Successful keeping and breeding of Eastern Brown Snakes (Pseudonaja textilis)  including an assessment of previously documented failures and reasons for them.

ABSTRACT

In spite of their abundance in the wild, Eastern Brown Snakes (Pseudonaja textilis) there is only one published paper detailing the breeding of the species in captivity. That paper (Banks 1983), now more than 2 decades old, detailed a number of unplanned egg-laying’s over a long period in snakes held on public display at Royal Melbourne Zoo. For the first time ever, this paper details a planned and successful breeding of the species using modern keeping methods that can be emulated by anyone else intent on breeding this taxa. The emphasis here includes the temperature regime given to the breeding snakes in the 12 months prior to breeding, which has not been documented for the species previously.
To date all records of incubation of eggs for this species have reported low hatch rates. This paper reports a high hatch rate and gives reasons for previous failures with regards to this species. It also gives two important means to avoid losses of otherwise fertile eggs which has occurred in terms of previous breedings.

INTRODUCTION

The Eastern Brown Snake Pseudonaja textilis (Dumeril, Bibron, and Dumeril, 1854) is a swift moving snake found in all mainland Australian states.

It is without doubt the most commonly seen snake in many areas, save for the colder regions and far west. 

The Eastern Brown snake has a flesh coloured buccal cavity, as opposed to a blackish colour found in the Western Brown Snake, with which it may be confused.  Averaging about 1.6 metres in non-growing adults the dorsal colour may vary, but most specimens are an even brown.

The scalation is smooth with 17 mid body rows, 85-235 ventrals, divided anal, and 45-75 divided subcaudals (Hoser 1989).

This species has extremely toxic venom, but fortunately it's biting apparatus (fang length) is not as long as in most other deadly snakes and hence bites through clothes are rare.  It injects relatively little venom in most bites and it's fangs are relatively short, although they can still easily penetrate the human skin if unprotected by clothes. Brown snakes are fast moving and potentially highly aggressive.  When aroused a Brown Snake will hold it's neck high, slightly flattened in an S-shape and strike repeatedly at it's aggressor.  This snake will occasionally chase an aggressor away, striking at it at every opportunity (Hoser 1989). 

Similar species to Pseudonaja textilis and assigned to the same genus, include the following:

1.       Pseudonaja elliotti Hoser 2003, from Western New South Wales is effectively unknown save for it’s basic husbandry in captivity and the habitat where the holotype and paratype were found.

2.       Pseudonaja inframacula (Waite 1925) from South Australia’s Eyre Peninsula and nearby has been recognized as a distinct species for some time.

3.       Pseudonaja ingrami (Boulengeri 1908) from northern Australia may be a species composite.

Breeding biology of these taxa is little-known or effectively unknown but is inferred to be similar to that for P. textilis.

Likewise for the similar Pseudonaja affinis from south-west Australia, that may in fact include two similar taxa.

Several subspecies of P. textilis have been described (see Hoser 2002). 

These are:

1.       Pseudonaja textilis textilis (Dumeril, Bibron and Dumeril, 1858) the type species from Eastern NSW and nearby areas.

2.       Pseudonaja textilis bicucullata (McCoy, 1879) from Victoria - a slightly smaller variant than the nominate subspecies, which includes the specimens from south-west NSW, including areas such as Albury and Wagga Wagga.

3.       Pseudonaja textilis ohnoi Wells and Wellington, 1985 from Central Australia. Believed to be restricted to the McDonnell Ranges of Central Australia, (other taxa as first identified by Gillam (1979) occur north of here).

4.       Pseudonaja textilis pughi Hoser, 2002 from island New Guinea.

Other subspecies of P. textilis were undescribed in 2002, most notably that from the Adelaide region.  That form has distinctly smaller venom glands (relative size), smaller hemipenes in males (relative size), strictly paired subcaudals (none single at the anterior end), a more distinct ventral patterning in the forebody (compared with P. textilis bicucullata) and reddish hind-belly, and is generally faster moving then other P. textilis.

As for other P. textilis, the Adelaide specimens had a reputation for intractability in captivity, as in they try to bite their captor and/or run away at every opportunity.

However two specimens acquired from Adelaide in late 2005 and made venomoid within a few weeks after arrival, soon became very docile under a regime of “free handling”.

Because snakes of the genus Pseudonaja account for about 40% of snakebite deaths in Australia (most attributable to the species P. textilis) and the fact that the species is regarded as aggressive (will bite) to humans, they are not a popular captive.

Hence most captives are a small number of specimens, usually kept singly or in small groups that are used for public exhibitions (i.e. zoos) or mobile reptile demonstrations.

Because young specimens of this species have a reputation for being difficult to induce to feed voluntarily and to raise in captivity, most specimens seen in captivity are wild-caught adults.  They are simply less bother for the keepers.

The apparent worthlessness of these snakes is seen by the fact that in South Australia for example, licenced reptile controllers are allowed to keep and sell specimens of this species that they remove from houses to a maximum of five per year.  This number is generally far less than is caught (the species represents most of the snakes removed from properties in Adelaide and environs).  Notwithstanding this five snake limit (per catcher), this number is far in excess of the annual demand for the species Australia-wide, the result being that the “quota” is rarely filled because quite simply, no one wants these snakes. 

Because of the various restrictions on taking wild snakes in most parts of Australia, the majority of Eastern Brown Snakes seen in Australia in captivity derive from this South Australian stock.  However amnesties elsewhere (most notably in NSW) have resulted in an infusion of stock from other parts of Australia.

Added to this infusion of non-South Australian stock has been a tendency for keepers to “swap” aggressive South Australian snakes with more tractable specimens from other parts of Australia.

When caught, all regional races of P. textilis will try to bite and due to their fast movements are regarded by many experienced herpetologists as one of the most dangerous species. 

Internet postings routinely reflect this viewpoint.

Rarely do inexperienced herpetologists even dare to tackle adults of these snakes in the wild state.

In captivity, the experience of most herpetologists is that the aggression increases.

This is certainly the case with newly caught snakes that find themselves confined to a box and then strike at people or anything else that passes their cage.

In fact, it is usual for the “aggression” level to increase in the hours and days following capture.

This reinforces the general view that these snakes are intractable and aggressive and not worth keeping.  Some authors regard these snakes as having the most toxic venom of any snake known and regardless of the exact ranking (1, 2, 3 or whatever), the ranking is always high enough as to instill fear in people.

The experience of most keepers who have kept the species is that some, but by no means all Eastern Brown Snakes will settle down to the extent that a “working relationship” is achieved between keeper and snake to the extent that there isn’t a wrestling match between the two every time the snake needs to be moved, cage cleaned, or whatever.

