Formica pacifica

Formica pacifica is a brightly coloured species of Formica occupying the west coast of the United States and Canada. This species is a host for the temporary social parasite Formica obscuripes, and potentially more temporarily parasitic and slave raiding Formica species (J. Roth, pers. comm., 2019).

Distribution based on Regional Taxon Lists
Nearctic Region: United States.

Reproduction
Alate brood is produced after hibernation, and, in British Columbia, nuptial flights occur from July to the middle of September (on particularly warm days). Male sexuals are released first, in the early afternoon. Female alates fly soon after. Dealate queens often overwinter before laying their first eggs.

Unlike most species from the F. fusca group, Formica pacifica colonies prefer their nests moderately dry. Pupae are stored at the top of the nest, often underneath a rock or another solid surface. Larvae and eggs are usually stored deeper underground, in the additionally moistened parts of the nest.

Foraging/Diet
Formica pacifica collects honeydew. These ants are also scavengers, primarily collecting dead arthropods. Dead, dried out worms are collected in particularly high numbers. Foraging activity primarily occurs in the daytime, with the peak amount of workers dispatched in the afternoon. These ants generally forage alone, but will form trails to plants containing aphids. Once food is found, workers will often recruit others to help feed, or pull food back to the nest.

Association with Other Organisms
This species is a host for the temporary parasite in British Columbia, Canada (J. Roth, pers. comm., 2019) and is enslaved by  (Trager, 2013; de la Mora et al., 2021).

Nomenclature

 *  pacifica. Formica pacifica Francoeur, 1973: 131, figs. 190-197 (w.q.) U.S.A.

References based on Global Ant Biodiversity Informatics

 * Blacker, N.C. 1992. Some Ants from Southern Vancouver Island, British Columbia. J. Entomol. Soc. Bri. Columbia 89:3-12.
 * Blacker, N.C. 1992. Some ants (Hymenoptera: Formicidae) from Southern Vancouver Island, British Columbia. Journal of the Entomological Society of British Columbia 89:3-12
 * Francoeur. A. 1973. Revision taxonomique des especes nearctiques du group fusca, genre Formica. Memoires de la Societe Entomologique du Quebec 3: 1-316.
 * Johnson R. Personnal Database. Accessed on February 5th 2014 at http://www.asu.edu/clas/sirgtools/resources.htm
 * Longino, J.T. 2010. Personal Communication. Longino Collection Database
 * Parson G. L., G Cassis, A. R. Moldenke, J. D. Lattin, N. H. Anderson, J. C. Miller, P. Hammond, T. Schowalter. 1991. Invertebrates of the H.J. Andrews Experimental Forest, western Cascade Range, Oregon. V: An annotated list of insects and other arthropods. Gen. Tech. Rep. PNW-GTR-290. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station. 168 p.
 * Ward P. S. 2005. A synoptic review of the ants of California (Hymenoptera: Formicidae). Zootaxa 936: 1-68.