Husbandry and breeding of Death Adders
Originally published in Reptiles September 2004, pages 48-60, in slightly altered form with numerous high quality photos.
Raymond Hoser
INTRODUCTION
Death Adders, genus Acanthophis are snakes that are usually instantly recognized by most snake fanciers.
These Australasian snakes are unique among the highly venomous elapids in their viperine appearance and habits.
Resulting from convergent evolution, these snakes are like the viperids in their terrestrial habits, ambush predation, thick-set build, relatively large fangs, toxic venom, earthy colour tones and other features.
However they are of the family elapidae, not viperidae.
Death Adders are found throughout all but the coldest parts of Australia, New Guinea and adjacent islands in almost all types of habitat, the sole proviso being that it must be relatively undisturbed through clearing for agriculture or heavy grazing.
Over a dozen forms have been scientifically described to date, including four species from Island New Guinea and seven species from mainland Australia.
Perhaps the best-known species is the so-called "Common Death Adder" (Acanthophis antarcticus) from the southern parts of Australia., which is a misnomer as the species seems as a rule to have significantly lower population densities than their more northern cousins.
This is the form which occurs around cities like Sydney, Brisbane, Perth and just north of Adelaide.
Other well-known forms include the Desert Death Adder (Acanthophis pyrrhus) from arid regions of the Northern Territory, Western Australia and South Australia, Pilbara Death Adder (Acanthophis wellsei), from the Hamersley, Chichester and Cape Range areas of Western Australia and the Northern Death Adder (Acanthophis praelongus) from the Cape York region of Queensland.
Lesser-known forms include the Barkly Adder (Acanthophis hawkei) from the Barkly region of the Northern Territory, the similar species Acanthophis woolfi from nearby regions in western Queensland, the so-called "Hill Adder" Acanthophis bottomi from the Kimberly and North Northern Territory and the Top-end Floodplains Region Adder (Acanthophis cummingi).
Outside of Australia, the most commonly seen species is Acanthophis rugosus, known from the Merauke area of Irian Jaya, which is similar in most respects to A. bottomi.
DNA and venom studies to date including Aplin and Donnellan (1999), Fry et. al. (2001) and Mengden as cited in Barnett and Gow (1992) tend to support the taxonomy and nomenclature used here, which is in turn based on Hoser (1998) and the many sources cited therein.
While some species are larger than others, all Death Adders are within the same general size classes.
As a generalization all species average just under 60 cm in length for non-growing adult males and a little over this for non-growing females.
The largest male specimens may attain nearly 75 cm, with a few known slightly longer than this, while the largest females may reach or even exceed a metre.
The largest specimen I have reliably measured was a female A. antarcticus from Sydney's Blue Mountains that measured just over a metre at 108 cm.
(Brian Barnett had a female A. hawkei of about 110 cm (see Barnett and Gow 1992).
Both these snakes remain available for independent measurement.
There are no other known and verifiable size records of this magnitude in existence for the genus Acanthophis and one should treat with skepticism any other such claims.
All Death Adders are live-bearers. At birth, young measure from about 13-19 cm, with most being born in the 14-17 cm range.
The actual size varies between species and also between specimens of the same species. However as a general rule, larger species give birth to larger young and larger snakes within a species also have larger young.
Mating is in the Australian autumn and spring, with young being born in the late summer and autumn.
For the tropical species, mating is thought to be in the pre-wet and with young being born in the middle to end of the wet season.
Captive breeding usually correlates with the seasons, but is primarily dependent on the heating regime employed by the keeper and as a result these snakes can theoretically be bred at any time.
FINDING DEATH ADDERS IN THE WILD
I've been in the herp game for a few decades and quite frankly nothing gives me more of a buzz than catching a Death Adder in the wild.
Sure, they are not big and mean like Taipans (Oxyuranus) or somewhat rare or restricted like the Broad-headed Snakes (Hoplocephalus), but I still like chasing and catching Death Adders the most.
Why?
Don't ask.
But put simply they are mongrel things to find in the bush.
The books say that they live amongst leaf litter or in spinifex (Triodia spp.) tussocks in drier areas. So if you go looking in these places you may find one or two.
But after years of searching, I was never able to.
However, I was able to find them when driving along roads on hot nights.
