Facilitation and Accommodation of True, Seasonal Estivation of Large Sulcatas in a Barn?

[Jeffrey Jeffries]

Hello!

I have seen great pics of winter habitats here but they range in intents and purposes and capacities -- from different regions and climates to different purposes (some keep the animal from estivating at all) and so I asked some specific questions precisely relevant to our intentions (provided our intentions are not somehow misguided).

Quick Background
My wife and I have always given our pets a forever home and do not want to break that for our long-lived buddies.
We have one 9-inch sulcata "Paul" (or Paulina) with gender TBA, but ...
...we also have a male "Bonsai" that is about 100 pounds.

We live in balmy Florida, so winters have been minimal.
The wee one comes inside when temps occasionally drop into or below 40's F, and the huge male has a stable burrow with tree roots and soil, so I put a direct-contact-protected thermostat-equipped heater at the entrance on those odd colds nights, and I insulate the entrance area a bit to keep some heat in and/or freezing air from pouring in.

They've been thriving and growing for years, and the big (rescued) one's newer skute areas and even, overall shell shape has been growing out more nicely under our care.

We'd like to move one day, though, where the heat does not aggravate my own thermoregulatory health issue.

It would not be economically practical to have a year-round, overly-heated outdoor winter habitat that effectively became an indoor petting zoo, merely forcing warm temps and always stimulating the animals to be fully active, feeding and roaming all winter.
I'd like to learn to keep them at low enough temps so they'd estivate and be relatively inactive and mostly fasting in a somewhat natural fashion in winter months (but keeping them from the fatal cold extremes).
I'm happy to build them a solid, insulated, little barn for this.

Moving to Where it Snows a Bit etc.

Pros:
I'm experienced in general animal husbandry including robust but economical habitat construction with carpentry, electricity, etc..
I'm confident I could provide an animal with what it needs in terms of monitored and controlled temps, humidity, and other basics, even in a snowy climate.

I already know all sorts of helpful things like how to keep a tortoise from coming into direct contact with reliable heat sources etc.
It's specific things that I find it hard to put my finger upon.
Basic care and all-around tips are not an issue, but data on professional-class facilitation and accommodation of true, seasonal estivation for sulcatas housed outdoors through hard winters is relatively challenging to find.

Cons:
The main problem is that I have no experience truly getting a sulcata to genuinely estivate for any substantial period in longer-lasting, colder temps.
I do not know if they 1) need some light like a vita-light when getting them to truly estivate for months (?)
I do not know 2) what temps at which to keep them for genuine, seasonal estivation; once I know, I can install a thermostat and monitor and maintain appropriate temp(s) or even regimens.
I do not know 3) if it's best they stay, static that way for months, or if I should bring them out of deeper dormancy it at times by temporarily increasing the heat, light, and food availability, or if that's neither necessary nor recommended by best keepers.

We really appreciate the advice.

Thank you!
Blessings --
Jeff, Tina, Bonsai, & Paul/Paulina(?)

 

[Markw84]

First of all it seems you are confusing aestivation with brumation.

Aestivation is a period of inactivity due to extreme heat, dry conditions and the absence of any substantial foods. Temperatures remain high and continue to support gut microbiome and metabolic activity, but the tortoise has the ability to shut things down with the lack of food. For example, the giant tortoises can go up to a year with no food it they have to. However, they still need to remain warm enough for proper metabolic funtion. Sulcatas can, and do Aestivate, but it is of necessity when food is scarce and temperatures are extremely warm. They simply stay in their burrows where it is 85°-90° and very humid during those times. It is hard on them, but they have evolved way to survive many of those times. Sometimes it kills them.

Brumation is a period of inactivity due to extreme cold. Too cold to support metabolic activity and also too cold to support many of the necessary organisms that make up the gut microbiome of the tortoise. Tortoises from temperate regions where even a burrow will fall below 70° have evolved ways to brumate. Sulcatas cannot to this. A temperate tortoise will fast and stop feeding to ensure the gut is empty. The cold will destroy much of the microbiome and the cold is too low to support metabolic activity. Any food in the gut would rot and poison the tortoise causing enteritis. This is a big killer of sulcatas. People do not understand and feel they are fine in a burrow, even though the temperatures in N America are way too cold to properly support a sulcata through the colder season. They are survivors and many make it through. But sooner or later it will most likely kill them. So sulcatas and all tropical species of tortoises do not have the "programming" to empty their gut and shut down in cool weather. Their gut flora is very temperature dependent as well and temps dropping below 70° starts killing off some of the vital microbes they need for digestion and metabolism. They need to heat to 85° every day. They can survive nighttime temps that dip to 70° or so, but it is not good for them. The come from areas where ground temperatures never drop below 80° in their winter times and the cooler nights of winter are followed by daytime temps quickly warming to the high 80s at a minimum with bright sun. Their winter is dry with no rains and clear skies. The climate of any place in the US is not at all like what they are adapted to.

