you live in Scotland, but you probably could in a coastal area of Cornwall! Therefore, the following is a guide:

Temp should be maintained at approx 2 to 10 degrees, ideally around 5 degrees. Most issues I see are due to them being kept too warm. They don't hibernate, but they do starve!

Tortoises are prone to airway disease. Keep the air around them as clean and well ventilated as possible. Use inert materials for boxes and packing materials (Tupperware, polystyrene etc). No shredded paper or straw type stuff...it is very very dusty and if it gets damp will produce fungal spores very quickly. I recommend putting them in a box only slightly bigger than them, then putting that box, packed in polystyrene pieces/beads, inside another box. Lots of air holes, obviously.

If you use a fridge you need to ventilate as often as possible, or ideally fit a small air pump such as those used for aquaria.

Check them daily. If they are hibernating, then you can't 'wake' them unless you warm them.

Personally I recommend limiting it to a max of 12 weeks, less if young. This is arbitrary, but based on what would be 'natural' and allows sufficient summer for them to build up weight!

Use a min/max thermometer inside the box, or ideally a thermometer probe which alarms if it gets to 0 degrees. If the environment warms or cools too much, recover them with a long warm bath and overwinter.

There's probably lots I've left out, but the most important thing is to get the temp and ventilation right.

RE: Hibernating my tortoise- help!

Julie Innes — Wed, 09 Jan 2019 10:00:20 GMT

I think the reason I decided to do it this year was because he seemed to be trying to hibernate, despite heat pads/ lamps, and I was worried he would just stop eating, but not quite hibernate. I didn't do it last year, and by march/ april he started to become very lethargic and it took quite a bit of effort/ bathing/poking at him to keep him up and about. I was worried about him, and thought it was because I hadn't hibernated him!

I constantly worry about being a bad tortoise mum!

RE: Hibernating my tortoise- help!

Martin Atkinson — Wed, 09 Jan 2019 09:06:46 GMT

RE: Hibernating my tortoise- help!

Julie Innes — Wed, 09 Jan 2019 08:27:10 GMT

Thank you, Ruth! Yes, that sounds like pretty much what I have done, apart from the container- maybe a Tupperware box would be a better idea. I'm just a bit paranoid about the whole thing- like I say, it just feels all wrong, but I'm sure it'll be better for him in the long run! I'll be glad when it's over- I miss him already!

RE: Hibernating my tortoise- help!

Ruth Gray — Tue, 08 Jan 2019 22:55:23 GMT

I hibernate my Hermann's tortoises every year following a protocol given to me by a nurse with exotic qualifications. I can email them to you if you like? My protocol includes bathing during the starvation/reduction in light/heat phase to help hydrate them and encourage them to empty their bowels. Once they are in the fridge I open the door daily, check the temperature of the fridge and check for the tortoises for evidence of them having passed anything. I have them in individual suitably sized tupperware containers with no lids so I can see them and their container easily. If they have passed anything then I wake them up. I am not so good with the weighing regularly once they are asleep but I do record a baseline weight when I put them in the fridge in case I need it. I'm just not sure if the protocol for your Horsefield will be the same as for mine?