Though work and the other parts of my life have kept me from updating this blog on a regular basis, working with the Gilas has not slowed down. As of today my females are gravid and have gone through their pre egg-laying shed so oviposition is expected within the next week, according to my calculations.
This year my nesting protocol has changed due to the failures (or, opportunities for learning) of last year. last year one of my females delayed egg laying by about 10 days which resulted in the death of six viable eggs. Not a very fun lesson but certainly an opportunity for improvement. I think last year the female did not have the proper secure nesting area and held her eggs until she could not hold them any longer. I also tried a new nesting material which did not work out very well as it did not hold moisture for very long. This year, things have changed.
To help increase privacy and to solve the humidity issue everything has been changed. To start, the entire cage has been converted to a nest box. This is to allow the females to continue to thermoregulate (though over lower temperatures) throughout this period. I have installed privacy tint on 1/2 of the cage as well as a large black hiding box to increase privacy. I also went back to good old sphagnum moss misted daily to help maintain moisture in the cage. The ultimate goal is to provide a secure area that matches conditions for positive egg growth. So far it appears to be working as the conditions in the cage mirror those in my incubator (see below screenshot from my SensorPush app).
Will this ultimately work? We will know within two weeks. If all goes well my females will lay viable eggs this year. If not, I’m sure there will be a lesson learned and opportunity for improvement next year! Fingers crossed!
With the babies I’ve held back are growing like weeds and coloring up beautifully, I’ve taken the adults out of brumation and am warming them up and will be feeding them their first meal soon. I’m both excited and nervous as to how this season will turn out. Will all the eggs paid be fertile? Will all the fertile eggs go to term? An educated guess says no to both but if improvements are made I am moving in the right direction.
I’ll be doing some new things this year. First, I’ll be pairing straight reticulated with reticulated, and banded with banded. Also, instead of leaving switching males between cages I will keep one male with one female for the duration of the breeding season. The females do seem to have preferences, and hopefully they still lie each other this year. I am waiting until the last week of March to start pairing as last year the females were not receptive and often attacked and bit the unrelenting males so it would be nice to avoid this drama and potential injury. I’ll keep everyone posted on the progress and of any successes and failures on my second year of breeding these amazing Gila monsters!
So, almost after all hope was lost on Day 153 the first Gila monster egg pipped from its leathery shell! Egg 02 at first cut a small slit and then a few more and over the next two days began to emerge from the egg. At first the baby Gila stuck its nose out, then it’s head, then half its body, and finally the entire body. It appears that hatching is a labor-intensive process as there are long pauses between progressive stages and also seems to be a good way of ensuring all the contents of the egg are consumed before leaving the egg. Over the ensuing days this process was (and currently is for two more lizards) repeated over and over, with Gilas emerging from their shell about two or so full days from pip to full emergence. Once the contents are completely devoured the neonate Gila monster leaves its shell and begins to wander the egg box. I witnessed one Gila that was out actually eating the egg yolk of another just coming out of its shell! Greedy bastard.
Once fully emerged and climbing around, the little monsters are pulled from the egg box, photographed, weighed, and set up solo in an 18 quart Sterelite box with paper towels as bedding and small water dish. The paper towel bedding serves as a clean substrate while the umbilical wound heals and the first few meals are eaten and passed through to make sure everything is going well. I will attempt the first feeding next week after the yolk has been fully digested and look forward to raising the babies from there!
I will be posting updates on the neonates growth, as well as some thoughts and insights on my first season captive breeding Gila monsters. Some reviews of the equipment I used is also likely in order as these items played an important role in my success. Whew, what an amazing season! The process has been fun, though frustrating and worrisome at times, and I look forward to greater success next year with these amazing reptiles!
Patience. Patience is what those in the know say. Sure, I am checking the incubator at least ten times a day for any action and patience is not my virtue, but I am old enough to know when to listen. A couple a the eggs dented in over two weeks ago, the two others are starting to dimple (not dent) and in all honesty I would be surprised if any of them hatch at this point. If they do not hatch my biggest concern is figuring out where my failure was. Is it the incubator? No, the Grumbach’s are renowned for their reliability. Is it the S.I.M. egg container? No, these have been used successfully with Gila monsters before. My temperature, though low, should not be the issue and my humidity is spot on, so it shouldn’t be that. We just started having cold fronts move through and temps have fallen so that may have a slight play into it (I have ordered a space heater to remedy this issue). At this point my guess is that since the fan in the Grumbach is unplugged that there may not be enough airflow which may be an issue, or the fact that the Pangea Hatch medium has started to grow mold adds to this theory. I do open the incubator to allow fresh air to enter but it may not be enough. Whatever the case, I will hold on hope until the last egg turns yellow and starts to sweat. If they all die I will carefully review my protocols and notes and seek the advise of successful breeders to plan for a better year next season!