A sulcata needs a way to heat its core body temperature to over 85° every day. A sulcata should not be allowed to have its core body temperature drop much below 80° at any time overnight. Because of this - moving to a colder climate is a challenge if you want to keep a sulcata.

 

[Tom]

Hello!

I have seen great pics of winter habitats here but they range in intents and purposes and capacities -- from different regions and climates to different purposes (some keep the animal from estivating at all) and so I asked some specific questions precisely relevant to our intentions (provided our intentions are not somehow misguided).

Quick Background
My wife and I have always given our pets a forever home and do not want to break that for our long-lived buddies.
We have one 9-inch sulcata "Paul" (or Paulina) with gender TBA, but ...
...we also have a male "Bonsai" that is about 100 pounds.

We live in balmy Florida, so winters have been minimal.
The wee one comes inside when temps occasionally drop into or below 40's F, and the huge male has a stable burrow with tree roots and soil, so I put a direct-contact-protected thermostat-equipped heater at the entrance on those odd colds nights, and I insulate the entrance area a bit to keep some heat in and/or freezing air from pouring in.

They've been thriving and growing for years, and the big (rescued) one's newer skute areas and even, overall shell shape has been growing out more nicely under our care.

We'd like to move one day, though, where the heat does not aggravate my own thermoregulatory health issue.

It would not be economically practical to have a year-round, overly-heated outdoor winter habitat that effectively became an indoor petting zoo, merely forcing warm temps and always stimulating the animals to be fully active, feeding and roaming all winter.
I'd like to learn to keep them at low enough temps so they'd estivate and be relatively inactive and mostly fasting in a somewhat natural fashion in winter months (but keeping them from the fatal cold extremes).
I'm happy to build them a solid, insulated, little barn for this.

Moving to Where it Snows a Bit etc.

Pros:
I'm experienced in general animal husbandry including robust but economical habitat construction with carpentry, electricity, etc..
I'm confident I could provide an animal with what it needs in terms of monitored and controlled temps, humidity, and other basics, even in a snowy climate.

I already know all sorts of helpful things like how to keep a tortoise from coming into direct contact with reliable heat sources etc.
It's specific things that I find it hard to put my finger upon.
Basic care and all-around tips are not an issue, but data on professional-class facilitation and accommodation of true, seasonal estivation for sulcatas housed outdoors through hard winters is relatively challenging to find.

Cons:
The main problem is that I have no experience truly getting a sulcata to genuinely estivate for any substantial period in longer-lasting, colder temps.
I do not know if they 1) need some light like a vita-light when getting them to truly estivate for months (?)
I do not know 2) what temps at which to keep them for genuine, seasonal estivation; once I know, I can install a thermostat and monitor and maintain appropriate temp(s) or even regimens.
I do not know 3) if it's best they stay, static that way for months, or if I should bring them out of deeper dormancy it at times by temporarily increasing the heat, light, and food availability, or if that's neither necessary nor recommended by best keepers.

We really appreciate the advice.

Thank you!
Blessings --
Jeff, Tina, Bonsai, & Paul/Paulina(?)

I agree with everything Mark said and would add that your current burrow is much too cold, even with heat at the surface. No tropical species of tortoise should be in a burrow during a North American winter. We are regularly in the 70s all winter long in my area with warm spells into the high 80s or low 90s Dec-Feb. All of my sulcatas have burrows for summer when daily highs are always around 100, and the rest of the year they sleep in heated night boxes. Like these:

Single Tortoise Night Box

I like my larger tortoises to live outside full time. My climate permits this year round with a little help. For people who live where it snows all winter, this type of box is still good for warmer weather, getting them out earlier in Spring, and keeping them out a bit later into fall. You'll...

tortoiseforum.org

Double Door Night Box

As the years have gone by and I build more of these boxes, I learn more and more each time. This one is the latest and I incorporated everything I've learned over the years. I also tried to take lots of pics so I can explain in more detail some of what is going on. It will take multiple posts to...

tortoiseforum.org

In summer their boxes are unplugged. In spring and fall, their thermostats are set to 80 when we have warm sunny days most of the time. In winter, their thermostats are set to 86.

