Yes, bobolinks are found in Ontario during the breeding season. The bobolink is a small songbird that migrates from South America to breed in grasslands across much of eastern and central North America each spring and summer. In Ontario, bobolinks arrive in May to nest and raise their young before departing in late summer.
What is a Bobolink?
The bobolink is a medium-sized blackbird measuring 15–18 cm in length with a wingspan of 20–27 cm. Males have a distinctive appearance during the breeding season, with a black front, white scapulars and rump, and a buffy nape and crown. This contrasting plumage pattern gives the males their nickname of “skunk birds.” Females and juveniles are mostly brown-streaked overall.
Bobolinks get their name from their bubbly, jabbering song, which sounds like they are saying “bob-o-link” as they fly over fields. Their scientific name Dolichonyx oryzivorus means “rice eating bird,” referring to their habit of eating rice and other grains while wintering in South America.
Bobolink Habitat and Diet
Bobolinks nest in large open grasslands, such as hayfields, meadows, and pastures. They build cup-shaped nests low in dense vegetation, concealed by the leaves and stems around it. Females lay 3-7 eggs that hatch after 11-14 days. Both parents feed the young a diet consisting mainly of insects, especially caterpillars.
Later in summer, bobolinks switch to eating seeds from grasses and other plants. They have sturdy beaks adapted for cracking open seeds. During migration and wintering, they often flock together to feed on rice, sorghum, and other grains in agricultural fields and marshes.
Bobolink Population and Conservation Status
Bobolinks have experienced significant population declines in recent decades. Between 1966-2015, the overall bobolink population in Canada declined by 88% according to the North American Breeding Bird Survey. Habitat loss from the conversion of hayfields and pastures to more intensive agriculture is a major threat. Earlier and more frequent hay mowing also destroys many nests before young can fledge.
Bobolinks were assessed as Threatened in Ontario in 2010. Partners in Flight estimates there are 68,000 breeding pairs in Ontario, out of 1.1 million total in Canada. They are listed federally in Canada under the Species at Risk Act as Threatened. Conservation efforts focus on protecting grasslands from development and delaying mowing until later in summer after peak breeding season.
Bobolink Distribution and Migration
Bobolinks breed across southern Canada from British Columbia to Nova Scotia, and south to northern California, Nevada, Utah, Nebraska, Iowa, Ohio, Maryland, and New Jersey. The highest numbers breed in the prairie provinces and Great Lakes states.
Season | Location |
---|---|
Breeding (May – July) | Fields and grasslands of central North America |
Fall Migration (August – October) | East coast of North America |
Winter (November – March) | Southern South America |
Spring Migration (April – May) | Through Central America and eastern North America |
Bobolinks undertake a long distance round trip migration each year between their breeding grounds in central North America and wintering areas in southern South America. They migrate in large flocks, stopping to rest and feed in areas with suitable habitat along the way.
Fall Migration
After breeding, bobolinks gather in large flocks and move south through the eastern United States to the Atlantic coast. They fly long distances over open water to reach coastal South America.
Wintering Grounds
Bobolinks spend the boreal winter in grasslands, agricultural fields, savannas, and marshes from southern Bolivia and central Brazil south to northern Argentina. They form large roosting flocks at night.
Spring Migration
In April and May, bobolinks fly north through Central America and along the Gulf Coast and Atlantic Coast to reach their breeding grounds again. Spring migration progresses more quickly than in fall.
When Do Bobolinks Arrive in Ontario?
Bobolinks are some of the later spring arrivals in Ontario, typically appearing in early to mid-May. The timing of their spring migration is closely tied to the availability of suitable habitat at their breeding grounds further north.
In southern Ontario, the first bobolinks usually show up around May 10-15. However, arrival dates can vary by two weeks or more from year to year depending on weather conditions. Males tend to arrive first to establish territories, followed shortly after by females.
Here are average spring arrival dates for bobolinks in select locations across Ontario:
Location | Average Arrival Date |
---|---|
Windsor | May 13 |
Toronto | May 18 |
Ottawa | May 19 |
North Bay | May 23 |
Thunder Bay | May 27 |
Bobolinks arrive earlier in southwestern Ontario and later in northern parts of the province. But by late May, they can be found across Ontario wherever suitable grassland breeding habitat exists.
Where Do Bobolinks Breed in Ontario?
