Woodpeckers may find their hidden prey by sound and/or smell.
As the woodpecker strikes the tree, hollow sounds may echo off of the tunnels (galleries) of wood boring insects (like thumping a watermelon.)
When feeding on wood, grubs make an audible sound that could be heard by a woodpecker.
Woodpeckers have a better sense of smell than most birds and may be able to detect the strong odour of the formic acid that ants, bark beetles and termites excrete (smells like Sweet Tarts.)
During cold winter weather, tree-foraging birds such as woodpeckers do not increase their body fat as much as ground-foraging birds, probably due to the fact that they roost in cavities overnight and that snowfall rarely hampers their ability to find food in trees as compared with birds searching for it on the ground.
Most species of woodpeckers are born completely naked, unlike many other birds that are completely covered with soft down feathers when they hatch.
To help distinguish the difference between a Hairy and a Downy Woodpecker visiting your feeders, look for the Hairy’s chisel-like bill which is much longer than the Downy, which often equals the width of the rest of the head. The Downy’s head is twice as wide as its very short bill.
Beetle larvae and ants make up the largest portions of the Hairy Woodpecker’s natural diet.
While not a true sapsucker, the Hairy Woodpecker seems to enjoy a sweet drink on occasion as they have been reported to drink from sapsucker wells, hummingbird feeders and even sugar cane plants.
The smallest North American woodpecker is the Downy Woodpecker at 6" in length.
The Downy Woodpecker was first formally described by the Swedish biologist, Carolus Linnaeus in 1766.
In winter, small birds tend to lose heat faster than larger birds due to the ratio of surface area to weight. As a result, Downy Woodpeckers in northern Canada are about 12 percent larger than they are in Florida.
The feather pattern on the back of the head of Downy Woodpeckers is unique to every bird and downies may use them to recognize other individual downies.
Scientific tests have determined that Downy Woodpeckers do actually use the presence or absence of the red patch on the back of other downies head to determine whether they are male or female.
Male Downy Woodpeckers are dominant over female downies and select the best feeding sites for their own use and defend them against the females.
Female Downy Woodpeckers have slightly longer tails than do the males. This may be explained by the fact that they spend more time foraging on vertical surfaces, such as tree trunks, and thus use their tail as a brace more often than their male counterparts, which spend most of their time foraging on smaller horizontal branches.