Great Blue Heron FAQ and Fun Facts

Frequently asked questions

Are Great Blue Herons endangered? No. The species is IUCN Least Concern with an increasing population (~700,000 breeders), though the Pacific fannini subspecies is of Special Concern in Canada, Florida's "great white heron" is Endangered on BirdLife's list, and Maine reports steep local declines.¹²

Do Great Blue Herons mate for life? No — they are seasonally monogamous, choosing a new mate most years, though pairs that reunite at a colony may re-bond quickly.³⁴

How big are they, really? Up to 4.5 ft tall, 97–137 cm long, 167–201 cm wingspan — yet only about 5–6 lb, thanks to hollow bones.⁵⁶

Is it a crane? No. Cranes fly with necks outstretched, eat mostly plants, and can't perch in trees; herons fly with necks folded, eat animals, and nest in trees.⁷

Can they hunt at night? Yes — rod-rich eyes give them excellent night vision; they are among the only members of their genus that forage after dark.⁸

What do they eat besides fish? Frogs, snakes (up to ~3.5 ft water snakes), turtles, crayfish, crabs, insects, voles, gophers, mice, muskrats, even rabbits and other birds.⁹

How long do they live? About 15 years on average; the banding record is 23–25 years. But ~2 of 3 die in their first year.¹⁰¹¹

Why did one squawk at me? You surprised it. The harsh "frawnk" is an alarm call that can run 20 seconds.¹²

Are they dangerous to people? No — but never handle one: the lightning-fast bill strike can cause serious injury, and handlers have been struck at the eyes. Call a wildlife rehabilitator for injured birds.⁶

Do they migrate? Some do, some don't. Northern and eastern birds head south as water freezes (some to Central America); Pacific coast, Florida, and Galápagos birds stay year-round.¹³

Where do they sleep? Communally, usually 5–20 birds in tall trees near water.¹⁴

Is the white one in Florida a different bird? It's the "great white heron" — officially a subspecies of the Great Blue, but with genetic and behavioral evidence for full species status; look for pale legs to rule out Great Egret.¹⁵

Twenty fun facts

1. The scientific name means "heron heron" — Latin ardea + Greek erōdios.¹⁶
2. One GPS-tracked heron, "Harper," flew 1,424 miles nonstop over the ocean in 38.6 hours.¹⁷
3. Herons groom with powder down — self-generating feather dust that soaks up fish slime.⁸
4. The comb on their middle toe is called a pectinate claw.¹⁸
5. In Nova Scotia, 98% of one population's diet was flounder.⁹
6. In Idaho, 24–40% of the diet was voles — these "water birds" are serious mousers.⁹
7. They can swallow fish up to 60 cm (2 ft) long — and occasionally choke trying.⁹⁶
8. Chicks gain 40× their hatch weight in 8 weeks.³
9. Eggs are pale blue and fade as incubation progresses.⁵
10. Nests grow from 20-inch platforms to 4-foot-wide, 3.5-foot-deep fortresses over years.⁵
11. Colonies can exceed 500 nests, yet the same birds hunt alone all winter.⁵
12. A family of four burns about 2,000 calories a day.³
13. Seattle made the Great Blue Heron its official city bird in 2003.¹⁹
14. Vancouver's Stanley Park colony has been nesting there since 1921.³
15. Herons sometimes nest on channel markers, duck blinds, and beaver mounds.⁵
16. Parents incubate through snowstorms and have fended off Great Horned Owls on camera.²⁰
17. The first-hatched chick may bully younger siblings to death — siblicide is normal.²¹
18. At hatcheries, herons were found to eat mostly diseased fish — unintentional quality control.⁸
19. They occasionally turn up in Europe — one made the British List in 2008.²²
20. The genus Ardea is at least 15 million years old.²³