Coastal Heathland Cutworm

Abagrotis benjamini Franclemont, 1955

Coastal Heathland Cutworm
Hugh D. McGuinness

Class
Insecta (Insects)
Family
Noctuidae (Owlet Moths)
State Protection
Not Listed
Not listed or protected by New York State.
Federal Protection
Not Listed
State Conservation Status Rank
S1S3
Critically Imperiled, Imperiled, or Vulnerable in New York - Conservation status is uncertain; could be especially vulnerable, very vulnerable, or vulnerable to disappearing from New York, due to rarity or other factors. More information is needed to assign either S1, S2 or S3.
Global Conservation Status Rank
G3
Vulnerable globally - At moderate risk of extinction due to rarity or other factors; typically 80 or fewer populations or locations in the world, few individuals, restricted range, few remaining acres (or miles of stream), and/or recent and widespread declines.

Summary

Did you know?

The word "cutworm" refers to the fact that the larvae of many species in this group cut vegetation near the soil surface and pull the vegetation into a tunnel or chamber underground, where they eat it safe from above-ground predators (Wagner et al. 2008).

State Ranking Justification

The coastal heathland cutworm is likely restricted to Long Island and nearby islands, where potential habitat is abundant. Five current populations are documented; two were first documented in 2007. Additional surveys are needed to better understand the status and distribution of this moth in New York State.

Short-term Trends

The short-term trend for this moth in New York State appears to be stable. At one of five populations documented in the state, moths were captured in 1995 and 2000, resulting in more than 10 adults captured over the course of the two years. Each of the other four populations were first documented in 1997 or 2007 and have not been surveyed since. Most of these populations are protected. Although several populations might be stable and potential habitat is still abundant on Long Island, it seems that the amount of suitable habitat has been considerably reduced over the past several decades due to development.

Long-term Trends

The long-term trend for this moth in New York State is unknown. There are historical records from Montauk and Orient. While there are two current populations documented from Montauk, surveys should be conducted in Orient to determine if a population still exists at that location. Although potential habitat is still abundant on Long Island, it seems that the amount of suitable habitat has been considerably reduced over the past several centuries due to development.

Conservation and Management

Threats

General threats include development, insecticide spraying, fire suppression, and excessively large fires on unprotected sites. In New York State, development of habitat seems to be the most likely threat.

Conservation Strategies and Management Practices

This moth is likely to persist if adequate habitat remains and all habitat at a site is not engulfed in a fire during the same season. The moth can occupy small (less than 100 ha) as well as large habitats, and it can travel substantial distances to colonize other suitable habitats, but nonetheless areas where this moth is documented should be evaluated to avoid additional encroachment or fragmentation by development. At some locations, periodic controlled burns or other measures might be needed to restore or maintain habitats where the moth occurs. When prescribed burns are conducted, some areas should be left unburned to provide refugia for the moth. Minimizing lighting to maintain dark sky conditions would also be beneficial.

Research Needs

Additional research is needed to document this species' host (larval food) plants and its more precise habitat needs.

Habitat

Habitat

The coastal heathland cutworm occurs in dry, sandy, open coastal plain habitats. These habitats include sandplain grasslands, coastal heathlands, and dunes (except the first dunes inland from the beach). In New York State, the moth has been found in several habitats including partially burned grasslands and shrublands, maritime dunes, maritime grasslands, maritime heathlands, and a coastal oak-heath forest.

Associated Ecological Communities

  • Coastal oak-heath forest (guide)
    A low diversity, large patch to matrix, hardwood forest that typically occurs on dry, well-drained, sandy soils of glacial outwash plains or moraines of the Atlantic Coastal Plain. The forest is usually codominated by two or more species of scarlet oak, white oak, and black oak.
  • Maritime dunes (guide)
    A community dominated by grasses and low shrubs that occurs on active and stabilized dunes along the Atlantic coast. The composition and structure of the vegetation is variable depending on stability of the dunes, amounts of sand deposition and erosion, and distance from the ocean.
  • Maritime grassland* (guide)
    A grassland community that occurs on rolling outwash plains of the glaciated portion of the Atlantic coastal plain, near the ocean and within the influence of offshore winds and salt spray.
  • Maritime heathland (guide)
    A dwarf shrubland community that occurs on rolling outwash plains and moraine of the glaciated portion of the Atlantic coastal plain, near the ocean and within the influence of onshore winds and salt spray.
  • Sea level fen* (guide)
    A wetland that occurs at the upper edge of salt marshes but is fed primarily by acidic groundwater seeping out along the upland edge. This fresh water sometimes mixes with salt or brackish water during unusually high tides. There is a high abundance of sedges that decompose slowly and create a deep substrate of peat. This peat is underlain by deep sand or gravel. These fens usually have a high diversity of herbs but may also have scattered trees and shrubs.

