As of 2008, there was very little information on the indirect effects of fire on barrens dagger moth. See FEIS reviews for information on the effects of fire on larval hosts such as bear oak.
HABITAT RELATED FIRE EFFECTS: Research is needed on the effects of fire frequency, severity, timing, and continuity on barrens dagger moth habitat quality [10,14,16]. At least some communities occupied by barrens dagger moths, including pine barrens and scrub oak thickets, are maintained by fire [10,14,16]. Succession of pine barren-oak scrub to shade-tolerant hardwood species would result in a loss of barrens dagger moth habitat [16]. It is possible that burns with sprouting oaks provide quality barrens dagger moth habitat, but there are no data to support this [11,14]. Prescribed fire could be used in combination with thinning and mowing (See Habitat management) to maintain the mosaic habitat structure recommended for rare moths of the eastern United States [3,16].
Population trends: Barrens dagger moths are most abundant in the Ozarks [14] and are comparatively rare in the eastern portion of their range [3,12,14]. Populations likely experienced some decline, although the extent is uncertain due to a lack of historical information. The decline in barrens dagger moth populations has apparently slowed or ceased since the 1990s [14]. See the Schweitzer's [14] review for more detailed information on the conservation status of barrens dagger moth.
Threats: Threats to the persistence of barrens dagger moths include habitat loss, fire suppression, extensive fires, high levels of white-tailed deer (Odocoileus virginianus) browsing, introduced species, insecticides, off-road vehicles, and light pollution [9,10,14,16]. Introduced species that may negatively impact barrens dagger moth are gypsy moths (Lymantria dispar) and parasitoids such as compsilura (Compsilura concinnata) [9,10]. Spraying for mosquitoes (Culicidae) and gypsy moths could negatively impact barrens dagger moth. Since it is not as persistent as other insecticides, use of the insecticide Bacillus thuringiensis var. kurstaki in spring is recommended if severe defoliation by gypsy moths appears imminent. White-tailed deer damage may have contributed to the extirpation of the barrens dagger moth population at Pinery Park, Ontario [14]. For information on the potential impacts of fire on barrens dagger moth, see Fire Effects and Management.
Sampling: Barrens dagger moths are attracted to blacklights and in some areas will come to bait [14].
Habitat management: The following information is based on the general habitat requirements of barrens dagger moths and responses of vegetation and pine barren moths to Habitat management. These comparisons are speculative, and responses of barrens dagger moth to various Habitat management techniques were uncertain based on data available as of 2008 [10,11,14,16].
Protecting barrens dagger moth habitat is a high priority. Currently occupied habitat is important to the long-term persistence of barrens dagger moth populations [11]. The preservation of large patches of pitch pine-oak scrub vegetation is also recommended, since barrens dagger moths are associated with large habitat patches that are disturbance dependent [16] (see Fire Regime).
A habitat mosaic that varies in space and time and consists of patches ranging from bare sand to oak scrub thickets and closed-canopy pitch pine-oak forests will likely help support various life stages and species of moths [11,16]. Modeling of rare pine barren moth habitat requirements based on survey data from southeastern Massachusetts led to the recommendation that a range of successional stages be maintained and that management treatments focus on areas of about 69 to 279 acres (28-113 ha) [3].
Mowing, prescribed burning (see Fire Effects and Management), thinning, and potentially grazing can help maintain vegetation used by barrens dagger moths and assist in maintaining a habitat mosaic. Barrens dagger moths occur in an area of the Atlantic City International Airport in New Jersey that has been mowed every 1 to 2 winters since the 1940s [14,16]. Since it could result in the removal of oak scrub, mowing more than once a year would likely be detrimental [11,16]. Mowing in the summer may have negative initial results [11]. Thinning of pitch pine could benefit barrens dagger moth, since oak scrub cover would likely increase. Thinning of oaks to savanna may also benefit barrens dagger moth due to increases in oak scrub and maintenance of overstory oaks [11]. In the current landscape, cutting of vegetation followed by prescribed burning may be needed to maintain habitat structure and mimic high-severity summer fires [16]. Grazing may benefit barrens dagger moth habitat due to sprouting oak scrub. However, grazing multiple times a year would likely negatively impact barrens dagger moth habitat. In addition, grazing can introduce nonnative species [11], and the impacts of grazing in oak scrub are poorly understood [16]. Plowing and harrowing are not recommended due to slow recovery of vegetation and establishment of nonnative species [16]. No matter the treatment used, untreated refugia are recommended to provide a colonization source for treated areas [11,16].Barrens dagger moth habitat is often described as sandy, xeric, and open oak-dominated communities [9,10,11,14,16]. See Plant Communities for information on cover types occupied. Rare moths that occur in pitch pine-bear oak communities, including barrens dagger moth, were associated with early successional habitat patches in southeastern Massachusetts [3]. Barrens dagger moths have not been documented in most potential habitat, despite being relatively easy to detect (see Sampling) [14]. More detailed studies on barrens dagger moth habitat requirements are needed [10,11,14].
Landscape-scale characteristics may have greater influence on barren dagger moth habitat quality than patch- or plot-level characteristics [3]. Patches of remnant habitat occupied by barrens dagger moths are typically larger than 2,000 acres (1,000 ha) [10,14]. In models based on surveys of rare moths in a pitch pine-bear oak community in southeastern Massachusetts, barrens dagger moth was positively associated with landscapes with a high percentage of open-canopy oak scrub [3] and negatively associated (P=0.03) with mixed hardwood-conifer forest without pitch pine at the 1,120-acre (450 ha) scale. At a smaller scale (17 acres (7 ha)), barrens dagger moth was negatively associated (P=0.02) with the dispersion and interspersion of cover types [2]. Connectivity of habitat did not appear important in this study area, but connectivity was generally low [3].