WHICH NICHE
by Jillian Glover
One of my favorite cold season pastimes is to watch the activity at the bird feeders. Most of our feeders are on the north side of the house, which is built into an embankment. We look out in to the canopy of a dense scrub oak- pitch pine forest. The south side of the house is at ground level. These feeders are at the edge of an open field spotted with occasional oak trees. They are less visited, suited best for ground feeding birds, but also offer an option for birds driven away by the action on the opposing side of the house. At our feeders, suet, seeds, mealworms, and random berries are available.
The visual characteristics of the woodpecker family, Picidae, include a long chisel like bill, stiff tail, undulating flight, and zygodactyl feet. The stiff inner tail feathers allow the individuals to prop against a vertical tree while probing for insects. A zygodactyl foot refers to the atypical configuration of two toes pointing forward and two toes pointing backwards. This allows the bird to securely grasp bark with dexterity. The majority of bird families have two toes pointing forward and two toes pointing back.
Two less visible characteristics include a long protrusible tongue, and a skull adapted to protect the brain while drilling and drumming. The most distinctive of these is what is referred to as the hyoid apparatus. It refers to the tongue. The woodpecker can extend the tongue around the back of the brain. This feature assists in probing deep below the bark for insect and the like. It can be so far elongated, that in some species it almost reaches the nostrils. In addition, the end of the tongue is equipped with barbs to assist snagging prey deep in the bark.
The protection of the woodpecker’s brain from excessive drilling has been studied. The theory is that there is a relatively spongy bone in front of the skull protecting the softer brain tissue. More recent research is focusing on the existence of stronger neck muscles and cranial bone structures compared to other bird families. Either physiological feature could be the protective adaptation. Continuing to ask questions, observe and research help us all learn and move forward.
Back to the four species foraging in the backyard.
Downy and hairy woodpeckers are visually similar from a distance. They both have white backs and underparts. The wings are patterned with black and white. The head has a black stripe and cap. Male birds have a red back cap. The downy woodpecker is the smallest of the four woodpeckers that visit our feeders, and is actually the smallest woodpecker in North America. The downy will travel along in mixed flocks of small wintering birds that find food and protection as a group. The rest of the year it is most often found in woodlands bordering open areas. Weighing less than other woodpeckers, this species has the ability to forage further out on small branches and will also take advantage of seeds on forbs and grasses. The bill is relatively short and stout for a woodpecker.
The hairy woodpecker is a medium sized woodpecker. It is slightly larger and bulkier than the downy. It prefers the denser deciduous and coniferous woods. The bill is longer allowing it to drill deeper into rough bark, as well as peel pieces off of larger trees in search of prey. The feet of the hairy are comparatively stronger, allowing it to grasp and forage on the underside of branches. It is more of a solitary bird, not seen as much during the breeding season.
The red-bellied woodpecker is a medium size woodpecker. It has the advantage of being an omnivore, having a more varied diet. Their habitat is broad, living in open deciduous or coniferous forests and swampy areas. It prefers trees with softer bark for foraging. Although called the red-bellied, it has just a slight red wash. The striking red nape along with the black and white barring on both the back and wings make this species distinguishable. In addition, the male has a red crown.
The northern flicker is the largest of the four woodpeckers. This species can extend its tongue two inches beyond the tip of the slightly down curved beak. Although the northern flicker is common at the feeders this time of year, its normal diet is mostly insects. The extremely long tongue with barbs allows it to extrude ants from underground tunnels and is often seen on the ground foraging in open areas or at the edge of woodlands. The plumage of this bird is very distinct. Both sexes have brown backs with black bars, the underparts are black speckled with a black bib. Males have a red crescent on the nape and a black mustache. Most eye catching is in flight, showing a white rump and bright yellow under wings.
For the most part these four species of woodpeckers are considered beneficial to human endeavors. The larvae, caterpillars and insects that often cause damage to orchards, woodlots and urban plantings are a large portion of their diet. However, the springtime territorial drilling on buildings is not in their favor. The louder the object resonates, the more satisfied the bird is for announcing its territory. To the contrary, homeowners are frustrated and unhappy. In most situations it is a temporary behavior. A few solutions that work include hanging windsocks, tin foil strips or pinwheels for deterrents at the chosen sights. Probably not what you would choose to temporarily decorate your house with in the spring, but maybe worth the effort.
Soon these species will disperse to their most preferred habitats as well as prey. Regardless of the variety of each species niche, all of these woodpeckers nest in cavities. The availability of dead and decaying trees is a crucial part of their existence. I hope you, too, have been able to enjoy the variety of woodpeckers at your feeders during the cold season on Cape Cod.