New York Natural Heritage Program
A Prominent Moth
Heterocampa varia Walker, 1855
Insects

Threats [-]
Known threats include habitat loss due to development and fire suppression, although the threat of development for the remaining habitat on Long Island may be low. The suppression of fires in barrens and other dry places would cause a loss of habitat for the species and therefore a reduction in population size. This species requires open woodland or barrens with pitch pine and scrub oaks. Forest fires are needed, on average, every 5-10 years (Jordan et al. 2003) to maintain this type of habitat. Lack of fires will result in the succession of this community to a closed-canopy forest of tall oaks and other hardwoods (Little 1979, Jordan et al. 2003). Conversely, a fire affecting an entire occurrence could eliminate most or all life stages that are present. For this particular species, though, larger populations are strongly buffered against short-term events of all kinds by the presence of pupae deep in the soil at all times, most of which wait two or rarely three years before emerging. Thus, unlike most Lepidoptera, this species could easily withstand 100% mortality of a larval cohort (NatureServe 2010).

Conservation Strategies and Management Practices [-]
The best management strategy for this species is the management of the natural community, or habitat, where this species occurs. Maintaining the Long Island pine barrens with their full suite of plant and animal species requires frequent (every few decades) disturbance to maintain open-canopy, shrub-dominated communities and to prevent succession to a closed-canopy hardwood forest (Jordan et al. 2003). Researchers have determined that an active fire management program utilizing prescribed fire with appropriate mechanical treatments is the preferred method (Jordan et al. 2003). Researchers have also determined that the size, type, intensity, and timing of fires (pyrodiversity) needs to be evaluated for each site to maximize benefits to the natural community and the species it supports (Jordan et al. 2003). The entire occupied habitat for a population should not be burned in a single year. For example, in places where prescribed burning is used, refugia (unburned areas) are needed for many species to ensure that any life stage can survive a fire. October to May burns are preferred for this species because the moths will be pupae in the soil during the fall and spring. However, larger populations are strongly buffered against short-term events of all kinds by the presence of pupae deep in the soil at all times, most of which wait two or rarely three years before emerging.

Research Needs [-]
Additional surveys are needed with blacklight traps to determine the extent of the occurrence and locate new occurrences. This species comes to light in June and July, typically after midnight. In addition, research is needed on the response of this species to prescribed (controlled) burning and mechanical treatment to improve habitat.