Successful Hatching of C. angulata - Sterantino / CAWG

Sterant

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5 Year Member
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Mar 6, 2016
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693
Location (City and/or State)
Albany, NY
It is with great pleasure and excitement that I can share with you that earlier today I successfully hatched my first Bowsprit tortoise. As many of you know this is a notoriously difficult species to reproduce in captivity outside of its natural range of South Africa.

A hand-full of US breeders have hatched a small number over the past 15 years, but the incubation methods are inconsistent. After starting the Chersina Angulata Working Group, and collecting data from a number of sources, I decided to use the following incubation strategy, and it worked - at least this one time. Though I am far from claiming we have figured it out, I do have some constants that seem to contribute to successful hatching.

Here is what I did:

The female nested in a mixture of soil and sand which is the substrate in the enclosure. Once she nested, I excavated the egg and re-buried it, using the same urine-soaked dirt she nested in, in a small rubbermaid container. I set the top on the container but did not snap it into place. Again, the egg was totally buried with about 1" of dirt on top. I did not put this container in an incubator, instead, I put it on a shelf in my heated tortoise room. The room is heated to 85F during the day (6:30am to 6:30pm) and slowly drops to 68F over night. Inside the container I placed a SensorPush sensor so I could measure temperature and humidity of the air above the dirt. Based on readings provided from natural nest data in South Africa, this 17f degree night drop was appropriate, as was incubating at or near 100% RH which I did the entire time. This high RH contradicts many opinions as to the proper RH for this species, but is in line with natural nest readings.

After 35 days, I brushed the dirt off the top of the egg so I could candle it and there were blood vessels beginning to form. I kept this process very short and only candled for a few seconds. From prior experience with developing embryos of this species, I have reason to believe that bright light negatively effects them, or at very least, really annoys them.

I would candle the egg using this process every few weeks and it continued to develop nicely. I would also lightly mist the dirt after every candling session to keep the RH up near 100%.

Unlike other species I work with, this egg never got opaque. I was able to see a good amount of space in various parts of the egg right up to the day before it hatched.

At 90 days of incubation, I only let my room drop to 75 at night rather than 68. I did this based on the natural nest data I received which showed an increase in both day-time and night-time temperatures as incubation progressed.

I was expecting the egg to hatch between 90 and 125 days as this was the range others had experienced, but they did not use a night drop. When it passed the 125 day mark without hatching, I convinced myself that the night drop I used (which the others did not) would logically add more time to the incubation. 9 stressful days later, at 134 days, it pipped. I peeled away a bit of the egg to be sure its head was not at risk of being stuck in any fluid, and it emerged from the egg a few hours later. There is a good amount of yolk sac that still needs to be absorbed, but it is very active and looks to be in good health.

I currently have 3 other eggs incubating and will report on them as they progress.

To date, the members of the CAWG have hatched 5 CB Angulates and we are well on our way to building the CB generation we set out to.

This was far from something I did on my own.

It was the prior experience and active help from a large group of people that I need to thank:

All the CAWG members - @HermanniChris , @kingsley , @Tom , Dwight Lawson, @zovick , @jonathan gray for their constant talks, meetings, advice and prior experience hatching this species, which @kingsley , Dwight and @HermanniChris have done. @jonathan gray even provided medical care to one tortoise while I was out of town.

@CarolM , @Markw84 and @Tom for providing the sensors, field labor and data collection/reporting for the wild nest data recorded in @CarolM 's back yard!

@Will, Jim Barzyk, David Mifsud and Brian Hennan for a number of good talks about their field time in South Africa observing Angulata and the person that runs the amazing startortoises.net website for a great resource and a number of valuable email exchanges, though I still don't know their name ;-)

Professor Retha Hofmeyer for her large number of amazing research papers on the species in the Wild.

Of course - many of these connections were the result of the Tortoise Forum - so many thanks here!

IMG_3468.JPG
 

Markw84

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Jan 17, 2012
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Sacramento, CA (Central Valley)
It is with great pleasure and excitement that I can share with you that earlier today I successfully hatched my first Bowsprit tortoise. As many of you know this is a notoriously difficult species to reproduce in captivity outside of its natural range of South Africa.