Yes, if you go to Sydney, try West Head Road on a hot night and you are in with a chance to find one moving across the road. If in Brisbane, try the Mount Glorious/Samford Valley Roads, or if in Perth, try the Canning Dam Road.
Northern Australia is riddled with roads that are literally crawling with Death Adders on hot nights.
While it'd be a good night to find just one Death Adder (Acanthophis antarcticus) if you spent a few hours on West Head Road on a good hot night, a dozen or more Death Adders (A. wellsei, A. pyrrhus or A. bottomi) is fairly routine for many good roads in the Kimberly or Pilbara regions of Western Australia.
So what is the best habitat to find Death Adders in?
Roads!
The best microhabitat?
Bitumen!
But fortunately these snakes breed like er, well Death Adders, so both here in Australia and elsewhere they are easy to get hold of without having to go and catch them yourself.
In fact they sell for so little, (usually one or two hundred dollars a piece), that it's generally cheaper to buy captive bred ones than to spend the time and money (on fuel or even airfares) to try and find them.
CAPTIVITY
Before I go on, I'd better give you the usual warnings about these snakes being highly venomous and so on.
Yes, before there was a specific anti-venom a sizeable percentage of bites were fatal. Many books state more than half!
Even if that figure is exaggerated, this still gives you an idea of the potential risks when handling the snakes.
As far as we need be concerned the most significant part of the venom is the neurotoxins, which attack our nervous system.
In other words, don't get bitten!
If you do get a "hit" the bite is relatively unusual among elapids in that the venom takes slightly longer to act (usually), but the effect is still the same ... likely death.
While there is a local pain at the bite site, this is not too bad, and in fact many of the "mildly venomous" small elapids like Yellow-faced Whip Snakes (Demansia psammophis) will give you more local pain and swelling.
You'll often get a warning of the shape of things to come if you see red track marks running along your arteries up your arm or leg.
See them and you know you've well and truly been bitten.
But having said this, even if you suspect a bite, cover your limb with a broad constrictive bandage and get to hospital fast.
Oh and don't remove this bandage until you have a huge amount of anti-venom available!
If you've been severely envenomated, the sequence of events is that usually the lungs either fill with fluid or collapse and it's death by suffocation.
Or maybe you'll simply choke on your vomit.
But well before this, you'll loose control of your voluntary muscles and so you won't be able to tell others what you feel or are thinking.
How do I know all this?
Yes, I've had a few scrapes (nothing serious yet!), and quite a few of my mates have had hits bad enough to warrant jabs of anti-venom.
A few years back Chris Hay here in Australia got bitten by a one metre A. cummingi and it took three lots of specific anti-venom to neutralise the bite.
He took a few weeks to more-or-less fully recover.
Having said this, most Death Adders are not aggressive, they rarely go out of their way to attack a keeper and due to their size and shape are easy to handle, even if they do get a bit off-side.
Although fast strikers, they will usually only strike at food or when in fear.
Captives adapt well to being handled with hooks and tongs, and as a daily routine, one finds that one never needs to actually handle or pick up the snakes with one's hands, thereby making handling risks miniscule.
If moved about occasionally, they will soon adapt to being picked up with a hook and when picked up on a hook will learn to move their body into balance to stay on the hook as you move the snake from cage to cage or similar.
This hook handling may be necessary for cage-cleaning or whatever.
HOUSING
The bad part
I'm familiar with all described forms of Death Adder and have had hands-on experience with most.
All have essentially similar husbandry requirements and so what follows can be taken as useful for all species of Acanthophis.
Firstly, I advise this: Check with your local, state and federal government authorities to make sure that you are legally allowed to have them. There are loads of laws, restrictions and the like and most are not generally known to the public. Then get your cages set-up exactly as you want to BEFORE you get your Death Adders.
The good part - substrate
I've experimented with all kinds of cages and substrate and quite frankly they seem to thrive in almost anything.
This includes cages with gravel substrate, dirt, sand, newspaper or hardened clay.
Within all this, I shy away from damp or dusty substrates because of the generic risks to snakes that such substrates cause, but must again stress that I've never actually seen Death Adders suffering from wet and dusty surroundings in their own right.
I have kept and bred Death Adders successfully on a long term basis with the following cage substrates, newspaper, other paper, gravel, hard sand, hardened clay and shredded tissue paper, so all are generally "acceptable".
