Spring Migration Arrival: Green Heron

Each spring, Green Herons migrate to Northern Illinois, arriving around April to breed and nest. These shy birds, often seen around Carillon Stonegate Pond, particularly along the western pond's banks, are known for their short, stocky build with deep greenish-blue backs and rich chestnut breasts and necks. Despite their common presence, Green Herons are rarely observed due to their elusive nature. They can be found patiently waiting for fish near the shore or on fallen tree trunks. At the end of summer, they migrate south to winter in Florida, Mexico, and Central America.

Identification: The Green Heron, despite its name, differs greatly from the Great Blue Heron. It is short, stocky, with a barely visible neck and short legs. In low light, they appear dark, but in better light, they show a deep greenish-blue back and rich chestnut breast and neck. Their neck, kept drawn up against their body, is hardly noticeable. They have broad, round wings, a long, dagger-like bill, and yellowish short legs. The Green Heron measures about seventeen inches in length, with a wingspan of over twenty-six inches, and weighs around eight to nine ounces.

Habitat at Carillon Stonegate Pond: While Green Herons are quite common, they are said to be shy birds such that they are rarely observed. So, with that caveat, look around the banks of Carillon Stonegate Pond – especially the western pond with some trees on the northern bank. You may find a Green Heron sitting on the bank or on one of the fallen tree trunks patiently waiting for fish to arrive near shore. Seasonally, they will be around in late spring through the summer.

Flight Patterns: Green Herons are distinctive in flight with slow, steady beats of their rounded wings. And, in flight, they may briefly unfold their neck, giving a very recognizable image. They also perform display flights to announce or mark their territory.

Behavior: Green Herons stand motionless at the edge of Carillon Stonegate Pond as they hunt for fish and amphibians. Sometimes they actually “fish” and use "bait." They will drop fish food pellets, bits of bread (from people feeding birds and ducks at a park), or flower petals into the water to lure fish within striking distance. Green Herons also have a characteristic slow, deliberate walk. But it is their ability to stretch that short, "no neck" neck that is startling. In fact, that is when they are most likely to "stretch" it. When the Green Heron is startled, it will stretch its neck up as far as it will go (see photos).

Diet: Mostly fish. Green Herons eat mainly small fish such as minnows, sunfish, and catfish. They will also dine on crayfish and other crustaceans, aquatic insects, frogs, and tadpoles.

Residence: Green Herons reside across the eastern U.S. during the summer into early fall. Their habitat includes wooded ponds, marshes, rivers, and estuaries. Green Herons are common breeders in coastal and inland wetlands. They winter primarily in Mexico and Central America.

Breeding and Nesting: Green Herons will breed during late spring across the eastern U.S. According to Illinois Department of Natural Resources, the Green herons begin arriving in Illinois in April and nesting occurs from May through early July. They nest in trees, usually near water. They may lay up to five eggs that will incubate for approximately three weeks. The young usually climb about near the nest around two weeks after hatching. They will make their first flight over the following week. They generally have one brood per year.

Migration: In Illinois, Green Herons are common migrants. They migrate north in the spring across most of the eastern U.S. to breed, including Illinois. They will migrate south around August and spend winters in Florida, Mexico, and Central America.

Conservation Status: Green Herons are classified as a Low Concern. Green Herons are still common, although their population shows steady decline of 1.8% annually, according to the North American Breeding Bird Survey.

Vocalizations: Green Herons give a harsh “skeow” call that is a distinctive sound of the wetlands where they reside. Here is a link to the sounds of the Green Heron.

Interesting Facts:

• Green Herons sometimes lure in fish using small items such as twigs or insects as bait.

• Unlike the fishermen that we see at Carillon Stonegate Pond who change locations every five minutes, the Green Heron is patient, standing still in one place and waiting for prey to approach them.

• They nest as isolated pairs or in small groups, rarely in large colonies as the Great Blue Heron does.

• Green herons have especially acute vision and hearing.

• The oldest recorded Green Heron was approximately 8 years old.

For more information on the Green Heron and sources of information used in this blog (these are the sources that I am using to learn as I blog), please visit All About Birds, Audubon Society, Nature Mapping Foundation and University of Michigan Animal Diversity Web.  And the Cornell Lab of Ornithology provides a wonderful source of information for anyone interested in learning more about birds.

​We all benefit from the variety of wetland, forest, and prairie environments that support diverse wildlife, plants, and insects of Carillon Stonegate Pond.

Take a hike and see what you can find – and identify!