Sunday, January 27, 2008

Common Feeder Birds: Downy Woodpecker

Downy Woodpecker Female

My sister-in-law described a bird to me that she thought was a woodpecker. She told me it was black and white and striped like a skunk. At first, I was confused, but then realized she was describing one of our most common woodpeckers, the Downy Woodpecker (Picoides pubescens).

Downy Woodpeckers live throughout the United States and are found year-round as far north-west as Alaska and as far south-east as the tip of Florida. That is a huge climate range!

They are a little over six inches in length with a white chest, black and white dotted wings and a white patch on their back. This patch is what reminded my sister-in-law of a skunk. They have a black head with a white stripe above the eye and another white stripe near the bill. They have a black tail with white outer feathers and small dark bars on the edges. They have a small, pointed bill. The male has a small red patch on the back of the head that the females lack. The juveniles will sometimes have a small red patch on their forehead.

Downy Woodpecker Male

Downy Woodpecker Juvenile

Their second part of their scientific name, "pubescens", refers to the white tuft of nasal bristles near the bill. These modified feathers help protect the nasal cavity from debris that is formed by chiseling and hammering on the bark of trees.

Downy Woodpeckers are fascinating to watch as they propel themselves up the side of a tree, using their tail as a spring, hopping along, stopping from time to time to investigate a nook or cranny that may hide a juicy insect. Their bill is less chisel-shaped than that of other woodpeckers, and they use it like a pick for dissecting insect tunnels just under the bark. The bill is also used like a pair of tweezers to pick tiny insect eggs from the surface of leaves and bark. Their small size allow Downy Woodpeckers to perch on plant stems like that of the goldenrod. One of their favorite foods are the larvae found inside of goldenrod galls. For fascinating information about the insect behind these galls, go here.

Goldenrod Gall

Goldenrod Gall Larvae

One day we were watching our bird feeders when a Cooper's Hawk appeared. We watched a female Downy Woodpecker freeze in position against the trunk of the tree. I was amazed at how this bird never moved a muscle, but remained completely still. When the hawk flew to another tree, the Downy quickly shifted positions to the other side of the trunk, to not be discovered and remained ever so still. Finally, the hawk gave up and the Downy went back to foraging. Chris, our manager, commented on how it was like playing hide and seek, but the consequences were much higher if the bird had been discovered.

Downy Woodpeckers love to eat suet, peanuts and black-oil sunflower seeds at the feeders. My next post will be about the Hairy Woodpecker that looks almost the same as the Downy Woodpecker and can cause confusion with its identification.


Sunday, January 13, 2008

Common Feeder Birds: Red-bellied Woodpecker

Male Red-bellied Woodpecker. Photo by John Howard.

Woodpeckers are fascinating creatures with many amazing adaptations to aid in their survival. One of my personal favorites is the Red-bellied Woodpecker(Melanerpes carolinus). Melanerpes means "black creeper" in Greek, describing its movement up the side of a tree.

The Red-bellied Woodpecker is about nine inches in length with a red band on the back of the neck extending to the top of the head. The female's red band reaches to the middle of the head, while the male's reaches to the bill. The Red-bellied back is barred black and white. It common name comes from a light patch of red on the belly which is not easily seen when the bird is on the side of a tree.

Female Red-Bellied Woodpecker

Red-bellied Woodpeckers have a highly varied diet. They will feed on insects, preferably ones found on the bark and limbs of trees. In the winter months they rely heavily on plant material, such as berries, seeds and nuts. Occasionally, they will feed on small mammals, lizards, and nestling birds.

Red-bellied Woodpeckers will cache or store nuts, berries and insects in pre-existing cracks and crevices in trees, posts and vine rootlets. They will lodge them 5-7 cm deep to hide them from other animals. It has not been reported that they will defend these food stores.

Woodpeckers, in general, have amazing adaptations that aide in their survival. Their toes are zygodactyl with two toes forward and two toes back, almost forming an "X". This configuration allows the bird to get a firm grip on the bark of the tree. They, also, have stiff tail feathers that they use somewhat like a kickstand on a bike. These feathers help steady them as they hop up the side of the tree. Their brain is cushioned by an air-filled spongy tissue that acts like bubble wrap and the skull fits tightly around the brain to reduce jarring while they hammer away.
The most incredible feature of the woodpecker is its tongue. The Red-bellied has enlarged mucous glands under its tongue that produce a sticky saliva. The tongue is pointed and barbed at the tip and extends 2.5-4 cm beyond the bill. These features make the Red-bellied more successful at extracting insects from crevices than any other woodpecker. There is an excellent article on woodpecker tongues with fantastic pictures at Hilton Pond's website.
Red-bellied Woodpeckers love suet, peanuts and will also eat bits of dried fruit and black-oil sunflower. When you have a chance, take a closer look at the Red-bellied Woodpecker and admire all its amazing traits!

Friday, January 4, 2008

Common Feeder Birds: Dark-eyed Junco

On New Year's Day, my sister asked me to identify a bird at her feeder. She described it as a small mostly black bird with white and a yellow bill. As I watched out the window to see the bird, up pops a Dark-eyed Junco (Junco hyemalis).

This bird is also known as a snow bird, because they generally show up here in Indianapolis in the winter. We usually spot the first juncos in November. Its species name, hyemalis, is very appropriate since it means winter or wintery.

Juncos are a little over six inches in length with an average weight of nineteen grams. This is less than the weight of four shiny quarters. Despite their size, they are voracious eaters and enjoy hopping around on the ground picking up seeds the other birds have knocked to the ground. They will eat from the feeders, but prefer to scratch around on the ground.

When walking through a shrubby or grassy area, the juncos will be everywhere. They will hang in small flocks nervously darting around flashing their white outer tail feathers as they fly. Their call is a sharp, somewhat buzzy tzeet, that they utter while flying into the brush for cover.

There are a few races or subspecies of juncos here in Indiana. The most common is the Slate-colored, which is dark gray to black overall for the males and a gray-brown for the females. Both sexes have a white belly and white outer tail feathers. The Oregon subspecies is an uncommon winter visitor with a dark hood and a brownish back, white belly and orangish-brown flanks.

Oregon subspecies of Dark-eyed Junco

I am unaware of any juncos breeding in Indiana, but there have been accounts of them breeding in extreme northeast Ohio. The main breeding range for the slate-colored junco that frequents Indiana feeders is Canada, northeast Minnesota, northern Wisconsin, the northern lower penninsula of Michigan, central Pennsylvania and the New England area.

Enjoy these fiesty little birds at your feeders this winter. They love black-oiled sunflower seeds. Since they prefer to feed on the ground, I will cast some on the ground specifically for them and some of the sparrows. They will take suet, thistle and other seeds.