The birds are most raucous when parents return with food, sending the chicks into a noisy frenzy. Otherwise, the bird’s main call sounds like a person crying for Frank while being strangled.
The herons have returned to the west side of the park to build a colony of nests atop sequoias and copper birches. These are near Goodacre Lake, a man-made pond within sight of Douglas Street, just five blocks from the terminus of the Trans-Canada Highway.
A team led by Trudy Chatwin, a rare and endangered species biologist for the provincial Environment Ministry, spent hours in the park patiently counting heron nests. They spotted 54, and more have been built since the count concluded a fortnight ago.
Some chicks are already six to eight weeks old. Meanwhile, other pairs of adults oddly continue to build nests.
In years past, the birds established a heronry atop towering Douglas firs. The colony lasted about a quarter-century with as many as 110 nests at the peak.
So many birds led to the accumulation of droppings so acidic as to destroy the underbrush below the trees. (“After a year or two of dropping guano,” Mr. Hook said, “it gets a bit ripe.”) As well, root rot made it necessary to cut down 11 cedar trees.
The lessening of crown cover made the herons more visible and more vulnerable.
Five years ago, the birds came under assault from eagles. Eggs were destroyed, chicks killed. The colony was devastated.
Some thought the destruction was the work of a single adult eagle, dubbed Birdzilla, whose intent it was to wreak havoc among the herons.
Janis Ringuette, a nearby resident and an expert on the history of Beacon Hill Park, dismisses the theory of a lone rogue eagle. She witnessed a juvenile eagle dining on a heron egg, so she thinks the Birdzilla theory is birdbrained. Instead, she thinks the colony suffered from the birds being exposed.
“The nests were laid out like a buffet in those Douglas firs,” she said.
The herons abandoned 71 nests in May, 2007. The birds are believed to have moved seven kilometres north to Cuthbert Holmes Park along the Colquitz River in Saanich.
Herons are not banded, so no one knows for sure which birds are which, but 19 nests were re-established at Beacon Hill Park last year. Today, few if any herons are spotted at Cuthbert Holmes. The herons, likely chased away again by eagles, have resettled closer to downtown.
Herons prefer quiet spots and the Victoria park is a busy one, but the waterline at the nearby Dallas Road bluffs along the Juan de Fuca Strait provides a tempting selection of daily hors d’oeuvres.
Great Blue Herons are listed as a vulnerable species in the province. The eggs and nests are protected under provincial law, as are the trees being used as nests. An egg hatches about four weeks after being laid, while the chicks stay in the nest for another two months before they can fly.
The magnificent Ardea herodias has blue-grey body feathers, a yellow bill, a white head and black stripes above each eye. An adult stands as tall as a Grade 3 pupil with a wingspan stretching as wide as Steve Nash is tall.
“Like pterodactyls,” Ms. Ringuette said.
The city has encouraged the return to Beacon Hill. Red alders, cottonwoods and big-leaf maples have been replanted in the area previously fouled by their droppings. It will take a decade of growth before those trees are tall enough to contribute to a protective canopy.
As well, city crews placed piles of twigs on the ground in the park to encourage the herons in their nest building.
“Everybody loves them,” Mr. Hook said. “People come from thousands of miles away to watch them.”
The heronry, best observed from a polite distance, is the city’s loudest – and stinkiest – tourist attraction.
Special to The Globe and Mail
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