New Baby Rads

BlakeATX

Well-Known Member
5 Year Member
Joined
Oct 11, 2013
Messages
113
Location (City and/or State)
Austin Texas
Number 7 hatched with a very large veiny egg sack attached. I’m very concerned about it but I read through the past posts on what to do. I have it on moist paper towels in the incubator. It’s pretty lethargic but I hope the little absorbes it in the coming days and makes it :-(
Number 7 continues to improve. Really scared me for a bit with how much wasn’t absorbed. It really looked like it’s insides were hanging out, but thanks to past posts on this topic, I was able to figure out what to do. Just a little bit of yolk remaining. It ate this morning for the first time and is becoming more active. Hopefully it will be fully healed in the next 2 days and can join it’s siblings!
 

Sterant

Well-Known Member
5 Year Member
Joined
Mar 6, 2016
Messages
693
Location (City and/or State)
Albany, NY
Thanks for the reply. Most every account I see uses that or very similar temps to break diapause. I really intrigues me that what works so well in artificial incubation is so unlike what a wild nest would ever experience! A wild nest would never see temps dip even below the mid 70°s!! - IN the "coldest" part of winter.
@Markw84 - I am trying to track down the researcher so that I can provide the paper I am referring to, but Bill Z told me about it a couple years ago. This research involved monitoring wild radiata nests in Madagascar tracking temperature and other data points. A couple things to note - First, the average nest temperature was only 73f or so. Also, the 6 month batteries in the sensors did not last long enough for the eggs to hatch - he needed to switch to 12 month batteries. These long incubation periods would indicate low incubation temperatures. In captivity, radiata eggs incubated at 87f hatch in around 90 days.

So this is a long way of saying that it is possible wild nests could get down into the diapause temperatures we use in captivity of 65f for extended periods.

I will provide the research paper if I can track him down.

This is also interesting as we get more data from Carol in South Africa from the temperature sensors she placed for us. I am learning a lot from that.

Dan
 

Markw84

Well-Known Member
10 Year Member!
Platinum Tortoise Club
Joined
Jan 17, 2012
Messages
5,041
Location (City and/or State)
Sacramento, CA (Central Valley)
@Markw84 - I am trying to track down the researcher so that I can provide the paper I am referring to, but Bill Z told me about it a couple years ago. This research involved monitoring wild radiata nests in Madagascar tracking temperature and other data points. A couple things to note - First, the average nest temperature was only 73f or so. Also, the 6 month batteries in the sensors did not last long enough for the eggs to hatch - he needed to switch to 12 month batteries. These long incubation periods would indicate low incubation temperatures. In captivity, radiata eggs incubated at 87f hatch in around 90 days.

So this is a long way of saying that it is possible wild nests could get down into the diapause temperatures we use in captivity of 65f for extended periods.

I will provide the research paper if I can track him down.

This is also interesting as we get more data from Carol in South Africa from the temperature sensors she placed for us. I am learning a lot from that.

Dan

Perhaps @Yvonne G would like to move your comment and my reply here and start a new thread? Don't want to hijack Blake here!


Dan

I find this all extremely interesting as I am finding a lot of what really seems to be going on in nests is quite different than what we all have been using to incubate eggs!

I would love to see that study as it is contrary to any data I have seen on weather in SW Madagascar. Unless all the weather data I have is inaccurate, I see no way a nest could get that cold. The air temp never gets that cold and nests 6" deep stay much warmer than the overnight low.

I have a lot of data, graphs, formulas, etc that I have been using to calculate the way nests act in the wild to really do justice to an answer to your question.

Let me see if I can do it more briefly.

I have been studying weather data for the best range locations I can find for sulcatas, platynota, angulata, radiata, and pardalis pardalis and I have a full years worth now. I needed to look at temps over that day, not just high and low, as well as rain events and cloud cover.

I correlated with studies on ground temps at various depths from a lot of passive heating data. I then also have a test study where I have a probe at 13" (sulcata depth) and 6" (platynota) as well as we are getting Carol's info at 2-3" depth.

From all that I can see how daily temps affect temps at the various depths. I can show results and graphs in another thread if needed and not destroy Blake's thread here.

Bottom line, with all the data from the center of prime radiata range (I used Marolinta, Madagascar) the two week average temperature never dropped below 75°. A 6" deep nest stays very close to the average temperature of the past two weeks. The temps in SW Madagascar are quite stable. Due in part to the warm ocean currents that surround the island and keep water temps in the low 80°s. Daily high/low swings only average between 10°f - 15°f unlike out temps we experience. If sun exposed, a 6 " nest does vary up to 6° with the low temp pretty close to the two week average and the high going up from there (in winter with deeper ground temps warmer).

