At Risk: Sand Verbena Moth
The sand verbena moth was discovered on a few coastal beach sites on Vancouver Island, British Columbia, Canada, and Whidbey Island, in northwestern Washington, and described as a new species in 1995.
This Copablepharon moth (Family Noctuidae) is imperiled due to its rare habitat types, small number of isolated populations, extremely limited range, and known threats to its habitats. They are habitat specialists that rely on loose, well-drained soils, especially sand.
The sand verbena moth completes its entire life cycle on and around the yellow sand verbena plant (Abronia latifolia). The sand verbena moth mates on the plant, lays its eggs in the flowers, and feeds on the leaves and flowers of the plant during its developmental stages, shelters under it from early instar through pupation, and provides pollination services to it as a winged adult feeding on the flowers’ nectar.
Abronia latifolia
Sand-verbena moths are restricted to active (non-stabilized) sandy sites, coastal sand beaches, and spits. These sand substrate habitats are rare in the Pacific Northwest, and in all cases are glacially derived. Wind action at these sites provides soil disturbance that supports native vegetation, such as the regionally rare yellow sand verbena (Abronia latifolia) (Family Nyctaginaceae)—the moth’s host plant.
Sand-verbena moths persist only on sites with large, dense, flowering patches of this plant species. Adult moths nectar primarily on it and females lay eggs directly on the flowers. Specialists of well-drained and sandy soils, the larvae burrow into the soil, emerging at night to feed on both the flowers and leaves.
Copablepharon moths complete a single life cycle annually (univoltine). They are sedentary, nocturnal moths that do not stray far from their restricted habitats and host plants.
Adults are present from mid-May through early July, and usually fly during dusk and early evening. Larvae are dormant, burrowed in the sand during winter, reemerging in early spring to feed and then pupate.
Why is the Sand-Verbana Moth at Risk?
Since the species was first discovered in 1994, it has been detected at 11 sites; six in Canada and five in the United States. An endemic of Salish Sea sandy coastal sites, the sand verbena moth is known from only 10 sites; five on Vancouver Island, British Columbia, Canada, and five in Washington along the eastern edge of the Straits of Juan de Fuca (San Juan, Island, Jefferson, and Clallam Counties).
Sand-verbena moth is the only Copablepharon species known from west of the Cascades Mountains.
Substantial sea level rise combined with increased storms could inundate sand-verbena moth larvae and habitat, but projected rates of rise alone through mid-century will likely not be enough to inundate all current habitat areas. Habitat risk factors include erosion, inundation by sea water and deposit of woody debris, recreation and human use, development, and invasive plant species.
Sand verbena moths at all of these sites also likely experience some level of predation by red fox, tiger beetles and bats, or other effects from invasive animal species.
Only one of the six sites, American Camp/Cattle Point, is projected to potentially maintain enough suitable habitat for sand verbena moth to persist in the next century, while James Island will likely lose the low-lying areas to sea-level rise.
How to Help the Sand-Verbana Moth
If you see this species, please share your observation with the State of Washington using the WDFW wildlife reporting form. Providing detailed information such as a photo and exact coordinates will improve the confidence and value of this observation to WDFW species conservation and management.
Don’t disturb the dune plants of the host plant. Do participate in habitat restoration at dunes organized by scientists.
