Tortoises which emerge from hibernation (technically it is more correct to use the term 'brumation', through for the sake of familiarity and brevity we use both terms here) with health problems are in serious - and immediate - danger. For a variety of biological reasons, tortoises are at their most vulnerable at this time. In particular, the white blood cell count is very low (thus reducing their ability to fight infection), and the blood urea level is also often very high due to metabolic toxins accumulated over the hibernation period. This combination of a low white blood cell count and high blood urea, at a time when other body functions are also not functioning at peak effectiveness does mean that should anything go wrong, the time available to treat and correct the problem is considerably less than normal.
It is therefore extremely important that tortoises which fail to function normally as they come out of hibernation are detected quickly and given prompt, effective treatment and support.
There are several factors to consider in connection with hibernation. Each of these is critically important to the survival and well-being of the tortoise.
TEMPERATURE in hibernation.
Freezing is the biggest killer of hibernating tortoises by far. If the tortoises body temperature reaches freezing point at any time during the hibernation period, death or very serious injury will invariably occur. Do not make the mistake of believing that insulation alone will protect your tortoise - it won't. It merely slows up the rate of heat exchange. Prolonged spells of sub-zero temperatures will kill no matter how well insulated your tortoise is. The only way to offer complete protection is to use a reliable thermometer and never, ever, leave the tortoise exposed to dangerously low temperature. If the temperature does fall to dangerous levels, move the tortoise to a safe location at once. The ideal target temperature for hibernation is circa 5°C.
DURATION of hibernation.
Tortoises in the wild typically hibernate for between 8-12 weeks, though this depends greatly upon the species and locality. If you hibernate your tortoise for longer than this, then you are placing it as serious risk. The smaller the tortoise, the greater the risk (it's body fat and fluid reserves are less).
CONDITION of the tortoise.
Sick or underweight tortoises should never be hibernated. They will not survive. Always perform a detailed pre-hibernation heath check to ensure that the animal is a) up to a safe weight and b) is not displaying any signs of disease. Sick or underweight tortoises will need overwinter care indoors, with adequate light and heat to enable them to function - and feed - normally.
For complete details of recommended hibernation conditions and a very detailed guide to how to carry out pre-hibernation health checks, you should consult 'Safer Hibernation & your Tortoise'.
This article however, concentrates upon what to do if you have noticed problems. Firstly, if your tortoise is 'late' in getting up, do not assume that all is well. Check it immediately. Often a sick or frost damaged tortoise will not get itself out of hibernation. If left without help it will simply die. Certainly, no tortoise should in our opinion ever be in hibernation later than the end of March. If your tortoise is still 'in hibernation' when ambient temperatures in early spring are much above 12°C or about 60°F then it may need help urgently. Don't delay. Act immediately.
First Steps
The first thing tortoises really need to do on emerging from their hibernation is to drink. Not only will they naturally be somewhat dehydrated, but due to the accumulation of toxins during hibernation the kidneys need a throughput of fluid in order to 'flush' these away. The main waste is uric acid. This is a white, crystaline substance which in a dehydrated animal looks a bit like thick emulsion paint or even like powdery chalk. If a tortoise is allowed to become acutely dehydrated, this substance can cause very serious damage to the kidneys and the bladder. It is very important that it is flushed out as quickly as possible. Drinking is therefore very much more important at this stage than feeding.
Many people experience problems in getting tortoises to drink - in fact almost all tortoises will drink provided water is offered in a suitable manner. We recommend placing the entire tortoise in a sink or washing-up bowl filled with about 25mm or I" of very slightly warm water - less in the case of very small tortoises, a little more for giant specimens. Simply offering a small dish of water to the tortoise is not likely to stimulate a good drinking response, but actually placing it in water is usually successful.
See our recent article on 'Hydration and your Tortoise' for more background on this topic.
The tortoise must also be kept warm for at least 8 hours per day. An ideal temperature is between 22°C - 25°C. A basking lamp such as a suspended 150W basking lamp about 25cm or 10" above the tortoise will definitely help if the outdoor temperatures are cool and the weather dull - it is absolutely vital that such temperatures are maintained in order to speed up activation of the tortoise's digestive system and metabolism.
In general, the steps required immediately after waking are exactly the same as explained in our article on 'Overwintering Tortoises Successfully'.
