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My Woma just laid 6 huge eggs. I am letting her incubate the eggs. Do female Womas create their own temperature for incubation of the eggs?

Excellant question. I would think not, as they lay their eggs in burrows, and are rather primitive as a species, but I could be wrong. Yeah, they ARE large

Thank you for your response. By your way of thinking, then the Black-headed Python would also be non-heat producing during incubation.

Yes. Then again, I can't find any info on Aspidites. The new Australian Pythons book by Mike Swan has no info on that group, as far as maternal incubation is concerned. All Morelia do, as do Liasis. Maybe someone else has personal observations. I incubate my Womas in an incubator.

Do female Womas produce heat for egg incubation? After searching for the answer and not really getting anywhere, I have quite definite proof that Womas do not produce heat for their egg incubation. I hope that you do not mind having to read this but I found this experience quite interesting.

I returned on Father's Day from a four day trip and found that both of my female Womas laid six eggs each. One had them scattered into two piles and they were quite stuck together, so I knew that there was no way the she could get them together to incubate them. The second clutch was being incubated by the female so I decided to leave her alone. My inquisitive mind wanted to compare maternal to artificial incubation. Steve of Boamorph.com has a fantastic article on incubation of Woma eggs and I quickly got my incubator set up according to his article and there the first batch sits now at 31.5 degrees C. I have two tubs of water in the incubator and I am thinking of spraying the entire inside to help with the humidity.

The real interesting part is the maternal incubation. This is my first experience with Woma eggs as I am used to hatching Green Tree Pythons eggs. I fully expected the female to produce the heat necessary to incubate her eggs. Using two Herpstat ND thermostats, I placed one probe in the incubation box, right in-between the eggs and the other outside the nesting box. I set the cage temp at 87 degrees F. I noted that the incubation temperature was lower or equal to the cage temperature but never higher. I thought that as odd. The next day I became alarmed when the female left her eggs. I quickly readied another box for the incubator and when I returned to the cage she had gone back to the eggs. Much to my relief. The next day, I was present when she left the nesting box again and I saw that she headed directly to the overhead heating panel and tried to wedge herself between the panel and the top of the cage. Soon she went back to the eggs. She did that again the same day when I decided that she was not thermo regulating with her own heat production. I had purchased two warming plates from the thrift store (at $3.00 each). One was 100 watts and the other 110 watts. I connected the 100 watt one to a rheostat and placed it in the cage. I used my hand to sense the temperature and I set it to what I will call a high warm. As if she understood exactly what was going on, she left the incubation box just as I finished and she headed directly for the warming plate and she stayed on top of it and went to no other part of the cage for about 20 minutes. She went directly back to her eggs. The temperature of the eggs went from about 87 to 92.1 degrees F. There is no doubt in my mind that she left her eggs to seek heat for them

Here is a picture showing the female on the heat panel to absorb heat to take back to her eggs.

No...Womas, Nor Black Heads...... thermal regulate.

Cheers,
D.

Evidently that's what you get being on the lower end of the evolutionary chain, lol. I would assume, being burrowers, they simply find a spot underground that suits the temperature they require, then lay them.

Off the subject...Are u "the" derek roddy? As in drummer derek roddy? Just curious.

LOL!!!! Yea, its him "the" one and only!

Haha...to much Tom! Haha.

D.

Nah not around here. Here he is "The" "Black Head breeding Derek Roddy" much cooler than some guy that sits there and hits things with sticks.

Jason

Blackheaded pythons have been observed physiologically thermoregulating through muscular contractions on a few occasions. It was either Neil Charles or Richard Shine, but they maintained a few wild caught adults many years ago that bred and produced eggs. The females were seen to maintain a steady muscular contraction rate, but not nearly as regular or temperature controlling as P. molurus or other more efficient thermoregulating species. I have not seen any data on Woma's, but if Blackheaded pythons can, it would not be a big jump to find out that Woma's have the ability as well.

The behavioral thermoregulation, or basking, that you are seeing is most common with the smaller python species as they don't have the body mass to be able to afford to expend the energy required for true physiological thermoregulation. Aspidites and Morelia are medium size python species and they have a slightly different strategy than the larger thermoregulating species that can afford to expend the energy required for true, full time thermoregulation. These medium size species will use the much energy cheaper behavioral thermoregulation when at all possible before having to resort to the much more energy expensive physiological thermoregulation. This is why you rarely see these species actively thermoregulate by muscular contraction in captivity because keepers control the ambient temp 24/7 and keep it close to the preferred incubation temp. If the cage temp never falls below the mid-80's, these species will not need to physiologically thermoregulate and can usually easily get by with behavioral thermoregulation, or in cases where the temps are in the mid to upper 80's, no thermoregulation at all.

