ABOUT BOM SPECIES LIST BUTTERFLY HISTORY PIONEER LEPIDOPTERISTS METHODS
The Butterflies of Massachusetts
80 Columbine Duskywing Erynnis lucilius (Scudder and Burgess, 1870)
79 Mottled Duskywing Erynnis martialis (Scudder, 1869)
Columbine Duskywing may well be extirpated in Massachusetts--- but as Dale Schweitzer put it in the 1986-90 MAS Atlas, it is” not implausible that the species hangs on here in small populations in the Holyoke range and other localities where the foodplant is abundant.”
Scudder correctly distinguished Columbine Duskywing from Persius Duskywing/Wild Indigo Duskywing (Schweitzer, MAS Atlas). The latter two species were confused until the 1930’s. Schweitzer believes that “The old specimens in the MCZ (and elsewhere) from localities such as South Hadley, North Leverett, Mt. Toby, Montague, Deerfield, and Granby are probably correctly labeled as this species. Specimens from Waltham, Malden and Milton also appear to be lucilius, but have not been carefully checked for wing hairs” (MAS Atlas).
But many of the localities for lucilius which Scudder listed in his published work (1899: 1463) -- for example Amherst, Andover, Boston area, Princeton, Springfield, and Cape Cod (Woods Hole) -- relied on the reports of other collectors, and many are likely to have been wrong . The most likely of Scudder’s locations to have been correct is “the top of the Holyoke Range,” where he says it had been captured by several collectors.
Similarly, it is hard to believe that Farquhar’s long 1934 list of "lucilius" locations --which added Salem, Marblehead, Middleton, Manchester, Stoneham, Deerfield, Worcester, Sunderland, Mt. Toby, and Phillipston to Scudder’s list -- can all have been correct. Even less likely to be correct are W. P. Rogers’ 1935, 1936 and 1942 “lucilius” specimens from Fall River, Westport and Bourne (Yale Peabody Museum). Jones and Kimball (1943) do not list Columbine Duskywing for Martha’s Vineyard or Nantucket; the only duskywing they find present on the islands is Wild Indigo.
Most authorities agree that at least some of these eastern Massachusetts and Holyoke Range locations may have been correct, and that Columbine Duskywing has declined precipitously in Massachusetts in the last 100 years. Decline of this species appears to have coincided with the increase of Wild Indigo Duskywing, but it is not known if there is a connection (NatureServe 2012).
Columbine Duskywing cannot be reliably identified simply through binoculars. But descriptions may be found in Cech 2005, Layberry 1998, and MAS Atlas (Schweitzer). Many writers recommend identification via host plant association and habitat, but as Cech points out, this is unreliable because Wild Indigo Duskywings have been known to reproduce on garden columbine, and also the Columbine Duskywing may have adopted introduced crown vetch, as has Wild Indigo Duskywing.
Host Plants and Habitat:
The sole larval host plant is eastern red columbine, Aquilegia canadensis. The 1995-96 Connecticut Atlas found it in the wild on this plant (see photos in O’Donnell et al. 2007).
This lovely plant is native to, and found in, every county in Massachusetts, including the islands (Sorrie and Somers 1999). The plant is fairly common, but is probably abundant in only a few locations in the western part of the state. Abundance of the larval host plant may be important for the persistence of Columbine Duskywings at a location. Deer browse on this plant is a threat.
The main habitat is rocky deciduous woodlands. The host plants and the butterfly are often found on exposed rocky outcrops associated with limestone, but also sometimes in ravines or gullies, especially below limestone cliffs.
Relative Abundance Today
Columbine Duskywing was not found during the 1986-90 MAS Atlas project, despite a concerted effort by C. Leahy and B. Sorrie to check the most promising columbine localities in the state at the proper flight time. Dale Schweitzer failed to find it despite serious attempts in Franklin and Hampshire counties in the 1970s. In this, as in some other cases, the presence of the host plant and seemingly good habitat does not guarantee the presence of the butterfly.
MBC has no records of Columbine Duskywing, though a few searches have been made.
As Benner (2010) points out, the most likely location for this species today is the same as that mentioned by Scudder one hundred years ago: “the top of the Holyoke Range.” The species occurs just south of Massachusetts in Canaan, Connecticut, in a limestone quarry area, and the trap-rock ridge habitat there also extends into Massachusetts in the Holyoke Range.
Broods and Flight Period
Columbine Duskywing has as least two and possibly three broods in the northeast (Schweitzer, 1986-90 Atlas; Layberry 1998). Scudder, who studied this species’ life history in the northeast carefully, reported May-June for the first flight; mid-July to mid-August for the second, and late August to September for a partial third brood.
These dates are similar to those for the Wild Indigo Duskywing, for which three generations are more solidly documented (e.g. in Connecticut). The 1995-99 Connecticut Atlas reports only two generations for Columbine Duskywing (O’Donnell et al. 2007).
