YYZ Why?: Why the Leslie Street Spit was originally created

It boasts some of the best nature-watching in the GTA, but this oddly-shaped land formation, known as the Leslie Street Spit, is completely man-made.

Tommy Thompson Park is located on the land, which jets out five kilometres into Lake Ontario.

“So, the main spine, the main backbone of the park, is this brick and rubble from old construction sites, demolished buildings from the City of Toronto when they excavated for the subway extension, some of that material would have been disposed of here so, there’s a lot of history in the actual landform here,” said Andrea Chreston, project manager for Tommy Thompson Park.

The area was originally built for port-related infrastructure back in the 1960s, but since a site for port-related facilities was not ultimately needed, the land was left to sit and nature took over.

“Tommy Thompson Park and the Leslie Street Spit have evolved into a — and have been designated as — a globally significant and important bird area, so pretty much it’s a great place to come birding at any time of the year,” said Chreston.

On this day in mid-May, the staff at the park’s Bird Research Station is extremely busy.

Since the area is a critical stopover point for birds as they migrate over Lake Ontario between Toronto and New York state, the team will monitor dozens of bird species during spring migration. Migration monitoring consists of a daily census count and bird banding.

Across the park, in the trees, is the breeding ground for hundreds of black-crowned night herons.

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Several great egrets make their nests in these trees, too. This area is also home to the largest breeding colony of double-breasted cormorants in North America.

Tommy Thompson Park is open weekdays from 4 p.m. to 9 p.m., as well as weekends and holidays from 5:30 a.m. to 9 p.m. Tommy Thompson Park is open all holidays except Christmas Day, Boxing Day and New Year’s Day.

In an effort to protect the wildlife, pets and unauthorized motorizied vehicles, including e-bikes, are not permitted at the park.

In the Global News series YYZ Why?, Melanie Zettler sets out to answer why certain Toronto landmarks exist.