On another note, I have stopped feeding my adults and am turning off the lights and under-cage heating in preparation of hibernation, which will begin after Thanksgiving. I have an old refrigerator that is hooked up to a Ranco thermostat for the cool down. Would be great if I could cool them in their cages but we do not see steady enough low temps here in northern Florida to ensure the Gila will reach and stay at 53°F for the three months of brumation.
We are 132 days past oviposition and the remaining six eggs appear to be hanging in there. One of the eggs has dented in, which I am hoping means that it will hatch in the next few weeks and does not mean the embryo has died. The other eggs remain rigid and appear to be well, fingers crossed they come to term! The Grumbach has been great in maintaining the temperature and humidity stable throughout incubation, but I have noticed that the egg boxes have increased in temperature by 1°F higher than the incubator over the last few weeks. Condensation has also started to build up (mostly on the sides) so I’ve been keeping an eye on that to ensure none falls on the eggs potentially suffocating the embryo inside. Since the eggs were incubated at the lower end of the range it can be expected that the eggs will hatch (if they do) toward the later end of the spectrum, potentially 150+ days. Man, I can’t wait…
On the other side of the house my adult Gilas are getting ready for next year. Weekly feedings of 2-3 mice (2 for the males, 3 for the females) has brought all of the Gilas to a healthy state; good fat reserves in the tails and a constant, though not concerning, weight gain. As most of my group was purchased earlier in 2019 and after the hibernation cycle, I do not have data on what the pre-hibernation weights were last year but I think they are ahead as their weights are above pre-breeding numbers from this season. I hope to have more fertile eggs that make it to term in the upcoming season as they entire group will have been with me for the whole cycle.
Winter cooling is going to start in late November and this year a larger refrigerator / cooler is going to be purchased in order to facilitate all adults. I’ve noticed an increase in activity and feeding response in the adults over the past week, almost being as active as breeding season. I do not know if this has to do with growing follicles and testes, a reduced photoperiod, or slight drop in temperature (or maybe all) but it does seem that the Gilas are getting ready for a long winter’s nap!
That’s all for now, hopefully the next post is of the Gilas hatching!!
Not much has happened since the last update; one good egg died leaving me eight healthy growing eggs in the Grumbach incubator. A universal agreement on Gila monster eggs is to leave them the F* alone during the long incubation time. I have a hard time doing this but have been a good bean and done so by only check through the incubator’s clear door and light to make sure none are dying. The Grumbach is holding temps and humidity as it should; Temperature ranges from 77.5˚F to 79.5˚F and humidity in the incubator stays at a steady ±90% RH (relative humidity) with the Squamata Concepts S.I.M. egg boxes at 100% RH. I have three SensorPush sensors (one in each egg box, one in the incubator) connected to a SensorPush Gateway to monitor temperature and humidity. And the Gilas? All are eating and back to normal, with the females gaining weight nicely. I still find it interesting how the feeding habits changed so much during the breeding season and look forward to more data next year from this interring period of time.
I wanted to post a few photos of good eggs and bad / dead eggs (see above) and discuss a few observations. When an egg goes bad, there is no mistaking it; they begin to sweat, discolor, and smell awfully. The good eggs remain turgid and whitish in color, with increasing veining (last I checked a few weeks ago) when candled. I do not plan to open the incubator door again unless something is going wrong or an egg dies, so hopefully they are growing and not just looking good….
My next post will be one on the tools being used in my program for Gila monster breeding and incubation.
Gila monster 06, formerly known as Joy, was thought to be a female and was the one that was sick. Now that Joy is better, I wanted to finally determine confirm her sex (though based on head size I guessed female). My intention was not to breed, only to watch the reaction and once I put Joy in the cage with a known male (one from the group she came from) Joy went right into battle mode and started wrestling with the other male. There went that theory. The girl formerly known as Joy is now a boy named Floyd. No more gender dysphoria. You be you, Floyd.
