Burrowing Woodpecker
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Burrowing
Woodpecker, Picifodiens
hypogaeria L 30-36 cm, WS 50-55 cm, Family: Picidae
IUCN Conservation Status:
Vulnerable (VU)
Description:
Large,
solid bird with a hefty chisel-like bill and long tail. Upperparts brown and heavily
patterned with light barring, undersides lighter or paler with dark barring on
the belly and undertail. Bright yellow undertail patch. Head covered in small
spots and a black moustachial stripe. Males have yellow coloring below eye, and
yellow-orange iris. Females lack yellow in face and have icy blue eyes. Built
like a woodpecker, but with especially long legs and rarely seen off the
ground. In flight, wings and tail rounded.
Voice:
Calls
typically a series of sharp, nasal “weck” notes, lasting several seconds.
Similar to the calls of flickers, only harsher. Other calls include soft,
whispering babble and various chattering. Emits near constant chattering when
in groups. Rarely drums.
Range and Habitat:
Uncommon
bird, range extends across Novasola’s interior steppe. Occasionally seen in the
chaparral surrounding Fairweather Sound and on East Francis Island, and has
been documented rarely in the Twin River Basin. Prefers open grassland,
shrubland, meadows, and arid ecosystems, especially with patches of low grass
or bare ground. Reliant on ground squirrels, especially Kusasha ground squirrel,
thus their ranges overlap almost perfectly.
Discussion:
So
unlike other woodpeckers, the Burrowing Woodpecker is a fascinating and
incredibly unique endemic bird. Along with the ground woodpecker of Africa and
two species of South American flicker, the Burrowing Woodpecker is one of only
four largely terrestrial woodpeckers and is possibly the most well-adapted of
all woodpeckers for an entirely terrestrial lifestyle, seldom taking flight let
alone perching on vegetation. Rather, it uses its noticeably long legs to run
along the ground, exceptionally strange for a woodpecker, and will run to avoid
threats and to hunt prey.
The
Burrowing Woodpecker’s diet consists mostly of ground-dwelling invertebrates
like ants and ant larvae, termites, beetles, and scorpions. On rare occasions
they may prey on ground nests for eggs. When foraging, they will peck at then
penetrate an anthill or termite mound, or just the ground, with their robust
bill and extend an incredibly long, flexible, and sticky tongue to lap up the
insects inside. They will also forage by picking prey straight off the ground,
though this is less common. Another behavior unique to this woodpecker is the
use of sentries during feeding. Because Burrowing Woodpeckers mostly forage in
groups, one member of the flock will act as a designated sentry, usually
perched on a rock, shrub, or a prominent place and watch out for predators
while the others feed, much like behaviors seen in ground squirrels and
meerkats. Throughout the day different individuals will take turns with sentry
duty. Flocks will communicate through frequent chattering calls, but the sentry
will sound a loud alarm call if a threat is detected, which causes the group to
run or take flight. Many other species, especially ground squirrels, also heed
these alarm calls. Likewise, the woodpeckers understand the alarm calls of the
ground squirrels, which usually share foraging areas, and can respond to their
distinct alarms for aerial or terrestrial predators.
As
their common name suggests, Burrowing Woodpeckers nest underground in burrows. Not
only is this burrowing behavior unique among woodpeckers, they also often nest
in small colonies of a few mating pairs, also uncommon for woodpeckers. They
breed and nest in these burrows, but will also roost in them year-round. Though
they will excavate their own burrows when none are available, they usually use
old or unoccupied burrows dug by other species, mainly ground squirrels. There
are many species of ground squirrel and burrowing mammals native to Novasola’s
prairie, and Burrowing Woodpeckers have been documented nesting in burrows made
by all of them, but by far the most commonly used burrows are those made by the
Kusasha ground squirrel. The Kusasha ground squirrel is the most numerous
squirrel in the intermountain steppe, and they form large colonial burrow
sites, like prairie dog towns. The squirrels live in large colonies and each
pair will dig their own hole near the rest of the group, and they will also
often dig a second decoy hole. Thus, each squirrel burrow site can have
anywhere between 5 and 80 holes, only half of which are usually occupied. Burrowing
Woodpeckers exhibit a direct, positive relationship with Kusasha ground
squirrel abundance, and though woodpeckers will use abandoned burrows, most birds
nest within the decoy holes of active ground squirrel sites or towns and will
use their strong bills to improve, excavate, or clean the burrows only as
needed.
