120 replies to this topic

[Foogoo]

 and low humidity to incubate their eggs and for pupal development and simultaneous lower temps and higher humidity for larval growth. This is just not possible in a small environment. 

 

Is this documented anywhere? Not that I don't believe you, I'm just curious since I haven't been able to find much documentation on humidity levels for specific genus/species.

[Retroman]

Here is one such reference on the humidity requirement for different stages of brood: 

 

https://books.google...omyrmex&f=false

 

I have been keeping Pogonomyrmex species for many years and have seen this phenomenon consistently. Can some larvae survive at low humidity levels? Yes, but my personal observation is they have a greater chance for survival through to adult when raised in higher humidity areas

[Retroman]

After I saw your inquiry today, I started looking around for research papers that examined the importance of a humidity gradient in larval development.

 

This one is directly on-point: https://journals.lib...ile/27968/26431

 

Most of the paper is focused on the importance of temperature gradients, but this section sums up the moisture factor: 

 

Activity patterns in harvester ants are strongly affected by moisture, and many species of Pogonomyrmex will forage at odd times if the soil is wet (Whitford and Ettershank 1975, Gordon 1991). Brood individuals have a thin cuticle and are more sensitive than adults to conditions of low moisture. Moisture patterns in the nest soils provide an important humidity gradient that harvester ants can exploit to protect their brood from desiccation (MacKay 1981). The effect of humidity on larval development was dramatic in the fire ant Solenopsis invicta. Larvae in chambers with less than 100% humidity were not fed by workers, died of starvation, and were eventually cannibalized (Cassill and Tschinkel 2000). In the lab portion of the present study, nurse workers continually moved brood from dry to moist soil within the chambers, suggesting that brood relocation behavior in P. salinus is influenced directly by humidity. In conclusion, P. salinus nurse workers are not strictly tied to an endogenous rhythm, but instead exhibit a high degree of behavioral flexibility in moving brood to temperatures and possibly humidity levels that facilitate brood development. 

Edited by Retroman, September 12 2016 - 7:34 PM.

[dspdrew]

Update 9-13-2016

 

I just noticed one of the queens has a little pile of eggs, so that's a good start. I'm still working on getting something larger ready for them.

[dspdrew]

Update 10-22-2016
 
The desert finally saw some rain September 20th 2016. This was the first rain of the entire summer in most of the Mojave desert. There wasn't really any heavy rain, but it rained long enough to drop about .3 inches. Since it rained lightly for a long period of time, the rain was able to soak into the ground a bit deeper, triggering some mating flights.
 
I went to Palm Desert to hopefully catch a nuptial flight. It continued raining into the morning of the next day there, and was cloudy for most of that day, so I headed out there the day after that in hopes that the sun would be shining in the morning. They fly pretty late in the year, so I was pretty sure that was going to be the day.
 
Sure enough, just as the sun was coming up, the alates started coming out. By around 10:00 AM they were taking off.
 

 

 

 

 

 

 

 

 

 



I never actually saw any of them mating, but a little further to the east of that location, I found tons of dealates running around later in the afternoon.

I saw a few of them digging founding chambers.


 
 
I brought some alates home with me to try breeding them the way Retroman does.
 
I got them to start mating, but I'm not sure if any were successful.
 

 
 
So far only one of the alates has eggs, and I can't tell if any of them are turning to larvae.
 
One of the captive-bred queens Retroman gave me has one nanitic now. The other had some brood, but it seems to be gone now.
 
Most of the queens I caught during that nuptial flight now have brood.

[CallMeCraven]

Wow! Great video and reports. Glad the mojave got enough rain for this to happen.

[dspdrew]

Update 11-11-2016
 
Not sure what happened to the nanitic that one of the captive bread queens produced, but now I'm down to only one of those that I got from Retroman, and that queen only has a couple larvae.

 

As for the queens that I tried to breed, I'm down to three of them now, two with eggs, and I still don't see any brood.

 

The queens I collected from the mating flight aren't doing all that great, but they're doing better than the others. A few of them have died, and it seems the only ones with any brood at all are the ones I have in the dirt boxes. One of them just got her first nanitic, and another should have one within a day or two.

[sgheaton]

When I stumbled on the "ant balls" I couldn't distinguish between what was queen and what what drone. It was quite terrifying to have ant balls falling on you. Unfortunately, the 6 that I captured were all drones. 

 

Would it be wise/ok to simply capture ...that mess (your video makes it clear that one ant is RED/RED and the other is RED/BLACK) of an ant pile and sort through it later? I wanted to make sure that the queen was fertilized so I kinda waited, AKA went in the library and got my stuff, then came back for collections. Wrong move there.

 

Quite a dance they do huh? Dude didn't even offer a cigarette or cab fair..

[dspdrew]

Update 11-26-2016
 
I don't have anymore of the queens that Retroman bread, and there's still no signs that any of the queens I tried to breed are fertile. I do have two colonies from the mating flight that both have workers now. One colony has two, and another has one.
 
I cleaned out the glass vase setup that I had the colony of Acromyrmex versicolor in, and got it all setup for one of these little colonies. I put the colony with two workers in it, and they immediately started digging.
 

 

 

[gcsnelling]

Sad to say but these are pretty much the results I expected from this experiment. Now you need to go find P. anzensis

[dspdrew]

Sad to say but these are pretty much the results I expected from this experiment. Now you need to go find P. anzensis

 

Haha, that's actually on my to-do list.

[gcsnelling]

That would be good, the trick will be to find it in a location that is collectable.

[dspdrew]

Yeah...

[dspdrew]

Update 11-27-2016
 
So I checked on this colony today and noticed the new nest was all closed up. It looked exactly like a closed off founding chamber.
 

 

 
At first I thought the stupid queen sealed the nest off, thinking it was digging a founding chamber, but then I checked the old nest and it was empty. I now can see the queen and both workers in the new nest. It's amazing how fast they dug it and moved in. I think the workers will probably open the nest back up once they get hungry.
 
Hopefully these will do much better in this larger setup, like Retroman says they should.

[gcsnelling]

Go get em Drew.

[dspdrew]

Update 2-28-2017
 
Apparently after three months of doing nothing, and I think eating nothing as well, the queen I put in the vase setup is actually still alive! Both workers slowly died off, so the other day I decided to move my Pogonomyrmex californicus into the vase since I assumed the queen was dead too. Well amazingly it wasn't dead, and was pulled out of it's nest and being attacked by a few of the P. californicus workers. I quickly brushed them off of it, and moved it into one of my small "dirt boxes".

[dspdrew]

Update 3-9-2017
 
This queen died shortly after being moved. I don't know if it was from being attacked, or just a coincidence. Hopefully I'll find some more this season.

[sgheaton]

Never a fun day when you start it with a "Drew Discontinued Journal"

[dspdrew]

Update 10-3-2017
 
I never found any of these this year, but like every year, Retroman bread a bunch of them in captivity and gave me quite a few fertile queens. Most of these queens were put into my dirt box setups, and so far only a hand-full are still alive. Right now I have ten of them, and only two with brood. Two still have wings and are both still being kept in test tubes.
 
I moved one queen that had a couple larvae into my giant ant farm after making the latest modifications to it.  It took a while, but it eventually started digging a new nest.
 

 

 

[dspdrew]