The usual end result in terms of long-term captives is an effective “stand-off” whereby cage cleaning is restricted to times that the snake is inactive or safely in a hide-box.  Feeding is with long sets of tongs and most snakes are kept in top-opening boxes that make it difficult for the snakes to lunge at the keeper.

The situation whereby a keeper can “free-handle” an Eastern Brown Snake has until recently been rare, but not unheard of.

This result was attributed (perhaps erroneously) to the idea that the species is generally intractable to captivity and humans.

The reality is that they are generally more nervous than other snakes and in terms of humans this tends to manifest as “aggression”.

Because the species is dangerously venomous, seen to be aggressive to humans and regarded as intractable, it is routine for the snakes to be handled with pinning sticks and hooks and by tailing and necking.

The alternative is seen as a fatal bite.

Venomoid operations as documented by Hoser (2005) and later papers changed this situation in snakes held by the author to the extent that there became no risk when handling this species save for a harmless bite leaving a couple of fang marks. 

In terms of this and all other species used in demonstrations that had been subjected to the venomoid operation, the following became true.

Snakes were often grouped to more than one individual per cage or shipping box.  Due to the fact that snakes have very strong interactions with one another (not generally noticed by people), snakes seem to be more pre-occupied with one another than the human handlers.  The result is that within a short period (measured in days or weeks) the snakes become less aggressive to humans.

In terms of venomoid snakes this is significant as the risk of fatal snake-snake bites is eliminated, enabling the handler to rapidly calm down otherwise “aggressive” snakes.

Coupled with free-handling, which is less stressful for the snake as compared to the alternatives of necking, tailing, hooking, etc, the snakes also lose their fear of humans.

The rapid speed at which free handling calms down previously agitated, highly strung, hook handled snakes is unbelievable to those not familiar with this transition.  The timing of this is often measured in minutes, rather than hours or days, at least to the extent that a change in the snake’s responses is obvious.

With snakes becoming less highly strung towards their keeper, their other captive behaviors tend to improve, including feeding, breeding and the like.

As a result of these facts, the two Eastern Brown Snakes subject of the breeding report in this paper have become so tame and tractable that they never attempt to bite (even if rough handled), and can be free-handled by any person (even with no snake experience) and make no attempt to bite or flee in fear.

(The two relevant snakes actually go out of their way to avoid biting and no bites have ever occurred from this taxa in spite of daily free-handling).

In terms of handling for management, housing and the like, both snakes are simply picked up (from anywhere, but usually mid-body), free handled and moved about.

When packed in small boxes (click-clacks) the snakes are merely held and bunched up and shoved into the box.  Not only do they not attempt to bite, but they actually go our of their way not to bite, by holding their mouths shut tightly.

This is relevant in the context of this paper in that their high degree of settlement in captivity enabled other activity such as mating to be engaged in willingly and regardless of movement and observation by myself and others.

BREEDING STOCK

As a result of acquiring a Victorian Demonstrator’s licence in the period 2003/4, I needed to acquire various deadly species of snake, including all the common types from Victoria.

Included here were a pair of adult Eastern Brown Snakes (Pseudonaja textilis).

Although acquired via a circuitous route, the two adults had originated from about 25 km north of Melbourne’s CBD.

Both snakes were typical of the species from Victoria (as in Pseudonaja textilis bicucullata (McCoy, 1879)) (see Hoser 2003). Both were aggressive to humans when acquired.  Unlike P. textilis textilis from the Sydney area and most other parts of their range (including most of South Australia) that routinely coil around prey when biting (as in “constrict”), this subspecies rarely does this and if it does, the coiling is usually only brief and partial (more in line with pulling the prey item in as opposed to constricting) and occurs when the snake is particularly hungry.

In line with what has been found to be normal for the species, the male was originally more nervous and more aggressive to humans than the female.  While there is strong individual variation in snakes, this trend is true for most of the larger elapids.

Both P. textilis subject of this paper measured just under 120 cm total length (four feet) when acquired and were just over this length by mid 2005.

In early 2004, the male was made venomoid using the procedure outlined in Hoser 2004a.  The male snake was shown being operated on in that paper (Hoser 2004a) and has since graced the cover of Crocodilian.

The female was made venomoid in January 2005.  It had been incorrectly assumed the snake was a male prior to this date based on size and the appearance of the tail and it was only at this time it was probed and accurately determined to be a female.

In the photo with this paper, the female presents as a much darker snake, but this is not so.  The colour merely reflects it’s stage in the shedding cycle (a slough being imminent).

Usually both snakes are exactly the same colour, sporting a near identical appearance, the only easy means of separating the two snakes being a distinct black spot on the neck of the male.

Both snakes were used for live reptile demonstrations, the male being used in almost all shows, including when pre-slough and from about November 2004, even after being fed (as in the same day).

While the dominant food item was mice (always dead and taken from freezer and thawed in warm water), these snakes were also fed chicken necks (average every five feeds) and occasionally other meat based items such as lumps of chicken, lumps of kangaroo meat, steak and the like.  All were taken voluntarily, in some cases having to be scented by placing a mouse leg over part of the item before it was held in front of the snake with giant tweezer tongs.

These snakes never gorged themselves on massive quantities of food as seen in the large heavy bodied elapids like Red-bellied Black Snakes (Pseudechis porphyriacus) or Tiger Snakes (Notechis scutatus) both of which would eat up to five times as much for a snake of similar length and averaged 3 times as much per feeding.  Partially in compensation, the brown snakes did feed with slightly greater frequency.

The average number of live demonstrations was about 3-5 days per week, with it being common for the snake/s to be used in more than one showing per day.

Within weeks of commencing use in these demonstrations (both snakes being used only after being made venomoid), both lost all inclination to try to strike or bite, indicating that the placid state was readily attainable for this species given the right conditions.

(Since end 2005, three more specimens of P. textilis (two from SA), all aggressive when acquired, subsequently made venomoid and routinely free handled become totally docile and tractable).

It became clear that the lack of confrontation with the snakes in terms of avoiding pinning and necking and hooking on a regular basis was a major factor leading them to become tractable and amenable to being handled.

In terms of other activities, feeding and mating and the like, none were in any way curtailed by the snakes as a result of the showing in public indicating that even with regular handling on a day-in day-out basis the snakes were not unduly stressed by it all.

In terms of this and all other reptiles used, the shown reptiles would within a short period (weeks to months) lose all evidence of being stressed from the showing and would eat if offered food (when evidently hungry) as soon as brought back to their home facility.

