193 replies to this topic

[PurdueEntomology]

Within an hour mites start to fall off ants. Exposure though has to be monitored and limited it seems to ensure the ants are not affected detrimentally. 

[PurdueEntomology]

I have decided to release the colony this Saturday near to where they were originally collected. This will be best for them.  It has been a very fascinating venture but the colony's wellbeing trumps my personal interests.  What I have learned is this species only with difficulty can be containerized.  Probably the fact of the matter is it cannot for any extended period be housed.  The issues of mites are just one of several difficulties and issues that compromise the health of the colony I am convinced.  Though the queen is in a second egg laying cycle the current pupae are dying for some reason.  I believe that it stems from the overall stress of the colony and the issue of the mites, which I have yet to get determined as to their true nature.  With Dr. Bernards assistance we will resolve the mite question and narrow down a genus if not a species.  

[ponerinecat]

Too bad, I was hoping they would do better than last time. At least we learned a lot. On behalf of the community, thank you so much for sharing your experiences with these extraordinary ants.

[gcsnelling]

Loads of good information has been obtained, good job.

[TennesseeAnts]

Too bad, I was hoping they would do better than last time. At least we learned a lot. On behalf of the community, thank you so much for sharing your experiences with these extraordinary ants.

Indeed!

[PurdueEntomology]

Too bad, I was hoping they would do better than last time. At least we learned a lot. On behalf of the community, thank you so much for sharing your experiences with these extraordinary ants.

I am quite content with the way it has all played out.  I have learned much and been able to share.  I have been able to gather valuable information that I am sure I will be using in the future as I pursue further studies. There are so many unknowns about this group of ants, well in fact about 99% of all ants to be realistic.  The only way we learn is by engaging, even with taking them from their natural environments for these temporary periods.  I think this colony actually did better than two years ago.  The queen in this one is healthy and viable.  The workers seem to be fine save for the mites which in the end may simply be phoretic.  I would like to understand why a % of pupae have died, that is mysterious.  Right now there is a new batch of eggs and the ants are doing their nightly foraging etc so unlike the previous colony two years ago this has been a better effort. 

Loads of good information has been obtained, good job.

Thanks Gordon, I appreciate that.  I tried my best.  Some factors are just there and difficult to contend with.  

[PurdueEntomology]

Well Dr . Bernard placed the phoretic mites on and E.coli agar Petri dish and they have already developed into adults.  So now the task of figuring out what mite they are.

[PurdueEntomology]

Dr.  Bernard confirmed the mites are bacteriaphagous in nature, not ectoparasitic.

[Squidkid]

Are You still releasing the colony?

[ponerinecat]

He most likely already has.

[gcsnelling]

The mite observations would be a nice addition over at Inaturalist.

[PurdueEntomology]

The mite observations would be a nice addition over at Inaturalist.

Hmm, well let us see if we can figure out what genus and perhaps even species they are.

[PurdueEntomology]

Update:

I have NOT yet released the colony.  After seeing Dr. Bernard last week I reconsidered a release date.  Though there has been a loss of pupae it is not total and the current pupae are soon to eclose as can seen from their darkening.  The queen is no longer physogastric and a mass of eggs similar to the first batch have been laid and are being attended too, there appears to be no loss of eggs or die off of them.  The colony despite the mite load appears to be having normal activity. The question then is what could have caused a die off of pupae.  I have considered food quantities, were these pupae eaten?  I find that hard to imagine since the colony has up to date been well stocked with food-brood.  Could it have been a humidity issue?  I have no information as the proper humidity for pupal development though the colony has never been dry nor overly moist. Could it have been temperature from the heat lamp, that I am not confident in as the average surface temperature has been 82F which seems to be a safe temperature to encourage development.  I have no data from field research of preferred nest site temperatures and humidities from which to work and set my containerization parameters. Could it have been a mite issue, possibly but I have only seen a few phoretic mites on  pupae and no overall mite activity that would suggest mites feeding on pupae. Could it have been stress such as disturbances perceived by ants? That is a real possibility.  I have been reading on positive and negative mite interactions with insects, specifically phoretic mites.  Now a large phoretic mite load may stress out ants and reduce their mobility and over all normal activity and this could be a cause of  their possibly killing their own pupae, but this is pure speculation on my part.

 

UPSHOT: I am going to keep the colony through this eggs/larvae cycle and see how they develop.  Will the ants carry the larvae through and will they show previous increased activity as before with the assumed larval influences while having an increased mite load?  I feel this is an important observation though to be honest it will be hard with rigor to determine this but if I am consistent with following my previous protocols yet observe differed behavior regarding egg-larval development with the 2nd brood I may consider the new variable as the mite load. So this is where we are at.

[Squidkid]

What did it look like when You found the dead pupae? Were the rotting? Being fed upon or just thrown out of the nest? If they were not cannibalized then I would assume they were contaminated some how. I am not sure how. Maybe some unknown or unseen factor.
Humidity could be a factor. Is humidity pretty high where You live?

[PurdueEntomology]

What did it look like when You found the dead pupae? Were the rotting? Being fed upon or just thrown out of the nest? If they were not cannibalized then I would assume they were contaminated some how. I am not sure how. Maybe some unknown or unseen factor.
Humidity could be a factor. Is humidity pretty high where You live?

from what I could tell just removed and thrown out. I did not see mold or canibalizing but I will check again.  I do not think humidity is an issue as it has been between 50-80% depending on the time of day

[Squidkid]

That seems reasonable. It is probably not the issue to be honest. With just the description You have provided I would assume some other factor (parasites, contaminants) Do You provide a moisture gradient? Maybe one area that is more humid than the other?
I do not know what humidity levels they require. I am going to run some field test on a colony I am tracking. I am pretty confident that they are using mole tunnels to get around. So I am going to test those and see what readings I get. They may not be 100% to what the ants need... but it could get me in range

[PurdueEntomology]

That seems reasonable. It is probably not the issue to be honest. With just the description You have provided I would assume some other factor (parasites, contaminants) Do You provide a moisture gradient? Maybe one area that is more humid than the other?
I do not know what humidity levels they require. I am going to run some field test on a colony I am tracking. I am pretty confident that they are using mole tunnels to get around. So I am going to test those and see what readings I get. They may not be 100% to what the ants need... but it could get me in range

yes they have options

and I have re attached one container which they use as a gathering place, the colony has groups here and there

[Squidkid]

That is good. Hopefully it was just a fluke

[Canadant]

Enjoying the journal. Thanks.

[gcsnelling]

I sure wish more journals were as complete as this one.