How to feed Pogonomyrmex occidentalis

Pogonomyrmex occidentalis is a large harvester ant from the western US with a very painful sting. It mostly eats seeds, which it stores in the nest, plus a few insects for the brood. Sugar is only a side food.

Pogonomyrmex occidentalis foraging.
Pogonomyrmex occidentalis foraging. Photo: USFWS Mountain-Prairie, Public domain, via Wikimedia Commons
Calculate exact amounts for your colony →Based on worker count, brood and temperature. Free, no account.
Nuptial flight: June–August, after rain.Rough guide: the date varies with region and each year’s weather.

What does Pogonomyrmex occidentalis eat?

How much to feed

Guidelines for a colony with a moderate amount of brood, at 22–28 °C (72–82 °F):

WORKERSPROTEINSUGAR / 3–4 DAYSSEEDS
10 (Nanitics)1 prey item every 5 days1 drop (optional)0.1 g / week
50 (Small)3 prey items every 4 days1 drop (optional)0.3 g / week
150 (Growing)9 prey items every 7 days2 drops (optional)0.9 g / week
400 (Established)22 prey items every 7 days4 drops (optional)2.4 g / week

1 prey item = one insect the size of a fruit fly (2–3 mm). A medium cricket (1 cm) is worth about 50 prey items. 1 drop ≈ 0.05 mL. Seeds: 1 g ≈ 170 millet seeds ≈ 750 chia seeds; 1 teaspoon ≈ 4 g.

These are starting points. If food is left after 24 h, give less; if everything disappears fast and the brood grows, give more. The calculator also adjusts for brood and temperature.

Hibernation

Cool hibernation from November to March, at 5–10 °C. It is part of its cycle.

Common mistakes

FAQ

What does Pogonomyrmex occidentalis eat?

Mostly untreated seeds (millet, chia, dandelion), with a few insects for the brood.

How often should I feed it?

Seeds refreshed once a week and insects once a week; sugar is optional.

Does it need hibernation?

Yes: a cool winter rest at 5–10 °C, from November to March.

Open the calculator for Pogonomyrmex occidentalis →Feeding log, journal, growth chart and forecast, shopping list.

Amounts and timings are average guidelines, not rules. Always adjust to what you see in your own colony (leftovers, appetite, brood).