The Great Blue Heron
A large blueish gray bird stands on a pile of damp rocks. Ignoring the humans floating towards it, the bird keeps its attention on the flowing river water streaming past the rocks. A flash of movement snags the bird’s attention. Keeping its eye on the unsuspecting fish, the heron arches it’s long, graceful neck back while smoothly extending one leg towards the fish. Once it’s prepared, the bird makes one swift shift in position that causes its body to straighten as it plunges its head beneath the water. It grabs the fish in it’s beak, shifting it so the head is pointed towards the bird’s gullet. Water streams off the animal’s beak as it lifts its head out of the water and swallows the entire fish.
The bird is the stately Great Blue Heron (Ardea herodias.)
Identifying the Great Blue Heron
Great Blue Herons are massive birds. The adults stand approximately four feet tall and have a wing span of six feet. It’s the biggest of all North America’s herons. The bird is named for the grayish-blue feathers that cover its body. The long feathers that line the outside of the wings are a much darker shade of blue. Light brown feathers draw attention to it’s long, slender neck which it carries in a tight S shape rather than extending it. Black and white accents on the head give the species a refined look. Adult Great Blue Herons are easily identified by the shaggy feathers that wrap around the bottom portion of its neck, feathers that aren’t seen on the juvenile birds.
While in flight, the heron keeps its neck bent.
Finding Great Blue Herons
You’ll locate Great Blue Herons throughout the North America, Central America, the Galápagos Islands, and even on some Caribbean islands. They can be found hunting in both fresh and sea water. They’re seen hunting in swamps, ponds, rivers, creek, and even shallow portions of the ocean. Males generally hunt near shorelines while females favor upland hunting grounds.
Feeding Habits of the Great Blue Heron
Basically, Great Blue Herons eat anything they can swallow. Fish make up a large portion of their diet, with the only real restriction being that the fish is only half the length of its bill. Once the Great Blue Heron catches its prey, it swallows the prey headfirst. In addition to fish, Great Blue Herons feast on amphibians, large bugs, small birds, and shellfish. Once in a while, you’ll catch a Great Blue Heron standing in the middle of a hayfield or pasture where it’s happily catching small rodents.
If something tasty doesn’t swim past the heron, the bird changes its approach. It moves into the water and drives fish and frogs out of hiding places so it can catch them.
Occasionally, a Great Blue Heron catches something that’s either too big for it to swallow whole or that has sharp spines that could tear at the lining of the bird’s throat. Rather than release the prey, the heron drops its head under the water and shakes the prey back and forth, sometimes banging it against a submerged tree or rock, breaking off the spines or bits of meat until the bird can safely swallow the meal.
Great Blue Heron Mating Habits
By nature, Great Blue Herons are an anti-social bird, but all that changes when it’s time to mate. When the need to procreate takes over, the herons gather in colonies that often include several hundred breeding pairs.
The males are the first to arrive at the rookery.
While there are always exception, Great Blue Heron rookeries are commonly found in heavily forested wetlands or on small, uninhabited islands that have lots of trees growing close together. Once the male has selected what he considers the ideal place to erect a nest, he gets down to the serious business of convincing a lade Great Blue Heron that he’s the greatest bird she’s ever laid eyes on. The courting rituals of the Great Blue Herons aren’t elegant. The displays involve lots of moaning/calling, feather preening, bill snapping, neck stretching, branch shaking, and displaying of crests. While it’s not uncommon for two males to bicker over the affections of a single female, the duels aren’t fatal. Because Great Blue Herons don’t mate for life, the males and females go through the courtship ritual every single breeding season.
Once two Great Blue Herons decide to couple off, they get down to the serious business of nest construction. It can take the pair anywhere from 5 to 14 days to complete work on their 3 feet by 3 feet nest. The male is responsible for gathering the construction material while the female creates the nest. The exterior is crafted from sticks. The pair likes to line the interior with moss and bits of green vegetation. The pair continues to tinker with the nest, adding and removing bits, the entire time they’re incubating the eggs.
With the nest complete, the female lays 2-6 bluish green eggs which are about 3 inches in long. It takes 27-29 days to incubate the eggs. The young Great Blue Herons can vocalize as soon as they hatch. They’re eyes are open, and their entire body is covered in a gray down. The parents share shifts during the incubation of the eggs and both remain involved in the lives of the hatchlings until the youngsters can fly and hunt on their own. The youngsters are strong enough for longish flights at about 60 days of age and usually continue to hang out with their parents for a few more weeks.
The Current Status of the Great Blue Heron
The Great Blue Heron population has been steadily increasing since 1966, but there are some areas, particularly in Florida where many waterways have elevated mercury levels, where the species has declined. It’s estimated that in North America there are at least 83,000 current breeding pairs.