Having actually tested Death Adders in a range of conditions in controlled tests (or at least as best I could), I found that a hard clay substrate with leaves or other material on top was the most preferred by both myself and the snakes.
Death Adders like to get under loose cover, from where they will coil in their ambush positions to wait for food, or even merely to rest.
In other words, try a hard clay base with say a half-inch of leaf litter on top.
The most important part - the heating, the heat gradient
But the most important thing necessary for success in keeping all species of Death Adders is heating.
These snakes not only love their heat, but invariably fail in health if not kept warm enough.
For many years I kept these snakes in large cages with submerged heating cables, separated from the snakes by flat rocks.
For young snakes, these heating cables were left on all the time, while for older or breeding snakes, they were regulated with either time switches, dimmers or both.
However times have changed and the use of Thermofilm (TM) "heat mats" is now my preferred method of heating.
These are the flat plastic sheets that heat up when plugged into a power point.
The plastic containers housing the snakes are simply placed over this.
Now I house Death Adders in small to medium sized plastic tubs (depending on the size of the snakes), with their hard clay substrate inside these to a depth of about 6 cm, overlain with a smattering of loose leaves.
My advice is have just enough leaves to keep the snake happy, but never too many to make it impossible for you to get a good look at the snake if you take a glance into the container.
Excess leaves are simply a waste!
The containers are then simply placed on the heat mats.
Of course having a temperature gradient is critical for all snakes of all ages, so I place the containers with one end over the heat mats and the rest off.
The snakes will always know where to place themselves.
You only need enough space for the snake to comfortably bask on the heat mat and the rest of the cage remains unheated.
So for example if you have a snake in a 60 cm container, you have just the last third over the Thermofilm.
The containers used for Death Adders range in size from rectangular take-away food tubs (16 cm long) for newborns to 60 cm long 60.5 litre tubs for adults.
In some cases Thermofilm will overheat, melt and cause fires, so if this is a risk use a dimmer.
But while talking heat and Death Adders, I cannot stress enough how much these snakes like their heat. I am sure that the most common causes of premature death in captive snakes is the lack of heating!
I sometimes set my heat mats well over 30 degrees Celsius and yes, often the snakes find the heated areas way too hot to sit on. The end result is that they place themselves on the transition zone from the heated to the unheated part of the cage.
Is there anything wrong with this?
I don't think so.
After all, on a sunny day in Australasia, these snakes would often be doing just this, finding a warm spot, but not in the direct heat of the sun.
And yes, by erring on the side of overheating (along with the mandatory cooler region of the cage as insurance against "cooking" your snake), you are never going to run the risk of loosing your Death Adder because you don't heat it enough.
Now any type of "shoe-box", style container is fine for these snakes provided that it's escape-proof for the snake (common sense).
The only caveat is that the container must be "flat bottomed", so that it sits flush with the heat mat. If there's an air space, you'll loose all the heat from the Thermofilm.
Because of their nocturnal preferences and ambush feeding, the snakes don't need lots of space to move or direct sunlight and are just a breeze to keep.
They really are the archetypal "low-maintenance" herp.
Sure they don't move about as much as other species, but rest assured, they still do move about enough to make them worthwhile pets.
And when they sit in their horse-shoe coils twitching their tails as a lure for food, you can't help but be impressed.
The easy part - air holes
Then there's the ventilation side of things.
Yes, all good snake cages need this.
The plastic tubs I use to house the snakes in are effectively air-tight when bought from the shops.
If you "poke" holes in the plastic with a sharp object, you'll crack the plastic, so you have to use another method.
Some people use a drill, but the risk of cracking remains.
For me, nothing beats a good soldering iron, which costs about $20 or less and makes it a breeze to punch out as many holes as you want.
(Test your method first, before going gung-ho into your cages).
I have them both in the upper sides and roof of these containers and condensation in these containers is effectively unknown!
FEEDING
This is perhaps where a keeper will notice the greatest differences between species of Acanthophis from a husbandry point of view. Some species such as A. antarcticus, A. hawkei, A. woolfi, A. bottomi and A. rugosus even when fresh out of the wild, seem to readily take mice at almost any age and if one has a choice between species, I suggest you take one of these.