Bobolinks breed in open grassy areas scattered across much of southern and central Ontario. Some of the best places to find bobolinks in breeding season include:
– Hayfields and pastures: Bobolinks favor relatively tall grasslands with dense cover for concealing their ground nests. Uncut hayfields and lightly grazed pastures provide ideal habitat.
– Grasslands preserves: Protected natural areas like Ojibway Prairie Complex in Windsor, rare Charitable Research Reserve in Cambridge, and Grasslands National Park in southern Ontario maintain breeding bobolink populations.
– Airports: The expansive grasslands surrounding airports provide surrogate bobolink habitat, like at Toronto International Airport and Ottawa International Airport.
– Agricultural buffer strips: Uncropped buffers beside agricultural fields are managed to provide nesting habitat.
– Old fields and meadows: Overgrown vacant lots, reservoir edges, reclaimed mines, and other idled grassy areas attract bobolinks.
Bobolink densities tend to be highest in southwestern Ontario counties like Essex, Kent, and Middlesex. But they can be found in suitable habitat as far north as Kenora, though in lower numbers. Sightings become more scattered in northern Ontario boreal forest.
What is the Bobolink Breeding Season?
Bobolinks breed during the summer months after arriving at their nesting grounds in May and June. The typical bobolink breeding season is:
– Territory establishment: Late May – early June. Males return first and advertise territories with flight songs and calls.
– Pair formation: Mid May – late June. Females arrive approximately 1-2 weeks after males. Pair bonding occurs after females settle.
– Nest building: Late May – early July. Female constructs nest out of grasses and forbs in dense vegetation.
– Egg laying: Early June – late July. Clutch size ranges from 3-7 white eggs.
– Incubation: 12-14 days. Female incubates eggs. Male guards territory and brings food.
– Nestlings: Both parents feed nestlings. Young fledge about 10-17 days after hatching.
– Fledging: June – August. Parents may raise 2-3 broods per season. Young are independent by 30 days old.
The timing of nesting activities depends on arrival dates and can vary across Ontario. Nesting starts earlier (May-June) in southern regions and later (June-July) in the north.
What Threats Do Bobolinks Face in Ontario?
Although bobolinks continue to breed in Ontario, their populations here and elsewhere in Canada have declined significantly since the 1960s mainly due to habitat loss. Some of the major threats facing bobolinks in Ontario include:
– Hayfield harvesting: Mowing fields before young fledge destroys many nests and young. Estimated up to 72% of nests can be lost to haying.
– Habitat conversion: Draining wetlands and converting pastures and meadows to crops destroys breeding sites.
– Development: Housing, commercial, and industrial development eliminates grassland habitat.
– Nest predation: High rates of nest losses occur due to predators like raccoons. Fragmented habitats make nests more vulnerable.
– Pesticides: Exposure to pesticides on wintering grounds in South America may harm bobolinks.
– Climate change: May cause habitat range shifts that could impact bobolink populations long-term.
To conserve bobolinks in Ontario, protection and management of remaining grassland habitats is essential. Preventing further habitat loss and working with landowners to delay mowing are key priorities identified in Ontario’s recovery strategy.
Interesting Facts About Bobolinks
Here are few additional interesting facts about bobolinks:
– Male bobolinks can have up to six mates in one breeding season. Females usually raise one clutch on their own but may nest again with a new male.
– Nestling bobolinks can eat up to 1,100 caterpillars per day, provided by both parents regurgitating food.
– Adult bobolinks migrate in large flocks, sometimes numbering in the tens or hundreds of thousands of birds.
– Bobolink eggs are white with dark brown spots, akin to a miniature chicken egg. The female alone develops a brood patch to incubate them.
– Their songs vary regionally across North America – northeastern birds have a more complex repertoire than western birds.
– Bobolink populations show periodic fluctuations. Numbers crashed during the late 1800s but rebounded in the early 1900s.
– They are considered agricultural pests in parts of South America where they feed on crops like rice and sorghum in winter.
– Bobolinks are the only grassland songbird in Ontario to have a national recovery strategy due to their severe population declines.
Conclusion
In conclusion, bobolinks are migratory songbirds that breed in Ontario’s remaining grasslands and hayfields each summer before returning to South America for the winter. Their populations have declined significantly in recent decades due to habitat loss and are now designated as Threatened both provincially and nationally. Conservation efforts to protect and manage meadows and pastures are crucial to ensuring bobolinks continue nesting in Ontario into the future. Though they face challenges, bobolinks still add their bubbly songs and colorful presence to our fields each spring.