How to Care for Messor ebeninus | The Ebony Harvester Ant Guide

Glossy black and wonderfully robust, Messor ebeninus is a harvester ant from the warm, dry Middle East. Its name means "like ebony", and one look at the shiny queen shows you why.

Watching the workers carry seeds home and turn them into "ant bread" is a joy for children and grown-ups alike. It is relatively low-maintenance and easy to care for. This guide explains Messor ebeninus care step by step, from the day your parcel arrives to a thriving colony.

We have kept ants since 1997, and everything here comes from our own colonies and the care rules we use every day.

👉 In a hurry? Download our free Messor ebeninus care sheet (PDF) or open the Messor ebeninus care sheet page for the key facts at a glance.

Messor ebeninus at a Glance

• Origin: the Middle East, such as Syria, Israel and Lebanon

• Keeping level: Beginner

• Queen: 11 to 12mm, shiny black

• Workers: 3 to 11mm in three sizes; minors reddish black, majors shiny black

• Colony: one queen, up to about 10,000 ants, and up to 25 years

• Main food: seeds

• Nest temperature: 21 to 26°C

• Nest humidity: 65 to 75%

• Workers before moving into a nest: 10 minimum, 15 to 20 recommended

• Winter: a natural rest from late November to late February, never below 15°C

• Water: never open water, a watering test tube only

Meet the Ebony Harvester Ant

In the wild, Messor ebeninus lives in dry, warm land with sandy soil and low shrubs. It nests deep in the ground and under stones, where its stored seeds stay dry.

The workers come in three sizes, each with its own job. Minors care for the queen and the brood (the eggs, larvae and pupae), medias make "ant bread" and keep the nest clean, and the big majors guard the colony. Even the majors are workers, not a separate soldier caste.

Each colony has a single queen, who can live up to 25 years. A healthy colony can reach about 10,000 ants. Workers live 1 to 2 years: the bigger the worker, the longer it lives.

Unusually, new queens fly out at the start of winter, from late November to early December. After her flight, a queen pulls off her wings and seals herself away to raise her first workers.

When Your Ants Arrive

The most important step: leave the parcel completely unopened, exactly as it arrived, at room temperature for 5 hours. The ants must adjust to your home's temperature slowly, because abrupt temperature changes make ants seriously unwell.

After the 5 hours, check the queen is safe and sound. Then leave the colony in its original packaging, with the test tube still in its tin foil and wrapping, somewhere quiet and still, away from daily household activity. Daylight is fine, never direct sunlight.

Give the colony 4 to 5 days of complete rest. The ants were fed before dispatch, so they need nothing from you. Use this time to set up and water the nest. 👉 Our step-by-step ant farm setup guide shows you how.

Still workers or a motionless queen after delivery are almost always delivery stress. Look at the queen's antennae: moving antennae mean she is fine. Almost all recover within 4 to 5 days, and big harvester queens can take a little longer.

Inside a harvester ant test tube you will see a black divider between the two cotton stoppers. Don't remove it: it keeps the ants safe in transit, and it has a hole that the queen and workers pass through easily.

Life in the Test Tube

Keep the colony in its test tube until it has at least 10 workers. 15 to 20 is even better. Moved earlier, the workers often abandon the queen in the bigger space, and the colony can fail. The same rule applies to a queen bought on her own.

A queen on her own still needs a little food. Once a week, give her a tiny drop of protein jelly, about half a grain of rice, on a small flat piece of tin foil inside the tube, next to the dry cotton stopper.

In our experience a fed queen raises her first workers faster, and the queen and colony do far better afterwards. Keep her tube wrapped in its foil and disturb her as little as possible.

Moving Into the Ant Farm

When the colony is ready, connect the test tube to the nest with the delivery tin foil still on. Leave it like that for 14 days.

Then slide the foil back about 1mm every day until the tube is fully exposed to daylight. If the ants haven't moved 2 days later, wrap the foil back on, wait another fortnight and repeat. Moving in can take from a couple of days to 6 months.

Once the colony has moved, leave the old test tube connected for at least another 14 days, as ants sometimes leave brood behind.

The red filter and black cover stay on the nest all the time. You can lift the black cover once a day for 2 to 3 minutes, ideally at night, and take the red filter off once a week for 2 to 3 minutes. Take colony photos once a month at most.

The Best Ant Farm for Messor ebeninus

👉 Our top pick is the Angie ant farm starter kit, our harvester ant farm with a built-in digital meter. It shows the nest temperature and humidity at a glance, which matters a lot for harvesters, as too much water makes seeds sprout.

👉 The A7 Plus ant farm kit is a great choice too, also with a pre-installed digital meter. If you already have your ants, choose its Nest + Outworld option.

Place the ant farm in normal daylight, never direct sunlight. Avoid windows, radiators and heaters, vibrating surfaces, speakers and TVs, and rooms with strong smells such as the kitchen.

Temperature and Heating

Keep the nest at 21 to 26°C. Most UK homes only reach that on a few warm days a year, so harvester ants can't thrive without gentle heating.

👉 That is why we recommend the Advanced Heating System Small 4W on every harvester ant farm. Its digital thermostat holds a steady warm spot. Set it to 24°C.

On a horizontal nest such as Angie or the A7 Plus, the heat mat goes under one quarter of the nest. On a vertical nest such as Maisie, it goes under half. Always put it on the side opposite the watering area, so the ants can choose their spot.