These species would only use physiological thermoregulation in the wild when the temps became too low in the evening and could no longer be compensated for by basking. This switch is limited however, and if the temps get too low, usually by early morning, they shut down altogether and let the egg mass temp drop somewhat. When the sun comes up, they bask again and start the cycle over. The use of burrows by these species gives an obvious insulating effect and helps buffer the low temps at night more effectively. If your cage cooled down enough, you might see the female start up contractions, but I don’t know at what temperature this might be triggered.

Your observations are excellent and show true natural behavior with this species. It also shows that most python species probably naturally incubate their eggs at higher temps than most people think. This is further proven by the fact that for many python species, with a few exceptions, incubation temps below 85 or 86 degrees can cause developmental problems and most do quite well and hatch within maternally incubated timeframes when artificially incubated at 89 to 92 degrees.

Kelly

Thank you for a great explanation. I do question your statement about the size as my Green Tree Pythons are thinner than my Womas and they thermo-regulate.

They other truly fascinating observation to me is the range of temperature that the females tolerate for their eggs. The Woma is going from 84 to 92. Both this Woma and the GTP have this wide range tolerance. Yet, when we artificially incubate, we are so picky about maintaining a certain temp through-out.

it appears that GTP’s thermoregulatory capabilities are more limited compared to the larger species as their ability to compensate for wide temp fluctuations has been shown to be less than that of the other large species. Their propensity to nest in hollow trees appears to be a further adaptation to temp conservation. GTP's also seem to have a lower average maternal incubation temp than most other pythons. You are correct in that the ability of the eggs in these species to tolerate the wide swings in temp are an adaptation to the limited thermoregulatory capabilities of these species.

Kelly

About 20 minutes ago she came out again looking for heat and I offered her a freshly killed mouse. She ate it. Now I know that she will eat and I will try to maintain some weight for her throughout this incubation.

A lot of people confuse "shiver protection" with thermal regulating....it's not.
Black Heads and Woma are very sensitive when it comes to egg protection.
I've been fooled as well....thinking that they are thermal regulating but, even vibrations can trigger a black Head to "hug" their eggs...this looks a lot like shivering.
I've noticed thermal regulation with all of my Carpets....not once with the BHPs or Womas. And, I've had a few clutches now. Haha.

Cheers,
D.

Having had the good fortune to travel to both Queensland and Alice Springs in Australia, I can tell you that in winter (our summer), it gets much colder at night in the areas that Woams inhabit as opposed to BH's, which is further north. Remember that north in OZ is warmer, south is colder. That black head is very useful for warming up, incubating or not. As has been noted in a lot of literature, the Southern Woma is usually much darker than it's northern relatives. That said, that's an interesting and nicely post, Kelly. Very informative. Even the people living in OZ are still learning about their own animals.

the contractions observed were cyclic in nature and non-random. I questioned it myself, but have heard of a few other instances over the years. I would like to see additional data on this as well. My guess is female BHP or Womas probably would never show this behavior unless the ambient cage temps are dropped into the low 80's or even upper 70's. I believe they would behaviorally thermoregulate above those temps. I don't know of any keepers anywhere that have actually dropped temps and tried this with maternally incubating Aspidites. It definitely would never be observed if the eggs are pulled for artificial incubation shortly after being laid. It likely would not be cool enough to initiate it in that short of time period. It would be interesting to see a maternally incubating female cycled through a large natural day and night temp fluctuation and monitor her behavior.

Kelly

I drop my female down like that.....down to the mid 70's and never seen it.
I always pull the eggs but, as long as you don't wash the female or the egg container.....the female will continue to "incubate" the "eggs"....full term...to the day.
After day 65....their whole program changes.

I've done many experiments with Aspidities based around learning their incubation habits because, I'm very interested in this function of snakes.
My room is an ambient 74 degrees all the time.
During the day...the cage has heat in form of a panel or light, and the cage will get 88.
At night....everything goes off in the adult cages and the temps drop to 74 or so.
I do this to imitate natural environment fluctuation.....even at those temps....down to the low 70's sometimes....and, they don't thermal regulate.
My carpets will thermal regulate at 88 degrees.Haha.
I've even watched BHPs females.... stay off the eggs for a few days and return to "protecting" them.
Like I said...they can fool you though.
Also, a friend of mine in Australia has watch wild females lay and leave the eggs (like a corn snake) only to come back to "check" in on them later. She never left the area and she only sat on them about 20% of the time.
Black Head are wild animals. Haha.

Cheers,
D.

Sorry...meant to say Females...plural...in that first line of my last post......as I've done this with all of my female BHPs.

