Karner Blue butterfly Carly Voight

Karner Blue butterfly
Carly Voight

Insecta (Insects)
Lycaenidae (Blues, Coppers, Hairstreaks, Elfins)
State Protection
Listed as Endangered by New York State: in imminent danger of extirpation in New York. For animals, taking, importation, transportation, or possession is prohibited, except under license or permit. For plants, removal or damage without the consent of the landowner is prohibited.
Federal Protection
Listed as Endangered under the Federal Endangered Species Act
State Conservation Status Rank
Critically Imperiled in New York - Especially vulnerable to disappearing from New York due to extreme rarity or other factors; typically 5 or fewer populations or locations in New York, very few individuals, very restricted range, very few remaining acres (or miles of stream), and/or very steep declines.
Global Conservation Status Rank
Imperiled globally - The subspecies/variety is at high risk of extinction due to rarity or other factors; typically 20 or fewer populations or locations in the world, very few individuals, very restricted range, few remaining acres (or miles of stream), and/or steep declines. (The species as a whole is common globally.)


Did you know?

This species would not persist without active management in New York. The Albany Pine Bush Preserve manages for this butterfly through prescribed fire and by planting and encouraging growth of wild blue lupine.

State Ranking Justification

Even though there are about 50 subpopulations occupied each year, these cluster into about four metapopulations, or recovery units. Of the 50 subpopulations, the vast majority have fewer than 100 butterflies present. This species does not persist well if the total July brood for the metapopulation is fewer than 1,000 adults. This Federally and State-listed species is completely management dependent in New York, and is the case in most or all of the remaining portion of the range.

Short-term Trends

There are over 10,000 individuals in July during at least some years at Saratoga Airport but only three other sites are believed to contain one or two thousand individuals in the summer brood most years, which is marginal for a viable population of this species. The majority of sites contain fewer than 100 adults. However, it should be noted that the estimates not based on mark-recapture (see Gall 1985) are very unlikely to be close to the actual population size. Since the Federal Listing, this species has apparently been fairly stable in New York, but some small subpopulations have declined or increased slightly. At some sites, the current population sizes are not known.

Long-term Trends

The Albany area population has declined by over 90% from what it apparently was in the 1970s and the population was probably even higher originally. The Tonawanda, Brooklyn, and Sullivan County populations are extinct, as are the Rome and Watertown populations, if they really existed. The Warren County populations are now small remnant colonies. The decline has probably been less at Saratoga.

Conservation and Management


The threats include habitat loss, degradation, and fragmentation, fire suppression, inappropriate management of lupine (Lupinus perennis), mosquito spraying and the use of other insecticides, and browsing of lupine by herbivores, primarily deer. There is also a concern that a reduction in winter snow pack and other changes, due to climate change, threaten this species. Such threats could be of particular concern in New York, which has a warmer climate and is farther south than most of the current range for this butterfly.

Conservation Strategies and Management Practices

All occupied sites should be managed to increase the amount of lupine (Lupinus perennis) and to connect nearby demes (subpopulations). Controlling herbivores such as deer and protecting occupied sites from spraying with insecticides is also a management need.

Research Needs

The severity of mosquito spraying to larvae and adults needs to be evaluated, since aerial adulticiding for mosquitoes is more prevalent in New York than most other northern states and sometimes involves large areas.



Karner Blue butterflies can be found in extensive pine barrens, oak savannas or openings in oak woodlands, and unnatural openings such as airports and right-of-ways that contain lupine (Lupinus perennis), the sole larval food source. The original communities for some remnant populations in Saratoga and Warren Counties are unclear since there is little to suggest former pine barrens in these areas. Some recent populations have occurred in sandy old fields. The largest cluster of colonies was in the Albany-Schenectady County Pine Bush and parts of the region are still occupied, although today the largest population may very well be at Saratoga Airport where it occurs mainly on the approach zones.

