Seasonal parasitism of hemlock looper (Lepidoptera: Geometridae) eggs in eastern Canada

A 2-year field study was conducted using sentinel traps to determine the seasonal distribution of the egg parasitoid (Hymenoptera) complex attacking hemlock looper, Lambdina fiscellaria (Guenee), throughout eastern Quebec and western Newfoundland. Hemlock looper populations remained low in all areas over the course of the study. Parasitism of eggs in sentinel traps was generally lower in fall than in spring. Trichogramma Westwood (Trichograrmmatidae) as well as Telenomus flavotibiae Pelletier and an unidentified species of Telenomus Haliday (Scelionidae) only parasitized eggs in the fall. Telenomus droozi Muesebeck only parasitized eggs in the spring, whereas T. coloradensis Crawford attacked eggs during both fall and spring. Telenomus coloradensis was the most abundant parasitoid species collected and was far more abundant in spring than in fall collections.