While for longer term indoor use, it is really very important that the correct combinations of lamps are used to provide the fullest possible spectrum of infra-red, UV-B and UV-A, for short term, temporary use after waking where the absolute priority it to get the tortoise warm, much simpler lamps are acceptable. For years, a basic incandescent 120-150W PAR 38 flood lamp was popular, but now, due to environmental restrictions these are no longer readily available. The best current option is probably a halogen flood lamp specifically sold for reptile use. Mercury Vapour basking lamps also work well - but be advised that we do not recommend these for long-term, routine use. To simply warm a recently emerged tortoise up, however, they do work.
As the tortoise awakes certain biological changes take place; one of the most important of these is the release into the bloodstream of a chemical called glycogen, which has been stored in the liver. This provides extra energy to give the tortoise an initial 'boost'. Feeding must take place before this is exhausted, or the animal will begin to decline.
All tortoises should very definitely feed within ONE WEEK of emerging from hibernation. If they do not there is either,
a) A health problem,
or
b) A husbandry problem.
If your tortoise is not feeding by itself within one week of waking up, do not delay - consult a veterinary surgeon who has particular experience of reptile husbandry, physiology and treatment. Seek the underlying cause of the problem,and do not be satisfied with non-specific 'vitamin injection' therapy. There is always a logical and very good reason for a tortoise persistently refusing to eat, and generalised vitamin deficiencies are highly unlikely to be responsible. Good diagnostic techniques, combined with an understanding of reptile metabolism and function, will invariably produce a satisfactory answer.
For more details of some common health problems, you should consult 'Safer Hibernation and your Tortoise' referred to earlier. The following information however is of special relevance to frost damaged cases.
Frozen tortoises
Most tortoises which are subjected to sub-zero conditions die as a result. Some, subject possibly to only peripheral freezing may survive however. These usually sustain at least some physical damage as a result.
The most commonly encountered problem is loss of vision due to the eyes freezing. The actual damage may involve the lenses or the retinas, and the consequences range from partial sight impairment to total blindness. A sight damaged tortoise behaves abnormally:-
It may not move around very much. If it does walk, it may bump into objects or fail to recognise its food.
It may not react normally to visual stimuli, i.e. a hand waved close to the eyes may not produce the unusual head-retraction response.
Sight damaged tortoises usually will not feed themselves.
The tortoise may move in circles or hold its head at an unusual angle.
One or more of these symptoms may be present in any combination. If you hibernated your tortoise in a garden shed for example during the extreme cold of last winter and it now displays symptoms like these, there is a very high probability that it has indeed sustained frost damage. Note that this sort of eye damage requires expert diagnosis - without a proper examination using special equipment the eyes may appear to be perfectly normal.
TAKE THE TORTOISE TO YOUR VET WITHOUT DELAY AND REQUEST AN OPHTHALMIC TEST. USING AN OPTHALMASCOPE, FROST DAMAGED EYES CAN USUALLY BE DIAGNOSED IMMEDIATELY.
The prognosis is very variable. Some cases recover completely reasonably quickly, other can take years. Some never recover. It very much depends upon the severity and extent of the damage sustained.
Emergency first aid
Dehydration is the most immediate danger. as above. We often use Hartmann's solution (an I.V drip compound sodium lactate) given orally at 5% of total bodyweight daily in cases of severe dehydration, reducing as urination begins and the electrolyte balance is restored. Fresh, plain water may also be used. Please consult your vet as the correct dosing and duration can depend upon renal status and blood tests. If in doubt, begin with plain water only. Addressing dehydration as rapidly as possible is absolutely critical, however.
Long-term care and maintenance
There are times when it may become necessary to resort to either force or hand feeding; particularly so in the case of sight damage or where a tortoise for some other reason is unable to feed itself. Fortunately tortoises do not find this as distressing as mammals, and from the owner's point of view the procedure is both safe and relatively simple. We classify force-feeding in three basic stages; hand-feeding, which is really no more than an encouragement to feed normally; syringe feeding, which is less time-consuming and where alternative foods can be employed; and finally, stomach-tube feeding, where semi-liquid food matter is introduced directly into the digestive system by means of a tube passed down the animal's throat.
We will discuss this in more detail in a following article.
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