A. pyrrhus, A laevis, and A. praelongus are bit more tricky in that they show a much stronger preference for frogs and/or lizards and sometimes present difficulties in switching to mice, which as a matter of course are the preferred diet in captivity and these Acanthophis species should (as a rule) only be kept if other species are not available.
Notwithstanding this, the best way to switch these more difficult specimens to mice is by the usual forms of trickery or force.
I've done almost every technique on these snakes and yes, they all seem to work.
This includes straight force or assist feeding for the really difficult specimens (yes you must then handle the snakes to do this), to the more commonly employed methods of offering a fragment of lizard or frog which has the mouse tied to it.
Most commonly however, I merely shove the rodent in the snake's mouth immediately after it's struck at the lizard fragment and started eating it, and the snake generally eats the lot. I do this with long tweezer-tongs so there's no risk to myself in terms of bites.
Long-term adult captives invariably get used to the mice and end up taking them freely and without incident.
While it's clear that most Death Adders prefer live food, I generally offer snakes dead food on tongs and they almost always take these without complaint. For long-term captives, again, this is by far the easiest and becomes mere routine.
Long-term adult captives are generally indestructible, however for newborn and young specimens it's not quite the same story, and it's here that my comments in relation to feeding are most pertinent.
Most specimens (of all ages) are lost due to the failure of keepers to heat the snakes, leading to death by secondary causes.
While this may from disease or parasite, I never cease to be amazed at how many keepers lose their young Death Adders from failure to digest food. Thus, as a general warning, one should never feed any Death Adder food that's too large, just in case the snake can't digest it.
Water-bowls and a falsehood that's gained currency
Waterbowls are something I often hear snake keepers complain about, but they certainly never give me any grief.
Yes there are ways to stop snakes spilling their water bowls and the often immense dramas of cleaning a bowl that's just been defecated in.
My (usual) adder "cages" are created by getting clay-type mud into these containers and then left for some time and allowed to set hard like rock.
This gives me the "natural" substrate the snakes seem to like.
If the snakes defecate on the surface, it's simple to scoop op the waste as well as any soiled substrate without the need to change it all.
Getting back to the waterbowl, I simply sink a plastic tub of appropriate size into the correct place, which is always the end away from the heat source (to minimize the evaporation).
The hardening of the clay thus firmly places the tub into the cage in an unspillable position.
However this tub is not the waterbowl.
The waterbowl is an identical plastic tub placed inside this one.
Thus to clean the waterbowl, all that's needed is to lift out the second plastic tub and replace it with a brand new clean one, while you then take away the old one to be washed.
It's all just too easy!
Now while talking water for your Death Adders, I've got to shatter a falsehood that's almost become "fact" here in Australia.
One of our most prominent keepers has been telling people for years that Death Adders, especially young ones are unable to find water in their cages and so must be sprayed daily for their drink.
The end point of this being that failure to spray the snakes will result in their death from dehydration.
Sure, if you spray these snakes they'll perk up and take a drink.
But no, this really isn't necessary.
Take my word on this.
I never spray my Death Adders and none have ever died from dehydration!
And yes, I regularly see them march up to their water bowl shove their snouts in and take a good long drink.
I even experimented on this and temporarily placed waterbowls on raised platforms making them almost inaccessible to the snakes. And yes, the snakes even snooped around their containers and found the water to take a drink.
Now if you have a Death Adder that looks obviously emaciated and clearly needs a drink, my advice is give it a luke-warm bath, or "drink it". But this is most likely from a separate health problem and not because of any inability by the species to find and drink water.
So what I am saying is that from a day-to-day husbandry point of view, spraying your Death Adders is a waste of time.
And as for those other keepers I see who keep their Death Adders in cages without water bowls who spray their snakes daily, well all I can say is "I hope you are enjoying wasting your time!"
One snake per cage
Finally, I should mention the ever present risk of cannibalism.
Most Death Adders are not as a matter of course cannibalistic and yes, in the past I've successfully housed groups of Death Adders together for years. However accidents do happen and it's not unheard of for one snake to mistake another for food with the result being the premature demise of one or both.
As for A. pyrrhus and A. cummingi, well, some specimens of these species are quite simply "cannibals"!
Many years back, I had an adult male A. pyrrhus who gorged himself on a few of his cage-mates that were the same size.