(Usually all snakes would be placed in their cages and fed from 1-2 hours later which enabled them to sit on their heat mats and attain maximum temperature, which generally correleates with being an appetite stimulant.

Snakes were generally not offered food when being shown, except if the booking person would ask for it.  This was generally only every few months and usually Tiger Snakes (Notechis scutatus) were used for this due to the fact that I had more of them (10 in total).

OTHER MANAGEMENT ISSUES

Because the primary purpose for holding these snakes was for live reptile demonstrations and I preferred to use the same snakes as often as possible (all the time), none were ever “rested” as such.  This isn’t as bad as it sounds for the snakes as in reality they spend most of the time on show days being moved about in resting position in boxes.  At the home facility the snakes would be similarly cramped under their hides anyway.

The main detriment in terms of being away from the home cages was in terms of the snakes being unable to bask as they please to warm up and digest food and the like. 

Snakes generally are kept cooler when being transported than they’d be when at home in their cages and basking.

When shows were more-or-less every other day or occupied only part of a day, the diurnal regime of heating and overnight cooling was not seriously impeded in any measurable way in terms of the snake’s welfare.  Obviously in winter, when there was no feeding, this was a non-issue. It should also be noted that in the real world, diurnal temperatures change from day to day in line with the weather and similar interruptions in my facility in terms of the shows did not seem to be a problem.

However at certain times in the spring/summer period, there would be periods of up to 30 days in a row where the same snakes would do shows.  In order to maintain a “normal” feeding regime the snakes had their 24 hour cycle reversed to equate the cage’s cool period with the daytime and basking at night.  The snakes readily adapted to the switch and the reversal as and when required.

On other occasions, heat mats would not be turned off overnight (the automated system overridden) to facilitate digestion of food before a next showing.

Feeding of all snakes was timed to coincide with gaps in the show schedule and snakes readily adapted to the schedules as imposed.

Because of the inherently high risk of importing mites during shows (via the “hands on” with pythons and other reptiles and in my case cross-handling these and all other snakes, including the P. textilis), the snakes would be sprayed (in their carrying box) with “Top of Descent” at the end of each day’s showing, to ensure no mites.

In spite of being sprayed a number of times each week, no snakes ever displayed adverse symptoms to exposure to the chemical. 

The amount of spray in the box was merely enough to enable it to be smelt, that being enough to kill the mites.

HOUSING

Adult Eastern brown snakes are not regarded as difficult to keep.  They usually feed readily (on rodents at least) and seem to do well in various types of cage set-up.

Notwithstanding this, simple cages are preferred due to ease of access to the snakes, cleaning and other day-to-day management issues.

As for most snakes, the essential requirements are heat gradient, clean drinking water and cover to hide under.

As anything else is superfluous, so the minimum is all my Eastern Brown Snakes got.

In my situation the basic cage is the same as that I use to house most of my elapids (and pythons).  As the majority are venomoid and readily free-handled for all management matters, safety is a non-issue and the cages are not designed with this in mind or in order to avoid bites.

But please note, bites are rarer with venomoid elapids than pythons! This is in spite of identical handling methods.

The snakes cages are in fact merely a plastic tub/s with air holes as vents. 

Dimensions are 57 cm long X 38 cm wide X 28 cm high and they are part of a rack system housing (shelves) for many other species of snakes as well, usually at one per “cage”.

This housing is deliberate as it has been found that snakes don’t like their own kind and do better when housed on their own in terms of feeding and general happiness, which reflects in a lower incidence of stress related ailments and those brought on by improper thermoregulation.

At the cool end of the cage is a water bowl that must be unspillable.  These are custom-made using a cast and with concrete as the material of construction (see Hoser 2004b for a detailed explanation of these).

As the snakes never go in the bowl, they only drink from it, you can get away with filling it almost to the top, without worrying about spillage or soiling.  This was standard practice as this reduced the need for “top-ups”, although these were generally done when snakes were removed for shows, fed, or cleaned.

The warm end of the “cage” is heated by a heat mat under the tub running to a temperature in the high twenties to high thirties (deg C.) depending in part on room temperature at the time.  Also see notes on temperature regulation below.

Midway in the tub is placed an upturned plastic pot that is sealed at the drainage holes and had a U-shaped "door" cut into the face down upper rim.

In mid 2005 the pots were jettisoned for cut up buckets acquired from construction sites and ice-cream shops.  Lacking holes in the bottom the buckets were easier to make suitable.  The plastic sections covering the holes in the pots tended to come off after time and this was averted by switching to cut buckets.

If needed, for safety reasons I had a handle on the top of the hide (base of pot), enabling this to be lifted by a hook if required.  However with the venomoid snakes (the ones subject of this paper), the need for a “handle” was superfluous and hence they were dispensed with due to the occasional defecation over them making them harder to clean.

The snake will hide in the “hide” and many soon learn to shift it back and forth over the heat mat to theromoregulate and remain hidden if it desired.

There is no doubt that in the wild state, thermoregulating while hidden is one of the optimal states for a snake.

As a substrate, newspaper is used.  However for newly acquired snakes this was not used for some months.  Instead I had no substrate.

This was deliberate as it forced the snake to use the upturned pot as a hide.  The snake cannot mess things up by burrowing under paper.

In other collections I see this problem all the time.

After some months and when the snake obviously is likely to remain trained to hide under the “hide”, newspaper may be used as a substrate, which makes cleaning the cage easier.

Anything extra in the cage is a waste of time and likely to be defecated on anyway, so why bother?

An issue of note in some elapids (mainly Tiger Snakes) is nose rubbing, which is more prevalent in that species than any other large Australian elapid.

This mainly occurs in large wild-caught adult males as they try to escape and move about the cage.

The obvious solution is to have a larger cage.

If however you have a rack-style system of plastic tubs (as I did), and don't want to up the size of the cage, a viable alternative is to use signwriter's sticky label to obscure the clear plastic or glass, save for a small flat area (away from corners) to see in and out of the cage.

This will tend to reduce the rubbing to a level sufficient to enable the problem to correct itself.

Obviously any serious snout injury may take some time to heal as in months and additional treatment with antibiotics or similar may be needed.

Snout-rubbing was never a problem in the P textilis subject of this paper, except once in the female that bred, which is somewhat surprising given the small sizes of the cage and the alleged activity of the species, especially when comparing them with Tiger Snakes of similar size that did in fact rub their noses.

That female stopped rubbing after the cage was altered as indicated above and the bleeding snout wound healed rapidly.  Betadine was applied three times after the rubbed section was detected, the wound healed and rubbing never occurred again.

