New York Natural Heritage Program
Imperial Moth
Eacles imperialis imperialis (Drury, 1773)
Insects

Threats [-]
This species is believed to be severely impacted by pesticides and parasitoids, such as Compsilura concinnata tachinid fly (Goldstein 2010; Hedbor 2006).

This species is attracted to artificial lighting. Artificial lighting can: increase predation risk, disrupt behaviors such as feeding, flight, and reproduction, and interfere with dispersal between habitat patches. In addition, many individuals die near the light source. It is not known if the impact of artificial lighting is severe, but the impact is likely greater for small, isolated populations (Schweitzer et al. 2011).

Conservation Strategies and Management Practices [-]
Insecticide use should be avoided when possible if rare species are present. When insecticide use cannot be avoided, careful planning along with consistent rare species monitoring, can result in successful eradication of the target species without eliminating rare species. A biocontrol alternative is Bacillus thuringiensis (Btk) for some target species, such as gypsy moths. However, sensitivity to Btk varies among native species and this option should be fully researched for treatment timing and regimes and weighed with other options to have the least impact on native lepidopteran populations. Gypsy moth management should be well planned to minimize impacts to rare species when they are present. However, gypsy moths can also cause severe forest defoliation. This can lead to the starvation of larvae. The greatest impact is when defoliation occurs in consecutive years. Often, summer-feeding lepidopterans can be the most affected because they often need to feed on mature oak leaves. When they are forced to only eat the regrowth (young leaves), they tend to be undersized compared to larvae that are feeding on mature leaves (Schwietzer et al. 2011). There are two other gypsy moth biocontrols that are currently unavailable, but appear to be very effective at eliminating gypsy moths with little effect on non-target species: Gypchek (a viral preparation) and Entomophaga maimaiga (a fungus).

Minimizing lighting to maintain dark sky conditions would be beneficial. When lighting is necessary, it's best to use lights that emit red or yellow light because insects are generally not attracted to those colors. However, many sodium lights, which emit yellow light, are so bright that they do attract some insects. The best lighting appears to be low pressure sodium lights which have little effect on flying insects (Schweitzer et al. 2011).

Research Needs [-]
Additional research is needed to gain a better understanding of this species' life history and habitat needs.