Often enough we hear about conservation stories heading in the opposite direction--but in eastern New York, an endangered blue butterfly, the Karner blue, is on track to recovery after 20 years of habitat restoration and breeding programs, as a preserve there has noted.

That's fitting, as the butterfly was first discovered in the pine barrens of upstate New York by Russian author Vladimir Nabokov, decades ago.

These pollinators are silvery blue and about the size of a postage stamp. First put on the federal endangered list in 1973, they are experiencing a comeback in Ohio and New Hampshire, and they continue to live in Wisconsin and Michigan.

Blue populations in some other parts of their former range between Minnesota and New England are not doing as well. According to the U.S. Fish and Wildlife Service, reasons include habitat loss from land development and suppression of wildfires that would otherwise renew the pine barren and black oak savanna where the insects live.

In New York state in the area around the 3,200-acre Albany Pine Bush Preserve, butterflies have been released at 21 sites and they naturally colonized other locations in the preserve. Since 1991, the Karner blues have increased from about 200 to more than 14,000 now, as Neil Gifford, conservation director at Pine Bush, said, according to the AP.

In order to be considered a recovering population by federal statutes, the winged insects should have a population over 3,000 in four of five consecutive years. Gifford thinks the recovery goal will be met next year, he said in the AP article.

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