A hand-full of US breeders have hatched a small number over the past 15 years, but the incubation methods are inconsistent. After starting the Chersina Angulata Working Group, and collecting data from a number of sources, I decided to use the following incubation strategy, and it worked - at least this one time. Though I am far from claiming we have figured it out, I do have some constants that seem to contribute to successful hatching.

Here is what I did:

The female nested in a mixture of soil and sand which is the substrate in the enclosure. Once she nested, I excavated the egg and re-buried it, using the same urine-soaked dirt she nested in, in a small rubbermaid container. I set the top on the container but did not snap it into place. Again, the egg was totally buried with about 1" of dirt on top. I did not put this container in an incubator, instead, I put it on a shelf in my heated tortoise room. The room is heated to 85F during the day (6:30am to 6:30pm) and slowly drops to 68F over night. Inside the container I placed a SensorPush sensor so I could measure temperature and humidity of the air above the dirt. Based on readings provided from natural nest data in South Africa, this 17f degree night drop was appropriate, as was incubating at or near 100% RH which I did the entire time. This high RH contradicts many opinions as to the proper RH for this species, but is in line with natural nest readings.

After 35 days, I brushed the dirt off the top of the egg so I could candle it and there were blood vessels beginning to form. I kept this process very short and only candled for a few seconds. From prior experience with developing embryos of this species, I have reason to believe that bright light negatively effects them, or at very least, really annoys them.

I would candle the egg using this process every few weeks and it continued to develop nicely. I would also lightly mist the dirt after every candling session to keep the RH up near 100%.

Unlike other species I work with, this egg never got opaque. I was able to see a good amount of space in various parts of the egg right up to the day before it hatched.

At 90 days of incubation, I only let my room drop to 75 at night rather than 68. I did this based on the natural nest data I received which showed an increase in both day-time and night-time temperatures as incubation progressed.

I was expecting the egg to hatch between 90 and 125 days as this was the range others had experienced, but they did not use a night drop. When it passed the 125 day mark without hatching, I convinced myself that the night drop I used (which the others did not) would logically add more time to the incubation. 9 stressful days later, at 134 days, it pipped. I peeled away a bit of the egg to be sure its head was not at risk of being stuck in any fluid, and it emerged from the egg a few hours later. There is a good amount of yolk sac that still needs to be absorbed, but it is very active and looks to be in good health.

I currently have 3 other eggs incubating and will report on them as they progress.

To date, the members of the CAWG have hatched 5 CB Angulates and we are well on our way to building the CB generation we set out to.

This was far from something I did on my own.

It was the prior experience and active help from a large group of people that I need to thank:

All the CAWG members - @HermanniChris , @kingsley , @Tom , Dwight Lawson, @zovick , @jonathan gray for their constant talks, meetings, advice and prior experience hatching this species, which @kingsley , Dwight and @HermanniChris have done. @jonathan gray even provided medical care to one tortoise while I was out of town.

@CarolM , @Markw84 and @Tom for providing the sensors, field labor and data collection/reporting for the wild nest data recorded in @CarolM 's back yard!

@Will, Jim Barzyk, David Mifsud and Brian Hennan for a number of good talks about their field time in South Africa observing Angulata and the person that runs the amazing startortoises.net website for a great resource and a number of valuable email exchanges, though I still don't know their name ;-)

Professor Retha Hofmeyer for her large number of amazing research papers on the species in the Wild.

Of course - many of these connections were the result of the Tortoise Forum - so many thanks here!

View attachment 269019

Congratulations Dan! Great news.
 

CarolM

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Joined
Oct 30, 2017
Messages
19,492
Location (City and/or State)
South Africa - Cape Town
It is with great pleasure and excitement that I can share with you that earlier today I successfully hatched my first Bowsprit tortoise. As many of you know this is a notoriously difficult species to reproduce in captivity outside of its natural range of South Africa.

