Looking for information on a confiscation in the 1970s. I know the animals were sent off to an island off of Georgia, and were the source of many that ended up in zoos.
Just looking for the story
Just looking for the story
@zovick might have info on that.Looking for information on a confiscation in the 1970s. I know the animals were sent off to an island off of Georgia, and were the source of many that ended up in zoos.
Just looking for the story
Here you go, with the whole background story as well:Looking for information on a confiscation in the 1970s. I know the animals were sent off to an island off of Georgia, and were the source of many that ended up in zoos.
Just looking for the story
Thank you. What brought the interest was the dark coloration of specimens from that group vs many captive ones. I know part of that is likely related to some human selection, but there haven't been that many generations yet.That was St. Catherines Island and @zovick was very active with the Bronx Zoo (WCS) and St. Catherines back then. If anyone will have details it will be him!
Well, I have bred three generation of 100% CB Radiated Tortoises. That took about 40 years, and I was very careful to select my breeding animals for the coloration I desired.Thank you. What brought the interest was the dark coloration of specimens from that group vs many captive ones. I know part of that is likely related to some human selection, but there haven't been that many generations yet.
There's a motel in Kansas with carpeting down the hallway that immediately reminded me of radiated tortoises.Well, I have bred three generation of 100% CB Radiated Tortoises. That took about 40 years, and I was very careful to select my breeding animals for the coloration I desired.
I have also bred 3 generations of 100% CB Sri Lankan Stars which took about 20 years. It was easier to get the high yellow coloration in the Stars than in the Radiated Tortoises.
I have a theory that some of the difference in coloration between those early specimens (which were all WC animals) and the later CB animals may be due to the artificial incubation temperatures and a couple of other factors which are used for the eggs in captivity as compared to the actual nest temperatures in the wild.Thank you. What brought the interest was the dark coloration of specimens from that group vs many captive ones. I know part of that is likely related to some human selection, but there haven't been that many generations yet.
Are you aware of a sex ratio difference among captive hatchlings at those temperatures, and of wild ones?I have a theory that some of the difference in coloration between those early specimens (which were all WC animals) and the later CB animals may be due to the artificial incubation temperatures and a couple of other factors which are used for the eggs in captivity as compared to the actual nest temperatures in the wild.
Most people incubate Radiated Tortoise eggs at between 86F and 90F. A study of the actual temperatures within nests in the wild showed that the temperatures in the nests were pretty uniformly 73F for the entire incubation period and the in-situ eggs took much longer to hatch than the CB eggs. Wild nests took close to 9 months to hatch. Artificially incubated Radiated eggs take anywhere from about 90 to 110 days on the average.
This incubation temperature difference plus the selection of highly yellow captive specimens for breeding by humans are two differences that I can determine between the WC and CB animals. Humidity within the nests vs. humidity in artificial incubators is another possible factor in the color difference.
Additionally, it is doubtful from the study mentioned above that the wild eggs are ever subjected to temperatures as cool as those used by breeders prior to incubation of the eggs. I cooled many Radiated eggs at 54-64 degrees when I lived in CT. That may also be a factor in the difference in color.
I do know that way back in the 70's the eggs at St. Catherine's were incubated at 82, 84, and 86 degrees hoping for a good distribution of sexes in the young. All the babies turned out to be males, so the incubation temperatures were increased to 85, 87, and 89 which did produce both females and males. Remember that in order to tell the sexes of the offspring at that time, they had to be raised for about 8-10 years as there was no other way to sex them (other than euthanasia and dissection).Are you aware of a sex ratio difference among captive hatchlings at those temperatures, and of wild ones?
Has anyone ever incubated them at 73 in captivity? Is that an average nest temp for the 9 month duration of wild incubation, or is the actual temp inside the nest a constant 73 most of the time?I have a theory that some of the difference in coloration between those early specimens (which were all WC animals) and the later CB animals may be due to the artificial incubation temperatures and a couple of other factors which are used for the eggs in captivity as compared to the actual nest temperatures in the wild.
Most people incubate Radiated Tortoise eggs at between 86F and 90F. A study of the actual temperatures within nests in the wild showed that the temperatures in the nests were pretty uniformly 73F for the entire incubation period and the in-situ eggs took much longer to hatch than the CB eggs. Wild nests took close to 9 months to hatch. Artificially incubated Radiated eggs take anywhere from about 90 to 110 days on the average.
This incubation temperature difference plus the selection of highly yellow captive specimens for breeding by humans are two differences that I can determine between the WC and CB animals. Humidity within the nests vs. humidity in artificial incubators is another possible factor in the color difference.
Additionally, it is doubtful from the study mentioned above that the wild eggs are ever subjected to temperatures as cool as those used by breeders prior to incubation of the eggs. I cooled many Radiated eggs at 54-64 degrees when I lived in CT. That may also be a factor in the difference in color.
I wish I could go see the natural habitat (im not doing international travel at this time), or find some decent video/photography of it. I'd assume it was grassland like from the patterning of captive animals, but I'm not sure as dark individuals would be an easier spot in a grassland environment I would believe.Interesting to consider natural selection as well. Perhaps in the wild, super colorful babies are easier to spot and therefore are predated more than the less colorful babies - thereby leading to a less colorful community.
This thread turned out to be informative, would love to see more tid bits like this, perhaps in a centralized thread. Lot of history and information our community will loose over time.Has anyone ever incubated them at 73 in captivity? Is that an average nest temp for the 9 month duration of wild incubation, or is the actual temp inside the nest a constant 73 most of the time?
We are lucky to have you here Mr. Z. Thank you a million times over for sharing your knowledge and experience with us.
Not if members keep asking questions of our more experienced members. You obviously nailed your question. Thanks. That was interesting!!I wish I could go see the natural habitat (im not doing international travel at this time), or find some decent video/photography of it. I'd assume it was grassland like from the patterning of captive animals, but I'm not sure as dark individuals would be an easier spot in a grassland environment I would believe.
This thread turned out to be informative, would love to see more tid bits like this, perhaps in a centralized thread. Lot of history and information our community will loose over time.
I wish I could go see the natural habitat (im not doing international travel at this time), or find some decent video/photography of it. I'd assume it was grassland like from the patterning of captive animals, but I'm not sure as dark individuals would be an easier spot in a grassland environment I would believe.
This thread turned out to be informative, would love to see more tid bits like this, perhaps in a centralized thread. Lot of history and information our community will loose over time.
Perhaps I should of worded that better, but thank you for the link. The videos on the conservation don't tend to focus on the habitat itself, and are generally (like this one) less than high quality video.There are lots of videos on Youtube of people doing conservation in Madagascar. Here's one that shows biologists installing trackers on tortoises in the spiny forest ecoregion where the tortoises occur.
Congrats on the torts! Most people don't realize how lucky they are to have breeders in their state.
Hi Tom,Has anyone ever incubated them at 73 in captivity? Is that an average nest temp for the 9 month duration of wild incubation, or is the actual temp inside the nest a constant 73 most of the time?
We are lucky to have you here Mr. Z. Thank you a million times over for sharing your knowledge and experience with us.