My first encounter with this behavior was many years ago when my best friend saw the Gila monster in its cage upside down and unmoving. He called in a panic and said that my pink lizard (his reference of Gila monsters to this day) was dead. Of course when the cage was opened the lizard sprang to life and was quite aggressive upon examination. Now that I have a group of Gilas, I see this behavior often. Above are a few examples of what this looks like.
I wonder why Gila monsters do this. Is it to thermoregulate different parts of the body? Does it aid in digestion? Maybe its like having restless leg syndrome and they just can’t get comfortable! This behavior is bizarre, but I must say that Gila monsters are quite interesting and they do some funny things I have not seen other reptiles do. I think a book on captive behavior alone would be a fun read!
After keeping Gila monsters for over twenty years and having a lifelong fascination with these amazing reptiles, my first earnest attempt at breeding them has been quite fun. Don’t know how successful at this point, but it’s the journey and not the destination in my case (though seeing baby monsters pip out of the egg would be a dream come true for me).
When studying up on breeding all these years there were so many questions I had. Can you tell a male from female by head shape or appearance? Why do you need a group or colony to breed? What does male combat look like versus male to female interactions? Is it better to keep them singly or in a group when attempting to breed? So far, I have learned a better understanding of these questions and will make an attempt at answering them to the best of my knowledge at this point.
To establish a base point, and long before this breeding season, I have collected as many books on Heloderma as I could (not to mention art, toys, and other chachkies). In relation to breeding, a few books have been the guiding light to my program. First and foremost is Dr. Mark Seward’s Gila Monster Propagation. Despite being one hell of a nice guy that has answered my random emails and questions for over 20 years, his book remains to be the most thorough and introspective writing on the subject. The focus on applying the natural process of wild Gilas to captive breeding is the obvious key to success, and the one I am closely following now. Amazingly, a PDF version of the book is free on Mark Seward’s website here. Of course I’m a dork and have the first and second edition in print:) The other book I am using is a European text, called Beaded Lizards & Gila Monsters Captive Care & Husbandry by Bernd Eidenmüller and Manfred Reisinger. This is another great book that offers insight and some different perspectives into breeding and maintaining Heloderma. I’ve never heard of a Grumbach incubator before reading this book, and liked what I read about the stability of the incubator so I picked up a used one off eBay (Compact S84), tested, modified, and tested again to get the temperature and humidity right. Fingers crossed I get viable eggs to go in this wonderful machine! The other book I am utilizing right now is the venerable Biology of Gila Monsters and Beaded Lizards by Daniel Beck. There is not a specific focus on captive breeding but it does provide invaluable reference to the natural biology and behavior of Gila monsters that can be applied to breeding and has given me a lot of thought on what has occurred so far.
After acquiring the group of adult Gilas, and having the two existing adult Gilas properly cooled to a chilly 53F in a modified wine cooler from Thanksgiving to March 1st, I was good to go. Unfortunately one of my females had some blood in her stool and was ultimately brought to a vet and has been receiving medicine (this experience will be another post soon), she is out of breeding for the year to ensure she is healthy. Always, the well-being of the animal must be first priority! I jumped the gun and started putting my Gila together about the middle of March (April 1st is the recommendation from M. Seward, or 4-6 weeks out of hibernation) to see who was who. I had a good guess on how the sexing game would play out as the head shape on the animals I have were apparent side by side. Two were questionable, but my guesses were accurate. I started by rotating the new Gilas with my 21-year-old, known sexed by ultrasound male and recording the interactions. I started with the Gila that was voted most likely to be a girl with my male. Then paired the most likely male to my male, again recording the interaction. One of those interactions was posted here, and I will put up a female to male video up soon.
Boys will be boys….
