Hobbies And Interests
Habitat
Great blue herons' main source of nutrition is fish, so they primarily nest near water, including rivers, lakes, marshes, swamps and seacoasts, where they can easily spot their prey, wade into the water and spear the fish with their long, sharp bills.
While they are usually solitary hunters, great blue herons prefer to nest in groups. Nesting in rookeries in tall trees cuts down on the chance that they'll be targeted by predators.
Life Expectancy
The oldest great blue heron ever found in the wild was 23 years old, but the average lifespan is around 15 years, according to the University of Michigan Museum of Zoology's Animal Diversity Web, while the Washington Department of Fish and Wildlife website states that most live only six to eight years.
Sixty-nine percent of all great blue herons die before reaching a year old, according to the Animal Diversity Web. This high mortality rate is due to predators consuming the young, as well as to the effects of cold weather and heavy rains on hatchlings.
Predators
Among the predators stalking great blue herons are bobcats, crows, ravens, eagles, raccoons, bears, turkey vultures, red-tailed hawks, gulls and coyotes.
Humans are also a threat, as we destroy the habitat of the great blue heron.
Other Causes of Death
Although predators pose the biggest threat to the great blue heron, a number are also killed each year when they collide with utility wires. They have also been known to choke to death trying to swallow fish that are too large.