Discover the herons of Northern Minnesota
There are three species of herons that live in Hubbard County.
Marshall Howe is a retired biologist with the U.S. Fish and Wildlife Service who specialized in bird population studies and has been a resident of Hubbard County since 2010.
Great blue heron
He said the great blue heron is the largest heron species in the U.S. and its broad breeding range includes Hubbard County.
According to the American Bird Conservancy (ABC) (abcbirds.org), it s the largest heron in North America. At almost five feet tall, with a wingspan that can extend more than six feet, it is blue-gray in color with a black-striped head.
Great blue herons lay their eggs in a nest made of sticks and both parents incubate them for about a month.
The young leave the nest two to three months after hatching but depend on their parents for food for another three weeks.
According to the ABC, “The great blue heron is the most easily observed member of the heron family, not only because of its size but because it forages along shorelines on all of our lakes and often perches on docks,” Howe said. “The Great Blue Herons are colonial, meaning that many individuals nest in close proximity to one another. Their colonies are usually in tall trees. Because of the guano (excrement) that builds up over the years in a colony, the trees eventually die and the birds are forced to relocate. Birds will travel many miles from their nesting colony to feed. Unlike in the colony, these birds are solitary when foraging and actively defend their feeding territory against others of their species. They feed mainly on fish and frogs but occasionally venture onto dry land and pick off unwary chipmunks. Many people confuse great blues with sandhill cranes (which are not closely related to herons). They are similar in general stature but cranes feed primarily in fields, not in the water. In flight cranes fly with their necks fully extended, whereas great blues and other herons curve their long neck back into a tight S shape with the head seeming to rest on the base of the neck. When they spot a prey item, they coil their neck back and strike with lightning speed. Great blues migrate to the warmer parts of the U.S. and Mexico for the winter, returning to Minnesota for April through October.”
Howe said while this species is also common in this area, they are much less conspicuous because they are our smallest heron. About the size of a crow, green herons do not nest in colonies.
“They are well camouflaged with their green and brown coloration, and when feeding they crouch low as they sneak along usually heavily vegetated shorelines,” he said. “Unlike the deep croaking call of the great blue, green herons when flushed will often emit a unique, loud, high-pitched shriek. They hide their bulky nests well in trees and their nests are typically located close to their preferred feeding sites and often fly in pairs.”
Black-crowned night heronsThe least common heron in this area are the black-crowned night herons.
“Because they feed nocturnally, they are rarely seen. In the day, they roost well hidden in low trees or shrubs,” Howe said. “They are also quite uncommon in our area. They are most easily found in extensive marshes, like those at Agassiz National Wildlife Refuge in Marshall County.
Howe said that while great egrets do not nest in this area, they are seen occasionally during migration, especially in the later summer.
“They nest in colonies, mainly in the far western and southern parts of Minnesota, but are prone to wandering considerable distances to feed after nesting is completed,” he said. “They are more apt to feed in swampy areas rather than on lakeshores. Because they are completely white, they stand out at a great distance.”