10 Myths & Facts about Great Blue Herons

It’s a common sight to see the “lucky” great blue heron patiently hunting on the shores of Hood Canal and South Puget Sound. Largest of the heron species, up to 4’ in height, they actually only weigh between 5-6 pounds. Here are a few things you may not have known about these iconic Northwest birds.

  1. MYTH

Great blue herons only eat fish.

Great blue herons dine mostly on fish but they will also stalk everything from insects to small mammals and even other birds. In Washington, mice and voles making up a major portion of their winter diet when they choose to hunt on land.

2. FACT

Herons spend about 90 percent of waking time stalking prey.

Great blue herons grab prey in their strong beaks or use their dagger-like bills to impale. This action is known simply as a ‘bill stab’. They shake the prey to break spines before gulping them down. Great blue herons can swallow fish that are much wider than their narrow neck and have even been know to catch small birds in flight. Patience and speed are the keys to their hunting success.

3. MYTH

Great Blue Herons are cranes.

A crane is totally different type of bird. You can tell them apart by looking at the beaks and the way they fly. Cranes have shorter beaks and hold their necks straight when in flight, whereas herons curve necks into an S-shape. Herons are able to do this because of specially shaped vertebra. Great blues also fly with their legs ‘hanging” which is unique from most birds.

4.  FACT

Herons are often called “Dinosaur Birds.”

Fossil records date them back 1.8 million years ago, but they are thought to have existed about 25 million years ago during the Cenozoic age. Maybe it’s also because of the prehistoric sounds they make as they take off with the giant 6’ wingspan flapping!

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5. MYTH

Great Blue Herons can’t swim.

The great blue does many things that other herons choose not to do, including swimming in deep water with apparent grace and comfort.  A quick search on the internet will show multiple accredited images of herons happily swimming in deep water. It’s not a common occurrence though, so consider yourself lucky if you catch sight of this phenomena. Swimming is a testament to the great blue heron’s incredible adaptability.

6. FACT

Great blue herons have adapted “bib” feathers to keep them clean.

Specialized feathers on their chest grow continuously and fray into a fine cleaning powder. This powder is used to help groom their entire body and clean off fish slime.



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7. MYTH

Great Blue Herons are monogamous.❤️

Not technically. Great blues are known to be ‘serial monogamous’ — they have one partner for a year but choose a different one each mating season. Despite being territorial with other herons, they typically breed in nesting colonies at the tops of trees containing up to 500 breeding pairs. These colonies are called “heronries.” They obviously do not have any social distancing issues. Great blue herons generally return to the same breeding grounds each year although with different partner choices.

8. FACT

Mates work to build the nest, as well as incubate and feed their young –together.

When the mating pair is chosen, the male gathers sticks while the female weaves them into a platform nest lined with moss, grass, and small branches. She lays 2-6 blue eggs, and both parents take turns incubating them for 4 weeks until the young hatch. They also take turns feeding regurgitated prey to the young chicks.

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9. Myth

Heron chicks have yellow eyes when they are born.

Heron chicks have gray eyes when born that become bright yellow when they are adults. The parents continue feeding the nestlings for a few weeks after fledging (leaving) the nest. Young herons will fledge at around two months.

10. FACT

Great blue herons’ colors can demonstrate age, sex, and mating season.

Adult males are larger and generally have brighter orange legs than a female. During breeding season, the lore (the lore is the region between the eye and bill) will turn a bright blue, the iris will turn reddish, and the yellow bill will take on an orange hue.

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A couple other things you didn’t need to know about great blue herons:

  • To keep cool they flutter their throat muscles to increase evaporation.

  • It can take up to two weeks to build a nest.

  • Life expectancy of a great blue heron is 15-23 years

  • Despite their size they can fly as fast as 30 MPH.

  • An adult heron consumes up to one pound of fish per day.


Learn more


The Cornell Lab - all about birds

Audubon - Great Blue Heron guide

Olympic Bird Trail - Top birding locations on Hood Canal, South Puget Sound, Pacific Coast, and Olympic Peninsula

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