Harvester Ant Care Sheet
Harvester ants (Pogonomyrmex) are the seed-eating desert ants that built ant keeping in this country. They are hardy, dramatic to watch, and they sting. This is the care we give our own colonies, from a USDA-licensed breeder.
What temperature do harvester ants need?
One warm end at 82-85°F, the other end at or near room temperature. It must be a gradient across the setup, never the whole nest heated, so the colony can move brood to the temperature it needs.
Use a heat cable. Only a heat cable. Not a heat mat, not a lamp, not a windowsill. Mats and lamps heat too broadly, which destroys the gradient, and they dry the nest out or cook it. Below 80°F at the warm end, growth stalls.
Heat is for the brood, not the ants. If your colony moves away from the cable, that is usually correct behaviour - they are placing brood where it develops best.
What do harvester ants eat?
Seeds first. This is what makes them different. A small seed mix in the outworld is their staple. They husk it, carry the kernels into the nest and build a seed cache. The discarded husks pile up in a midden - that is normal and healthy, not a mess to worry about.
Red Ant Drank stays available at all times as their carbohydrate source, on a wet cotton or PVA wick - never an open pool, because they drown in it.
For protein, offer fresh killed feeder insects only. Never frozen, never protein gel. Store-bought crickets are fine. Do not feed honey, fruit, dog food or table scraps.
Do harvester ants sting?
Yes, and it is a real sting. Handle them with tweezers, never with your hands.
Pogonomyrmex maricopa holds the record for the most potent insect venom ever measured. In practice that means a sting is genuinely painful to a careless keeper, but it is not medically dangerous under normal conditions. A rare allergic reaction is possible, as with any stinging insect. Treat them with respect rather than fear - and never let a child handle them.
How do I keep the humidity right?
Fill the test tube reservoirs with water and plug each with a PVA sponge. That is your humidity for 90 days or more, with no nest maintenance in between.
PVA over cotton, every time: cotton grows mould over the weeks a founding tube sits undisturbed, and mould is a leading killer of young colonies. Keep the water end cooler than the warm end so it does not dry out.
How fast should my harvester colony grow?
A new batch of workers every 45-60 days is the benchmark for a young colony. If that is not happening, something in heat, humidity or protein is off - get in touch and we will work through it with you.
"Nothing is happening" is usually not a problem. With very few workers, only one or two hold the forager job, so most of the colony stays in the nest where you cannot see it.
Is my colony dying, or is it just winter?
Slowing down is normal. Not moving is not, if you are above 55°F.
The reliable test: ants in diapause move slowly when disturbed. Dead ants curl up and show no movement at all, even lifted with featherweight forceps.
There is mould in the tube. What do I do?
Do not panic - ants are far hardier than people expect. Set up a fresh test tube and do a normal transfer. If the colony is already in one of our nests, swap the bad tube for a freshly set up one and leave the old tube in the outworld until it empties over a few days.
Common mistakes that kill harvester colonies
- Heating the whole nest instead of one end
- A heat mat or lamp instead of a cable
- Letting the warm end sit below 80°F
- No seed mix, or only feeder insects
- Cotton plugs left to mould through the founding stage
- Frozen feeders or protein gel
- Combining two colonies, or letting two share an outworld
- Handling them by hand. They sting.
Which harvester ants do we keep?
Pogonomyrmex barbatus (red harvester) · P. occidentalis (western harvester) · P. rugosus · P. maricopa · P. californicus.
Where can harvester ants be shipped?
Live ant shipping is restricted by state, and the approved list is per species. Each listing shows exactly which states that species can ship to - check the listing before ordering. We are a USDA-licensed breeder and we do not ship outside what we are permitted to.
Shop harvester ants
Questions about your setup? Email antopiausa@gmail.com - we would rather answer early than replace a colony later.