We may be used to seeing herons wading stealthily in water in pursuit of fish or standing frozen and statuesque at the edge of a marsh. While they’re right at home down low in the world of frogs and fish, herons often nest high in trees in nests made of sticks and twigs, and often in very large, exciting, and noisy colonies. Some densely packed heron colonies may harbor more than a thousand nests, with many nests crowding the limbs of each cottonwood, maple, or pine.
To see a rookery of nesting herons is an exciting tangle of raucous sounds and dancing grace, as herons fly in and out, display, pass sticks to their mates, and tussle over territory in crowded confines. But as we grow attached to a rookery, we may be saddened to realize that herons, by the act of choosing a nest site, are often destined to destroy it. The acidity of heron droppings begins to kill the nest trees, and after 1 or 2 years, the colony begins to fall apart.
See also Bird Watch: Great Blue Heron
In an attempt to entice herons to stay, some conservationists band together to erect heron nest platforms that tower several feet into the sky. Workers drive lightweight tripod platforms or, more traditionally, heavy utility poles into soggy lake sediments as support scaffolding for stick nests.
In northern latitudes, this work is almost always done on a stable platform of lake ice, long before the herons return in the spring. Almost always, a starter bundle of sticks are put in place, encouraging birds to continue building and to take up residence.
Taking on such a challenge is a job best suited for a team of ambitious people (like a highly motivated lake association) with access to some serious tools. Some projects even require truck-mounted augers and utility cherry-pickers. In addition to the benefits to herons, such platforms are sometimes chosen by fish-eating birds of prey, such as ospreys and bald eagles, and may be specifically designed and intended for such birds.