There is a heronry near the Grand River close to the community of Elora. I saw it first last spring and found it very interesting to see these large water birds nesting communally in tree tops. Great Blue Herons have been reported around the region for at least three weeks but after a couple of trips to the heronry, I had yet to see one. Sunday afternoon was sunny and seasonally warm when I finally found the birds.
The heronry or rookery is in a swamp and I counted about twenty nests in the leafless trees. I never heard the term "heronry" and looked up the definitions of both terms. (source)
n. pl. her·on·ries
A place where herons nest and breed.
n. pl. rook·er·ies
a. A place where rooks nest or breed.
b. A colony of rooks.
2. The breeding ground of certain other birds or animals, such as penguins and seals.
3. Informal A crowded and dilapidated tenement or slum.
Rooks are Old World birds that resemble crows. They nest in tree top colonies as well, but they are not found in North America. So I will call the heron colony a heronry from now on.
The heronry is on private property along a country road. Unfortunately many people now know about it and I watched three car loads of curious onlookers arrive at different times and tramp loudly through the bush to the base of the trees. The Herons all flew away leaving the nests unattended for half an hour. I do not know if they have eggs laid yet. I waited in the car until they returned and then took these photos from the road. A Red-tailed Hawk circled above the heronry while I was there and would have considered any unattended eggs or young birds a fairly found meal.
The Herons returned in pairs and were very amorous. Mating behaviour can be precarious when two large birds are perched on a nest of sticks sixty feet or more in the air. The nests are of varying sizes as seen in the picture below. This nesting season is very important and disturbing the birds may endanger their young. The other large heronry along this river is on an island and is accessible only by canoe.
We have had about half a foot of snow in the past twenty-four hours accompanied with high winds. I am amazed at the ability of birds to adapt to the weather variances we experience here in the spring.