[Ant Control] Which Ants Are Bugging Canadian PMPs?

Editor’s note: This article originally appeared in the Pest Control Canada e-newsletter, sponsored by Univar Environmental Sciences. To receive this e-newsletter, email jdorsch@giemedia.com with the subject line “subscribe Canada.”
 

Ants were collected by pest management professionals across Canada during 2011 in a project funded by Orkin Canada. PMPs were requested to collect and submit samples for identification. In addition, a collection trip was made through British Columbia with Orkin Canada personnel. Collections on this trip were made at disturbed sites and residential areas. A total of 346 samples were collected from nine provinces: Alberta (3); British Columbia (207); Manitoba (22); New Brunswick (19); Newfoundland (3); Nova Scotia (2); Ontario (88); Quebec (1); and Saskatchewan (1).

Additional sampling is needed to identify ants from provinces where fewer collections were made. In visiting with personnel at the Canadian Pest Management Conference at Vancouver in March 2011, many PMPs indicated species that were not included in the list.

What We Found. The most common pest ants in the samples included:

• Carpenter ants (five species of Camponotus) in 56 samples: five out of nine provinces.
• Moisture (or cornfield) ants (five species of Lasius) in 70 samples: six out of nine provinces.
• Thatching ants (17 species of Formica) in 70 samples: seven out of nine provinces.
• Pavement ants (Tetramorium caespitum) in 44 samples: three out of nine provinces.

The European red fire ant (Myrmica rubra) was submitted from five sites in Ontario. After the previous counts were made, personal communication with Robert Higgins, Thompson Rivers University, indicated another four sites in British Columbia for the European red fire ant. This ant also has been reported in New Foundland and Prince Edward Island in a survey completed by the University of Maine. Additional samples are needed to update the information on this important pest species, introduced from Europe and seemingly spreading into urban areas. It is an invasive species that swarms when disturbed and stings.

Another myrmicine ant (Manica hunteri) was collected at 13 sites in British Columbia. This is another stinging ant that was found next to foundations and at doorsteps of residential areas and garages. It has not been reported as a pest or nuisance ant, however it is described as “not aggressive, but will sting promptly.”

The velvety tree ant (pine tree ant) was collected at six sites in British Columbia. This ant is only known in western provinces of Canada and western states in the United States. It is an important ant to the pest management industry because it is a wood-destroying ant. It will excavate wood similar to carpenter ant excavations. However, the wood that is excavated is very fine. The colonies are extremely large and very mobile. This ant also nests in and excavates foam insulation.

Ants found in samples that were not expected included the ghost ant (Tapinoma melanocephalum), ponerine ants (three provinces) and acrobat ants.

Other nuisance ants included Pharaoh ants, thief ants, odorous house ants and small honey ants. In these samples across Canada, 47 different species were identified. Some ant species are common around structures, some are not. Identification keys to the ant genus, Formica, are cumbersome and in need of revision. Many people working with this genus group the ants into seven major Formica groups. These ants are not usually problematic around structures and are important foragers on other insects; however, some make piles of unsightly thatch in yards, bite and irritate homeowners.

The author is professor of entomology, Spokane Falls Community College, Spokane, Wash. Email her at lhansen@giemedia.com.

Want to Help?
This Canadian ant survey is definitely incomplete and many areas were not sampled adequately. If you are a Canadian PMP and are interested in participating in this survey, send samples to Dr. Laurel D. Hansen, Biology Department MS 3280, Spokane Falls Community College, 3410 W Fort Wright Drive, Spokane, WA 99224.