Some Notes on Blotched Bluetongues (as at 9/2/17)
Blotched bluetongues, or Blotchies as we like to call them are found in the south eastern corner of the mainland of Australia, Tasmania and the islands of Bass Straight (between the mainland and Tasmania). Their range extends over approximately 2000km (1200 miles), ranging from the New England Tablelands in north eastern New South Wales to the southern tip of Tasmania.
Blotchies inhabit cool temperate to sub alpine areas. As a rule, areas where they are found have high to moderate and consistent rainfall, cool to cold winters and warm summers.
There is only one living species of blotchie, Tiliqua nigrolutea (meaning black and yellow). Although the species varies considerably across it’s range and the name is not a good description. The species is generally thought of as broadly separated at an enthusiast (not recognised scientifically) level into highland and lowland forms. In reality graduation of forms occur across the range. The keeping requirements of all forms are similar.
Blotched blueys are arguably the most tolerant species of Tiliqua of a wide range of temperatures and keeping conditions. Tolerances and factors influencing their survival and breeding important to understand for either indoor or outdoor keeping.
In cooler southern areas blotchies can be found at low elevations. They are common in coastal heathlands, whereas those from more northerly latitudes (closer to the tropics in the Southern Hemisphere) are restricted to cooler, elevated areas where temperatures and rainfalls are more like those further south. Across their range individuals can be found as high as 1300m above sea level and possibly higher. I recently found a dead one on the road outside of the Thredbo Ski Resort at Mount Kosciusko.
In southern and eastern Australia they are widely kept outdoors in walled enclosures, which often referred to as pits. Generally they are happy to live in conditions that would make Eastern blueys (T.scincoides) perish due to extremes of cold and heat. This is despite that fact that the two species occupy much of the same range. They are “generally” free of medical conditions that plague other species related to cold, namely Easterns, Shinglebacks (Stumpies) including respiratory infections, toe infections and the like if kept under less than ideal situations.
Temperatures within their natural range (generally measured at 1 metre above the ground) range from -10C (14F) to 43C (110F), near or even slightly above the snow line. At both ends of their survivability spectrum, survival depends on microhabitat choices by the bluey.
Fundamentally it should be understood however that they are not Northern Hemisphere animals. If their body temperatures drop below freezing, they die. If they get too hot, they die. Animals exposed to ambient temperatures greater than 43C will likely die.
For the most part, extremes of temperatures in their natural habitat are the exception to the rule. In many areas where blotchies are found temperatures rarely drop below freezing but are often cool for prolonged periods eg. Tasmania.
Blotchies are found in areas where daytime temperatures always rise above freezing during the day, at the coldest part of the year.
If given the choice, blotched blueys will choose temperatures that are very similar to other species although preferences vary between individual animals in the same way as other species. Preferred body temperature appears to be approximately 32C.
One key factor in keeping blotchies however is that if temperatures are allowed to drop below 23C (73F) for a period of successive days – this can initiate brumation, or at least put them off eating until they are maintained above this temperature for several days. This is probably an adaptation to their habitat which can turn cool even in summer – their ability to digest food is linked to their metabolic/enzyme activity. If they eat and then stay cold – they will die.
A tip for young players is when keeping blotchies is to focus on the cool end of the enclosure rather than the hot end.
Blotchies drink and wee a lot compared to other species. I believe that one of their moisture requirements are a key reasons why they are found in cooler wetter areas than other species.
Baby blotchies dehydrate easily and are quite large (eg. 30+ grams at birth) and soft skinned. They benefit from access to moisture, humidity and/or baths when shedding. Shedding is often more like T.rugosa aspera and often under conditions where they can get adequate humidity, the skin will shed, more or less in one piece. Babies in dry conditions can end up like a stuffed sausage, unable to shed. This is less of a problem with mature individuals as they are often very robust.
Substrates for indoor keeping should be well aerated and absorbent. Recycled paper cat litter is often used. Attention is generally not required to humidity levels for adults when they are not actively shedding which expands the choices of substrates available over other species.
In their natural habitat, blotchies will brumate for up to 6 months of the year. In the wild they curl up in a circle/semi-circle, partially or fully buried in soil under clumping grasses, logs or other structures. Often they will find what appears to be a ridiculous spot, in the open, or even in wet mud. It doesn’t seem to matter, as long as they choose the spot. Often they can be picked up and moved to somewhere people think is more appropriate, only to go back to the same spot.
Sometimes blotchies just have to be moved, particularly if they have chosen to brumate in a spot that floods. This is more common than you might think in an outdoor enclosure due to solid walls that can prevent water flow. They are beautifully adapted to their natural environment – not enclosures.
Soil contact by the bluey to buffer temperature fluctuations is the keys to blotchies surviving brumation outdoors where sub-zero overnight temperatures are experienced. In Australia we don’t get permafrost, there is always residual heat above 0C in the soil which seems to be the key to their survival. They can even survive direct light frosts on their skin.
This is not a particularly safe brumation practice in an environment with introduced foxes and probably the key reason they tend to disappear from urban fringe areas – puts them in the Darwin award category. So if you are keeping them in an outdoor enclosure in Australia – make it fox and dog proof or you will probably need to buy a new bluey in Spring.
