Pennsylvania Game News - March 2019 - 47

the winter. Others pass through; evening
grosbeaks have been recorded as far south
as North Carolina in 2018-19. Food is
what holds them. They'll keep moving
until they find it.

FROM THE WEST
Evening grosbeaks were a western
boreal forest species until something -
proliferation of box elders, spruce budworm outbreaks - caused them to expand
their range east.
They were considered rare in the eastern United States until the mid-1800s.
Nineteenth-century ornithologist B. H.
Warren reported them in western Pennsylvania in December 1889 in scattered
flocks from six to 20 birds. In subsequent
years, the birds would appear in eastern
counties, too.
George Miksch Sutton, in his 1928
Birds of Pennsylvania wrote of evening
grosbeaks that in winter they congregated
wherever they found food, especially
berries, maple and ash seeds, even frozen
apples
"Evening grosbeaks see so little of
man in their wilderness home in the
Great Northwest that they are surprisingly
unsuspicious when they visit us during
winter," Sutton wrote.
Once a relatively regular visitor to
Pennsylvania, particularly in northern
counties, evening grosbeak visits and
irruptions into the state became rarer in the
1990s. Their winter sightings have been
limited since the start of the 21st century.

GONE
Their disappearance from Pennsylvania winters appears related to a sharp
population decline - 97 percent in the
eastern part of their range, according to the
North American Breeding Bird Survey.
The evening grosbeak's rise and
MARCH 2019

decline over time in Pennsylvania can be
measured through Audubon Christmas
Bird Count data. The birds were being
recorded by censusing birders early in
the 20th century. But grosbeak irruptions
really got their start in the 1950s and built
through the '60s.
Through the '80s, they were almost
annual winter visitors. But after that,
grosbeak irruptions dried up.
Only minor irruptions in 1999 and
2011 have occurred in the past 20 years.
Early in winter, it was too soon to determine the size of this season's irruption.
"The last year I saw an evening grosbeak in Pennsylvania was 1998, when a
nice flock appeared at my feeder," Brauning recalled. "It was 1991 before that.
"It's obvious something has gone
very wrong for evening grosbeaks in the
eastern part of their range," Brauning
said. "Their ongoing irruption represents
a fraction of what Pennsylvania had experienced 30 to 40 years ago."
Three years ago, the evening grosbeak
became one of the 432 species on the
State of North America's Birds' Watch
List. It was considered a "species most
at risk of extinction without significant
conservation actions to reverse declines
and reduce threats."
And in August, the Committee on the
Status of Endangered Wildlife in Canada
in August 2018 listed the evening grosbeak a species of "special concern" in
response to strong population declines
occurring mainly in central and eastern
Canada.
The plight of evening grosbeaks dovetails with that of about 30 percent of the
continent's birds, according to the 2016
State of North American Birds Report,
which is developed through collaboration
among the U.S. Fish and Wildlife Service,
American Bird Conservation Initiative
47
Pennsylvania Game News - March 2019

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