Formica aserva (Blood-Red Field Ants)
Formica aserva (Blood-Red Field Ants)
Formica aserva (Blood-Red Field Ants)
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Formica aserva (Blood-Red Field Ants)

Canada Ant Colony
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*Also includes Formica rubicunda, subintegra, wheelerii, and other Formica sanguinea group species

Formica aserva is one of my favourite native species. They're found across Canada, and can be frequently found in raiding columns stretching hundreds of meters. As you watch the ants march by, you notice they're all carrying pupae, larvae, and other brood. Most people think "Oh they're moving to a new place" but often this could not be farther from the truth. If you follow them back to home base, you'll see a mix of red ants and black ants. Make no mistake, those black ants are slaves.

Formica aserva is dulotic, meaning it is a slave raider. These ants scout out the nests of Formica subsericea, F. podzolica, and other related species, before charging in to steal the brood which the resident colony is unable to evacuate.

Populations of this species differ across Canada in their behaviour. In places with lots of host colonies, they will often require slaves and have colonies of over 90% slave workers. In more isolated areas, they can even become non-parasitic altogether. However, having access to slaves is almost universally better than not.

Deception is an integral part of this species's strategy, and the host Formica ants will revolt and eat the brood if they find out they're in the nest of the invader. The first biological workers will likely be dark, and mainly care for the brood. This seems to calm the hosts down as well.

Formica aserva are a large parasitic variety of Formica which live in throughout Canada. They're have red head and thoraxes, with shint black abdomens. These are larger than most Formica with queens from 8-10 mm and workers from 6-10 mm. They grow large colonies up to 15,000 workers in just 3 years. They prefer 22-26 Celsius and like around 50% humidity, though there is slight variation across species. They're more skittish than most ants, and so are of medium difficulty to start, but are extremely enthusiastic and fast growing once they break 50 workers. In the wild, Formica are some of the most dominant ants, hunting down other species and consuming large amounts of biomass. We get many of these each year, though the numbers are variable. Note that this species requires good ventilation, or their formic acid spray may become an issue.

Photo courtesy of athleva

Test tube inserts are upgrades to the test tube setups provided. If purchased, they come with a dark hood to lower light levels for the colony, an insert which provides a living space, and a feeding insert to provide food for the colony.

Ungrouted inserts are a blank plastic insert which helps provide a more suitable space for the ants to grip (as opposed to glass tubes), while grouted inserts are bedded with a substrate which helps distribute humidity more evenly throughout the test tube, and helps certain ants create their cocoons more easily. Overall, grouted inserts are more comfortable for the ants.

You will NOT need an insert for colonies in test tubes, but it does help for certain species. IF you are moving the ants into a nest immediately, do NOT get a test tube insert.


Hey! This is a live product. If you are purchasing ants during the winter months, please remember to purchase the "Winter Shipping (Live Guarantee) (72 hour heat pack + 1 inch foam cushion)" in order to guarantee the order. 

Live Guarantee Policy

If live insects arrive cold or flooded please handle with care. Many of these colonies typically pop back up within a few hours. All DOA claims must be made within 24 hours after receiving your insects. Any order with a unacceptable mortality rate, but with a viable colony (e.g. less workers than in the range advertised, less queens or workers than advertised) can be compensated with store credit equal to the loss of value in the shipment, including shipping and extra packaging. Any order with DOAs, but which do not fall out of the initially advertised/promised range of workers will NOT be compensated.

DOA claims which are a total loss will be re-shipped 1 more time FREE of charge with photographic evidence. Orders where shipping is more than 30% of the total value of the order will be refunded proportionally to the loss of value in the shipment, INCLUDING test tube inserts which are purchased with the colony.

We guarantee live arrival on Xpresspost and priority shipments, as well as pickup and local delivery. Only orders that are accepted on the first delivery attempt will be eligible for DOA credit, no exceptions.

Live guarantee is VOID if you choose expedited shipping. In the winter, it is VOID if no extra packing is purchased. Fertility guarantee claims or live guarantee claims made within the month after arrival must be made with a timestamped photo of BOTH the queen alive upon arrival AND a timestamped photo of the dead specimens.

Expedited shipping can be a budget friendly method but does not always have the best results. If your order is going to be in transit more than 3 business days please do not choose this method or choose at your own risk.


Please note that orders to outdoor community mail boxes, or other outdoor locations void our live guarantee. If your address consists of an outdoor mail box or location, please make arrangements to have the order delivered to a friends house, or to your place of employment.


Just a warning, we will NOT ship live ants into the US unless the receiver has a permit. If such an order is made, it will be refunded, minus a 10% processing fee and restocking fee

This product is from Canada Ant Colony. The full catalogue, including all variants, can be found at



Thank you to Jerry from Insect Supplies Canada for letting us use his photos!