According to all the data I see from other nests, I can see no way a nest in Madagascar will ever get below 73° on the coldest morning. Here is a graph showing Weather over last winter May - mid July for Marolinta. This is just a portion of the whole year to get the graph to show on one page. So the legend on left does not show. I did make the red bar highlight 80°- 85° for easy reference. Green is 70° - 75° and Blue is 60° - 65°. Bold red graph is the daily temp every 3 hours. Yellow is humidity. grey is % cloud cover. Dark blue is rain events. The red line over temps is the running 2 week average. The dark grey line is a 2 day running average. Between those two is where a nest temp will normally stay.

Marolinta winter.jpg
 

Sterant

Well-Known Member
5 Year Member
Joined
Mar 6, 2016
Messages
693
Location (City and/or State)
Albany, NY
Mark,
Thanks for the detailed response. It is certainly interesting stuff and has already impacted the way I incubate. I will do my best to track down the research I mentioned. The data you presented here is certainly convincing. My account of the research is all through conversations so perhaps something in the report will either contradict what I heard or provide an explanation. I will get back to this as soon as I can.

Dan
 

BlakeATX

Well-Known Member
5 Year Member
Joined
Oct 11, 2013
Messages
113
Location (City and/or State)
Austin Texas
Perhaps @Yvonne G would like to move your comment and my reply here and start a new thread? Don't want to hijack Blake here!


Dan

I find this all extremely interesting as I am finding a lot of what really seems to be going on in nests is quite different than what we all have been using to incubate eggs!

I would love to see that study as it is contrary to any data I have seen on weather in SW Madagascar. Unless all the weather data I have is inaccurate, I see no way a nest could get that cold. The air temp never gets that cold and nests 6" deep stay much warmer than the overnight low.

I have a lot of data, graphs, formulas, etc that I have been using to calculate the way nests act in the wild to really do justice to an answer to your question.

Let me see if I can do it more briefly.

I have been studying weather data for the best range locations I can find for sulcatas, platynota, angulata, radiata, and pardalis pardalis and I have a full years worth now. I needed to look at temps over that day, not just high and low, as well as rain events and cloud cover.

I correlated with studies on ground temps at various depths from a lot of passive heating data. I then also have a test study where I have a probe at 13" (sulcata depth) and 6" (platynota) as well as we are getting Carol's info at 2-3" depth.

From all that I can see how daily temps affect temps at the various depths. I can show results and graphs in another thread if needed and not destroy Blake's thread here.

Bottom line, with all the data from the center of prime radiata range (I used Marolinta, Madagascar) the two week average temperature never dropped below 75°. A 6" deep nest stays very close to the average temperature of the past two weeks. The temps in SW Madagascar are quite stable. Due in part to the warm ocean currents that surround the island and keep water temps in the low 80°s. Daily high/low swings only average between 10°f - 15°f unlike out temps we experience. If sun exposed, a 6 " nest does vary up to 6° with the low temp pretty close to the two week average and the high going up from there (in winter with deeper ground temps warmer).

According to all the data I see from other nests, I can see no way a nest in Madagascar will ever get below 73° on the coldest morning. Here is a graph showing Weather over last winter May - mid July for Marolinta. This is just a portion of the whole year to get the graph to show on one page. So the legend on left does not show. I did make the red bar highlight 80°- 85° for easy reference. Green is 70° - 75° and Blue is 60° - 65°. Bold red graph is the daily temp every 3 hours. Yellow is humidity. grey is % cloud cover. Dark blue is rain events. The red line over temps is the running 2 week average. The dark grey line is a 2 day running average. Between those two is where a nest temp will normally stay.

View attachment 265503
All good! This thread isn’t about me :) It’s about rad babies, eggs, nesting. I find it all very interesting as well!
 

Sterant

Well-Known Member
5 Year Member
Joined
Mar 6, 2016
Messages
693
Location (City and/or State)
Albany, NY
Perhaps @Yvonne G would like to move your comment and my reply here and start a new thread? Don't want to hijack Blake here!


Dan

I find this all extremely interesting as I am finding a lot of what really seems to be going on in nests is quite different than what we all have been using to incubate eggs!

I would love to see that study as it is contrary to any data I have seen on weather in SW Madagascar. Unless all the weather data I have is inaccurate, I see no way a nest could get that cold. The air temp never gets that cold and nests 6" deep stay much warmer than the overnight low.