Outlook
Columbine Duskywing is found only in northeastern United States and Canada, and is declining or has disappeared around the southern and eastern edges of its range. While it is not known to be declining in upper Great Lakes states or in Canada, it is ranked S1 or “critically imperiled” in New Hampshire, Connecticut and Pennsylvania, is possibly extirpated in Massachusetts, and is not known to occur in Maine. In Kentucky, West Virginia and Virginia there is a small mid-Appalachian population which is disjunct from northeastern populations; the species is ranked S2 or “imperiled” in these states. Columbine Duskywing is “apparantly secure” only in New York, Michigan, Quebec and Ontario. (NatureServe 2/2012)
The 2002-2007 Vermont Butterfly Survey found only two records of Columbine Duskywing (1 voucher, 1 sight), as well as two historical records, and determined that the species was “very rare” in the state. All records were found west of the Green Mountains (McFarlane and Zahendra 2010).
Connecticut may hold the last viable populations of Columbine Duskywing in New England. The 1995-99 Connecticut Atlas (O’Donnell et al. 2007) found only 4 records at two separate locations, compared to 18 pre-project records. But there may be other undiscovered locations on trap rock ridges. The species is ranked S1 in the state, and state-listed as an Endangered Species. Benner (2010) reports that limestone quarrying is taking place at the Canaan location, potentially posing a threat to this species.
Climate warming may negatively affect this species, whereas the Wild Indigo Duskywing, with a range throughout the southern states, may be more warming-adapted.
79 Mottled Duskywing Erynnis martialis (Scudder, 1869)
Mottled Duskywing has apparently been extirpated from Massachusetts, despite a plethora of historical records. . No individuals were found during the Atlas period or subsequently, and there are no MBC records. It is also apparently extirpated from Connecticut. It was not found during the 1995-99 Connecticut Atlas, and the last records are from 1942 (Schweitzer, MAS Atlas; O’Donnell et al. 2007).
Once found throughout eastern United States, it is now sharply declining and gone from most of its northeastern range. It survived in serpentine barrens in Pennsylvania until about 1996, and can still be found in the Albany pine barrens and a few other places in New York (NatureServe 2/2012; map, Cech and Tudor 2005).
This duskywing can be identified with a good view through binoculars (e.g. Cech and Tudor 2005). Identifications in historical materials are somewhat less problematic than they are in the cases of Persius Duskywing, Columbine Duskywing, and Wild Indigo Duskywing.
Mottled Duskywing's sole host plant is New Jersey Tea, Ceanothus americanus, an attractive sand plain shrub which has probably also seen decline, owing to a combination of development, natural succession and deer browse.
Large patches of New Jersey Tea seem necessary to support the butterfly. The habitat is sand plains, pine barrens, and oak savannas. According to Schweitzer (MAS 1986-90 Atlas) the Montague Plains in Franklin County is today one of the few places in Massachusetts that seems ideal for this species. But it was not found there during Schweitzer’s extensive searches in the 1970’s, nor has it been found subsequently.
Historical records for this species in Massachusetts are legion. But given the difficulty of identifying duskywings generally, especially in the 19th century, not all of these reports can be relied upon. Scudder (1889: 1497) reported records from Andover (Scudder), Waltham (“abundant”) (Scudder), West Roxbury (Minot), and Tewksbury (Alcott) in the east, and South Hadley, Amherst (Sprague), Amherst Notch (Scudder), and Springfield (Emery) in the west.
D. W. Farquhar (1934) reports even more locations, adding Amherst again (H. H. Shepard) and Granby (F. H. Sprague) in the west, and Milton (Blue Hills) (H. H. Newcomb), Marblehead (F. H. Walker), Salem (F. H. Walker), Melrose (Gypsy Moth Lab), Ayer (Gypsy Moth Lab), and Stoneham (C. V. Blackburn) in the eastern part of the state. At Yale Peabody Museum there is even a specimen from a “boggy field” in Acton Center, 1962 (C. G. Oliver) which is labelled “martialis,” though this identification seems quite unlikely to be correct.
If even some of these records are correct, they suggest that Mottled Duskywing was present in the Connecticut River valley as well as around and north of Boston until the mid-20th century.
Outlook
Mottled Duskywing’s global status is S3 or “vulnerable.” It occurs only in eastern North America, but is not particularly common anywhere. Its accepted range is from Canada to Texas but there are currently no states or provinces where its status is secure; it is vulnerable or imperiled even in North Carolina, Georgia, Kentucky and West Virginia (NatureServe 2/2012).
Habitat and host plant threats come from out-of-control deer, gypsy moth spraying, and in some areas excessive burning. Many sandplain barrens habitats are susceptible to natural succession without management. This butterfly is a specialized, monophageous species, and is probably gone from Massachusetts.
© Sharon Stichter 2012
page updated 2-20-2012
ABOUT BOM SPECIES LIST BUTTERFLY HISTORY PIONEER LEPIDOPTERISTS METHODS