Stacey Cole's Nature Talks: Best to avoid heron nests until at least mid-June
Great Blue Herons occur throughout New Hampshire, but the vast majority of known colonies are located south of the White Mountains. Now that we are in the month of June, and great blue herons have begun their nesting season, let's take a closer look at their activities.
Here at the farm we see these magnificent flyers frequently as they travel from their nesting territory to their food gathering areas within the eddies and shallows of the Ashuelot River on our southern border. For as long as I can remember (and that is more than 70 years) we have watched herons glide over our fields and woods as they travel back and forth between their nesting areas and their feeding grounds in open water. These birds in flight are indeed a picture of grace. However, their aerial skill display can be spectacular when they deviate suddenly from their apparent flight plan.
Most great blue herons nest in colonies consisting of several mated pairs, frequently referred to as "rookeries," or "heronries." One usually finds their nests in remote areas, built high in dead trees standing in beaver ponds. On upland sites, they occasionally will build in live trees. It is probably best that these areas should not receive human attention until mid-June. Herons at the nest can be highly sensitive to disturbance, especially from bird watchers early in their breeding cycle. Heron colonies are frequently abandoned if disturbed by man. For the welfare of the herons, and to satisfy the interest of bird watchers, mid-June could be the best time to visit a heron colony.
From personal experience, it could also be the most interesting time for the observer. Young birds still are in the nest and are interesting actors when seen stretching and preening. Also, when they prepare for flight, they rise up high on their spindle legs and open and flap their wings. It should be noted that adult herons make frequent visits to feed their young by thrusting their food-filled beaks down the youngsters' gaping mouths.
A word of warning to visiting birders. If the adult birds become nervous because of a quick or surprise movement below their nest, they can and frequently do retaliate by releasing a rank-smelling stream some call "white-wash" that can spread over a large area. In anticipation of this possible surprise, an old umbrella might well prove most helpful.
Herons, hawks and especially turkey vultures all are marvelous travelers through the air. For the past several years around noon time, turkey vultures have appeared over the northern hill in back of our farm. Almost daily in good weather they circle our woods and meadows before drifting down or up river. Occasionally, though, they suddenly drop down and disappear into the woods. We often wonder what caused them to do so. We have speculated that they caught the sight or smell of carrion and descended for a meal. But can they actually receive a scent at such a height?
We may receive some help on this subject from one of my favorite authors, John Kieran, who wrote several books, including one of my favorites, "Footnotes on Nature," published by Doubleday & Co. in 1952. John Kieran may best be remembered as the host of a very popular television program, "Information Please."
In "Footnotes on Nature," he told of finding a turkey vulture feeding on "... the putrid remains of a defunct porcupine in the Berkshires." Kieran went on to tell of the time he was sitting around a luncheon table with the late Dr. Frank M. Chapman, the then dean of ornithological experts of North America, and others discussing this very question. Kieran wrote: "Dr. Chapman ... took vigorous issue with some other luncheon guests, also naturalists, who insisted that Turkey Vultures had no sense of smell and found all their food by sight. Dr. Chapman told how he had conducted experiments at his noted station on Barro Colorado in the Canal Zone and how vultures had located decaying meat that he had hidden; hence they had to locate it by a sense of smell. One of the non-smelling believers in the party then said that Dr. Chapman must have done a bad burying job with the bait and the birds suspected the presence of food where the ground had been disturbed. Dr. Chapman insisted that there was no outward or visible sign of the hidden meat. The debate waxed warm. I kept quiet, knowing nothing about the subject matter, though complete ignorance has not always been, in my case, a restraining influence. But if a turkey vulture can't smell out a concealed dinner, how did this one in the Berkshires find a dead porcupine lying just over a stone wall in the thick undergrowth of a dense wood in the full-foliaged month of June? There may be some other explanation than a sense of smell, ... but I couldn't think of it at the time," Kieran concluded.
Stacey Cole's address is 529 W. Swanzey Road, Swanzey.