Cheers,
D.

would be to leave the eggs with a female through the entire incubation period and continue the large fluctuation of the day-night temp cycle as you are doing. I have been using maternal incubation almost exclusively with several python species over the last 30 years and have learned quite a bit about this behavior. The P. molurus complex are the most intense and temperature controlling of all thermoregulating python species. Yet when their eggs are pulled, they will usually continue to physiologically thermoregulate through muscular contractions for many days if you do not intervene. However, they still do not maintain the characteristic, very cyclic contractions, or have near the elevated body temp as when they are on an actual egg mass. As such, it is possible your female BHP were not into the full scale maternal incubation mode and would not have been exhibiting their full maternal behavior or instinct as they might on an actual egg mass. It sounds like the jury may still be out on Aspidites as far as their ability to physiologically thermoregulate. No one I am aware of has done it, but it would be a great research project to leave eggs with several female BHP under simulated natural conditions and fully determine the extent of their capabilities. Great discussion.

Kelly

Has anyone else seen the shivering being done BEFORE laying? I've seen it in my carpets.

As far as my Woma is concerned, there is no shivering at all. All the heat appears to be from the hot pad . As I stated before, the temperature fluctuates a lot. But I am surprised that at the high point, she gets them into the low 90's. I have the incubated ones set at 88.5.

take some temps, and then you will see that they can in fact raise the temp by a degree or two...

I allowed my female to incubate her eggs last year and she routinely upped the temps at night when things cooled off by at least 2 degrees. Eggs hatched fine although I lost one baby that was at the center of the clutch and unable to pierce through the two egg shells that were glued toghether...

ciao
Lat

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Cheers
Lateralis
"I would rather be precisely wrong than approximately right"
Marion "Doc" Ford

Considering where they live, and the daily temp changes, I'm not sure a degree or two would make much of a difference.

The eggs don't have to be there to get MI information Kelly. They still think they are there and that's all that matters. As long as the snake still thinks she has eggs.....she will "incubate" them.

I too have done MI on a number of species and I've taken the eggs from the females and watched the very same behavior....with a number of species.

Again, I've watched all my females go through the "MI process" without the eggs even there.....and they don't not shiver....even when the temps are down to the low 70's. All the other animals I have...such as Carpets, etc... DO.
The BHPs and Woma....do not.

They do come out to bask, eat, defecate, etc.... and they will sit under the heat for a few hours to return to the eggs....BUT, they do not shiver once they go back.

I've been working with them for many years now.....maybe if you're that interested in them.....pick up a pair and see for yourself.
All I can tell you.... is the experience of keeping them and breeding them....for a good many years now.
Plus, I'm very good friends with 2 of the leading BHP researchers in Aussie.....neither one of them has made any notes about them Thermal regulating....and both these guys have 100's of hours in field research with them.
More than anybody to date.

Hell, you still hear people saying that Womas and BHPs don't have heat pits.....they do.
It was proven a few years ago....yet.....people still regurgitate the old info.

It was also discovered that they have venom glads.

Cheers,
D.

Also, I should mention.... There is a breeder in Aussie that does use MI on all his BHPs.....he hatched 13 clutches last year (he has over 50 adults!!!) He hasn't seen it....in the 10 years he's been breeding them.

1000's of hours working with the animal....gives you all the answers.

Cheers,
D.

I would definitely agree with you after you made this last statement about the Australian breeder that uses MI exclusively with BHPs. Like to have heard about that data earlier in the discussion. However, it would be nice to rule out physiological thermoregulation without muscular contraction, as some python species are capabile of. Easy enough to rule that one out. Are these guys that are using MI with Aspidites taking intracoil temps during the incubation period, especially at night? A small steady drop in intracoil temps over night would prove it decisively, whether "shivering" was observed or not.

Kelly

They definitely can raise the temp a few degrees with basking. They also urinate around the area to raise humidity.
I'll ask Denver with a little more detail... next time I speak with him.

On a side note....one time I put a pile of golf balls in with a carpet,I had just taken eggs from.....she "incubated" them. Haha.
Shivered...the whole nine. On day 56....(the day they hatched in the incubator) she crawled away.

Crazy....these snakes are.
Haha.

D.

"On a side note....one time I put a pile of golf balls in with a carpet,I had just taken eggs from.....she "incubated" them. Haha"

Would that be par for the course?.......

Haha...sure would.

D.

Basking is behavioral thermoregulation and is common of many snake species. Heat generated by muscular contraction is physiological thermoregulation. However, females of some python species physiologically thermoregulate by going into facultative endothermy and raise the egg mass temperature without using any visible muscular contractions. Retics are the most notable for this type of behavior. That is why it would be critical to rule out this type of behavior with BHP's by monitoring night temps with an incubating female. If she is just using behavioral thermoregulation, the temp of the egg mass will fall slowly throughout the night and will not rise again until she is able to bask in the morning again and radiate the heat back into the egg mass. It is unlikely that a snake with a body mass as small as a BHP would be capable of this type of physiological thermoregulation, but it would be nice to check on it anyway.

Kelly