Sulcatas do not hibernate. They must be kept warm all year. They also need large warm areas to roam, so small heated areas in snowy climates are not a good way to go either. There is no time of year when they should be cold, inactive and not eating. You are thinking of temperate species like greeks, hermanni, Russians, or our North American Gopherus species. Many sulcatas die annually because all of this is commonly misunderstood.

Years ago, before I figured out how to correctly house and heat them, my sulcatas would get too cold in winter. They did slow down and eat less. Luckily they survived, but man what a difference I saw in their health, vigor and appetites when I started housing them correctly.

 

[wellington]

Mark and Tom are two of the long time experienced members. Listen to them for the health of your tortoises.
Housing tortoises like a sulcata or like what I have leopards, which need the same care, in the winter, in the snowy colder areas is not as hard as one might think. It's more costly then in florida.
A proper sized insulated shed with a hide built inside it heated to 80 is good for night time sleeping. Then the rest of the shed can be heated to a cooler temp for the night until day time, then the whole shed should be 80 with a backing spot of 95.
Portable oil filled radiant heaters, thermostats and timers can do this all for you.
Once it is all correctly set up it's a breeze.

 

[Maggie3fan]

Because it's not good for Sulcata to brumate, this is how I keep Sulcata in the PacificNorthWest
a 20'x12' heated and insulated shed. No matter how cold it is outside, the ambient temp in the shed never drops below 80 degrees. There is room for them to pace inside. Mary Knobbins is a rescued very damaged Sulcata. I see our experts have already responded to your initial post, so I won't repeat it. Please stay for the life of those tortoises.
Tort shed

This is Mary

just because I have chosen these particular photos, does not in any mean Mary, who is only 20 lbs has the option to go in or out. She is small and will lose body heat quicker.

 

[Jeffrey Jeffries]

Thanks much --

2 things:

1)
I appreciate the help and will follow your advice when we move to the cold. This is why I research before I act, always.
I accidentally used the term estivate to describe brumate because it has not been relevant in our lives in this warm climate and I'd crossed the terms, thank you.

It never mattered until we wanted to move because they are, daily, warm and active.
I know know we should not take the approach and will just keep them warm throughout winters including when we move to the cold.

2)
I do want to say when it comes to what I have been doing now and for years, I'm dubious it's been harmful -- I believe that's a misunderstanding due to my description, perhaps making outside ambient temperature look like ones I was exposing the tortoise to (sorry).
I do not let the burrow drop to temps detrimental to the tortoises esp. for the length of time it does. The ground here is very warm with daily thermal inertia as such and it's measured with a a probe frequently.
The remote temperature probe never reports below 65 or maybe 62 or so *very briefly* during the coldest hour of the morning (in the 70's for the majority), and then --
they bask later on, in the daytime, with their shells in the hot sun, warm to the touch for hours... in the 100's to the touch for hours. They thrive this way.

Generations of sulcata tortoises in Florida above the frost line have demonstrated, in our community, they are equipped to get a little cooler breifly at night and warmer in the sun during the day, averaging them well into your described 24/7 temps and never very extreme.

Sorry if I painted a picture of them cold in their burrows for months.
The average temperature of the tortoise taken throughout the day would be the same as the 24/7 temps in your enclosures, at least, because, even in the coldest days, they are basking in the sun with the shell warm to the touch of a 98.6F human, so well above that. Then it takes all night for the back of the burrow to reach 62 coldest for an hour or so on rare nights, the the sun comes up, and we begin again.

We do take them inside the house a few days a year when a frost is expected and temps have been known to drop unusually low at the burrow's rear with my approach.
The ground is neither wet nor dry.

Unless the ambient temps drop down into the 50's or below, the temp at the back of the burrow doesn't ever make it below around 65 (62 once in a blue moon briefly) because the heat rises out of the ground. Each night insulation is put at the entrance by me is why, and removed at dawn by my wife. Much of the winter the coldest it gets in there is well in the 70's.
For this reason I was letting ambient temps drop below 49 or so before implementing heating but my wife has been recently advocating 50's+.
Regardless of minutia. the back of the burrow is what I probe, and they spend the day outside of it, basking in the sun and very warm with all natural UV's and IR.

When I insulate the heat at the entrance, the temperature rises as much as I wish toward the back of the burrow. When it has not by rare accident, the tortoise has been found closer to the heat source (unable to touch it directly) again, himself, warm. It's not an idiot proof method so I'm not pushing the method. You need a probe and lots of common sense.