The interactions between the sexes is stark to say the least. Males, when faced with another male, reacted almost immediately and the ritualized male combat started. I can see where, when faced with no path of escape, the fighting can escalate to a vicious brawl and continue to the exclusion of breeding. It is intense! After safely removing the “losing” male, or the one that leaves the cage, the remaining male roams around huffing and puffing ensuring the competition has left. Interestingly, both males, the winner and the loser in their respective cages, start raising the tails and marking their territory with their cloaca. At one point, the winner had his hemipenis everted and he rubbed it about his cage. I then introduced a female into the cage. The interaction between males and females in my group could best be described as gentle, even romantic (in lizard terms) as both sexes start licking the air madly, picking up on the scent of the opposite sex. They then approached each other and continued tasting the air and each other with their tongues. It is a much slower pace than the instant male to male interaction, and eventually the male starts to chase the female around the cage in an attempt to copulate.
No Means No!
Even in the animal kingdom, no means no. In my case, the females that have been introduced into male cages have been, to my observations, not ready or unwilling to copulate. Did I introduce them to early? Have I somehow missed the short window that the female produces mature follicles? Time will tell at this point as I have not witnessed copulation in my group. The females, when, um, mounted by the males either run away and hiss or bite the male and then run away. But, after the initial night’s excitement the Gilas seem to pair up and are close to each other when resting or lounging around the terrarium. The Gilas are more active at night, and perhaps this is when copulation is taking place but as of right now I cannot know for sure. I did break out my old night vision monocular the other night to observe the pairs but saw more of the same; the females running from the males when approached. I kept the pairs together for a week and have rotated the females to different male’s cages in hopes there will be some compatibility between the pairs.
Q & A
So, I asked a few questions above that I will attempt to provide answers for based on my interpretation of what has happened with my Gilas. Please keep in mind that this is still new to me and I am answering on observations made in my group of Gilas. If different revelations or findings occur, these answers will be updated.
Q – Can you tell a male from female by head shape or appearance?
A – Yes and no. When I had only two Gilas and no idea of their sex there was no known commodity for each and no basis for comparison. If you buy or own a single Gila and do not have a friend with a colony or some known sexed animals I do not think an accurate determination could be made. When I bought the colony, it still wasn’t apparent who was who, but after a few days and taking measurements I made an uneducated guess based on this factor. By sheer luck I turned out to be right but still had to put them together to be 100% sure. Check the photo above and see if you can tell the difference. Not too easy, huh? I plan on doing other comparisons of the sexes on a future post.
Q – Why do you need a group or colony to breed?
A – While I cannot definitively answer this, it appears that the social structure of Gila monsters lends itself well to groups than single pairs. I am sure offspring can be had from just one pair, but I do not know how successful breeding would be overall. I do not think if I had just one pair at this point my chances would be that good. All successful Gila breeders I have spoken with recommend group breeding.
Q- What does male combat look like versus male to female interactions?
A – Male combat is a contest where the fighters engage each other head on, and aggressively. Male to female is overall a more gentle approach. Check out my YouTube channel to see the different interactions between my lizards.
Q – Is it better to keep them singly or in a group when attempting to breed?
A – From a maintenance standpoint, I believe keeping Gilas separately is the best way to go. If the one Gila that is sick was contagious, she may have spread it to the colony and my breeding hopes would have been dashed for the year and some of the Gilas may have died. Not to mention the vet bills increasing exponentially! Also, if a lizard has an issue or isn’t eating it is easier to tell when housed singly. For my breeding program I like to see how each Heloderma suspectum reacts to one another.
I will keep updating this blog as time goes, and feel free to email me with any questions or comments especially if you have successfully bred Gila monsters and can give some guidance.
Breeding season is upon me, and it couldn’t be more exciting! As this is my first time working with a group of Gila monsters, I was unsure of what male-to-male combat looked like versus male-to-female interactions. In books they look similar but from what I have seen so far it is a very different interaction. Now, I must say that my intention was not to stimulate breeding but to confirm the sexes of the lizards in my colony. I have read that male combat can be vicious in captivity as there is no escape for the subordinate male and can certainly see how it can escalate to this level after seeing my males briefly duke it out. I find it interesting that males do not waste time getting into combat when introduced to one another, while males and females take some time to find each other and the ensuing interaction is much more gentle (though, I have seen the females bite the males on several occasions so far). This is the first step in breeding, and has been very interesting to see these reptiles interact.
Below are a few videos shot on my Leica X Vario to help others see what male combat looks like in captivity. Please note that I was around the whole time during this interaction to ensure things did not get out of control. There was some biting in the beginning but it turned into a wresting match.