Great Blues Are Going Great Guns

These ubiquitous herons are learning to live with people

Not one of our 50 states claims the great blue heron as its official bird — but most could. Regally plumed, strikingly colored and standing four feet high, it is among the most noticeable and ubiquitous of North American wading birds. Ranging over most of the continent, the great blue is a supreme opportunist, a survivor, and seems to have few problems coping with the 21st century. Indeed, its numbers, based on 30 years of random volunteer surveys, appear to be stable or increasing across most U.S. states and Canadian provinces.

Yet many wildlife experts think that if the highly adaptable great blue has an Achilles' heel, it is probably the shrinking number of places suitable for its nesting colonies. It is not uncommon for herons to pull out of a colony for no apparent reason. They seek out nesting areas that are isolated from intrusion by human and mammalian predators. Colony abandonment has also occurred when the great blue's only predator, the bald eagle (whose comeback is another success story), decides to nest nearby. In fact, the only region in North America where the species does not appear to be holding its own and is considered vulnerable is British Columbia. Researchers suspect that British Columbia's interplay of eagles, humans and herons is a likely harbinger for many areas.

Some evidence indicates, however, that the ever-adaptable great blues can adjust to human presence even during nesting. Author Tom Horton suggests that if we humans do our part to preserve wetlands for feeding and wooded spaces for nesting, the "marvelously adaptable great blue will meet us at least halfway."

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