It's why I trust the two I have from Chris will turn out as advertised.
Cool to see this. Is there a chance you recall where the study was available. I hate that question myself but then again I've got to ask. Hahahahaha.@Will The closest to a really good study I have seen on G platynota had the results of:
28.9°C produced 9 males and 1 female
30.0°C produced 14 males and 13 females
Young were endoscopically sexed to determine sex.
In the same incubators at the same time A radiata had results of
28.9°C produced 1:11.5 male/female ratio
30.0°C produced 100% female
This study suggests the pivot temperature and therefore the transitional range is lower than what I hear most people are using. Perhaps there is a high reversal in sex produced as in some chelonians where males are produced at the low range AND the high range???
Just wanted to jump in on this really quick to add some info to it.
The following pair were born here. Female on the left, male on the right. Female was incubated in an Avey Rept100 at 90.8F hatched at 89 days. Confirmed female. Male was incubated at 84.6F in a Little Giant Hovobator at 84.6F and hatched at 101 days. I have another 0.2 held back that turned out as such when incubated under the same conditions.
Cool to see this. Is there a chance you recall where the study was available. I hate that question myself but then again I've got to ask. Hahahahaha.
Here you go if it works to attach a PDF....
AND - Here's one for MEE but you probably have this one...
I know this sounds simplistic and still in the learning phase with regard to the Burm Star native environment, but when is the general time of the year females drop their clutches and what's the general temp at that time of the year?
Given the diapause need I assume it's when temps are 70-80 or so at tortoise level.
The environment of Redfoot's and Yellowfoot's doesn't typically go above 93-95 degrees if females drop during the hot part of the year, so sex determination would be/seems to be pretty consistent in my experience.
Same for Russian's in that "generally" eggs are laid and hatchlings appear just before before the onset of 95-105 daily temps hit them and they go into aestivation.
Yes, I remember those and they sure looked female then. Surprised one turned out male from the way they looked. But those are not one's Behler endoscoped to determine sex, so it's guess and pick. In 2008, they started incubating at 30° and had pretty much stayed in the 50/50 ratios. From my visits there, it seems they have transitioned up a bit more now to get more females.That's funny (The Behler Center PDF…) because they are one of the four sellers I spoke of. I bought 4 babies from them and we are currently at 1.1.2. The two little slow growers might turn out to be female, but one is a male for sure. Of course both little ones might turn out to be male too. My contact there is out of town in Africa right now, but he says to contact him next week when he returns for the details.
@Markw84 These are the little ones in the reptile room that you checked out.
Yes, I remember those and they sure looked female then. Surprised one turned out male from the way they looked. But those are not one's Behler endoscoped to determine sex, so it's guess and pick. In 2008, they started incubating at 30° and had pretty much stayed in the 50/50 ratios. From my visits there, it seems they have transitioned up a bit more now to get more females.
You don't remember pointing out that the second largest was clearly a male? I hadn't even looked for a long while. It was your visit and your observation that made me realize that that one was a male.
The 2 little ones continue to grow very slowly. They are in the neighborhood of 200 grams each. Biggest one is probably around 1000 now. No indication one way or the other yet on the two small ones.Yes but I remember the other 3 looked very female. Surprised they are not obvious yet. Gotta be close to 1000 g now?
Ernie:
Burmese stars normally lay in the winter. So right now is pretty much the start of egg laying time in their native range. They seem to follow the same schedule in captivity.
The heart of their prime range in Dec & Jan has an average high of 81° and average low of 64°. That is also their "dry" season with little rain (avg precipitation for Dec - Feb totals 0.18") and humidity running from 50% - 70%. By April, when the eggs should be incubating and developing "mid term" the average high is 95° with an average low of 82°. By May and June, the average high is up to 96° and 91° with lows of 85° and 83°. That is beginning of monsoon season and rain averages 5-6" those months.
So with my tests on nest temps when I get similar temperatures as their winter, the nests and ground temps are probably around 70°. I don't know what April and incubating temps would then be as I have never been able to test where overnight lows are 82°!!
I do agree that they can indeed be the "poster tortoise" for captive propogation. Keeping in mind this paper was written in 2011 and just a year or so before one of the research teams sent to find wild G platynota failed to find a single one, the outlook for the tortoise was indeed bleak and most agreed there was not enough population density to support sustainabiliby - guessing that they still must be out there somewhere!Thanks much @Markw84 I have recently re-read the Emer paper. So many folks were seeking to have a good guess on the sex outcome of some M.e.p. It seems like the Behler Center paper is in my memory, but who knows, I read it or reread it just now with a different critical eye. I don't recall ever reading anything with Kuckling being involved without some dramatic statement that they are 'all gone from the wild.' Don't get me wrong, he is one of the most skilled writers in the world of chelonian literature, he sets the bar from my perspective and is always reachable in person for a good conversation no matter the experience/knowledge of who he is talking with. But that phrase "functionally extinct in the wild" has no traction for me anymore.
It would seem that if that is true, they had been 'functionally extinct in the wild' then captive propagation has turned them so far around we might be seeing them in rescue shelters some time in the future. They have to be the poster tortoise for "hobby breeders". Good thing they did not get put on the ESA list.
ErnieDo any of you have F2's breeding right now and if so are they also holding to the same egg laying timing as wild caught?
Do any of you have F2's breeding right now and if so are they also holding to the same egg laying timing as wild caught?
I do agree that they can indeed be the "poster tortoise" for captive propogation. Keeping in mind this paper was written in 2011 and just a year or so before one of the research teams sent to find wild G platynota failed to find a single one, the outlook for the tortoise was indeed bleak and most agreed there was not enough population density to support sustainabiliby - guessing that they still must be out there somewhere!
Since then the wildlife preserve at Minzontaung has produced some amazing numbers with an estimated 4000 hatchlings expected just this year and a few hundred already released into "protected" areas. But it is the captive breeders that I believe has had the biggest impact. They are now possible to obtain and viable captive colonies are instead creating a CB supply.
ABSOLUTEY - A great thing they were not on the ESA list or this probably would not have happened.