Associated Ecological Communities

  • Calcareous pavement woodland (guide)
    An open canopy woodland that occurs on very shallow soils over flat, striated outcrops of calcareous bedrock (limestone and dolomite).
  • Pine barrens vernal pond (guide)
    A seasonally fluctuating pond and its associated wetlands that typically occurs in pine barrens. The water is intermittent, usually a pond in the spring but sometimes losing water through the summer to become a mostly vegetated wetland at the end of the summer. These ponds and wetlands may be small.
  • Pitch pine-oak forest (guide)
    A mixed forest that typically occurs on well-drained, sandy soils of glacial outwash plains or moraines; it also occurs on thin, rocky soils of ridgetops. The dominant trees are pitch pine mixed with one or more of the following oaks: scarlet oak, white oak, red oak, or black oak.
  • Pitch pine-scrub oak barrens (guide)
    A shrub-savanna community that occurs on well-drained, sandy soils that have developed on sand dunes, glacial till, and outwash plains.
  • Successional northern sandplain grassland (guide)
    A meadow community that occurs on open sandplains that have been cleared and plowed (for farming or development), and then abandoned. This community is usually dominated by low, dry turf of sedges and grasses less than 30 cm (12 inches) tall, and include patches of open sand and patches of soil covered with mosses and lichens.

Associated Species

  • Frosted Elfin (Callophrys irus) (guide)


New York State Distribution

Currently, the only known occupied sites are clustered in Albany, Schenectady, Saratoga, and Warren Counties and represent remnants of two or three once large metapopulations. Historically there were also specimens, or at least reports from Watertown, Tonawanda, Rome, Sullivan County, and Brooklyn (Shapiro 1974).

Global Distribution

The Karner Blue is currently found in Minnesota, Wisconsin, Michigan, northern Indiana, and New York. It has been extirpated from Illinois, Iowa, Ohio, Ontario, Pennsylvania, Massachusetts, New Hampshire, and Maine, but was reintroduced in New Hampshire and Ohio. It was falsely reported from North Carolina and Manitoba.

Identification Comments

General Description

A small, sivery blue butterfly with orange crescents on the margins of the underside of the wings. The dorsal surface of the male is all violet-blue, as compared to the dorsal surface of the female, which is dull purplish-blue near the body and turning a dull brown away from the body. The dorsal surface of the lower wings also have orange crescents along their bottom edges.

Characters Most Useful for Identification

The combination of marginal orange spots on the underside of all wings and lack of tails on the hindwings is diagnostic. The males have no orange at all above. The females have some orange on the hindwing above and, unlike the Eastern Tailed-blue (Cupido (Everes) comyntas), always have some blue near the body on upper side of all wings. Both sexes are also larger than tailed blues. Azures and silvery blues have no orange on any surface.

Best Life Stage for Proper Identification

The adult is the best life stage for identification. The larvae can be identified by an expert, but both Frosted Elfin (Callophrys irus) and Eastern Tailed-blue [Cupido (Everes) comyntas] larvae occur on lupine and are similar. The eggs can also be identified, but in part this involves context and experts.


It is unlikely to be seen more than a few yards from patches of lupine (Lupinus perennis), although wandering individuals do occur up to a mile or more away from main breeding areas.


Larvae feed only on the native lupine (Lupinus perennis) in nature. The adults take nectar from many kinds of low growing flowers, native or otherwise.

Best Time to See

The exact phenology varies from year to year and colony to colony. Those in the most open habitats tend to be about a week ahead of those in more wooded places. There are always two annual generations. The eggs overwinter and hatch, but not all at once, around the middle of April. The larvae mature mostly in late May and pupate. Adults emerge in late May to early June and are active for two to three weeks. The eggs from these adults hatch in a few days and the larvae are mostly mature in early July. Second brood adults fly for about three weeks and peak numbers usually occur for about a week in the second half of July. The eggs laid by these adults hatch the following spring.

  • Reproducing
  • Larvae present and active
  • Eggs present outside adult
  • Pupae or prepupae present

The time of year you would expect to find Karner Blue reproducing, larvae present and active, eggs present outside adult, and pupae or prepupae present in New York.

