A bald eagle family is drawing enthusiastic visitors to Cootes Paradise in Hamilton, Ont. This is the first time since the 1950s a pair of eagles has successfully nested on the Canadian shore of Lake Ontario. Danny and I went to have a look on the gorgeous Saturday afternoon of Easter weekend. My camera was inadequate for the task of photographing the distant nest. The tree is close enough viewing for a descent pair of binoculars and distant enough to avoid disturbing the birds. We spent about 15 minutes watching one adult perched on the side of the huge nest, and a small head occasionally bobbed above the rim. There is a photo of the adult pair on the nest in a Hamilton Spectator article.

About 200 pairs of bald eagles nested in southern Ontario in the early 1900s, but their population plummeted for several reasons. Widespread use of DDT insecticide from the 1940s to the 1970s virtually ended any successful breeding in this province. It made the eagles’ eggs too fragile and the adults would unwittingly crush them.

Not far from where I grew up, a pair of eagles nested at Fox Creek Conservation Area near the shore of Lake Erie in the 1970s. It was one of the few nests left in Ontario, but according to an Environment Canada fact sheet, none of them successfully hatched young at that time. One day one of the great birds landed in a huge dead poplar tree on our property overlooking the lake. I had never seen one before, and it was an unforgettable thrill.

Since DDT was banned in the 1980s, bald eagles have made a slow recovery in this province. In 2011 in Southern Ontario, at least 69 young were produced by 41 known successful nests, according to a report from the monitoring program. Not all survived.

In the 1990s, Royal Botanical Gardens began managing and restoring the heavily polluted wetland at Cootes Paradise at the west end of Hamilton Harbour between Hamilton and Burlington. In 2009 this progress drew the attention of the pair of eagles, which has attempted to nest each year since without success.

But late last month intense activity drew attention to the fact that two eaglets had hatched in the nest. Fortunately the nest can be discretely but openly viewed from the Marsh Boardwalk. Visitors can gain access from the RBG Arboretum. Parking costs a loonie for one hour. Directions to the boardwalk are provided at the nature centre there. It requires a rigorous hilly 20-minute walk. To the right of the boardwalk stand some dark-silhouetted white pines in the distance containing the shabby, conspicuous nest.

Bald eagles are huge, one of the largest raptors in North America, with adult wingspans of 2 metres or more. They also have built the largest recorded tree nests of any animal. They are well worth a visit. Based on usual fledging behaviour, there should be plenty of activity around the nest until about the end of June. They offer tangible and dramatic evidence of what good conservation practices can achieve.

[Edited May 6, 2013: This post originally stated erroneously that Cootes Paradise was located in Burlington, Ont. Actually it is entirely within the city of Hamitlon.]