Saturday, October 07, 2006

Great Blue Herons

These large predators are frequent visitors here, but the fishermen and others along the river keep them from becoming resident long term. Their harsh guttural squawks can be heard at any time of the night or day. Always solitary in daily life, they surprise everyone by nesting in large clusters of huge nests, from 8 to 170 in a single tree or group of adjacent trees near water.

Last spring we observed a pair flying together or following one another several times, which is unusual.

These herons are 'great' due to their size - a wingspan up to 6 feet (1.8 meters) and a height of 42 inches (1.4 meters). Three-quarters of their diet is fish, and are indeed usually seen fishing in rivers and lakes. Great Blue Herons also grab crawdads, insects and frogs. They will hunt in fields for rodents and reptiles. They round out their diet with a small amount of plant materials.

They also adore koi and goldfish in home decorative pools; protective netting may be required if a pond attracts Great Blues. I witnessed one who took up residence near a wealthy man's lakeside estate, where several very fancy koi were kept in a very expensive Japanese-style pond complex. Both he and his butler were fascinated with the huge bird landing in the big firs around the neighborhood. Then some $250 koi went missing, and it wasn't until the pond maintenance workers put two and two together that the mystery of the missing fish was solved.

Heron sees human, does human see heron?

Great Blue Heron range widely - across the continent, into the high Cascade Mountain lakes, down to the Gulf Coast, Mexico and well into Canada and southern Alaska.

1 comment:

Anna J said...

I was linked to your blog from the Blogger Help Group and was excited to see a post about great blue herons! Our team has been spotting herons in Elkhorn Slough, a tidal marine estuary in the Monterey Bay National Marine Sanctuary. We are conducting sea otter and dolphin research with the help of Earthwatch volunteers. Our blog address is You and your audience might also find interest in the Earthwatch Institute. The website is