Reptile & Amphibian Forums

I've had really good luck with my male Giant Day, I've called him Dingo mainly as a joke. Anyway I've had him for a year now and I'm 100% sure his a male and full grown. He has the best markings I've seen. I'm just worried if i get him mate would he hurt him or vise versa. The tank is a 20 gallon high and there are lots of hiding places. Is getting him a mate to risky or not?

I always recommend not to keep this species in tanks smaller than 65 g. 20 g makes them pretty immobile and often obese and almost always agressive. To me thisis not the right way to keep them.
In the tank he inhabits noe, he very likely will rape and then kill any female you introduce.
Provide a bigger tank and put the two gex into it simultaneously. He may still first rape her, but chances then will be good they get along well.
Please believe me, I have 19 years of experience with this species. That so many people keep these hardy critters in tiny tanks does not mean that its OK.

Ci@o

Ingo

It doesn't mean that it is not OK either. We have been keeping and breeding Phelsuma for years as well. Just because a person says they have the experience doesn't make them the final expert.A 65 gallon tank doesn't mean that they will not fight. We have grandis that always tiff in small and larger enclosures. It is just the particular nature of the individual. If you plan on breeding plan on having some scarring. It may never happen to you but it does happen. This is a reality you must be willing to deal with beforehand. It is up to you if you want to take that chance and breed a truly remarkable animal. They are alot of fun as you have already found out and breeding and rearing the young is just as rewarding. When making decisions like this don't just take one persons word for it. Ask around check out websites, go to shows and talk to breeders. Get all of the information that you can before you decide. I only say this because I have seen and heard people say well so and so said that we should do it this way. Find out for yourself. What works for me may not work for you.

This is not meant to offend anyone here we would just like to see all experiences show not just one side. We are all here to help each other out and to share our failures and success stories with those who would ask for our opinions. Right?
The Rep Room

Yes, thats definitely true. Some grandis individuals will fight in any enclosure. But in a larger enclosure, the chances are higher that two randomly selected individuals will get along well.
And still I do not think that a 20 g tank can give a 10" arboreal lizard enough room to run, jump, climb, find cooler and warmer, brighter and shadier places. So I stick to my recommendation of 65g and more.
With resopect to intraspecific agression, it helps if you raise the babies in groups. They tend to less agressive than animal raised as singles.
Also I am doing selective breeding since approx 15 years with the aim to yield low agressivity grandis.
Of course this includes inbreeding, but to my experience, this is not detrimetal for grandis. I still have 100% hatching rate and no animals die as babies.
At the moment I am able to keep 1,3 of my grandis together (200g tank) without any problems with agressivity or dminance.
All females produce fertile eggs and even though they already live together for several years you won´t find mating scars on the females.
I keep contact to many people who aquired grandis from my bloodline and so I can say that their experience with respect to agressivity is similar to mine. But still about 5-10% of the babies turn out to be of higher agressivity.

Thats just my experience

Ci@o

Ingo

Interesting with the group raising. We prefer to keep our bloodlines seperate do that we can provide unrelated offspring but the idea is still interesting. We always have housed them seperately so that growth rate, feeding etc could be monitored for each individual. I definitely agree if you plan on breeding in a group situation that a larger tank is preferred. Have you had any luck. I would have to disagree with the inbreeding though. We feel that any animals no matter reptile, mammal do not benefit from inbreeding. Just our opinion but we would prefer to expand the gene pool. You may not notice any problems even after 15 years but an extensive study of longevity, production, size etc would have to be done before you could rule out any detriment to the bloodlines. Again just our opinion. I know that you said that you are raising the grandis to be less agressive, have you tried working on the standings as well? I would like to hear your thoughts on group breeding of them as well. Either way it goes to show that two people can be breeding the same species and have totally different experiences to share. Thanks for your input and I hope the individual who started this message got the information that they wanted.