This
reliance on ground squirrels is thought to be a mutualistic relationship where
both species benefit from the association. Firstly, the woodpeckers get the
safety of a burrow without having to dig themselves. Both the birds and
squirrels benefit from having extra eyes to watch out for predators. The
woodpeckers have better vision than the squirrels, and are often the first to
notice a threat, but both species understand and respond to the other’s unique alarm
calls. Furthermore, both species will defend the colony from threats; the birds
can mob mammalian and avian predators more effectively than the squirrels, and
the squirrels can draw attention away from the woodpeckers. Most ground
squirrels hibernate, but the woodpeckers stay active and remain in the colony
year-round and thus protect the site from predators and rivals in the winter
months. The Burrowing Woodpecker’s nesting behaviors make it the converse of
most other woodpeckers, in that most woodpeckers excavate their own holes and
thus become keystone species in their environments for providing habitat and
foraging sites for so many other species but the Burrowing Woodpecker relies on
the sites made by the prairie keystone ground squirrels.
The
woodpecker’s dependance on burrowing mammals has its drawbacks, however. Most
notably, Burrowing Woodpeckers have seen a steep decline in population since colonization
of Novasola, mostly as a result of habitat loss and the decline of ground
squirrels. As ranchers and farmers have spread across the prairie, development
has had disastrous effects on ground squirrels, which are hunted for food and
sport, killed by traffic, adversely affected by introduced and bolstered
predators like dogs, cats, ravens, and raptors, and threatened with constant
habitat destruction and fragmentation. As a result, Burrowing Woodpeckers,
which were always somewhat uncommon, are now considered a vulnerable species.
Conservation efforts have included the digging of artificial burrows and the
better management of squirrel populations, and they have shown some success.
Nevertheless, the Francis Burrowing Woodpecker, which was a unique subspecies
endemic to the Francis archipelago, has already gone extinct.
The
Burrowing Woodpecker was originally described in 1874 by Spencer Fullerton
Baird. The genus name Picifodiens hypogaeria roughly translates to
“digging underground woodpecker”. It is thought to be a close relative, and a
sister taxa, to flickers in the genus Colaptes. Another common name for
the bird, often used by ranchers, especially in the 19th Century, is
“Gopher Bird”. The bird features in Yukandaluk and Gallquayan indigenous
mythology, often as spirits of the underworld, and their names include yanax’shoox
and cixtiqatiq.
Rare,
secretive, and cryptic, the Burrowing Woodpecker can be one of the hardest endemic
woodpeckers to observe in the wild. Despite this, Richard Reichwald encountered
numerous flocks during the first NRC expedition in 1902, and more still during
the years leading up to Native Birds. Reichwald was one of the earliest proponents
of sustainable management of squirrels and badgers as a way of protecting the
birds.
“Inhabiting
the territory’s arid plains, the [Burrowing] woodpecker can be found in greatest
numbers wherever marmots or gophers are present. Indeed, the Gopher Bird is so
at home among the varmints that it has adopted many of their traits. The bird
not only roosts in the rodents’ burrows, but also lives in colonies like them,
takes guard duty like them, and even sounds like them. What’s more, the birds
are likewise parasitized. The gopher birds share with the gophers the same
fleas, ticks, and other pests with writhe through their feathers in quantities
unmatched by any bird. Truly it is a vile experience for a sportsman to have a
woodpecker in hand, and he must take great care afterwards not to spread fleas
to himself, his clothing, or his companions.
…
It
is quite difficult to approach the Gopher Bird knowingly. The birds are most
visible when perched atop a mound or shrub, though this is when they are also
most wary. The lookout will hardly allow a man to come within 10 yards before sounding
the alarm and scattering the flock. The best times to get close are with
individual birds, separated from a flock. When alone, the bird will not flee
but instead couch still and rely on its camouflage, which allows one to
approach within mere inches of the bird before it absquatulates on foot or by
wing. Unfortunately, their camouflage is excellent, and easily fools the human
eye, thus most often in these circumstances a sportsman might come very close
indeed to the bird and never know it; until the bird flushes it is near
impossible to find.
…
For
all to be said about their cryptic plumages and secretive nature, this should
not be confused for timidity. Indeed, the Burrowing Woodpecker is a resolute
and tenacious creature, at times seemingly eager to fight. They defend their
nests boldly against all manner of threats, often with the entire flock joining
in to pester would be intruders like foxes or hawks. I have observed birds
combating and even killing rattlesnakes near the burrow, and many badgers give
up their squirrel hunts when they accidentally approach to close to the
woodpecker burrow.” – Native Birds of Novasola, 1912