They may be smaller (.125" or 3mm), but they have numbers.

There are 52 ant species recognized in Manitoba. These 52 species are represented in three subfamilies: Myrmicinae, Dolichoderinae and Formicinae. The subfamily Myrmicinae has ten species consisting of the three genera Myrmica, Solenopsis and Leptothorax. Dolichoderinae subfamily consists of three species of ants that belongs two genera Dolichoderus and Tapinoma. The subfamily Formicinae is represented by 23 species that belongs to genus Formica.

This battle happens to be on the underside of a rhubarb leaf; the remnants of a recent, yummy harvest.