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Northern Flicker - Unsung Hero of the Cavity-Nesting
World
By Lisa Bate
 See
a flash of red-orange from a flying bird, hear the
familiar “flicka, flicka, flicka” call and I know that
one of my favorite birds has just landed. It is the
Northern Flicker (Colaptes auratus)! This species
is unmistakable in the field because the lower surface
of its wings and tail are a bright salmon color. Yet it
is not just the color of the flicker that makes it one
of my favorite birds. Northern Flickers play such an
important ecological role for so many species, in so
many kinds of habitat, that I am always grateful when I
see this bird, knowing that without them, the wildlife
world would not be nearly as rich.
Northern Flickers range throughout North America and are
the second largest woodpecker in northwestern Montana.
Only the pterodactyl-like Pileated Woodpecker is larger.
Flickers are split into two subspecies: the eastern
yellow- and the western red-shafted flicker. Their
scientific name which refers to the yellow-shafted
flicker has two origins. Colaptes comes from the
Greek word “to peck” and auratus comes from the
Latin word meaning “golden.”
In northwest MT we have the red-shafted flicker (Colaptes
auratus cafer). In addition to the brightly colored
lower surface of the wings and tail, red-shafted
Northern Flickers have a brown barred back, gray head
with brown cap. A white rump patch is easy to see when
in flight. Males have a red moustache. They average 12.5
inches in length with a wingspan of 20 inches. Where the
yellow- and red-shafted flickers overlap, ornithologists
have been intrigued by hybrids of the two subspecies for
more than a century.
Northern Flickers forage primarily on the ground for
ants and other insects. In the winter flickers will also
forage on seeds, fruits and at local bird feeders. In
our area flickers will either migrate south, or to lower
elevations, for the winter. Research shows that flickers
rely more heavily on snags as foraging sites in the
winter when the ground is covered with snow.
I think of the flicker as the unsung hero of the
cavity-nesting world. Without Northern Flickers, many of
our other wildlife species would either disappear or be
present in much lower numbers. Ecologists refer to these
as “keystone species.” A keystone species is one that
makes up only a small number of the animals in an area,
but whose presence allows for the presence of many other
animals. The role of such an animal in an ecosystem is
like the keystone, or central stone, at the top of an
arch. While there might not be a lot of weight on the
keystone because of its position at the top, without it,
the arch would collapse. Without Northern Flickers, an
entire web of other species would collapse.
Many species are considered cavity nesters, but most
cannot excavate their own nest cavities and are thus
known as secondary cavity-nesters. Flying squirrels are
an example. They are the second ones to use a cavity
made by a woodpecker. Species that are capable of
excavating their own nest sites with their powerful
beaks are known as primary cavity nesters. The Northern
Flicker is a primary cavity nester and can excavate a
new nest site every year. The abandoned cavities are
then left for other species.
Flicker holes typically range from 2.5 to 3.5 inches in
diameter. This is exactly the right size of cavity that
many of our secondary cavity nesters need for their nest
sites, just large enough for the secondary cavity
nester’s body to pass through while limiting the chances
of a predator getting in. For example, almost all
American Kestrel nests are found in large (> 20 inches)
diameter snags with an abandoned nest cavity made only
by Northern Flickers. Kestrels do not use the abandoned
nests of woodpeckers such as the Hairy, Three-toed, or
Downy. These are too small. The abandoned Pileated
Woodpecker cavities are too large. I once watched as a
Cooper’s Hawk tried to prey on kestrel nestlings in an
old flicker hole. After an hour, it still had not
succeeded. It just could not get into the cavity.
When flickers nest near water, other bird species, like
the Bufflehead, benefit. Although they are a duck, they
are also a secondary cavity-nester and use old flicker
holes almost exclusively for their nests. Can you
imagine living in Montana without Mountain Bluebirds?
Neither can I. Again, we have the Northern Flicker to
thank for providing nest sites for the bluebirds. Both
Tree and Violet-green swallows also nest in old flicker
holes. Even some small owls take advantage of old
flicker holes. European Starlings also strongly prefer
flicker cavities (which, as you know, is not a good
thing). Then there are the flying squirrels, the red
squirrels, bushy-tailed wood rats, and small rodents
that depend on flicker holes. Without flickers to
excavate nest cavities, many of these species would
disappear from an area. Thus, Northern Flickers are
considered a keystone species.
Although Northern Flickers are still considered common
throughout North America, there is evidence of a
population decline noted since 1966, possibly due to
loss of suitable nesting and foraging snags, competition
with European Starlings, and pesticide applications on
lawns, golf courses, and agricultural fields.
I do realize that everyone may not be excited about
Northern Flickers. They can bring headaches if they
decide that your house should become their house, too.
The best way to keep flickers off your house is to
provide them with suitable trees or snags for nesting
nearby. Flickers are territorial, so if you have a pair
nesting in a tree or snag in your yard, they will keep
others off your house. Flickers will also forage on your
house if there are insects hiding in the siding or
roofing, so keeping the cracks and crevices to a minimum
will also help.
To encourage Northern Flickers (and kestrels, bluebirds
and swallows) to nest in your yard, allow some of your
older trees with decay to remain. Flickers are not
strong excavators and need softer wood to excavate their
nest cavities. If a tree or snag is unsafe, consider
topping it to 10 or 20 feet in height so they can have a
nest site and you don’t have to worry about high winds.
They like larger diameter trees and snags. While
gathering firewood, first examine the snag for signs of
wildlife use. If you see a cavity or recent foraging
signs, choose another snag for firewood. Other things
you can do to help Northern Flicker populations are to
discourage European Starlings from nesting in your yard.
Finally, choosing lawn products that are wildlife
friendly can help this ground feeder. Together, there
are many things we can do to keep Northern Flickers
strong in their role as the unsung hero of the cavity
nesting world. |
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