Kurt

Hi Kurt,

no, I have not yet worked with standingis.
But with respect to inbreeding. Sometimes it helps to have a PhD in Biology and so I have done quite some homeworking on this subject.
Its a fact that inbreeding lowers allelic variety. Thats undisputable, OK. But sometiems this ends up in finding a balance between wanted and unwanted effects of this outcome.
Inbreeding can be very detrimental to one species and comnpeltely harmless for another. That very likely depends on the temporal distance to the last population bottleneck of the respective species.
If that is long ago, a high degree of heterozygosity has accumulated in the populations of question. If not, the degree of heterozygotism can bemuch lower and the frequency of potentially detrimetal allelic variants can be very low.
There are many examples out there: Look at all these millions of goldhamstzers, which originate from the litter of a singel female importes approx 50 yeas ago. Look at all the budgies and beardies-all result of excessive inbreeding.
All these are species which obviously are highly resistant against inbreeding depressions.
On the other hand, many aquarium populations of Cichlid and Characid fish vanished after a few generations of unavoidable inbreeding and from expereince with chameleons I may conclude that many Chamaeleo species are quite sensitive gainst inbreeding.
But with careful selection of breeder animals, chosing only strong and apparently healthy individuals, serious breeders in many cases can overcome the negative aspects of inbreeding-just look at the veiled chameleons: So many people do report inbreeding problems-but with carefully selected breeder specimens you easily produce strong and healthy offspring.
And longevity? Of course, its almost impossible to select for that-animals do breed before they die.
But if you have a close eye on health of the animals you choose for breeding, you in most cases end up with long living specimens.
And with respect to grandis: At least for my strain, I do not see any detrimental inbreeding effects. Neither do I observe reduced hatch rates nor do strange colour variants pop up and egg production doe snot go down, but increases.
Having had males which make females look poor and ugly and full of mating scars after only a few years of breeding, I felt the need to select for less harsh mating behaviour.
In the wild grandis may live some 4-6 years. In captivity they can accumulate mating scars over decades. So it makes sense to reduce the frequency of injuries during mating. That was my original aim. On the way I found out that females coming out of this project turned out to be less agressive at well and I then had a close eye on them. With interesting specimens I mostly do back-crosses with one parent and also mate them to siblings originating fromn the other parent and a less related animal. I have best experiences with this procedure.
And to my opinion group raising is important as well. Animals get used to the presence of their own kind and even though most of theirt behaviour is inborn, they have the opportunity to practice intraspecific communication.
Its a highly unnatural situation that a lizard grows up without ever meeting others of its kind.
Of course, you need to have a closer eye on these groupos than on the single animal. Extraordinaryliy agressive specimens have to be sorted out quickly-but the result is worth the effort.

Just my 2 cts

Ci@o

Ingo

Not just two cents...I am completely fascinated with this concept. It is quite interesting to me. I hate to keep dragging this on. Would you happen to have this information published anywhere? It would make for an interesting read and I would like to try and incorporate some of these concepts into my own program. We are selectively breeding for increased red coloration and along the way found someinteresting anomalies(spelling?) but to be able to breed for temperment is just unique. You should come to the National Reptile Breeders Expo in Dayonta and give a talk on the subject. I think the people there would be very interested in hearing your experiences. Thanks for the insight and for your time in detailing some of you work. I really appreciate you taking the time to do that. I hope that others on the forum benefit from it as well.

Kurt

Sorry, I am german and I live in gGermany. So I am in the US mainly for business trips and my schedule normally does not allow me to give talks on herpetocultural subjects.
In fact I have given several talks on grandis in Germany, I have published a few articles on them and at the moment I am busy with a small booklet on captive care of P. mad. grandis.
Sadly thats all in German.
But anyhow, for this book I would love to have Pics of deviantly coloured grandis speciemns.
So I would greatly appreciuate if you could send me such Pics. Of course , you will be acknowledeged for in the book and I guess it would be worth a free copy-sadly again in german.

best regards

Ingo

Sure no problem. We will get some pics together and e-mail them to you to see if you could use them for your book. Most of all of the good information out there is in German anyway. My wife is trying to get me to take on learning German so that I can read some of the books we already own.We will e-mail you soon mail them soon. It was good to make your acquantince

Kurt

Hi Kurt,

thanks a lot in advance. My email is ingo.kober@phenex-pharma.com
My editor somewhat dislikes digital fotso and I can only satisfy him, if I provide at least 2.1 Mio Pixel in Tiff format.
Is that possible for you?

Best regards

Ingo

My wife is the expet there but it should not be a problem. Give us some time to get some good shots and we will e-mail them off to you.

Kurt

I am looking forward to that.
Thank you in advance!

Ingo