When keeping blotchies indoors, if you want to stop them brumating then you will need to maintain temperatures at the low end of the enclosure so that they don’t fall below 23C. This will keep them eating through the year. I find that this is important for young blueys in their first year. Babies kept in human made enclosures will invariably have interrupted brumation and will be up and about on warmer days – even as low as 10C.
If you are planning on breeding them, they will need to be cycled – that is, allowed to cool and then warmed. There is a whole paper to be written on breeding.
Blotchies are the pigs of the Tiliqua world. They are often inquisitive, can be aggressive to people and for the most part unconcerned about other blueys attempting to feed at the same time. Many will happily eat from your hand, and even identify a particular person when they walk in the room. They don’t take long to realise when they are about to get fed.
In contrast, Easterns will often wait for you to leave the room before eating – content in the knowledge that they have convinced you that they are actually a stick.
Blotchies have a thing for mushrooms and snails, but are just as happy on a diet of pure dog food. I find that loaf type consistency dog foods are best – less mess, waste. Often with wetter types, they will sit and just lick the jelly off, particularly the more fussy eaters. They will also eat dry dog food, but in small amounts. Dry dog foods are generally poor quality, maze based with added back processed fats.
Cut up fruit, particularly apples that would otherwise go in the bin are also a favourite when cut into small pieces. For a bit of sport they love a cooked chicken carcass – they are not dogs. The long bones are swallowed whole and readily digested by these reptiles – simply remove the carcass when they are finished.
Another tip for keeping blotchies is to not be too concerned about them being a little overweight, particularly if they are going to be brumated outdoors. They are going to need the fat, and generally breeding is more successful with heavier females when it comes time to wake.
Males can be difficult to start eating after waking from brumation, typically they have one thing on their mind – it’s not eating. They can take from September to December to actually eat anything males can die from undernutrition at this time of year.
Tips to get them eating are to feed them what they want to eat. Typically, raw meat, cooked egg, or snails can start their engine. Once eating, mostly they continue to eat regain weight.
Unlike other species, blotchies are happy to live in a communal enclosure – most of the time. Collective happiness however can be dependent on getting the mix of personality’s right in the individuals – some are just plain aggressive and need to be kept on their own or sent to live on a farm. A large male blotch (particularly highland forms) can be big and aggressive enough to kill or maim other males or cause excessive damage to females in the mating season. So they will probably need to be separated.
It is a good idea to have a spare enclosure, or simply some large containers and a cool place to keep them potentially for a few weeks to cool off.
Some other things to think about with communal keeping are that you won’t be able to control the breeding such as male selection and if you get pests such as mites the problem is that much worse to resolve.
If you are breeding, you will need to remove babies quickly because they will be eaten. Generally you will have one to two hours to remove the babies before the mother will eat them. In a communal cage others will eat them straight away and will often hover around a mother giving birth for a greedy snack of birth sack.
If you are looking to breed, you should first think about your motivations and what it is that you want to produce. You are going to need to be committed to all stages of the process which means properly looking after the adults, the babies and take responsibility for what you breed.
You need to be in control of your collection and provide for their needs. It is not a good idea to establish a group of blotchies and attempt to introduce other species, forms etc. You will end up in a mess of uncontrolled breeding, damaged blueys and intergrade forms (eg. lowland and highlands), or dead other species such as Easterns.
Start small, build up, don’t jump in head first. Make sure you are set up for babies and understand their needs. This also goes for the females, as they can often give birth immediately prior to brumating – so don’t get a chance to put weight back on. This can literally be a life and death problem and will at a minimum result in breeding failure in the subsequent year as generally only well-conditioned females will breed.
Generally getting blotchies to breed in southern Australia isn’t brain surgery. They work it out themselves.
Some years are better than others – generally a consistent lead up to warmer weather in Spring will give better results. Poor breeding years tend to be those with prolonged periods of hot or cold weather, such as a run of hot weather followed by a cold period.
Mating tends to start in the first month where the average daytime temperature reaches about 23C. Mating activity will be seen on the warmer days within this period – typically 25C and over and initially in the afternoons.
During the mating period, males will fight if kept together. In general males will not be successful at mating until their 3rd year – although size may be the determining factor. A common sight is a small male being piggybacked around the enclosure by females who are often twice their size.
A hierarchy will develop, often with one, or even two dominant males in a group. The presence of more than one male seems to increase mating success. This is possibly due to increasing competition and influencing hormone levels in other males.
Heat and Birth Defects:
A common problem with keeping blotchies outdoors in Southern Australia is difficulty regulating heat. A female Alpine blotched can be a large lizard (up to 1.3 kg, or about 2.9 lbs) and when heavily gravid they can suffer significantly, deaths do occur.
One of the more common return purchase requests to myself as a breeder is death of purchased animals due to heat exposure in poorly constructed enclosures where blueys have literally been cooked.
Prolonged and multiple exposures to high temperatures lead to stillborn babies, retained (unexpelled) dead babies, and increased risk of physical abnormalities in babies. Common problems include spinal bending, eye problems (eg. Born missing an eye), external organs, missing limbs, or even pronounced otherwise minimal genetic predispositions eg. undershot jaws.
I hope this helps our scaly buddies in the future.
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- Great Scott
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If you wait, all that happens is that you get older. M. Andretti
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