For each snake, he only managed to get half of the other one down before he gave up, but it was enough to kill the other. Once he took on a female A. antarcticus about half his length and held her down for a few days before regurgitating her undigested.
There was never food in the same cage.
Other keepers report similar stories.
As a result, I now advise to keep your Death Adders at one per cage unless trying to breed them.
But yes, by all means keep them in smaller cages if space is a problem. You'd be amazed at how they thrive, even in the smallest of plastic tubs.
Also it's definitely worthwhile to have far more cages than snakes. In terms of treating diseases, infestations and the like, nothing beats a nice new clean cage!
CAPTIVE BREEDING
For all Acanthophis this is fairly easy and so common these days as to be routine and unnoteworthy.
Certainly every described species in Australia has been bred on numerous occasions.
You will have to cool the snakes (meaning to drop the temperature to 20 degrees Celsius or lower for six weeks to three months) to initiate breeding.
I also advise that sexes be separated for a while as this certainly improves the prospect of successful matings.
Although male combat is effectively unknown in Acanthophis, it is clear that male snakes recognize one another and on rare occasions I have had one male bite another.
Thus the use of multiple-males to initiate matings is also recommended.
But as for other stimulants such as spraying snakes or whatever, well, they're plainly superfluous and I've never tried them to initiate mating.
Put it this way, sometimes it seems that most Death Adders spend half their lives trying to get laid!
Notwithstanding what I have already said here, breeding failures usually result from overheating of the adult snakes, and it is here that I should make a few more important points.
The need to give access to constant high temperatures is most important for young and newly captive snakes. This requirement is not so important for long-term captive snakes, which also as a matter of course can withstand prolonged fasting in a captive situation as normally occurs in a cooling cycle.
Snakes kept too warm will either not breed or if they do, the females will invariably pass a higher than usual number of unfertilized ova and/or fatally deformed young.
If in a cold climate, and not heating the snakes at all, or for only part of the day, the room the snakes are kept in should have a thermostat attached to a heating system that will warm the entire room to somewhere between 15 and 20 degrees Celcius in very cold weather.
The closer one gets to the higher end of this spectrum the better as the lower temperatures may increase the risk of colds and other complications arising.
Mating is "normal" for snakes in that males tend to indicate their willingness to mate by pacing their cages excessively and will normally mount a female as soon as they are introduced.
When in mating mode, a male will mate with a female more than once and so if using one male to mate several snakes, it's probably best to run him from cage to cage after known mating has taken place.
Overfed males do not mate as readily as leaner ones and while it's generally preferred to have well-fed snakes, coming off the food for the males prior to planned mating is not such a bad thing.
However as a matter of course, the males are merely starved for a period following the cooling period, whereupon they seem to naturally turn their attention to other things ... like mating.
Also with Death Adders, it seems that almost all females produce young without incident, provided they mate with a fertile male, but while they appear to be sexually mature at about 30 months or less in captivity, breeding of snakes under 48 months (4 years) is relatively uncommon.
However with males, there are definitely some that mate all the time (or so it seems) and others that just don't seem to be interested.
Thus if you are intending to breed these snakes, I suggest that you start off with more than one male and if space is at a premium, then get rid of those who don't seem to perform.
I'll spare you the details of the breeding itself, save for the general advice not to overheat your females after they've been mated, even though you must still provide some warmth for them via the heat mat.
Suffice to say that you can expect from about 8-25 live young per adder if all goes well and that many females will only breed every second season ... no matter what you do.
And because of the genetics of the snakes, the young may not come out the same colour as the adults. There actually several reasons for this, but way back in the 1980's I discovered that the determinant of the red or grey base colour (seen in the vast majority of Death Adders) is determined by a simple dominant/recessive relationship (see Hoser 1985).
While talking Death Adder papers, there's loads of them covering all possible aspects of Death Adders on my website at:
http://www.raymondhoser.com
HEALTH NOTES
Get hold of herpers encyclopedia of snake diseases and you can bet that Death Adders get most.
But from a practical point of view, if you cover your bases as indicated above, you are likely to have few if any troubles. Like I've said, young Death Adders just need a bit of tender-loving care and the biggies are practically indestructible.
The most common problem is mites.
These can really thump Death Adders and anything under 30 cm is likely to die from a half-decent infestation that's left untreated for more than few days.
