A Black-Crowned Night Heron at Tommy Thompson Park
Tommy Thompson Park in Toronto is recognized worldwide as a significant habitat for breeding waterbirds, and during the summer months, when fewer songbirds make the Leslie Street Spit their home, birdwatchers will still be rewarded with glimpses into the lives of the colonial species, one of which includes the Black-crowned Night Heron.
It seems an unlikely location for such large colonies of waterbirds there within a short distance of downtown Toronto, but the 500-hectare urban wilderness of Tommy Thompson Park has naturalized into a mosaic of varied and suitable habitats that support many different bird and animal species.
The Black-crowned Night Herons nest in the deciduous woods that grow on Peninsulas A, B and C on the west side of the man-made Spit, a habitat that provides the necessities of life for this species: proximity to water for foraging and ample vegetation for cover.
It was rather an accident that Bob and I found ourselves so close to some of these impressive birds. We had been searching for different species of butterflies, and found that the great stands of Canada Thistle were a magnet for the colourful Red Admiral Butterflies whose wings were glowing backlit as they were with the noonday sun.
No sooner had we hopped off our bikes for a closer look and better angle from which to photograph the delicate beauties when Bob drew my attention to a Black-crowned Night Heron less than 20 feet away.
We moved a little closer to obtain an unobstructed view of the bird…
and that is when we realized that there were several others in the immediate vicinity.
Black-crowned Night Herons are quite impressive looking birds. As their name suggests, they have a glossy, black crown with the black feathers extending along the back of these birds to create a strong definition between the remaining white and pale grey plumage. There is no overlooking the strong, stout bill of this bird, also black in colour, and the remarkable red eyes that seem to pierce right through you.
In breeding season, Black-crowned Night Herons are adorned with two or three long, white plumes that extend from the nape of the neck. We could make out these attractive plumes on several of the birds we saw that day. Reaching a length of close to 25 centimetres (almost 10 in), these slender feathers are raised when greeting other birds or during courtship displays.
Black-crowned Night Herons in full breeding plumage possess these white feathery plumes, and their yellowish-green legs become pink. It was mid-July when we observed these birds, so the legs and feet that were pink earlier in the season have returned to this colour and will remain so for the remainder of the year. We had observed some of these Herons on the nest one Mother’s Day in May, and all of the birds exhibited pink legs at that time.
Because Black-crowned Night Herons traditionally forage for food in wetlands between dusk and dawn explains our luck in finding them perched during the daylight hours. Part of their diet consists of the eggs and young of other heron species that share the wetlands, so their nocturnal activity makes them less vulnerable to harassment by the other herons. Fish make up the bulk of their diet, but they eat a wide range of creatures including snakes, amphibians, mollusks and rodents.
The squat, thick proportions of Black-crowned Night Herons give them a hunched countenance when at rest, but when hunting, their necks are extended and they more resemble other long-legged wading birds. In the low-light conditions present between dusk and dawn, these Herons rely on their exceptional eyesight to locate prey that is then snatched up with a swift grasp of the bill, thoroughly shaken to stun or kill it, then manipulated in the bill and swallowed head first.
Black-crowned Night Herons are social birds explaining why we found several roosting together. They would remain hunched and stationary on the tree limbs or hidden in amongst the foliage until it was time to fly out to the marshes or mudflats as the late afternoon sun was sinking below the horizon. Although they might appear dull and lethargic as they assume their daytime posture, we found them quite handsome in their tri-coloured plumage with the soft white plumes flowing gracefully in the breeze.
Related:
A Long-eared Owl at Tommy Thompson Park