Isopods: Money Pit or Misunderstood?

[Arthroverts]

Hello all, as almost anybody who has kept isopods long-term can attest, things seem to happen where a colony or small culture is chugging along, by all accounts perfectly happy and healthy, when all of a sudden, for no apparent reason, specimens start dying off and in days an enthusiast is left with a few specimens and a lot of money down the drain.

This is something I have heard happening to multiple isopod enthusiasts, and though many can be traced back to some improper husbandry method, there are also many that can't.
Which is why I ask: why?

What is it with isopod colonies that makes them so prone to sudden and often dramatic crashes? Millipedes, often kept similarly and with a similar lifestyle in general, don't seem to have nearly as many reported "random" deaths and die-offs, or at least not such dramatic crashes without findable causes. Myself and @u bada have speculated that it has something to do with isopods being so closely tied in to endemic microfauna populations that moving them into the relatively sterile enclosures we often provide can create problems long-term, but that is just a theory.

I'm interested to hear everyone's thoughts; for those of you who experienced crashes, what happened and what was your care like at the time? Did anything alleviate the problem? To those who haven't, what are you doing that might be different from the rest of us?
It may just be consistent husbandry mistakes (that has caused plenty of my own specimen's demise unfortunately), and if so I'm eager to learn what a lot of us are doing wrong.

Thanks,

Arthroverts

 

[moricollins]

Hello all, as anybody who has kept isopods can attest, things seem to happen where a colony or small culture is chugging along, by all accounts perfectly happy and healthy, when all of a sudden, for no apparent reason, specimens start dying off and in days an enthusiast is left with a few specimens and a lot of money down the drain.

This is something I have heard happening to multiple isopod enthusiasts, and though many can be traced back to some improper husbandry method, there are also many that can't.
Which is why I ask: why?

What is it with isopod colonies that makes them so prone to sudden and often dramatic crashes? Millipedes, often kept similarly and with a similar lifestyle in general, don't seem to have nearly as many reported "random" deaths and die-offs, or at least not such dramatic crashes without findable causes. Myself and @u bada have speculated that it has something to do with isopods being so closely tied in to endemic microfauna populations that moving them into the relatively sterile enclosures we often provide can create problems long-term, but that is just a theory.

I'm interested to hear everyone's thoughts; for those of you who experienced crashes, what happened and what was your care like at the time? Did anything alleviate the problem? To those who haven't, what are you doing that might be different from the rest of us?
It may just be consistent husbandry mistakes (that has caused plenty of my own specimen's demise unfortunately), and if so I'm eager to learn what a lot of us are doing wrong.

Thanks,

Arthroverts

I haven't had a culture crash on the 15 months that I've been keeping isopods.

I have 25-30 bins of Isopods on the go right now.

I don't tend to worry about sterilizing things too much when I put them in. I bake the bark I use but the soil just goes in as is. All my cultures have mites, but I don't worry about it much.

I'm interested to see what others say.

 

[Hisserdude]

Never had culture crashes that were unrelated to lapses in care, big husbandry mistakes or the ambient temps rising above 75F°...

 

[paumotu]

The idea that it could be microfauna linked is interesting, but I doubt that so many of the species commonly reported to “randomly die off” could possibly have been cultured for so long without any known method of reintroducing these microbes. Especially when lots of the species in question have been In culture successfully for 5+ years without issue and only a certain keeper experiences problems. To me the microbe theory just doesn’t add up in this regard. Please do tell me if there’s something I’m missing though, I’m curious about what others think about this side of the issue.

 

[MantidMaster]

From my experience, isopods are rather prolific, given that you follow their requirements strictly and with care. I remember crashing my P. hoffmanseggi colony when I assumed “yeah, that’s enough ventilation” with a Sterilite box. Thankfully, I’m doing better with my other cultures, but it’s really up to strictly following their care guidelines and not missing steps. Always pay heed to the care requirements of the isopod species.

 

[BepopCola]

Do you think crashes could happen more often after x-number of generations? I'm planning to add in new genes to my colonies eventually, just in case.

I like the microfauna idea,
I have a colony of Porcellio dilatatus that took a dip over a few months, but I added in some unsterilized branches and they've perked up again.

 

[schmiggle]

I tend to find isopods in the wild in drier microhabitats than the ones in which I find millipedes. I'm sure that's not universal, but in general I would imagine that this pre-adapts millipedes to being kept in sterilite containers better than it does isopods. I think the idea of genetic crashes has a lot of merit, especially since people tend to buy pretty small initial starter colonies and don't necessarily trade individuals with others keeping the same species. Genetic bottlenecks are a big problem.

I'd also suggest that a colony that appears to be happy could in fact be suffering in a way that isn't apparent. For example, if an isopod contracted a disease of its internal organs, it would probably look pretty much the same until it suddenly keeled over.

