Formica adamsi

Quick Summary

• Difficulty: Expert
• Origin & Habitat: Western North America including Canada and the United States. Found in high-elevation forests above 2200m including pinyon pine, oak, juniper, mixed forests, meadows, spruce-fir forests, and dry tundra. Also found in boreal sand hills, peatland forests, savannah, and woodland ^[3][4].
• Colony Type: Temporary social parasite, queen invades host Formica colony. Part of the microgyna group with miniature queens not larger than largest workers ^[1].
• Size & Growth:
  • Queen: Miniature queens not significantly larger than largest workers, approximately 5-7mm inferred from microgyna group patterns
  • Worker: Approximately 4-7mm inferred from Formica genus patterns
  • Colony: Colony size data unavailable
  • Growth: Moderate, initial growth depends on successful host colony adoption
  • Development: Development timeline unconfirmed for this species (Temporary parasitic founding means colony establishment depends on finding and invading a suitable host colony.)
• Antkeeping:
  • Temperature: Keep at room temperature. They are adapted to cooler boreal and high-elevation habitats so they tolerate lower temperatures better than tropical species. Provide a temperature gradient allowing workers to choose their preferred zone.
  • Humidity: Typical of forest floor conditions, keep nest substrate slightly moist but not waterlogged.
  • Diapause: Yes, these are boreal ants requiring a winter hibernation period. Provide cold conditions during winter months, mimicking their natural cycle in high-elevation and northern habitats ^[3].
  • Nesting: Natural nests are under stones and logs with thatched mounds in rocky areas. In captivity, a naturalistic setup with a soil substrate works well. They do well in formicariums that allow for thatching behavior.
• Behavior: Workers are typically not aggressive but will defend the nest. As a temporary social parasite, colony dynamics are complex during the founding phase. They are moderate foragers and workers are active during warmer months. Escape risk is moderate, use standard Formica-level escape prevention. Their small size means they can squeeze through smaller gaps than larger Formica relatives.
• Common Issues: temporary parasitic founding is extremely difficult in captivity, obtaining an already-established colony is the only reliable method, finding an appropriate host colony (typically other Formica species) is required for queen introduction, hibernation is essential, colonies that don't receive proper cold period will decline and fail to produce reproductives, their boreal origin means they are sensitive to overheating, keep away from direct heat sources

Temporary Parasitic Founding

Formica adamsi is a temporary social parasite, meaning its queens cannot found colonies independently like most ants. Instead, a newly mated queen must find an established colony of a host Formica species. The queen enters the host nest, kills or displaces the host queen through combat or chemical manipulation, and then uses the host workers to raise her own brood. This 'temporary' parasitism means the colony eventually becomes self-sustaining once the parasite's own workers emerge and replace the host workers. Direct observations confirm F. adamsi alpina exhibits this temporary social parasitism behavior ^[3]. This founding method is extremely challenging to replicate in captivity, the only reliable way to keep this species is to obtain an already-established colony that has successfully completed the parasitic take-over.

Housing and Nest Setup

These ants do well in naturalistic setups that mimic their forest floor habitat. Use a formicarium with a soil substrate deep enough for the ants to create chambers and passages. Include stones or flat surfaces on top of the substrate as these ants often nest under stones in the wild. The substrate should be kept slightly moist but allow for some drying. Provide a water tube for drinking and ensure the outworld has a sugar water feeder and protein food source. Standard escape prevention measures work well, though their small size means checking for small gaps. ^[3]

Feeding and Diet

Like other Formica species, F. adamsi is omnivorous and will accept both sugar sources and protein. Offer sugar water, honey, or diluted syrup as a constant energy source. For protein, provide small insects, mealworms, crickets, or other appropriate-sized prey. In the wild, they forage for honeydew from aphids and hunt small invertebrates. Their association with Microdon hoverflies suggests they have some interaction with other nest inhabitants, but this doesn't affect their dietary needs. Feed protein regularly and keep sugar water available at all times. ^[3]

Seasonal Care and Hibernation

As a boreal species from high elevations, Formica adamsi requires a pronounced winter hibernation period. During autumn, reduce feeding and allow the colony to slow down naturally. Provide cold conditions, this can be accomplished by moving the colony to an unheated garage, basement, or refrigerator during winter. The exact duration depends on your geographic location. Do not feed during hibernation. This cold period is essential for colony health and the production of reproductives the following season. Without proper hibernation, colonies will weaken and fail to produce new queens and males. ^[3]

Unique Associations

Formica adamsi has a symbiotic relationship with Microdon hoverflies (family Syrphidae). The larvae of these flies live inside ant nests, including those of F. adamsi, where they feed on ant brood. Specifically, this species has been documented hosting Microdon cothurnatus and Microdon piperi ^[2]. This is a known commensal relationship, the hoverfly larvae typically consume only a small portion of the brood and don't significantly harm the colony. In captivity, you may occasionally see these unusual guests, though they are rarely encountered.

Frequently Asked Questions

Report an Issue

The current care sheet is based fully on literature. See inconsistencies, or something that's incorrect? Please report here, it will be resolved after review from an admin. Contributing to the blogs tab also helps providing information, to make us be able to further improve the caresheets. Thank you for your support!

References