* probable association but not confirmed.

Range

New York State Distribution

This moth is documented from eastern Long Island and an offshore island. It is likely restricted to Long Island and nearby islands. There is a historical record from New York City (D. Schweitzer, personal communication), but no documentation.

Global Distribution

This is a very disjunct species. Its distribution extends from Cape Cod and offshore islands west to Plymouth, Masachusetts, and includes eastern Long Island and an offshore island in New York. In the early 1900s, it also included East River, Connecticut. It has also been reported from Singletons at Lakehurst (1951) and Dividing Creek (1996) in southern New Jersey, but no populations have been documented there. LaFontaine (1998) indicates that a disjunct population occurs near the mouth of the St. Lawrence River in Canada. Typical A. benjamini in western North America does not get within 2000 kilometers of the range of this subspecies.

Best Places to See

  • Montauk County Park (Suffolk County)

Identification Comments

Identifying Characteristics

Like many other noctuids (owlet moths), the coastal heathland cutworm is a small, brown moth. The forewing is reddish brown, with a white strip at the end. The hind wing is grayish brown, with darker shading towards the end. The wingspan is approximately 30-35 mm. Larvae are smooth, brownish gray to brownish black, and grow to approximately 30 mm (Crumb 1956).

Best Life Stage for Proper Identification

The adult is the best life stage for identification.

Behavior

Adults fly mostly in July, but some also fly in August and September. Larvae hatch from eggs in the fall. The larvae overwinter and continue to feed in the spring. Pupation occurs in a cell underground. Prepupal larvae of some closely related species (and perhaps this species) aestivate underground for three or four months during the summer before emerging as adult moths (Wagner et al. 2008).

Diet

The plants on which the larvae feed have not been documented.

Best Time to See

The best time to see the coastal heathland cutworm is during its flight season, from July to September. Most adults fly in July, but some also fly in August and September.

  • Present
  • Reproducing

The time of year you would expect to find Coastal Heathland Cutworm present and reproducing in New York.

Coastal Heathland Cutworm Images

Taxonomy

Coastal Heathland Cutworm
Abagrotis benjamini Franclemont, 1955

  • Kingdom Animalia
    • Phylum Arthropoda (Mandibulates)
      • Class Insecta (Insects)
        • Order Lepidoptera (Butterflies, Skippers, and Moths)
          • Family Noctuidae (Owlet Moths)

Synonyms

  • Abagrotis crumbi benjamini Franclemont, 1955
  • Abagrotis nefascia benjamini Franclemont, 1955

Comments on the Classification

This fairly minor and extremely disjunct eastern subspecies has been reported from New Jersey, New York, Connecticut, and Massachusetts. It may be a distinct species. The species Abagrotis nefascia (A. crumbi crumbi) is western and widespread, occurring from Colorado to Washington.

Additional Resources

References

Crumb, S. E. 1956. The larvae of the Phalaenidae [=Noctuidae]. U.S.D.A. Tech. Bull. No. 1135. 356 pp.

LaFontaine, J. D. 1998. Noctuoidea, Noctuidae (part). In Dominick, R.B. et al. The Moths of America North of Mexico. Fascicle 27.3. The Wedge Entomological Research Foundation. 348 pp.

NatureServe. 2010. NatureServe Explorer: An online encyclopedia of life [web application]. Version 7.1. NatureServe, Arlington, Virginia. Available http://www.natureserve.org/explorer. (Data last updated August 2010)

New York Natural Heritage Program. 2024. New York Natural Heritage Program Databases. Albany, NY.

North American Moth Photographers Group at the Mississippi Entomological Museum. No date. Mississippi State University, Mississippi. http://mothphotographersgroup.msstate.edu/MainMenu.shtml

Opler, Paul A., Kelly Lotts, and Thomas Naberhaus, coordinators. 2010. Butterflies and Moths of North America. Bozeman, MT: Big Sky Institute. <http://www.butterfliesandmoths.org/> (accessed May 2010).

Wagner, D. L., D. F. Schweitzer, J. B. Sullivan, and R. C. Reardon. 2008. Owlet Caterpillars of Eastern North America (Lepidoptera: Noctudiae)

Links

About This Guide

Information for this guide was last updated on: November 26, 2019

Please cite this page as:
New York Natural Heritage Program. 2024. Online Conservation Guide for Abagrotis benjamini. Available from: https://guides.nynhp.org/coastal-heathland-cutworm/. Accessed March 19, 2024.