Fusca-group Formica of western US mountain forests (Oregon, California, Sierra Nevada). Claustral founding, like other fusca-group Formica. Prey and sugar, cold hibernation.
Work out the amounts for your colony →Calculator opened with Formica sibylla already selected: number of workers, brood, temperature. Free, no account.Calculator figures for moderate brood at 24 °C:
| WORKERS | PROTEIN | SUGAR |
|---|---|---|
| 10 | 1 fruit fly · Every 5 days | 1 drop · Every 4 days |
| 50 | 5 fruit flies · Every 4 days | 2 drops · Every 3 days |
| 150 | 4 juvenile crickets · Every 3 days | 7 drops · Every 3 days |
| 400 | ¾ medium cricket · Every 3 days | 16 drops · Every 3 days |
1 fruit fly ≈ a 2–3 mm insect; a medium cricket (1 cm) is about 50 fruit flies. 1 drop ≈ 0.05 mL.
Adjust to what you see: if food is left after 24 h, give less; if it all goes fast and the brood grows, give more.
Claustral founding: the queen lives on her reserves, do not feed her before the first workers.
From October to February, 5–10 °C.
All species · Hibernation calculator
Work out the amounts for your colony →Calculator opened with Formica sibylla already selected: number of workers, brood, temperature. Free, no account.