I have a lot of data, graphs, formulas, etc that I have been using to calculate the way nests act in the wild to really do justice to an answer to your question.

Let me see if I can do it more briefly.

I have been studying weather data for the best range locations I can find for sulcatas, platynota, angulata, radiata, and pardalis pardalis and I have a full years worth now. I needed to look at temps over that day, not just high and low, as well as rain events and cloud cover.

I correlated with studies on ground temps at various depths from a lot of passive heating data. I then also have a test study where I have a probe at 13" (sulcata depth) and 6" (platynota) as well as we are getting Carol's info at 2-3" depth.

From all that I can see how daily temps affect temps at the various depths. I can show results and graphs in another thread if needed and not destroy Blake's thread here.

Bottom line, with all the data from the center of prime radiata range (I used Marolinta, Madagascar) the two week average temperature never dropped below 75°. A 6" deep nest stays very close to the average temperature of the past two weeks. The temps in SW Madagascar are quite stable. Due in part to the warm ocean currents that surround the island and keep water temps in the low 80°s. Daily high/low swings only average between 10°f - 15°f unlike out temps we experience. If sun exposed, a 6 " nest does vary up to 6° with the low temp pretty close to the two week average and the high going up from there (in winter with deeper ground temps warmer).

According to all the data I see from other nests, I can see no way a nest in Madagascar will ever get below 73° on the coldest morning. Here is a graph showing Weather over last winter May - mid July for Marolinta. This is just a portion of the whole year to get the graph to show on one page. So the legend on left does not show. I did make the red bar highlight 80°- 85° for easy reference. Green is 70° - 75° and Blue is 60° - 65°. Bold red graph is the daily temp every 3 hours. Yellow is humidity. grey is % cloud cover. Dark blue is rain events. The red line over temps is the running 2 week average. The dark grey line is a 2 day running average. Between those two is where a nest temp will normally stay.

View attachment 265503
@Markw84 et al. Here is the chart that outlines Thomas E.J. Leuteritz's findings as it relates to the various temperatures of 6 wild A. radiata nests in Cap Sainte Marie, Madagascar. Interestingly, we see a low nest temp of 14.6C which is 58.28F. We see Mean nests temperatures around 24C / 75F and high temps of 42.9C / 109.2F.

Also note incubation periods around 300 days with nests depths around 12 cm.

So, assuming these temperatures are correct, or even close to correct, these wild nests did experience temperatures in the range (and below) of what we use for captive diapause, namely 65F. And the incubation periods are long enough that they could be at those low temperatures for extended periods of time.

I am trying to have a talk with Mr. Leuteritz, but haven't connected yet.

Dan

Screen Shot 2019-02-27 at 5.03.17 PM.png
 

Markw84

Well-Known Member
10 Year Member!
Platinum Tortoise Club
Joined
Jan 17, 2012
Messages
5,041
Location (City and/or State)
Sacramento, CA (Central Valley)
Thank you so much for finding this. But a few things just don't make sense at all to me...

Why are they using data from nests that are in a completely different part of Madagascar - far away from the range of radiata? Perhaps this is just a protected reserve where they have moved confiscated tortoises for an assurance colony?

If i look at the weather data I can get for Toamasina (where Cap Sainte Marie is located) I get the following results for the past 3 years there:

Toamasina Madagascar weather.jpg

As you can see, according to this history, the average overnight low mid winter is right around 67°. From every nest and test nest I have tracked results for, the low nest temperature NEVER dips below the monthly AVERAGE temperature in winter when the lower ground temp is warmer than the surface. Even in peak summer, the overnight nest low rarely dips a few degrees below the monthly average when lower ground temps are cooler than surface temps. This is considering a 4" nest which is close to what we are getting with Carol's data.

Here is the actual data we are getting from Carol to show you what I mean. Gray is air temp. Red is Nest temp.dark brown is monthly average low air temp. Green is monthly average air temp. ( I didn't change the legend as I track weekly and 2 week averages and just changed the formulas to produce this chart.) You can see the nest temp never dips even close to the average overnight low. In fact, it rarely dips below the monthly aveage air temp (as this is the summer and hottest time of year there so lower ground is cooler than surface).

I have no idea how they could ever get the nest temperatures they are showing in the above chart you posted. It is physically impossible unless when they did the study, it was an extraordinarily cold year.

Chersina nest data vs monthly low and avg.jpg
 

Sterant

Well-Known Member
5 Year Member
Joined
Mar 6, 2016
Messages
693
Location (City and/or State)
Albany, NY
Thank you so much for finding this. But a few things just don't make sense at all to me...