Notable in the case of the female snake was that the snout rubbing incident occurred more than a year after the snake was acquired and it had never been kept in any other cage.

SHIPPING AND SNAKE SHOWS

When being shipped for showing to the public for reptile demonstrations the snakes would be moved in plastic containers called “click clacks” measuring 30 cm long X 20 cm wide X 10 cm high.  These also had air holes drilled in them with a soldering iron.

As a rule more than one snake would be placed in a given container to the maximum carrying capacity of the click-clack to the extent that the container could be filled so long as snakes were of size compatibility (of similar mass).  Which taxa was mixed with which didn’t matter as all were effectively non-venomous (pythons or venomoid elapids) and hence none had any means or inclination to attack or kill one another.

While on most nights between showing, snakes were placed back in their cages, this was not always the case.  When traveling in rural areas for events, snakes would either remain in their shipping boxes or be placed in a “group cage” essentially similar to the home cage, the only major difference being that numbers of snakes were together.  The main reason for this housing was to allow the snakes to drink if required.  Sometimes when shows ran late into one evening and were to start early the next morning snakes would often be left in their transport boxes or grouped into a few home cages to enable more rapid loading the next day.

The click-clacks used to ship the snakes were in turn placed in a large metallic box.  This worked well as a transport case, save for in hot weather, whereupon it would be lined with ice sheets (frozen towels in bags) to prevent overheating.

Experience showed that larger snakes (over a metre) tend to drink only every 2-3 days (at best) and hence there was generally no urgent requirement to give them a drink if overnighting at a venue.  Snakes that were clearly resting in their “click clacks” in evenings would be left “as is”, whereas restless ones would be transferred to a larger “cage’ (tub) overnight.  As a rule this meant most snakes, (including the P. textilis) would remain in click clacks for up to 48 hours (or occasionally 72 hours) except when removed briefly (for a few minutes) when doing live snake shows.

In terms of the home cages, the temperature regime was varied seasonally to enable breeding to take place.  It seems that the long-term seasonal temperature regime is most important in terms of initiating breeding (spermatogenesis and ovulation) and timing them correctly to successfully breed P. textilis and other large elapids.

PRE-BREEDING

In the winter of 2004 (mid year in Australia) most of the snakes being shown on a regular basis were not cooled down.  This related mainly to the fact that doing live reptile shows burns up the reptile’s energy levels far more rapidly than would otherwise be the case with a caged pet reptile.  It was uncertain if reptiles engaged in a grueling program of shows would be able to cope with a winter’s non-feeding as well as doing shows.  A number of snakes at the facility were also immature and hence breeding wasn’t a possibility and so those snakes were not cooled in any way.

Snakes not cooled in 2004 included the Red-bellied Black Snakes and most of the Tiger Snakes, most of whom were either immature or young adult.

Notwithstanding this, snakes that were cooled included the male Eastern Brown Snake, two male and two female Tiger Snakes, all of whom continued doing live shows throughout the winter period.

These snakes entered the overwintering period in fatter condition than their wild counterparts and as a result of their showing they emerged from the overwintering slightly thinner than their wild counterparts, but otherwise in good health.

Any lack of condition was rapidly regained when feeding recommenced.

BREEDING 2005

As a result of what occurred in 2004, it was decided to breed most of my elapids using methods that had proven successful for Death Adders (Acanthophis spp.) on numerous occasions in the 1980’s.

Snakes were “heated” for 12-18 hours a day until 17 May 2005.  At other times the snakes in their cages would drop to room temperature which was generally in the range of below 20 Deg C.

The building had an air conditioner thermostatically controlled meaning that in the hottest weather the room temperature never exceeded 30 Deg C.

No snakes were fed beyond end April 2005.  In the week preceding 17 May 2005, the number of hours of heating were dropped to about 6 hours a day.

On 17 May 2005, all breeding elapids, including the P. textilis were “flatlined” below 20 deg C.  Heatmats ran for four hours a day to about 18 Deg C. maximum which was generally warmer than the room temperature.

As a result the snakes would “bask” on these relatively cool heated spots for whatever warmth they could get.

On 26 June 2005, the “cool heat” was extended to 12 hours a day on.

On 5 July 2005 all elapids were put on 12 hours a day heating (heat mats at about 30 degrees C or higher) and a week later feeding commenced for all snakes with most accepting food within the first three weeks.  This included the P. textilis.

In the spring of 2005, the female P. textilis was voracious.  By contrast the male’s feeding was relatively sporadic until later in Spring (about October 2005).

On the morning of 1 November 2005 the male P. textilis was introduced to the female and mounted her immediately.  Connection was within 20 minutes. The snakes were seen separated the following morning and the male returned to his own cage.

At 3 PM on 6 November 2005, the male was introduced to the female and mounted her immediately.  Within 20 minutes the snakes were connected and they remained so until about 11 AM the next day.  At 8 AM on 7 November 2005 the two mating snakes were removed from their cage and placed on a natural background (a rock) where they were photographed.

The snakes were not upset by this and continued mating and remained in this position again as they were placed back in their cage.

The male mounted  and connected/copulated with the female again on 14 November 2005 (all day starting in the morning) and the following day was seen resting away from the female.

The female showed no signs of having eggs at this time and it was thought unlikely that she had sufficient condition to produce eggs.

Throughout November this snake’s feeding was particularly voracious and the snake went off her food from beginning December (no feeds that month until after laying eggs)

However on 8 December 2005, the date on which the female shed her skin, it became evident that the snake had developed eggs inside her and these seemed quite large and so showing this snake in demonstrations ceased.

The snake was from then on monitored closely in anticipation of egg-laying.

At 3 PM on 23 December 2005 one egg was noticed freshly laid in the cage with the snake’s vent immediately next to it, indicating it had been laid within a minute or two earlier. (This assertion was confirmed in hindsight based on the condition of the egg when first seen).

No egg-laying site had been provided and the snake had merely laid it under the upturned bucket (hide).  A second egg was laid at 3.15 PM and both were photographed at this point.

Immediately after this, it was noticed that the first egg had gone from being “normal” in appearance to being “shriveled” and so both were placed in an incubator.

The shriveled egg was sprayed at one end (half the egg) in order to rehydrate it and after some hours it appeared to have done so.

However the egg appeared unnaturally blotchy and was deemed unlikely to hatch.

The second egg appeared to be OK.

No more eggs were laid on this date.

The following day (24 December), another egg was laid at 10 AM “egg 3” and the others were laid at the following times:

4 – 10.30 AM

5 – 12 Noon

6 – 12.30 PM

7 – 1.00 PM

8 – 1.30 PM

9 – 1.50 PM

As the eggs were being laid, they had a papery white appearance and were somewhat translucent.

