Genetic analysis at the state museum confirms what biologists squishing through Adirondack bogs already knew: New York's population of the spruce grouse, a chicken-like bird of the boreal forest, is nearing extinction.
Avid birders travel great distances to glimpse rare boreal species in the cool, moist forests of the Adirondacks and other Northeastern mountains. While boreal species - including the boreal chickadee, Bicknell's thrush, blackpoll warbler and gray jay - are plentiful further north in Canada, biologists say global climate change and habitat loss are driving them out of the southern reaches of their range.
The spruce grouse is the most threatened of all because it lives in isolated and shrinking patches of bog and doesn't fly off in search of new territory like songbirds do. Biologists estimate there are 100 to 200 left in the Adirondacks.
The state Department of Environmental Conservation has drafted a Spruce Grouse Recovery Plan, to be released this summer, which will explore ways to save the species. Among the possibilities is capturing spruce grouse in Ontario, where they're plentiful, and releasing them in the Adirondacks to refresh a gene pool depleted by decades of inbreeding.
Jeremy Kirchman, curator of birds at the New York State Museum, has studied DNA from blood samples of spruce grouse captured by researchers in the Adirondacks and compared it with samples from 100-to-150-year-old Adirondack spruce grouse specimens in museum collections. He also compared it with modern birds from other areas.
"Among 22 modern birds in the Adirondacks, 19 were genetically identical" at the gene selected for comparison, Kirchman said in a recent interview. "In six birds from Ontario, almost every individual was unique." The same was true for samples from spruce grouse in Minnesota, Michigan and Washington state, and for the old museum specimens.
"That's what you'd expect in a big, healthy population," Kirchman said. "The spruce grouse across its range is highly genetically diverse at this gene. But this little island population in the Adirondacks is not."
In 2008, Vermont's Fish and Wildlife agency started augmenting that state's spruce grouse population, estimated at about 100, by trapping and relocating 134 birds from Maine and Quebec to the Victory Basin Wildlife Management Area in northeastern Vermont, according to John Buck, an agency biologist. It'll take 10 to 15 years for the success of that project to be realized, he said.
If New York attempts a similar effort, it will use Kirchman's DNA studies to select birds similar to the genetic makeup of the Adirondack population.
The spruce grouse population in New York is confined to 15 sites, down from 23 sites in 1987, according to DEC.
"In the past, declines were probably linked to loss and fragmentation of habitat due to intensive, large-scale softwood logging occurring around the late 1800s," said Angelena Ross, a DEC biologist who has studied spruce grouse for many years along with Glenn Johnson, a biologist from the State University of New York at Potsdam.
"Our studies suggest that the spruce grouse may be declining now because of changes in forest structure and composition related to the maturation of coniferous forests," Ross said.
The ruffed grouse, while not endangered, is also declining in the maturing hardwood forests of the Northeast because they need the cover provided by young trees, Ross said.
DEC's restoration plan may include habitat restoration by removing old trees to let young ones spring up. That would likely help boreal songbirds as well as spruce grouse, Ross said. But that could only be done on private forest tracts because tree-cutting is prohibited on state land in the Adirondacks.
Spruce grouse use feather sounds during courtship and perform a complex mating dance where they swish their tails from side to side while walking and end the display with a simultaneous flick of the head and fan of the tail.
"They are a groovy bird," Ross said. "In my opinion, they are a symbol of the boreal. They are interesting because they literally eat the boreal forest - eat tamarack, spruce and fir needles."
While the genetic diversity of New York's spruce grouse is not what it was a century ago, the ill effects of inbreeding - such as fewer chicks, higher mortality rates and increased disease - are not being seen, Ross said.
"So before we go mucking around adding birds into the state, we have to know that it's necessary," Ross said. "Without any real indication that our birds' reduced genetic diversity is a negative, it's a tough sell. However, there are other reasons defined in our recovery plan that may indicate that it may be helpful."
The plan will be released for public comment soon, she said.
Explore further: Mown grass smell sends SOS for help in resisting insect attacks, researchers say