Why are they using data from nests that are in a completely different part of Madagascar - far away from the range of radiata? Perhaps this is just a protected reserve where they have moved confiscated tortoises for an assurance colony?

If i look at the weather data I can get for Toamasina (where Cap Sainte Marie is located) I get the following results for the past 3 years there:

View attachment 266078


View attachment 266080
Those are all good observations and questions. I have been trying to speak with Mr. Leuteritz, but have been unsuccessful. Why they tested nests in that particular area (the reserve idea sounds likely) and what his thoughts are on the temperatures he gathered would be of primary interest.

I don't have any answers for you but hope to speak with him soon and learn more.
 

Markw84

Well-Known Member
10 Year Member!
Platinum Tortoise Club
Joined
Jan 17, 2012
Messages
5,041
Location (City and/or State)
Sacramento, CA (Central Valley)
Those are all good observations and questions. I have been trying to speak with Mr. Leuteritz, but have been unsuccessful. Why they tested nests in that particular area (the reserve idea sounds likely) and what his thoughts are on the temperatures he gathered would be of primary interest.

I don't have any answers for you but hope to speak with him soon and learn more.
I started thinking the source for weather data I used could be off. So I looked for an official weather station and there is one in Toamasina. Here is the summary from that official world weather network station:

SO they show an extended winter of average lows right around 63°. June through Sept. The average temp during that period right about 71°. This is about 5° lower than the report I referenced above, but still cannot produce a 58° nest temp. With the lower temp spread daily high to low in Madagascar, there would still have to be at least a consecutive week to 10 days with a low of 50° and high of 65° to get a nest to 58°.

I am perplexed!

Toamasina official station.jpg
 

Markw84

Well-Known Member
10 Year Member!
Platinum Tortoise Club
Joined
Jan 17, 2012
Messages
5,041
Location (City and/or State)
Sacramento, CA (Central Valley)
@Sterant

Dan, I just went through my documents and Have a complete radiata study by Leuteritz. One question solved - There is another Cap Sainte Marie at the very southern tip of Madagascar in prime radiata range. So that is the Cap Sainte Marie he is referencing. This study did not have any of the nesting data you reference above, though.

I found the weather station for Faux Cap which is nearby and here are those averages. Much closer to what would produce the possible temps referenced above! July has an average min of about 55°. A cold spell could just produce a one time low of 58°!

I wish he had more data of the timeline data from the logger. Not just a one time minimum.

Faux Cap.jpg
 
Last edited:

Sterant

Well-Known Member
5 Year Member
Joined
Mar 6, 2016
Messages
693
Location (City and/or State)
Albany, NY
@Sterant

Dan, I just went through my documents and Have a complete radiata study by Leuteritz. One question solved - There is another Cap Sainte Marie at the very southern tip of Madagascar in prime radiata range. So that is the Cap Sainte Marie he is referencing. This study did not have any of the nesting data you reference above, though.

I found the weather station for Faux Cap which is nearby and here are those averages. Much closer to what would produce the possible temps referenced above! July has an average min of about 55°. A cold spell could just produce a one time low of 58°!

I wish he had more data of the timeline data from the logger. Not just a one time minimum.

View attachment 266083
Right - these lows could have been for 5 minutes on 1 particular day. When I get a chance to talk to him, I will see if I can get the full data set.

As always - the weather station data could have been sampled on a roof top and not down at ground level.
 
Last edited:

zovick

Well-Known Member
10 Year Member!
Joined
Nov 17, 2013
Messages
3,388
@Sterant

Dan, I just went through my documents and Have a complete radiata study by Leuteritz. One question solved - There is another Cap Sainte Marie at the very southern tip of Madagascar in prime radiata range. So that is the Cap Sainte Marie he is referencing. This study did not have any of the nesting data you reference above, though.

I found the weather station for Faux Cap which is nearby and here are those averages. Much closer to what would produce the possible temps referenced above! July has an average min of about 55°. A cold spell could just produce a one time low of 58°!

I wish he had more data of the timeline data from the logger. Not just a one time minimum.

View attachment 266083

You have to consider the fact that Tom Leuteritz published his PhD thesis from which this chart was taken in 2002; hence he probably did this study sometime in the late 90's to 2001, so the technology may not have been able to capture the details which can be had with today's instruments. I know he told me that the eggs were taking much longer to hatch than he had anticipated, and he had to replace the 6 month batteries with 1 year ones to continue getting his data.
 
Top