The eggs had clear polarity in them and when candled against a florescent tube were seen to be developed in as much as veins traversed the egg entirely and a tiny embryo was present at the top of each egg.  This view was present in the eggs at the time of being laid, even without candling.  One or more of these freshly laid eggs were photographed with the polarity being clearly visible.

Two of the eggs were laid in a manner that indicated “rolling” and they were actually turned about 90-180 degrees to re-align them.

Each egg had it’s number marked on it as laid with a red inked alcohol based marking pen, along with a line along the top median.  Each was placed in the incubator as soon as laid in order to avoid further dehydration mishaps as occurred with egg 1.

Within an hour or so of being laid the shells of the eggs thickened in appearance so that the previously obvious polarity was no longer noticeable unless the eggs were held and candled.

The tenth and final egg was held near the vent for some time and eventually laid at 3 PM the same day.  It was a different colour to the other eggs and did not appear to have the same obvious polarity of the other eggs.

At the time of oviposition (laying), I thought that the level of development in the eggs more-or-less equated with that seen after a week in eggs that are laid with little or no development before that point.  In hindsight the level of development may have equated with even more time.

Egg one declined in condition in that it became a yellowish colour and started to mould.  It was removed from the incubator on 5 January 2006 and sliced open.  The inside was hard and yellow and nothing detectable.  However at the top pole was found evidence of a tiny embryo including the beginning of the development of an eye.

Hence I concluded that the egg was fertile and had died as a result of rapid dehydration immediately after laying.

This fate did not occur to any of the other eggs, all of which were placed in the incubator immediately (within seconds) after being laid.

The female snake appeared to be perfectly healthy after laying the eggs and her movements indicated hunger.

On 25 December (the following day), the female snake was offered an unscented chicken neck which was taken immediately.  (This is the main food used in the Hoser collection of elapids and pythons).

This item was followed by an adult mouse, also taken.

On 28 December the female snake was offered a single mouse which was eaten immediately. 

On 31 December (3 days later) the female snake was offered three adult mice in succession, the first two of which were taken (third refused).

Later the same day the male P. textilis was placed with the female and he immediately mounted her. 

For three days (to 3 January 2006) the male remained on the female and was intensively trying to copulate with her.  Throughout this time the male’s tail was properly aligned, but at no stage was connection observed (in spite of regular checks involving moving the tails).

Hence it could be safely concluded that no copulation took place at this time.

The female continued to feed voraciously into January 2006.

My planned feeding and mating regime (just outlined) was done with a view to getting the female to double clutch for the same 2005/6 season.

(For the record, the same male was then removed from the cage with the female it was furiously attempting to mount and then placed in another cage with an adult female “P. textilis” from Adelaide and neither snake showed interest in one another, the Melbourne male P. textilis behaving as if the Adelaide specimen was a different species).

MEASUREMENTS OF EGGS WHEN LAID

All measurements are straight-line and at widest points

1 -  50 mm long, 21 mm wide

2 – 44 mm long, 22 mm wide

3 – 46 mm long, 22 mm wide

4 – 44 mm long, 22 mm wide

5 – 45 mm long, 22 mm wide

6 – 56 mm long, 22 mm wide

7 – 54 mm long, 22 mm wide

8 – 45 mm long, 22 mm wide

9 - 45 mm long, 22 mm wide

10 – 44 mm wide, 22 mm wide

Total weight (all ten eggs as a mass) 140.7 grams

MATING

Mating for the species is stereotypical as for other elapids.  The male mounts the female, aligns his body with hers and aligns the relevant section of the tail.  He then inserts his hemipenis into her vent.  This swells and the two snakes become effectively connected.

In the pre-connection period which may last anywhere between minutes and days (depending it seems on the female’s willingness to mate) the male will simultaneously twitch sections of the fore body and rear body more or less simultaneously.  This has been videotaped by myself.

Once connected this twitching declines in frequency.

The male will when mounting the female align his chin region sideways down the side of the female’s neck.

INCUBATION

Incubation of snake eggs is now routine for reptile keepers.

Almost all reptile eggs will hatch if incubated in sterile medium at high humidity (but not saturated) and at about 30 Degrees Celcius.

To that end, the Hoser incubator typified this regime.

It was a modified non-working fridge.  The engine had been removed to make it lighter and easily moved.  Holes were drilled through the sides with the wires running the various essential components running into the cavity.

Inside the fridge cavity was a small thermofilm heat mat at the bottom of the fridge and sitting on a wire cage about 1 cm off the fridge floor.

Heat mats are preferred to light bulbs as they are reliable in that they don’t “blow”.

Two computer fans placed strategically at the bottom (one facing across the bottom, the other facing up), and held with “bluetac” ensured an even distribution of air in all parts of the chamber.

A probe thermostat regulated the temperature by turning the heat mat and fans on and off as needed.

Set at 30 Deg C, this meant that the temperature inside the fridge actually oscillated between 28.5 and 30 deg C.

It never exceeded this because the room the fridge was in never exceeded this (due to thermostatically controlled air conditioning).

Inside the container/s used to hold the incubating eggs the thermal inertia was very good.

The temperature never went outside of 29.5-30 Deg C. except perhaps if and when the eggs were removed from the fridge to be inspected.  This was generally for a matter of seconds every day or two.

The insulation of the fridge gave the incubator good thermal inertia, the result being that the heat mat and fans would only be running for a fraction of the time in a day.

The eggs themselves were placed in a vermiculite media to a depth of 75% buried in nearly sealed plastic containers.

The vermiculite was mixed with water to an extent that it became clumpy but not wet.  It had been run through a rice strainer to remove the finer particles (when dry).

The humidity in the container was maintained at a level to enable condensation on most of the sides (or at least some), but not saturation and dripping from the top.

This enables a humidity of 100% or close to it and the eggs to remain fully hydrated, dry to touch and not wet. This is how the P. textilis eggs were incubated.

As a matter of note, all incubators, including this, should be tested before eggs are laid to ensure no mishaps.  This occurred with this one and in the 2004/5 season (the year before) it was used to successfully incubate Taipan (Oxyuranus scutellatus) and Carpet Snake (Morelia macdowelli) eggs.

(If in the unlikely event that humidity were to be too high through the vermiculite mix, then the container’s lid would be left off or part open.  If too dry the corners of the incubation medium can be sprayed to allow the moisture to disperse over time.  If the eggs themselves appear to be drying out, they can be sprayed directly (although this is best avoided, or only part spray an egg).  Preferable to spraying a slightly indented egg is to fan it with humid air, whereupon it should rehydrate as fanned.  Usually a container lid will suffice as a fan.  None of these contingencies occurred in this particular case, which was an uneventful incubation).

