Newfoundland is home to two species of swallows: the Tree Swallow and the Barn Swallow. Both species can be found across the island during the spring and summer months before migrating south for the winter.
Tree Swallow
The Tree Swallow (Tachycineta bicolor) is a small songbird that breeds across Canada and the northern United States. It is blue-green on its back with white underparts. The Tree Swallow gets its name from its habit of nesting in tree cavities, particularly those made by woodpeckers. It will also readily nest in human-made nest boxes.
Tree Swallows arrive in Newfoundland in early May to breed. They prefer open areas near water, such as lakes, ponds, rivers, and marshes. Here they can find the flying insects that make up their diet. Some prime spots to observe Tree Swallows in Newfoundland include the Avalon Peninsula, Terra Nova National Park, and Witless Bay Ecological Reserve.
Tree Swallows build nests out of grasses and feathers inside their nesting cavity. The female lays 4-7 white eggs which hatch after about 2 weeks. The parents work together to feed the nestlings a diet of insects. After another 2-3 weeks, the young swallows are ready to leave the nest.
By late summer, Tree Swallows begin to gather in large flocks in preparation for their migration south. They spend the winter in the southeastern United States, Mexico, Central America, and the Caribbean. Tree Swallows migrate during the day and cover over 100 km each day. They return to the same breeding sites year after year.
Identification Tips
- Blue-green upperparts, white underparts
- Long, pointed wings
- Deeply forked tail
- Frequently observed perching on wires and poles
Barn Swallow
The Barn Swallow (Hirundo rustica) is the most widely distributed swallow species in the world. It is found across all of North America. The Barn Swallow is a very familiar sight in rural settings in Newfoundland during summer. Its habit of nesting inside barns and other structures gives this bird its common name.
Barn Swallows arrive in Newfoundland in May after completing their long migration from South America. Though they occasionally nest on cliffs, today most Barn Swallows nest inside barns, sheds, garages, under bridges, and in other manmade structures that mimic their original cliff-side sites.
Using mud pellets to construct their cup-shaped nests, Barn Swallows typically place their nests on a ledge or beam. The female lines the nest with grasses and feathers before laying 4-5 eggs. The eggs hatch after about 15 days. The nestlings are fed insects by both parents and leave the nest after about 20 days.
Barn Swallows capture flying insects on the wing. They can be observed flying over open fields, lakes, ponds, and other sites where insects are abundant. Barn Swallows gather in large flocks in late summer before migrating back to South America for the winter.
Identification Tips
- Blue-black upperparts, cinnamon underparts
- Long, deeply forked tail
- Frequently observed flying over open fields and water
- Nests constructed of mud pellets
Habitat and Diet
Tree Swallows and Barn Swallows both thrive in open habitat near water. This provides them with ideal foraging conditions as flying insects are abundant around water bodies. The diet of both swallow species is made up entirely of insects caught while flying.
Some of the insects commonly eaten include:
- Flies
- Moths
- Bees
- Wasps
- Beetles
- Mayflies
- Crickets
- Grasshoppers
Swallows will catch any small flying insect but they prefer slower moving species that are easy to capture. The availability of flying insects impacts the breeding success of swallows in a given year. More insects allow for higher rates of nestling survival.
Migration
Both Tree Swallows and Barn Swallows are long distance migrants. They breed during the summer months in Canada and the northern United States before heading south to spend the winter.
Most Barn Swallows from Newfoundland winter in northern South America in countries like Venezuela, Guyana, and Brazil. Some may travel as far south as Argentina. Tree Swallows winter from the southern U.S. through Central America and into northern South America.
In spring, swallows arrive back on their northern breeding grounds within days of the same calendar date each year. Their migration north is timed to coincide with the emergence of flying insects that the birds rely on to feed their young.
Tree Swallows and Barn Swallows migrate during the day, traveling in large mixed flocks. They may fly more than 300 km in a single day powered by their diet of insects. Bad weather can cause major mortality events during migration.
Population and Conservation Status
According to the North American Breeding Bird Survey, populations of both Tree Swallows and Barn Swallows are remaining stable or even increasing across most of their breeding range. However, Barn Swallow numbers have declined significantly in Ontario and British Columbia.
Some key reasons for the population decline in parts of Canada include:
- Loss of nesting sites – older barns being torn down or renovated
- Increasing use of pesticides reduces food supply
- Climate change disrupting migration timing
More research is needed to fully understand swallow population dynamics and the impacts of environmental changes. Maintaining suitable habitat, reducing pesticide use, and public education will support swallow conservation.
Species | Conservation Status |
---|---|
Tree Swallow | Least Concern |
Barn Swallow | Threatened (BC) |
Fun Facts about Swallows
- Barn Swallows can live for over 10 years but the average lifespan is 2-3 years.
- The forked tail and curved wings of swallows make them extremely agile flyers. They can make tight turns and swift evasive maneuvers.
- Tree Swallow parents may continue to feed their fledglings for several days after leaving the nest.
- Swallows migrate during the day travelling in large flocks that can number in the thousands.
- Barn Swallows line their mud nests with feathers to provide insulation. The feathers also help repel parasites.
- Swallows eat on the wing. They can snap up insects mid-flight and don’t need to land to eat.
- A group of swallows is called a “sweep”.
- Tree Swallow pairs often return to the exact same nesting site each year.
- Swallows help control insect pest populations including mosquitoes, flies, aphids, and grubs.
Conclusion
Tree Swallows and Barn Swallows are two of the most common and recognizable swallow species found in Newfoundland during the breeding season. They migrate long distances to South America each fall before returning again in spring to nest. Swallows reside in open, rural habitats where flying insects are abundant. They form large flocks in late summer before heading south. Populations of both species remain relatively healthy across most of their range.