Generally, wild microhabitats at a small distance from each other have extremely varied microbial populations even if their measured physical-chemical parameters are identical, so there's very little chance that isopods depend on specific species of micro-organism given that the range of every isopod is larger than a few square meters. It is possible that the guild of microfauna that they need is dependent on husbandry parameters that the isopods themselves aren't, in which case taking pretty much any old piece of organic material from outside and adding it to the enclosure, along with making sure that those parameters are met (whatever they are), should solve the problem.

 

[paumotu]

I tend to find isopods in the wild in drier microhabitats than the ones in which I find millipedes. I'm sure that's not universal, but in general I would imagine that this pre-adapts millipedes to being kept in sterilite containers better than it does isopods. I think the idea of genetic crashes has a lot of merit, especially since people tend to buy pretty small initial starter colonies and don't necessarily trade individuals with others keeping the same species. Genetic bottlenecks are a big problem.

I'd also suggest that a colony that appears to be happy could in fact be suffering in a way that isn't apparent. For example, if an isopod contracted a disease of its internal organs, it would probably look pretty much the same until it suddenly keeled over.

Generally, wild microhabitats at a small distance from each other have extremely varied microbial populations even if their measured physical-chemical parameters are identical, so there's very little chance that isopods depend on specific species of micro-organism given that the range of every isopod is larger than a few square meters. It is possible that the guild of microfauna that they need is dependent on husbandry parameters that the isopods themselves aren't, in which case taking pretty much any old piece of organic material from outside and adding it to the enclosure, along with making sure that those parameters are met (whatever they are), should solve the problem.

If the genes of isopods are anything like roaches, I wouldn't worry too much about any issues with a genetic bottleneck. Not saying the idea has NO merit, but I feel like genetic problems are probably the last thing people should blame after a colony crash. The idea of disease is interesting though.

 

[Hisserdude]

Do you think crashes could happen more often after x-number of generations? I'm planning to add in new genes to my colonies eventually, just in case.

I think the idea of genetic crashes has a lot of merit, especially since people tend to buy pretty small initial starter colonies and don't necessarily trade individuals with others keeping the same species. Genetic bottlenecks are a big problem.

In my experience, if anything they just get easier with each generation... The only real effect inbreeding has on most isopods is increasing the chances of odd mutations (morphs) popping up as years go by... Which most people would say is a good thing.

For example, I had an Oniscus asellus colony I started with less than a dozen individuals. The colony went on and thrived for five years without any introductions of new bloodlines, and in the last year or so I started getting Dalmatian and other interesting morphs popping up, which is where the Oniscus asellus "Mardi Gras Dalmatian" morph came from.
That morph is doing well and thriving in the hobby, despite coming from an inbred colony, and the morph had even less genetic diversity to start out with since it was started with even fewer individuals than the parent culture was started out with. Yet I had hundreds in my dalmatian culture by the time I decided to take a break from the hobby and get rid of my cultures.

 

[Hisserdude]

I've noticed a lot of people will have colony crashes happen during the summer, which seems to me to suggest they're due to rises in temperature, which are fatal especially to larger individuals, with younger individuals being the last to die.

 

[The Snark]

@schmiggle Informative.
Up in the Pacific northwest along the ocean it is pretty much wall to wall 'sow bugs'. Between them and dry rot wood seems to simply melt away. But very often a mass die off simply happens. A windowsill covered with dead bodies is typical. When a neighbor was renovating the foundations of his house we found several million dead literally raining out of some space or pocket in the damaged wood.
Found this which could explain some things: " Sowbugs and millipedes often die quickly inside homes. If sowbugs or millipedes are frequently found alive, it means there is excess moisture indoors." But a study done by HSU also found die offs if there is excess moisture due to competition from micro-organisms. So they have an envelope that has to be maintained for them to thrive.

 

[Jimbob]

I've recently had this happen with my P. Ornatus. They were being kept same as my P. Hoffmannseggi. Ornatus until then were some of my most prolific and hardy isopods. Had well over a hundred at one point. Within idk how long, maybe a week or two, the entire colony died off. My hoffs on the other hand have been thriving in their bin set up exactly the same. Temps may be a bit warmer, but they did well in warm temps last year. Only thing I can think of is I overwatered a bit, but I've done that in the past and never wiped out the whole colony. They still had dry areas.

A few of my other species have seemed to struggle too like the powdery blue/orange, but that may be for a few reasons. Neglected them a bit and I think gave them too much moisture. Still not an entire crash though.

Zebras have been pretty hardy, but an isopod that's truly stood up to everything for me is porcellio dilatatus. I've had them thrive in almost every condition you could think of. Makes them my favorite bioactive cleaner for reptiles.

 

[triffeh]

I've had cycles where a colony loses a lot of individuals but luckily I've never had a dieoff so bad they couldn't reestablish. For this reason I never have a single colony of a variety anymore - as soon as a colony can be split into two tubs I do so. I keep two colonies of most of the varieties and more of the orange P. scabers and dwarf purples since they're my favorites for adding to bioactive enclosures.
Now, since I started doing that I haven't had any more dieoffs, but I'm pretty sure that's just my husbandry improving with experience. Still, it's some peace of mind and doesn't cost anything but space and sterilite tubs.