Harvesters love a warm outworld. By day it should ideally be a little warmer than the nest, around 25 to 28°C, and it can cool to about 18°C overnight. If the nest is heated, warm the outworld too: the Small 4W can warm a small outworld as well.

Never let the colony get hot either. Above 28°C in the nest puts the queen in danger.

Water and Humidity

Keep the nest humidity at 65 to 75%. Above 75%, stored seeds start to sprout, and that causes big trouble. Use distilled or purified water only. Never use tap water, rainwater or bottled mineral water, even boiled: they cause mould and fungus.

Water the nest about once a week with the pipette provided. Pour very slowly, a drop at a time, through the watering hole. With harvesters, be extra careful: no more than 1 drop should leak into the nest. Two drops can push the humidity far too high.

With a meter, simply water when the nest humidity drops below 65%. In summer the nest may need it a little sooner, and in winter a little later.

Never water the outworld. Keep it dry, at about 50% humidity, like an average UK home.

Harvester ants must never have open water, because they can drown in it. Give them a watering test tube in the outworld, not a water dispenser. Most of the water they need comes from their seeds and other food anyway.

Feeding Your Harvester Ants

🌾 Seeds are the main food. Give our 👉 harvester ant seed mix. In our experience, about 15 seeds a fortnight is right for a colony of around 30 ants. Give more as the colony grows.

Always put the seeds on a piece of tin foil or in a 👉 small feeding dish in the outworld. Never put them straight on the substrate: damp seeds sprout, and sprouted seeds are harmful to the colony.

🥩 Once a week, for example every Monday, give a little 👉 Protein Jelly. The queen and brood need it to grow. Keep protein jelly in the fridge at all times.

🍯 Once a week on another day, for example every Thursday, give our 👉 organic ant honey or 👉 Ant Nectar, which has even more carbohydrates than honey. Both are far better than sugar water or home-made mixes.

Young colonies and lone queens lean more on protein and honey than on seeds. Feed in the outworld only, and remove leftovers after 2 days to stop mould.

Keep Mites Out of Your Colony

Blood-sucking mites are one of the biggest dangers for harvester ants, and they are not rare. They often arrive with bird seed from local shops and off-licences, dried mealworms (useless as ant food), and live food from pet shops or online, where about half carries mites.

Buy ant food only from established, reputable ant-keeping suppliers. At Best Ants UK we clean our foods in several ways before dispatch, check every colony twice a month, and check each colony again before it leaves us.

A home freezer won't kill all the mites in seeds, so never rely on it. We freeze our seeds below -60°C in a special freezer before they reach you.

Now and then, look at your queen with a magnifying glass. Tiny white or reddish specks on her joints and legs, together with ants dying fast, are a warning sign of blood-sucking mites.

Stopping Escapes

Harvesters are not famous escape artists, but every ant colony tests its outworld. Paint a band of 👉 PTFE Fluon escape barrier around the top inner edge of the outworld lid. The ants slip off it and can't climb out.

PTFE wears off as the ants keep testing the same spots. For a colony of up to about 100 ants, reapply it roughly every 4 weeks. For 300 to 500 ants or more, reapply it about every 2 weeks. Never shake the bottle; roll it gently instead.

Winter Care

Messor ebeninus has a natural winter rest from late November to late February. It doesn't need a cold hibernation, and the colony slows down anyway, because its biological clock can't be tricked.

Harvesters are sensitive to cold. 15°C is the absolute minimum, and 17°C or above is safe. When the room drops below 17°C, keep the heating system running at 24°C. Never put ants in a fridge, shed or garage, and avoid any abrupt temperature change.

Feed less in winter, but never guess. At 17 to 22°C, give about a third of the summer amount. At 22 to 26°C, give about half.

Can I Release My Harvester Ants?

No. A colony raised indoors won't survive outside. If you ever can't keep your colony any more, 👉 visit our ant adoption page and let us know. We'll see whether we can take it in.

Frequently Asked Questions | FAQ

Is Messor ebeninus good for beginners?

Yes. It is a robust, low-maintenance harvester ant that is easy to feed and lovely to watch. Get the careful watering right, keep the nest warm and give seeds on tin foil or a dish, and the colony rewards you for many years.

What do Messor ebeninus eat?

Seeds are their main food, from a harvester seed mix bought from an established ant-keeping supplier. Add Protein Jelly once a week and organic honey or Ant Nectar once a week on another day. Always feed in the outworld only.

How many workers before moving Messor ebeninus into a nest?

At least 10 workers, and 15 to 20 is even better. The same rule applies to a queen bought on her own: she stays in her test tube until she has raised enough workers.

Do Messor ebeninus need heating?

Yes, in almost every UK home. We recommend the Advanced Heating System Small set to 24°C on every harvester ant farm: under one quarter of a horizontal nest, or half of a vertical nest.

Do Messor ebeninus hibernate?

They have a natural winter rest from late November to late February, but they don't need a cold hibernation. Never let them drop below 15°C, and keep them at 17°C or above to be safe.

Why is it called the ebony harvester ant?

Ebeninus means "like ebony", the glossy black wood. The queen and the big workers are a deep, shiny black, while the smallest workers are a reddish black.

Do Messor ebeninus sting?

No. They have no sting, although the big majors can give a small pinch with their jaws. They don't spray formic acid either. As with every ant, never handle them.

Start Your Own Ebony Harvester Colony

👉 Find Messor ebeninus queens and colonies in our shop, and watch your own ebony harvesters fill their granaries with seeds.

Print this guide and keep it next to your ant farm. 👉 Keep the essentials close and explore all our free ant care sheets.