The tortoises have been thriving and growing under my care for years and this method was patterned after others, carefully, in the same environment, who have flawless records and giant torts and who have been breeding and keeping here since the 70's (I refuse to breed due to the crisis of people abandoning them).

I did not seek advice from them specifically about the move to the new climate because they do not really have experience where we're moving.

I suspected when I asked about these new, hypothetical possibilities when I move, I'd be told I do things current, basically unrelated things wrong, now, because folks get settled into one way and that's it.
Charles Black and I were told when we bred tarantulas they had to be at these sustained, tight-tolerance, different temps for every species across the board of they'd get sick and die etc., whereas we figured out 3 temps throughout the house for all tarantula species New and Old World had them all mating and laying eggs and we raised generations and generations without illness for years, fueling the largest suppliers.

I do think as the animal becomes old and geriatric having temps much more stable than in nature would be good for him in the way intensive care keeps people alive when they're weak.
And this setup you recommend will be what I implement up North (despite any debate about my current care) because what I defend doing here will become irrelevant, thank you.

Since it's unhealthy to let them brumate (and I am trusting your opinions on this) when we move I will keep them in thermally stable enclosures throughout the winter, at your said temps.

Thanks again.
I don't mean to be unappreciative and argue one thing when I learn another.
Even if this frustrates you or seems unappreciative, rest assured your time resulted in the tortoises being kept at your recommended temps in winter 20201-2022 and forward because you taught me the brumation option we were considering up North is not actually healthy (or normal?) yearly behavior and, if you are correct and I wrong, we supposedly dodged the bullet every other year in the current, relatively stable situation until he was 100 lbs. I did try an enclosure here, in FL, but the large one has been much happier this way, so I removed it once he settled into a burrow area that would not cave in with tree roots and I stabilized the temps into what is considered a quite gentle, healthy range by many.

He was grown to 80 lbs. (by others) without any of my thermal pampering (heaters and insulation and taking indoors) and has grown to 100 under my care in recent years with improved condition, eats and poops throughout the winter, and will be under even more stable conditions after we move, since you say he should not brumate (which he has never needed to do in this situation either).

 

[Maggie3fan]

I'm sorry that you seem to be failing to understand, example... my Bob was 120+ pounds, nice big healthy tortoise, evidently he was sick for about 5 years without showing any symptoms before he died. I would never ever leave a Sulcata tortoise in a temperature of 60 degrees under ground in a burrow where he poops and pees and creates humidity. So now he's cold and damp. In my educated opinion yes, you have dodged the bullet and been very lucky. Especially with ambient temperatures of 49 or 50?????? OMG, even my tortoises who walk out thru the snow briefly are not exposed to temperatures that low.

 

[Tom]

Thanks much --

2 things:

1)
I appreciate the help and will follow your advice when we move to the cold. This is why I research before I act, always.
I accidentally used the term estivate to describe brumate because it has not been relevant in our lives in this warm climate and I'd crossed the terms, thank you.

It never mattered until we wanted to move because they are, daily, warm and active.
I know know we should not take the approach and will just keep them warm throughout winters including when we move to the cold.

2)
I do want to say when it comes to what I have been doing now and for years, I'm dubious it's been harmful -- I believe that's a misunderstanding due to my description, perhaps making outside ambient temperature look like ones I was exposing the tortoise to (sorry).
I do not let the burrow drop to temps detrimental to the tortoises esp. for the length of time it does. The ground here is very warm with daily thermal inertia as such and it's measured with a a probe frequently.
The remote temperature probe never reports below 65 or maybe 62 or so *very briefly* during the coldest hour of the morning (in the 70's for the majority), and then --
they bask later on, in the daytime, with their shells in the hot sun, warm to the touch for hours... in the 100's to the touch for hours. They thrive this way.

Generations of sulcata tortoises in Florida above the frost line have demonstrated, in our community, they are equipped to get a little cooler breifly at night and warmer in the sun during the day, averaging them well into your described 24/7 temps and never very extreme.

Sorry if I painted a picture of them cold in their burrows for months.
The average temperature of the tortoise taken throughout the day would be the same as the 24/7 temps in your enclosures, at least, because, even in the coldest days, they are basking in the sun with the shell warm to the touch of a 98.6F human, so well above that. Then it takes all night for the back of the burrow to reach 62 coldest for an hour or so on rare nights, the the sun comes up, and we begin again.