Also of note is that another Victorian snake breeder (Colin Ray) lost eggs in a similar incubator in 2005 when the thermostat malfunctioned.  Hence an improvement on the design would be the use of two thermostats in tandem, in case one of them malfunctions.

HATCHING

On 29 January 2006 the eggs were noticed hatching.

This process was typical as for other elapids.

The snakes were noticed to slit the shell and then poke their snouts out.  When I viewed the eggs, the snakes would retract inside the eggs.

All eggs were slit at or near the mid dorsal line and in most cases only once, from where the snakes ultimately emerged.

The first six eggs were noted as slit at 5 PM, with the seventh egg also slit within another 60 minutes.

The first snake was seen to leave an egg at 11 PM and it measured 26.5 cm.

All snakes had left the eggs by the following morning and recorded the following total lengths (measured on morning of 30 January 2006).

1 – 26.5 cm

2 – 27 cm

3 – 27.5 cm

4 – 27.5 cm

5 – 26.5 cm

6 – 28 cm

7 – 27.5 cm

(The numbers of young above, do not equate with the egg numbers).

In total the young measured 51.1 grams (average 7.3 grams).

Egg 9 was candled and looked questionable but was still definitely alive with red veins etc running through it and so it was left alone.

That snake hatched later (next day) and had an overshot lower jaw.

It was also a “runt”.

Thus the total hatch rate was 80 per cent.

However when one removes the infertile egg (ten) and the first egg to have been dehydrated at the time it was placed in the incubator, the hatch rate was actually 100 per cent.

Hence it can be reasonably inferred that the conditions provided were optimal, or near optimal for incubating this species and should be repeated by persons seeking high hatch rates.

The closeness of hatching (virtually simultaneous for the clutch) was a reflection of the thermal stability and inertia of the modified fridge incubator and is in effect an endorsement of this style of incubation versus other incubators which do not have as effective a means to evenly distribute heat within the chamber.

BREEDING OTHER SNAKES

In the breeding season of 2005/6 the same temperature regime (pre-breeding/cooling regime) was used for Red-bellied Black Snakes (Pseudechis porphyriacus), Sydney Death Adders (Acanthophis antarcticus) and Tiger Snakes (Notechis scutatus) with all producing live young.  All were venomoid.

In the previous year’s season, the same regime was used to successfully breed and incubate eggs from a pair of (Brisbane) Queensland Carpet Pythons (Morelia macdowelli) and to hatch eggs from a female Taipan (Oxyuranus scutellatus).

RAISING YOUNG

None of the young mentioned above have been raised and hence there is no data on them.

However neonates of P. textilis have been raised by myself previously and the general basics are covered here.

The type of housing is not important so long as the basics as outlined above are met.  Due to the small size of neonates small plastic containers with waterbowl, hide and placed partially over a heat mat are best.

Heating is best kept on 24 hours a day until at least subadult and while a temperature gradient is important, a warm room (minimum temp of over over 20 degrees C.) seems to be better for the snakes than a room with cooler background temperature.

This seems to be true for most smaller and growing young snakes.

It is hard to induce young Brown snakes to eat and if they do, it’ll usually be on skinks.  Unless frozen the skinks will carry parasites which in turn cause further problems down the track.  This includes up to several years down track!

Skinks are difficult to acquire in the numbers needed for even a few snakes.  Furthermore in some states it is illegal to use them as food.

As a result I find it best to pin then neck and force-feed young P. textilis until about 60 cm in length.  The food of choice is tiny mice, but due to cost considerations, I typically used drumsticks (legs) of small mice for neonates and larger rodent parts for larger snakes.

These I find superior to rodent tails for several reasons.

At first the snakes are reluctant to be force-fed and will often try to regurgitate their food.

As a result it is best to massage the food into the stomach of the snake.

The snake is best held straight as this is done.

Due to the delicate nature of the neck of the snakes, any sharp protruberances on the mouse limb should be either pulled or cut off.

The snakes should be fed smallish feeds but as often as possible within the constraints of how fast they digest their food.

Usually this enables feeding every 2-4 days and this regime should be maintained to enable maximum growth rate.

After several force-feedings the young snakes do become more amenable to being force-fed and so the need to massage food right into the stomach region reduces.  Eventually the snake will tolerate being assist-fed (that is food placed in mouth and it completes feeding itself).

In captivity a growth rate of from 3-5 cm a month should be attainable for any P. textilis to subadult (well over 60 cm) based on regular feeding and continued heating.  This is the standard growth rate I attained in NSW P. textilis young from Sydney and Orange (banded (Sydney)and unbanded (Orange) young.

P. textilis not fed as often or as much, simply fail to grow and also appear more susceptible to ailments.

Larger P. textilis (over 75 cm long) tend to feed readily on their own and this includes juveniles force-fed to this point.

As of end April 2006, all 8 young from the above Hoser breeding were alive and well.

SOUTH AUSTRALIAN P. TEXTILIS

The female from Adelaide SA, mentioned above had been acquired on 30 November 2005. 

It was housed alone and produced 14 unfertilized ova on 13 January 2006, of about 1/3 the mass of the fertile eggs produced by the Victorian snake subject of this paper.  All were discarded immediately.

The higher number of eggs produced may have something to do with this taxa and be a consistent relative difference between Adelaide and Melbourne “Pseudonaja textilis”.

Further investigations are required to determine if this is so.

(However on 7 December 2003 I received a call at Snakebusters from Heritage Country Club, Chirnside Park to remove a “Three foot Copperhead” in their gardens.  I went there and found a 143 cm (total length) Brown Snake (P. textilis) that was dead and had been bashed on the head with shovel.  It was a gravid female.  It had 13 third to half formed eggs inside her).

As to why the eggs from the Adelaide P. textilis were only one third size when passed, it can be speculated that this resulted either from them being unfertilized or perhaps another factor, including perhaps size/age of the female snake.

At the time the snake measured 90 cm (S-V) with a 21 cm tail (entire).

A male received from Adelaide at the same time measured 93 cm (S-V) with a 17 cm tail (entire).

It was not possible to “tail sex” these snakes, making probing the only alternative to accurately determine the snake’s sexes.  A similar situation is seen with P. textilis from other areas, with many males having tails of similar size and length to females.

In line with Victorian and NSW P. textilis, the male from Adelaide tended to be more highly strung than the female, which seems to be a trend difference in the sexes in P. textilis.

