They say that “if you build it, they will come” but when it comes to restoring a natural area and creating habitat, it’s not that simple. That’s why the ecologists at Conservation Halton are so impressed with the bird communities that are making their homes in the wetlands, grasslands and forests of Glenorchy Conservation Area.
Glenorchy Conservation Area is a natural area in north Oakville, made up of about 401 hectares (990 acres). The area is owned by the province of Ontario but, because it is such an important part of our watershed, the province has partnered with Conservation Halton to protect, restore and enhance the natural features and ecological functions of this area. For the last nine years, restoration ecologists and foresters at Conservation Halton have worked to restore 176 hectares (435 acres) of Glenorchy and most of this restoration is complete, including 104 hectares (257 acres) of forest, 50 hectares (123 acres) of grassland, 15 hectares (37 acres) of riparian area and 6 hectares (15 acres) of wetland.
With this restoration has come many new communities of birds. In order to monitor how the bird communities at Glenorchy change in response to the restoration, Conservation Halton has been conducting bird surveys for the past five years. About 60 species of birds have been observed at Glenorchy during these surveys, including many that are rare, threatened or in decline.
Some of the first birds to make their homes in Glenorchy were the wetlands birds.
Ten years ago, much of Glenorchy was vacant land with some swales, which are low, shallow stretches of land, like a ditch on the side of the road, that are often wet and marshy. We created dips and bends in these swales, which slowed the flow of water through them, and formed depressions in the soil, which filled with water and became wetlands.
Today, even at the end of summer, there is still water flowing through these creeks and lingering in these wetlands. There are cattails growing, insects flying around and barn swallows swooping down to eat them. There are fish flitting through the reeds, frogs croaking and herons feeding.
This new habitat being created is not unlike a new neighbourhood being built and the bird communities finding their way to this habitat are not unlike the families making their way to a neighbourhood.
In the restoration of Glenorchy, the wetlands were the first kind of habitat to be created and took the least amount of time to become inhabited—just like those pockets of townhouses in a new neighbourhood. It didn’t take long for the wetlands to fill with water and for cattails to begin to grow. This combination of water and cattails are the ideal habitat for a number of bird species, such as Marsh Wren, Sedge Wren, Virginia Rail and Pied-billed Grebe.
The ecologists at Conservation Halton were especially pleased to find that a family of Pied-billed Grebes, which are uncommon in Halton, had moved in, nested and raised their young in the new wetland at Glenorchy just four years after it was created. The homes that Pied-billed Grebes build are quite unusual. To make their nests, these birds dive down to the bottom of the wetland or marsh, pick up dead and decaying plant matter and pile it up until it forms a dense mound that is able to float on the surface of the water. They will then anchor their nest to the stem of some other wetland plant that is rooted in the ground under the water. Though Pied-billed Grebes are one of the more secretive birds, the grebes can be seen diving for fish and carrying their young around on their backs at Glenorchy.
“In our region, most species of wetland birds have been on the decline in recent decades. It’s amazing that we were able to restore a wetland and then, just a few years later, have these habitat-specific birds using this wetland,” says Nigel Finney, Watershed Restoration Planner at Conservation Halton.
The grassland birds are also starting to make their homes in Glenorchy.
Before the restoration, there were just a few bird species, such as Horned Lark, Spotted Sandpiper and Killdeer, that were able to nest in the fields of Glenorchy.
Today, a large area of Glenorchy has been turned into grassland and is becoming home to many species of sparrow, such as Field Sparrow, Song Sparrow, Savannah Sparrow, Vesper Sparrow, Clay-Coloured Sparrow, which is rare in Halton, and Grasshopper Sparrow, which is uncommon in Halton and a species of special concern.
Grasshopper Sparrow are unique in that they prefer grasslands with shorter plant species and actually build their nests on the ground. Their nests are made of grass and often include a roof, also made of grass. These sparrows also do their foraging on the ground—for grasshoppers, of course. These sparrows actually paralyze the grasshoppers by pinching their thorax and then shake the legs off the insects before feeding them to their young. Grasshopper Sparrows have been on the decline for many years, as grassland area in Ontario becomes less and grassland habitat is lost. The grasslands at Glenorchy will restore some of this habitat for Grasshopper Sparrow and other species of grassland birds.
If wetlands are the townhouses of a new neighbourhood, grasslands are the detached houses with the two-car driveways and the backyard pools—they take a bit longer to build and are much more spread out but they are a perfect home for many bird communities. In fact, many bird species will only breed in a grassland area if it large enough.
“We could have created many small grassland areas throughout Halton but one large grassland provides more value to biodiversity, and this was the perfect opportunity to create one,” Finney says.
The last to move to Glenorchy will be the forest birds.
Before the restoration, there was some forested area at the north and south ends of Glenorchy, so, with our partners, Conservation Halton planted more trees, shrubs and ground cover plants to make these areas larger—but, unlike in the wetlands and grasslands, it will be a while before we see forest birds in these areas. Most of the trees were planted from seed, with some areas planted from saplings, so it will be many years before the trees are large enough and the forests are mature enough to be habitat for most forest bird species. Until then, the grasses and shrubs in these areas will provide early habitat for some species of birds and other wildlife as is transitions from a meadow to a thicket and then to a forest.
Think of the forests as the custom homes with the four-car garages, the tennis courts and the indoor pools—they take a long time to build and cover the most amount of ground but, eventually, they will be home to some special species of birds.
It is hoped that some of the bird species that already live in the forests that are there, such as Eastern Wood Peewee and Wood Thrush, both of which are species at risk, will increase in number as the trees mature and the forest cover grows.
The wetlands, grasslands and forests of Glenorchy have become habitat for many species of birds but these natural areas will help protect another kind of habitat—our own. Natural areas like Glenorchy reduce the vulnerability of our communities, strengthen the resilience of our watershed and better enable us to mitigate and adapt to the effects of climate change. Though it is currently closed to the public, Glenorchy will also become a natural and recreational asset to our communities, once it is open.
Conservation Halton is dedicated to the restoration and conservation of Glenorchy and staff are looking to secure the funds needed to maintain this natural area. If you would like to support the Glenorchy Conservation Area, please contact Brian Hobbs at email@example.com.
Last modified: September 19, 2017