Karner Blue Butterfly

Karner Blue Butterfly

The Karner blue butterfly was placed on the Endangered Species List in 1979 and received final approval as a federally listed endangered speices in 1992.  While most Karner blue's live in Wisconsin, their territory extends throughout much of the Great Lakes region and in several northeastern states, including New York, Maine and New Hampshire.   Karner blues were previously found in Massachusetts, Pennsylvania, Ohio and Ontario, but are now considered extirpated (extinct) in those states.  The name Karner comes from Karner, NY, where the butterfly was first discovered in the early 1940's. 

ColoringMale Karner blue butterfly

Males are silvery or dark blue with a narrow black band.  The female is grayish brown to blue on the topside, with irregular bands of orange crescents inside the narrow black border.  The underneath of both males and females is gray with a band of orange crexcents along the edges of both wings. 

Flights

Karner Blue butterflies will have two broods or flights a year.  Eggs are laid in late summer and hatch the following spring in mid- to late April.  The first flight generally occurs between mid-May to mid-June.  The females lay their eggs on wild lupine, and these eggs become the second flight of the year, appearing in July or August.  The second brood will lay their eggs on the wild Lupine, which then litters the next years first flight.  The second flight can be up to four tiems the size fo the first flight, however the first flight butterflies tend to be larger. 

Management

To prevent the extirpation of this endangered species from our local landscape, the Forests conduct management activities to restore savannas/barrens habitats and annually monitor the status of the KBB to evaluate the effectiveness of restoration efforts.

Volunteering and Monitoring Efforts

 Volunteering

The U.S. Forest Service Baldwin/White Cloud Ranger District is looking for volunteers to assist in monitoring the Karner blue butterfly, a federally endangered species, within the Manistee National

Forest.  Volunteer participation in 2007 and 2008 was incredible. Individuals from numerous private and public partner organizations provided 281 volunteer days (~$37,000 in contributed volunteer time).  The District surpasssed its monitoring goals.  Employees and volunteers inventoried 436 acres; locating 34 new Karner blue butterfly subpopulations.  In addition, we estimated Karner blue butterfly abundance and assessed habitat conditions within 78 subpopulations covering 580 acres, and examined the influence of weather on Karner blue butterfly over wintering survivorship by collecting hourly temperature and weekly snow depth data within 20 selected subpopulations. We also conducted habitat surveys on an additional 104 acres to evaluate the effectiveness of different mechanical treatments at restoring Karner blue butterfly habitat.

Those participating in the 2007 and 2008 survey effort made an invaluable contribution to conserving the Karner blue butterfly by helping the District dramatically improve its understanding of the Karner blue butterfly’s status within the Manistee National Forest, and how to restore suitable Karner blue butterfly habitat. However, there is still much to learn if we are to prevent this species from disappearing from our local landscape. During the 2009 survey effort, the District will continue to monitor the Karner blue butterfly to determine:

  • how far designated metapopulation areas within the Manistee National Forest are from meeting recovery goals; develop a habitat suitability model for Karner blue butterflies within the Manistee National Forest;

  • identify high priority areas to target management; and evaluate the effectiveness of different management strategies for restoring Karner blue butterfly habitat.

Volunteers are needed to conduct Karner blue butterfly survey from late May to early June and from mid July to early August. There are opportunities for individuals of all skill levels to participate. Interested parties can volunteer during weekdays, for a few days, or a week or more. Reimbursement for mileage and housing is available.

Between May and August, interns will help inventory, assess habitat, and manage for a variety of endangered, threatened, and sensitive fish and wildlife species, including the Karner blue butterfly.

 

 

Monitoring

The Forests inventoried 821 acres; locating 34 new KBB subpopulations. In

addition, the Forests estimated KBB abundance and assessed habitat conditions within 78 subpopulations covering 580 acres, and examined the influence of weather on KBB over wintering survivorship by collecting hourly temperature and weekly snow depth data within 20 selected subpopulations. The Forests also conducted habitat surveys on an additional 152 acres to evaluate the effectiveness of different mechanical treatments at restoring KBB habitat.

 

Habitat Management

 

Karner blue habitat was historically associated with landscapes composed of sandy soils which supported oak and oak-pine savannahs or barrens ecosystems. It is now associated with remnant barrens and savannahs, highway and powerline rights-of-ways, gaps within forested stands, young forest stands, forest roads and trails and areas that are open and contain wild lupine.

Since 1992, hand cutting, prescribed burns, mechanical removal of vegetation (i.e., mowing, sheer cutting, masticating, bulldozing), scarification, seeding/planting, and road closures have been used to manage 886 acres of occupied and 902 acres of unoccupied KBB habitat within the four metapopulation management areas.  The objective of  these treatments is to reduce tree density and the encroachment of trees and shrubs, and promote the growth of native grasses and KBB nectar plant species, especially wild lupine - the sole food source for the KBB caterpillar.

Given that persistent KBB populations require abundant nectar sources and wild lupine, seeding/planting activities are essential for restoring suitable KBB habitat. Over the next two decades, the Forests plan to disperse seed and plant plugs to establish 5-15% cover of wild lupine and 5-15% cover of other important nectar plants within all sites occupied by the KBB.





https://www.fs.usda.gov/detail/hmnf/learning/?cid=STELPRDB5143170