A hand-full of US breeders have hatched a small number over the past 15 years, but the incubation methods are inconsistent. After starting the Chersina Angulata Working Group, and collecting data from a number of sources, I decided to use the following incubation strategy, and it worked - at least this one time. Though I am far from claiming we have figured it out, I do have some constants that seem to contribute to successful hatching.

Here is what I did:

The female nested in a mixture of soil and sand which is the substrate in the enclosure. Once she nested, I excavated the egg and re-buried it, using the same urine-soaked dirt she nested in, in a small rubbermaid container. I set the top on the container but did not snap it into place. Again, the egg was totally buried with about 1" of dirt on top. I did not put this container in an incubator, instead, I put it on a shelf in my heated tortoise room. The room is heated to 85F during the day (6:30am to 6:30pm) and slowly drops to 68F over night. Inside the container I placed a SensorPush sensor so I could measure temperature and humidity of the air above the dirt. Based on readings provided from natural nest data in South Africa, this 17f degree night drop was appropriate, as was incubating at or near 100% RH which I did the entire time. This high RH contradicts many opinions as to the proper RH for this species, but is in line with natural nest readings.

After 35 days, I brushed the dirt off the top of the egg so I could candle it and there were blood vessels beginning to form. I kept this process very short and only candled for a few seconds. From prior experience with developing embryos of this species, I have reason to believe that bright light negatively effects them, or at very least, really annoys them.

I would candle the egg using this process every few weeks and it continued to develop nicely. I would also lightly mist the dirt after every candling session to keep the RH up near 100%.

Unlike other species I work with, this egg never got opaque. I was able to see a good amount of space in various parts of the egg right up to the day before it hatched.

At 90 days of incubation, I only let my room drop to 75 at night rather than 68. I did this based on the natural nest data I received which showed an increase in both day-time and night-time temperatures as incubation progressed.

I was expecting the egg to hatch between 90 and 125 days as this was the range others had experienced, but they did not use a night drop. When it passed the 125 day mark without hatching, I convinced myself that the night drop I used (which the others did not) would logically add more time to the incubation. 9 stressful days later, at 134 days, it pipped. I peeled away a bit of the egg to be sure its head was not at risk of being stuck in any fluid, and it emerged from the egg a few hours later. There is a good amount of yolk sac that still needs to be absorbed, but it is very active and looks to be in good health.

I currently have 3 other eggs incubating and will report on them as they progress.

To date, the members of the CAWG have hatched 5 CB Angulates and we are well on our way to building the CB generation we set out to.

This was far from something I did on my own.

It was the prior experience and active help from a large group of people that I need to thank:

All the CAWG members - @HermanniChris , @kingsley , @Tom , Dwight Lawson, @zovick , @jonathan gray for their constant talks, meetings, advice and prior experience hatching this species, which @kingsley , Dwight and @HermanniChris have done. @jonathan gray even provided medical care to one tortoise while I was out of town.

@CarolM , @Markw84 and @Tom for providing the sensors, field labor and data collection/reporting for the wild nest data recorded in @CarolM 's back yard!

@Will, Jim Barzyk, David Mifsud and Brian Hennan for a number of good talks about their field time in South Africa observing Angulata and the person that runs the amazing startortoises.net website for a great resource and a number of valuable email exchanges, though I still don't know their name ;-)

Professor Retha Hofmeyer for her large number of amazing research papers on the species in the Wild.

Of course - many of these connections were the result of the Tortoise Forum - so many thanks here!

View attachment 269019
Best news to wake up to. Very very happy for you Dan. Congratulations.
 

HermanniChris

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Sep 7, 2007
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Massive congratulations my friend. One more CB angulata on American soil. I’ve finally calmed down from your texts yesterday.
 

zovick

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Great work, Dan! I am sure this is just the first in your line of new offspring in the US.
 

jonathan gray

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Sep 9, 2014
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This is almost biblical in newsworthiness: I almost feel as if I've given birth myself! This is the result of an incredible amount of research, networking and 'turtle instinct' on Dan's part. I never had any doubt that it would happen...it was just a question of when. This baby is the first of many yet to come.
 

bouaboua

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Congrats! ! ! ! ! Hope to see more in the near future!
 