Similar Species

  • Spring Azure (Celastrina ladon)
  • Eastern Tailed-blue (Cupido comyntas)

Karner Blue Images


Karner Blue
Plebejus melissa samuelis (Nabokov, 1944)

  • Kingdom Animalia
    • Phylum Mandibulata (Mandibulates)
      • Class Insecta (Insects)
        • Order Lepidoptera (Butterflies, Skippers, and Moths)
          • Family Lycaenidae (Blues, Coppers, Hairstreaks, Elfins)


  • Lycaeides melissa samuelis Nabokov, 1944

Comments on the Classification

Some experts suspect this will prove to be a full species and the number of species in this genus is not well understood. In New York, the Karner Blue is considered a subspecies of the Melissa Blue (Plebejus melissa) because no published works have revised the taxonomy to elevate this subspecies to species status.

Additional Resources


Allen, T.J., J.P. Brock, and J. Glassberg. 2005. Caterpillars in the field and garden. Oxford University Press, New York. 232 pp.

Brock, J. P., and K. Kaufman. 2003. Butterflies of North America. Kaufman Focus Field Guides, Houghton Mifflin Company, New York, NY 284 pp.

Gall, L. F. 1985. Measuring the Size of Lepidopteran Populations. Journal of Research on the Lepidoptera. 24(2):97-116.

Givnish, T., Menges, E., and Schweitzer, D.F. 1988. Minimum area requirements for long-term conservation of the Albany Pine bush and Karenr bule butterfly. Consultants report prepared for the City of Alabny, NY, Malcom Pirnie, Inc.

Glassberg, J. 1993. Butterflies through binoculars: A field guide to butterflies in the Boston-New York-Washington region. Oxford University Press: New York. 160 pp.

Glassberg, J. 1999. Butterflies Through Binoculars: The East. Oxford University Press, New York, New York. 400 pp.

Iftner, D. C., J. A. Shuey, and J. V. Calhoun. 1992. Butterflies and Skippers of Ohio. Ohio Biological Survey Bulletin. New Series, Vol. 9, no. 1, xii + 212 pp., 40 color plates.

New York Natural Heritage Program. 2019. New York Natural Heritage Program Databases. Albany, NY.

New York State Department of Environmental Conservation. 1998. Karner blue butterfly (Lycaeides melissa samuelis) Nabokov. New York State recovery plan. Unpublished draft.

Opler, P. A., and A. D. Warren. 2002. Butterflies of North America. 2. Scientific Names List for Butterfly Species of North America, north of Mexico. C.P. Gillette Museum of Arthropod Diversity, Department of Bioagricultural Sciences and Pest Management, Colorado State University, Fort Collins, Colorado. 79 pp.

Opler, P.A. and G.O. Krizek. 1984. Butterflies East of the Great Plains, an illustrated natural history. Johns Hopkins University Press. Baltimore. 294pp.

Opler, P.A. and V. Malikul. 1992. A field guide to eastern butterflies. Houghton Mifflin, Boston, MA. 396 pp.

Schweitzer, D.F., 1994. Recovery Goals and methods for Karner Blue Butterfly populations, Chapter 20, pp.185-193 in Andow, D.A.; Baker, R.J. and Lane, C.P. (eds.) Karner Blue butterfly: a symbol of a vanishing landscape. Misc. Publ. 84-1994 Minnesota Agric. Expt. Sta., St. Paul, MN 222pp.

Schweitzer, Dale F., 1994. Prioritizing Karner Blue Butterfly Habitats for Protection Activities, Chapter 19, pp. 173-183 in Andow, D.A., R.J.Baker, and C.P. Lane (eds.) Karner blue Butterfly: a symbol of a vanishing landscape. Misc. Publ. 84-1994 Minnesota Agric. Expt. Station, Univ. of Minnesota, St. Paul, MN 222 pp.

Shapiro, A.M. 1974. Butterflies and Skippers of New York State. Search 4:1-60.

U.S. Fish and Wildlife Service (USFWS). 1992. Determination of endangered status for the Karner Blue butterfly [Lycaeides melissa samuelis]. Federal Register 59236-59244.


About This Guide

Information for this guide was last updated on: December 20, 2007

Please cite this page as:
New York Natural Heritage Program. 2019. Online Conservation Guide for Plebejus melissa samuelis. Available from: https://guides.nynhp.org/karner-blue/. Accessed May 26, 2019.

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