Cool things to know about P.E.I.'s great blue herons

They look almost as if they've been planted at the water's edge so you can take their photo and post it as an ad for P.E.I. tourism.

Great blue herons are the largest and heaviest of the herons that are native to North America.

Although they are a common sight in spring and summer, here are some cool facts you may not know about these birds.

CBC talked with Dan McAskill, editor of Island Naturalist, Nature P.E.I. board member and a passionate bird watcher for 60 years, and with Dwaine Oakley, an instructor with Holland College's wildlife conservation technology program andbird enthusiast with a wealth of knowledge about Island wildlife.

1. They are not cranes

Many people on the Island commonly call great blue herons "cranes."

"Herons and cranes are not the same thing and are actually quite different," Oakley said. "Cranes are more of an agricultural field browser preferring to eat grains etc., while herons are typically more water-based when seeking food." Herons' diet is mostly fish and amphibians.

Also, great blues fly with their necks in an "s" shape while cranes fly with their necks fully extended, he points out.

2. They nest in trees

Great blue herons nest in breeding colonies called rookeries. On P.E.I., they prefer spruce trees and nest in the trees' canopy tops and mid-canopy level.

"My favourite place to view breeding great blue herons on P.E.I. is Ram or Glenfinnan Island which is located on the Hillsborough River at the bottom of Battery Road in Tenmile House," said Oakley. "It is always interesting to watch these large wading birds perched precariously atop the large white spruce trees on the island."

The herons also take to the trees during high tide.

They make their nest from sticks gathered from the ground and lined with needles, leaves, rushes, small twigs and other material. They will steal branches from nearby nests if they have a chance.

3. Do not disturb

It is important that their colonies are not disturbed during the nesting season, McAskill said, as young can fall off the nest and die.

Herons lay between two and six eggs a year, and incubate them for just under a month.

4. People used to hunt them

Great blue heron were once hunted for their plumes until legislation was imposed to stop this practice, McAskill said.

In 2004, 530 pairs of great blue herons nested on Glenfinnan Island and, while many nest trees have fallen 165 nests were still present in 2018, McAskill said.

5. They're lightweights

Despite their large size 1.2 metre long with a 1.8 metre wingspan they only weigh about 2.4 kilograms.

"This is in part due to the hollow bone structure of birds," explains McAskill.

6. They're snowbirds

Most great blue heron that visit P.E.I. are migratory but a small number of them occasionally overwinter on the Island where there is sufficient open water, said McAskill. Most migrate in fall to warmer areas.

7. The eyes have it

Great blue heron can hunt at night thanks to a high ratio of rod-type photoreceptors in their eyes which enhance night vision.

8. They're, um, messy

For anyone who has ever conducted a census of a great blue heron colony, really good rain apparel is essential, said McAskill.

"When they jettison their waste, they can cover you and it is quite a memorable smell!"

It may be advisable for most birdwatchers to keep a bit of a distance, if possible.

"It's an impressive quantity of excrement which can whitewash you. Remember, they're releasing it from the tree top or mid-canopy level so it has some momentum to go along with its liquid nature."

9. Not picky eaters

While fish are herons' favourite food, they also stalk and eat amphibians including frogs, toads and salamanders, small mammals, snakes, insects and sometimes small birds.

Herons will often impale larger fish with their sharp beak and shake it before swallowing it.

They regurgitate their food to feed their young.

If people happen to come across an injured heron they should take every precaution to avoid their dagger-like bills which they use to defends themselves from predators, said Oakley, adding "it is best to call wildlife officials who are trained to take care of such situations."

10. Long live the herons

The oldest great blue heron on record was at least 24-and-a-half years old, McAskill said.

More P.E.I. news