I've usually used pest-strips to kill the mites and without loss of snake to date, but suggest care be taken as the ingredient of note "Vapona" is known to have killed snakes when in high concentrations.
My method is as follows: Using a number of containers/cages, I first isolate the snake with a section of strip for an hour in a smallish empty container (keeping the snake under continual observation, noting that live mites should start to die and fall off the snake within 20 minutes) and repeat this every few days for 40 days. The continual observation is in case the snake starts to suffer (e.g. gasping), in which case the treatment should be stopped (I've never had to do this for the Death Adders).
The original (infested) cage/container is sealed with a strip inside it for 40 days.
The methodology here is that the Vapona kills all mites and intermediate stages, negating any need to clean and disinfect cage or furnishings as per other mite treatments.
The snake is then housed in yet another relatively bare container that is itself treated with a decent chunk of pest-strip every few days, at the same time the snake is placed in the bare box.
Vapona is good mite-killer and you only need to be able to get a slight whiff of the stuff and it'll kill mites. That's the dosage required. (Try 2 cm X 2 cm in the well-ventilated shoebox with the snake for the hour treatments and that should be fine).
The room the snakes were in is sprayed with insecticide and the snakes moved to another previously treated site.
While under treatment for mites, the snakes sit in plastic containers with a few pieces of paper as substrate with a large "dog bowl" style dish for water. And yes, they seem to cope fine, including feeding and the like.
Besides the usual indicators of mites, for Death Adders, the warning signs include excessive digging, especially by using the snout and getting it either rubbed or covered with dirt and jumping in the water bowl, which is something Death Adders otherwise avoid.
You are likely to see one of these before you actually see the mites or their droppings in the cage or water.
As a health complication from mites, Death Adders may have trouble sloughing. This is generally resolved with a soak in warm water at the time of shedding (when due). In normal circumstances, shedding problems for Death Adders are effectively unknown.
Contrary to my above statements re Death Adders and drinking, it is when treating Death Adders for mite, that it may be advisable to actually "drink" the snakes in luke-warm water to assist in recovery, particularly if the snake is severely emaciated as a result of heavy infestation.
The only other half-frequent health complication for Death Adders are intestinal worms, such as tapeworms and these can usually be eliminated via the usual dog and cat treatments at a reduced (by weight) dosage.
THE FRONT SNAKE
When the air pressure falls and the weather starts to change, all reptiles seem to become a little bit more active.
However I doubt that this change is as marked in any snakes as much as the Death Adders.
If you have them in your home, you'll notice that they go from sitting around apparently doing nothing, to suddenly becoming incredibly active.
Weather it's food, sex or something else, these snakes really do go out and about when the weather changes.
And as you watch your Death Adders strut their stuff, you'll never regret having brought them into your home.
REFERENCES CITED
Aplin, K. P. and Donnellan S. C. 1999. ‘An extended description of the Pilbara Death Adder, Acanthophis wellsi Hoser (Serpentes: Elapidae), with notes on the Desert Death Adder, A. pyrrhus Boulenger, and identification of a possible hybrid zone’, Records of the Western Australian Museum 19: 277-298.
Barnett B. and Gow, G. 1992. 'The Barkly Tableland Death Adder.' Monitor - Bulletin of the Victorian Herpetological Society 4(1):13-23
Fry, B. G., Wickramaratna, J., Jones, A., Alewood, P. F., and Hodgson, W. C. 2001. Species and Regional Variations in the Effectiveness of Antivenom against the in Vitro Neurotoxicity of Death Adder (Acanthophis) venoms, Toxicology and Applied Pharmacology 175, 140-148.
Hoser, R. T. 1985. Genetic composition of Death Adders (Acanthophis antarcticus: Serpentes: Elapidae) in the West Head area, Herptile, 10 (3):96.
Hoser, R. T. 1998. Death Adders (Genus Acanthophis): An overview, including descriptions of Five new species and One subspecies. Monitor - Journal of the Victorian Herpetological Society 9 (2):20-41.
Raymond Hoser a long-time Death Adder fancier, has been at the leading edge of Australian herpetology for more than 20 years. He's authored nine books and numerous articles.
Death Adder Caging - Photos of the exact set-up used by Raymond Hoser (2002-2003) - Click here.
Death Adders - Internet portal with all the best papers, articles, photos, websites, etc. - Click here.