Both South Australian P. textilis were made venomoid on the evening of 6 Feb 2006, were offered a small (dead) mouse on 8 Feb 06 and ate readily.  Both snakes made uneventful recoveries from the operation. 

In terms of the unfertilized eggs being about 1/3 the size of those laid, this may have a connection with this size being the largest point at which fertilization can occur, after which it cannot be done.

Similar sized unfertilized ova were passed by a wild-caught female Tiger Snake (Notechis scutatus) held overnight in March 2006.

However for Death Adders (Acanthophis spp.)) and Red-bellied Black Snakes, unfertilized ova passed by females may be of the same size as fertilized eggs.  (Tiger Snakes, Red-bellied Black Snakes and Death Adders all give birth to live young).

DISCUSSION: THE EGG-LAYING SEQUENCE

In the wild state, P. textilis would presumably find a suitable egg-laying site, modify it as best it could if need be (as in perhaps moving about to create a so-called depression or chamber), and then when the time is “right” it’d lay the eggs.

In theory the egg-laying event would coincide with the completion of the first steps, or be shortly thereafter.

In captivity, it’d be rare for a perfect egg-laying site to be available (as occurred in the Hoser breeding) and hence the eggs would be deposited in the “best” spot in the cage.  In the Hoser breeding this was under the “hide” rather than in the open.

However this site would be far too dry for any chances of any eggs surviving any reasonable period (see for egg 1 above).

It has been noted by myself and others that captive reptiles unable to find suitable oviposition sites will hold onto their eggs beyond the usual laying time and then produce eggs which have already commenced early development.  This is indicated by partially developed young (evident via candling), that have effectively incubated inside the female.

Usually these eggs continue their development when incubated and hatch in the normal way,

It is assumed that retention of the eggs by the female beyond the preferred laying time did occur in the Hoser breeding.  This is because the two eggs laid on 23 December were apparently fertile and yet the female chose to hang onto the other eight eggs for another day.  This apparent holding onto the eggs for an extra day, did not adversely impinge on the overall development of the young, meaning that there must some degree of flexibility in terms of when the snakes lay their eggs.

A similar explanation may be in order for the Banks 1983 breeding’s, noting that eggs were also deposited in sites not amenable for long-term incubation.

However, other factors may be at play in terms of the relatively advanced state of the Hoser P. textilis eggs when laid.

That it is routine for partially developed eggs to be laid in P. textilis is also indicated in the manner by which the eggs were laid.

Eggs were never laid as a bunch, but rather one at a time with each single egg-laying spaced by intervals of several minutes and well after the eggs could begin to adhere to the ground surface beneath them.  The passing of the eggs was relatively slow (separated by at least 20 minutes for each egg) and somewhat controlled. 

This is in sharp contrast to how this species passes feces (they do this by raising the tail and literally squirting it out as best they can and with little regard for where it goes).

This would imply that it’d be routine for eggs of this species to have well-developed polarity at the time they are laid, even if laid in “normal” wild-state conditions.  The laying process presumably is designed to maintain the developed polarity beyond the time of oviposition.

(In December 2003 a Taipan (Oxyuranus scutellatus) passed 9 eggs at spaced intervals, however well developed polarity wasn’t noticed on these eggs at the time of laying).

DISCUSSION: COMPARISONS WITH PREVIOUS BREEDINGS BY OTHER KEEPERS

Due to the number of Eastern Brown Snakes caught by herpetologists, it stands to reason that gravid ones have been caught and the eggs hatched.

One such case was documented by Wells 1980.

In the context of this paper, the Wells 1980 results are largely irrelevant.

Captive breedings on the other hand are rare for the reasons already given.  The only other successful captive breedings documented in the literature were the cases at Royal Melbourne Zoo as detailed by Banks 1983 in which 5 clutches of eggs were hatched with varying degrees of success.

Besides some hatchings by Neil Charles in Brisbane, it is likely there have been no others.

The Melbourne Zoo snakes were held generally grouped in a public exhibit, or “off display” and while numerous matings were observed, these were apparently in the context of the snakes being housed together continually and not necessarily as a planned breeding program.

There is also confusion between mating attempts (as in male mounts female), and actual connection/copulation occurring and in terms of the Banks paper, no clear indication as to how often one or both occurred is given.  This is noted in the context of the cases above, where after oviposition by the female, the male mounted and tried very hard to copulate with the female, but never connected (got his end in).

It should also be noted that Melbourne zoo probably had no intention to breed the species as they are to all intents and purposes “worthless”.

The Banks paper does not give any information on the all-important factor of temperature regime, however this can be inferred based on the information given and knowledge of the Zoo’s facility.

It is presumed that the temperature regime more-or-less paralleled that of the outside (wild) in terms of annual peaks and troughs, however extremes would have been avoided.  Whether or not the snakes were heated over winter is not known and this aspect may have had a major impact on relative breeding success.

Likewise in terms of the keeping of both sexes together for long periods, which is in stark contrast to the method employed by myself and which is in line with most breeding programs in the post 2000 period.

Chris Banks, an experienced reptile keeper, noted the likely stress caused by cage cohabitants and it’s potential impact on breeding success.

It is also known that snake to snake interactions are generally stressful to them, especially the non-dominant one, even if no over agonistic behavior is observed in the form of combat or biting.  In most cases adverse reaction by one snake to another results in one snake merely resting in a place that may not be it’s preferred position in the cage.

This was in fact seen in early 2006, when two males of this species were sometimes placed in a cage together.

One outranked the other (the smaller long term captive outranked the larger snake), and this “order” was achieved without combat. The ranking was seen by the positions occupied by both snakes when they shared the same cage with the higher ranked snake getting the “better” position (see Hoser 2005b).

It is now known that separation of sexes, except at time of planned mating enhances the likelihood of the male wanting to mate the female. 

In the case of my male Brown snake, this is certainly true with it attempting to mate the female whenever it is placed in her cage!

(The same snake also mated with an adult female Collett’s Snake (Panacedechis colletti) in September 2005, but nothing came of the union.  It attempted to mate with male Tiger Snakes on other occasions that same month).

The observations of the Banks paper and other literature (not cited here) indicates that mating activity for P. textilis peaks in spring.  In terms of my own snakes, this was also true, noting that while the male would attempt to mate at other times of year, successful copulation (as in copulation actually occurring) tended to only occur in this period, this apparently being a function of willingness by the female.

A most notable feature of the Melbourne Zoo breedings was the high level of egg mortality at various stages.