We do take them inside the house a few days a year when a frost is expected and temps have been known to drop unusually low at the burrow's rear with my approach.
The ground is neither wet nor dry.

Unless the ambient temps drop down into the 50's or below, the temp at the back of the burrow doesn't ever make it below around 65 (62 once in a blue moon briefly) because the heat rises out of the ground. Each night insulation is put at the entrance by me is why, and removed at dawn by my wife. Much of the winter the coldest it gets in there is well in the 70's.
For this reason I was letting ambient temps drop below 49 or so before implementing heating but my wife has been recently advocating 50's+.
Regardless of minutia. the back of the burrow is what I probe, and they spend the day outside of it, basking in the sun and very warm with all natural UV's and IR.

When I insulate the heat at the entrance, the temperature rises as much as I wish toward the back of the burrow. When it has not by rare accident, the tortoise has been found closer to the heat source (unable to touch it directly) again, himself, warm. It's not an idiot proof method so I'm not pushing the method. You need a probe and lots of common sense.

The tortoises have been thriving and growing under my care for years and this method was patterned after others, carefully, in the same environment, who have flawless records and giant torts and who have been breeding and keeping here since the 70's (I refuse to breed due to the crisis of people abandoning them).

I did not seek advice from them specifically about the move to the new climate because they do not really have experience where we're moving.

I suspected when I asked about these new, hypothetical possibilities when I move, I'd be told I do things current, basically unrelated things wrong, now, because folks get settled into one way and that's it.
Charles Black and I were told when we bred tarantulas they had to be at these sustained, tight-tolerance, different temps for every species across the board of they'd get sick and die etc., whereas we figured out 3 temps throughout the house for all tarantula species New and Old World had them all mating and laying eggs and we raised generations and generations without illness for years, fueling the largest suppliers.

I do think as the animal becomes old and geriatric having temps much more stable than in nature would be good for him in the way intensive care keeps people alive when they're weak.
And this setup you recommend will be what I implement up North (despite any debate about my current care) because what I defend doing here will become irrelevant, thank you.

Since it's unhealthy to let them brumate (and I am trusting your opinions on this) when we move I will keep them in thermally stable enclosures throughout the winter, at your said temps.

Thanks again.
I don't mean to be unappreciative and argue one thing when I learn another.
Even if this frustrates you or seems unappreciative, rest assured your time resulted in the tortoises being kept at your recommended temps in winter 20201-2022 and forward because you taught me the brumation option we were considering up North is not actually healthy (or normal?) yearly behavior and, if you are correct and I wrong, we supposedly dodged the bullet every other year in the current, relatively stable situation until he was 100 lbs. I did try an enclosure here, in FL, but the large one has been much happier this way, so I removed it once he settled into a burrow area that would not cave in with tree roots and I stabilized the temps into what is considered a quite gentle, healthy range by many.

He was grown to 80 lbs. (by others) without any of my thermal pampering (heaters and insulation and taking indoors) and has grown to 100 under my care in recent years with improved condition, eats and poops throughout the winter, and will be under even more stable conditions after we move, since you say he should not brumate (which he has never needed to do in this situation either).

Thanks for the well thought out response. Sometimes people just want to be told what they want to hear, so its nice when that is not the case, and we are able to help.

I have not looked at FL ground temps. The US Geological Survey publishes annual ground temp data. In my area, growing temps even a few feet down are a consistent 80 all Summer long, and a consistent 50 all winter long. There are surprisingly brief transition periods in between of about 6 weeks in fall and spring. I verified these temp in my Argentine tegu burrows that were about 3-4 feet deep. I let them hibernate here, as they do in the wild in Argentina, and it worked very well for me. I was really surprised at how amazingly stable the temps were underground. As I said, I don't know what the annual ground temps are where you are in FL, but your data from your own thermometers is interesting. I had similar underground enclosures for sulcata that I heated and kept warm all winter, and it was surprising how much electricity it took to keep it 80 down there. The ground was a terrible heat sink and just sucked up all my heat and dissipated it.

I don't want to hijack your thread, but I'm an amateur tarantula breeder. I'll bet you could teach me a ton. I've had success with my GBB, but failed with G. pulchra. The female ate the male with a karate move that started in slow motion and ended with lighting speed as she sunk her fangs into his abdomen while I was sitting right there with tools in hand to intervene. It happened so fast that my reaction time allowed her to bury those giant fangs in him. Haven't found another MM to try her with yet. Here is my thread on the GBB. Tips, corrections and observations are welcome: https://tortoiseforum.org/threads/baby-tarantulas.177338/