the karner blue butterfly became endangered in 1992.
the karner blue butterfly became endangered in 1992.
when did the karner blue butterfly become endangered?
1992
the karner blue ("plebejus melissa samuelis") is an endangered subspecies of small blue butterfly which was once found in significant numbers in miller beach, now part of the indiana dunes national park. the butterfly is now mainly found in other parts of the great lakes states, such as wisconsin and michigan, in small areas of new jersey, and also in southern new hampshire, and the capital district region of new york. the butterfly, whose life cycle depends on the wild blue lupine flower ("lupinus perennis"), was classified as an endangered species in 1992. in may 2000, the canadian species at risk act listed the karner blue as being locally extinct in canada. this subspecies of "plebejus melissa" was first identified and described by novelist vladimir nabokov. the name originates from karner, new york (located half-way between albany and schenectady) in the albany pine bush, where it was first discovered.
karner blue
given their typically short dispersal distance, the spatial arrangement of habitat is important to the conservation of the karner blue butterfly. distance between the various types of habitat required by karner blue butterflies is likely an influential landscape attribute. lane suggests that suitable karner blue butterfly habitat occurs in areas where open and closed canopies occur within a 590-foot (180 m) diameter. maxwell recommends considering the amount of shaded wild lupine habitat within the dispersal distance of karner blue butterfly when reducing overstory. many investigators stress the importance of habitat patches being closely spaced. for instance, at sites in west-central wisconsin, the average distance from an occupied wild lupine patch to another occupied patch was significantly (p=0.002) shorter (709 feet, 216 m) than to an unoccupied patch (1,155 feet, 352 m). wild lupine patches in the same area that were occupied by karner blue butterflies were also surrounded by a relatively low percentage of unoccupied patches. in addition, wild lupine patches in the allegan state game area that were occupied by karner blue butterflies were closer to other occupied patches than wild lupine patches without karner blue butterflies. this led to the recommendation that habitat patches be within 230 feet (70 m) of each other. isolation of habitat patches has been suggested as a reason for lack of karner blue butterfly presence on sites in new york. in addition, studies of karner blue butterfly dispersal have led to recommended distance between patches of ≤980 feet (300 m) to allow for dispersal and management units no wider than 1,300 to 1,600 feet (400–500 m) to improve recolonization of treated areas.
karner blue