C. Nelson

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Joined
Nov 25, 2016
Messages
135
Location (City and/or State)
Grand Junction, CO
It is with great pleasure and excitement that I can share with you that earlier today I successfully hatched my first Bowsprit tortoise. As many of you know this is a notoriously difficult species to reproduce in captivity outside of its natural range of South Africa.

A hand-full of US breeders have hatched a small number over the past 15 years, but the incubation methods are inconsistent. After starting the Chersina Angulata Working Group, and collecting data from a number of sources, I decided to use the following incubation strategy, and it worked - at least this one time. Though I am far from claiming we have figured it out, I do have some constants that seem to contribute to successful hatching.

Here is what I did:

The female nested in a mixture of soil and sand which is the substrate in the enclosure. Once she nested, I excavated the egg and re-buried it, using the same urine-soaked dirt she nested in, in a small rubbermaid container. I set the top on the container but did not snap it into place. Again, the egg was totally buried with about 1" of dirt on top. I did not put this container in an incubator, instead, I put it on a shelf in my heated tortoise room. The room is heated to 85F during the day (6:30am to 6:30pm) and slowly drops to 68F over night. Inside the container I placed a SensorPush sensor so I could measure temperature and humidity of the air above the dirt. Based on readings provided from natural nest data in South Africa, this 17f degree night drop was appropriate, as was incubating at or near 100% RH which I did the entire time. This high RH contradicts many opinions as to the proper RH for this species, but is in line with natural nest readings.

After 35 days, I brushed the dirt off the top of the egg so I could candle it and there were blood vessels beginning to form. I kept this process very short and only candled for a few seconds. From prior experience with developing embryos of this species, I have reason to believe that bright light negatively effects them, or at very least, really annoys them.

I would candle the egg using this process every few weeks and it continued to develop nicely. I would also lightly mist the dirt after every candling session to keep the RH up near 100%.

Unlike other species I work with, this egg never got opaque. I was able to see a good amount of space in various parts of the egg right up to the day before it hatched.

At 90 days of incubation, I only let my room drop to 75 at night rather than 68. I did this based on the natural nest data I received which showed an increase in both day-time and night-time temperatures as incubation progressed.

I was expecting the egg to hatch between 90 and 125 days as this was the range others had experienced, but they did not use a night drop. When it passed the 125 day mark without hatching, I convinced myself that the night drop I used (which the others did not) would logically add more time to the incubation. 9 stressful days later, at 134 days, it pipped. I peeled away a bit of the egg to be sure its head was not at risk of being stuck in any fluid, and it emerged from the egg a few hours later. There is a good amount of yolk sac that still needs to be absorbed, but it is very active and looks to be in good health.

I currently have 3 other eggs incubating and will report on them as they progress.

To date, the members of the CAWG have hatched 5 CB Angulates and we are well on our way to building the CB generation we set out to.

This was far from something I did on my own.

It was the prior experience and active help from a large group of people that I need to thank:

All the CAWG members - @HermanniChris , @kingsley , @Tom , Dwight Lawson, @zovick , @jonathan gray for their constant talks, meetings, advice and prior experience hatching this species, which @kingsley , Dwight and @HermanniChris have done. @jonathan gray even provided medical care to one tortoise while I was out of town.

@CarolM , @Markw84 and @Tom for providing the sensors, field labor and data collection/reporting for the wild nest data recorded in @CarolM 's back yard!

@Will, Jim Barzyk, David Mifsud and Brian Hennan for a number of good talks about their field time in South Africa observing Angulata and the person that runs the amazing startortoises.net website for a great resource and a number of valuable email exchanges, though I still don't know their name ;-)

Professor Retha Hofmeyer for her large number of amazing research papers on the species in the Wild.

Of course - many of these connections were the result of the Tortoise Forum - so many thanks here!

View attachment 269019

What a wonderful contribution to science. Congrats!
 

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