One of the Melbourne Zoo clutches was found in a severely dehydrated state in the snake’s cage and none hatched.  Based on my own experience with egg 1, it appears that eggs laid in suboptimal (for eggs) cage conditions will dry extremely rapidly.  This is true even if eggs are found within an hour of being laid, in which case a fertile egg could already be fatally disabled.

The Melbourne Zoo results also indicated numerous apparently fertile eggs that either did not hatch or were otherwise deformed.

The causes of these results are harder to guess, however I don’t believe that incubation temperatures were the problem, which was initially speculated by Banks.  (They used 30-31 Deg C) which based on a further 20 years of collective experience seems perfectly OK for Australian elapid eggs.

However what is a likely problem that may not have been anticipated by the Melbourne Zoo people was the well developed polarity of the eggs at the time they were laid.

When the eggs were laid by my own female P. textilis, it was noticed that as they were laid they tended to adhere to the newspaper substrate as laid and retaining their polarity as laid.  Only two of ten eggs actually rolled.  In the wild situation with eggs being laid in a chamber of correct humidity this may well translate as an 80% hatch rate based on the assumptions that rolled eggs don’t hatch and most eggs don’t roll as they come out of the vent.

Eggs of other snakes may not have the same polarity development at the time of laying and hence it may not be as important to maintain this the moment the eggs are laid.

In other words, for captive P. textilis about to lay eggs the following should be done to maximize hatching rates:

1 - The cage environment should be of high humidity (100%) so that newly laid eggs do not dehydrate before discovery.  One should not hope that the female snake chooses to lay eggs in a single designated laying spot.

2 – Eggs laid should be recovered as fast as possible and placed in a proper incubator, with each egg being candled for polarity (if the polarity cannot otherwise be determined) and the embryo to be aligned at the top (top pole) if it isn’t and/or was rolled when laid.

When breeding Death Adders (Acanthophis spp.) in 2002/3, three females passed malformed and premature, stillborn young.  The main deformities related to kinked spines and deformed heads.  All female snakes had been treated for a reovirus (known generally as Weigel’s curse) with the drug Enroflaxin (sold as Baytril)(see Hoser 2005).  The drug is known to cause birth defects in offspring of warm blooded animals treated with it.

It is unknown if any of the Melbourne Zoo P. textilis females received any teratogenic drugs prior to breeding, although one assumes this is unlikely.

While Royal Melbourne Zoo has an impressive track record in terms of keeping and breeding reptiles, the results given by Banks 1983 should be taken in the context of preferred keeping methods at the time as well as the constraints of holding the snakes in a public display, both of which contributed to the results seen.

Bank’s paper does however give sufficient information in order to see (in hindsight) the primary reasons for failure in breedings and hatchings as they occurred and in the light of what has become evident in the recent Hoser breedings gives pointers as to the potential pitfalls if attempting to breed this species and related taxa.

As it happens it is often more important to publish failures than successes and to that extent the publication of Banks 1983 sheds considerable light on idiosyncrasies when dealing with breeding P. textilis, especially when related to more recent experiences.

SUMMARY

P. textilis is easy to maintain in captivity, provided the basic requirements of the snake are met.  It is alert, somewhat nervous and intelligent.  In the first instance this translates as aggression to humans, but this can be tamed to enable the snakes to become tractable and non-aggressive captives.

This paper documented the first successful breeding of venomoid snakes in Australia, that being the 2005/6 season and proves that the venomoid state is of no impediment in terms of a captive snake’s long-term welfare or breeding potential.

As already mentioned, live-bearing venomoids (Tiger, Death Adder and Red-bellied Black) were also mated and bred by the author in the 2005/6 season.

Using methods similar for most of the common Australian pythons and elapids (viz overwinter cooling), and separation of sexes prior to mating, P. textilis is easy to breed in captivity.

High failure rates for eggs laid can be avoided by the following:

1.       Ensuring high humidity in the cage prior to oviposition.

2.       Removal of eggs from the cage as soon as possible, preferably as they are laid.

3.       Checking polarity of all eggs laid and ensuring they are aligned correctly when incubated. Rotate if necessary to maintain polarity when positioning in the incubator.

4.       Using a thermally inert incubator at about 28-30 Deg C, with eggs placed in a sterile medium at high (but not supersaturated) humidity.

ACKNOWLEDGEMENTS

Chris Banks (Melbourne Zoo) provided access to his records at short notice.  Numerous other herpetologists (not named here) who have freely shared their knowledge, experiences and opinions, all of whom have helped shaped the methods of keeping detailed here and also used by others.  The wildlife authorities of NSW, Victoria and South Australia provided relevant keeping and movement permits in a timely manner that did not impede the keeping and research of these snakes.

REFERENCES

Banks, C. 1983. Reproduction in two species of captive snakes, Genus Pseudonaja. Herpetological Review 14(3):77-79.

Hoser, R. T. 1989. Australian Reptiles and Frogs. Pierson and Co., Mosman, NSW, 2088, Australia: 238 pp.

Hoser, R. T. 2002. 'A new subspecies of elapid (Serpentes: Elapidae) from New Guinea', Boydii - Journal of the Herpetological Society of Queensland, Oct 2002.

Hoser, R. T. 2003. A new species of elapid (Serpentes:Elapidae) from Western New South Wales. Crocodilian - Journal of the Victorian Association of Amateur Herpetologists 4(2):19-26.

Hoser, R. T. 2004a. Surgical Removal of Venom Glands in Australian Elapid Snakes: The creation of venomoids. Herptile 29(1):37-52.

Hoser, R. T. 2004b. A new solution to a series of old problems ... the best water containers yet for snake cages. Litteratura Serpentium 24(3):104-111.

Hoser, R. T. 2005a. An avoidable epidemic of reovirus in collections of Australian snakes and the wider implications of the disease in Australia and elsewhere. Herptile 29(3): 94-106, 29(4): 162-169 and 30(1): 19-28 (Sept, Dec 2004 and March 2005).

Hoser, R. T. 2005b. Pecking orders in large venomous snakes from South-east Australia ... ecological and distributional implicatations. Boydii (Spring 2005):33-38.

Wells, R. 1980. Eggs and young of Pseudonaja textilis textilis. Herpetofauna  12(1)::30-32.

Two photos published with this paper – one of snakes mating and another of eggs hatching.

Below: World First!!! Successful breeding of venomoid Eastern Brown Snakes (Pseudonaja textilis). Unfortunately the hatchlings depicted were still venomous. See the 2006 paper on breeding Eastern Brown Snakes on the web at: http://www.smuggled.com/EasBro1.htm by Raymond Hoser, for the details of this significant event.