Chimney Swifts over Downtowns

Nature Notes for August 19, 2011

You’ve probably heard them as you go about your business in downtown Port Hope or Cobourg in the summer. Chimney Swifts chattering overhead are a welcome sign of summer. They are still around, though, foraging for insects on the wing.

The Peterson field guide describes them as being shaped like “a cigar with wings” and most subsequent field guide authors have quoted this description. They are small, dark oblong-shaped birds with long curved wings. Their flight style is quite distinctive, since they fly with stiff, fluttery wing beats.

Although they superficially resemble swallows, and are often found foraging with swallows, their closest relative is thought to be the hummingbird. They spend most of their time in flight where they feed on flying insects and a few ballooning spiders.

Chimney Swifts often nest in chimneys, hence their name. Before buildings were available, they nested in hollow trees or caves.

Their nests are a small, rather flimsy, flat saucer of twigs glued together and to the supporting vertical surface with swift saliva. The birds collect the uniform sized twigs in flight.

The nests of an Asian species of swift are prized as the main ingredient of birds nest soup. This very expensive soup is really just cooked swift saliva!

Swifts have very short, weak legs. Their toes are specially adapted for clinging onto vertical surfaces and the edge of their nests. As well, they have stiff projections from their tail feathers which aid in keeping balanced when they perch.

As with all aerial foragers, Chimney Swift populations showed a definite population decline between Ontario’s two Breeding Bird Atlases. As with many other species, this decline is thought to be due to habitat loss.

However, some Chimney Swift habitat loss has to do with modifications to human built chimneys. Many chimneys built in the nineteenth century are no longer in use and many have been taken down or closed off. Changing fire codes require metal chimney liners. Many chimneys are capped to prevent access to animals and birds which humans consider pests.

In some places, artificial structures are being erected to provide Chimney Swifts with suitable nest sites. Two have been erected in Ferris Provincial Park in Campbellford.

As a bird bander, I have had the opportunity to view many species of small birds up close. However, my one close encounter with Chimney Swifts was in a decidedly non-naturalist setting. On September 4, 2002, Northumberland Players held a reception at the Firehall in Cobourg to publicize the upcoming season. At that time, the Firehall was not air conditioned. It was a warm evening, so all the windows were open. Suddenly into the midst of the wine and cheese reception flew two Chimney Swifts. They were a bit confused and crashed into the wall opposite the open windows.

Most of those present thought that they were bats and became a bit hysterical. I leapt into the fray, picked up the frightened birds and carried them downstairs to the parking lot. One flew off immediately. The other one needed a bit of time to recover its senses, but after a few minutes, it, too, recovered and flew off to join the other swifts swirling around Victoria Hall.

Chimney Swifts have started to migrate and most will be gone in about a month. Most winter in South America, in Peru and western Brazil.

In Praise of Presqu'ile Provincial Park

Nature Notes for August 5, 2011

It is easy to take for granted natural areas that are near at hand. I have spent more time than usual in Presqu’ile Provincial Park this summer.

This park contains a large variety of habitats in a rather small area. It has mature mixed woods, good quality marsh, sand beaches, Pannes, old field, open lake, the more protected Presqu’ile Bay and offshore islands.

Since records have been kept, 333 species of birds have been recorded in the park. Some are rare and would be unusual to encounter more than once in one person’s lifetime. Some are regular visitors during the passage of migration. Some breed in the park and raise their families here.

Presqu’ile’s new Marsh Boardwalk allows visitors a good look at many marsh birds which would otherwise only be seen from a canoe. Regularly, Least Bittern have been reported this summer from the area of the first observation platform. This small heron is very secretive and one is lucky to get even a fleeting glimpse.

The larger American Bittern could also be heard, and sometimes seen, from the boardwalk. This heron is also somewhat secretive, but it has a loud voice. At dawn and dusk, a number of them could be heard singing their “chunk-a-lunk” song.

Presqu’ile’s marshes have quite a high density of MarshWrens. Throughout the season, they could be heard singing their loud trill. If an observer was willing to wait for a little while, he was almost certain to catch sight of this active little bird. While canoeing in this marsh, we were able to approach many Marsh Wrens quite closely.

There is also a good population of Swamp Sparrows in Presqu’ile Marsh. These males sing a different sort of trill than the wrens, but also have a loud song.

To our surprise, we found a family group of Common Loons just off the Fingers in Presqu’ile Bay. Until this summer, I was unaware that a pair of loons has been nesting for several years somewhere in the marsh. I had thought that they preferred the smaller lakes in cottage country. This indicates that there are areas of the marsh that are undisturbed by motorized watercraft.

Over the marsh, many swallows could be found hunting. Most were Barn and Tree Swallows, but there were a few Purple Martins.

Several species of birds that breed on the offshore islands pass over on their way to and from foraging areas. The largest proportion of these birds are Ring-billed Gulls. Other colonial birds nest here too: Herring and Great Black-back Gulls, Caspian and Common Terns, Great Blue Herons, Great Egrets, Black-crowned Night Herons and Double-crested Cormorants.

Caspian Terns, large fish-eating, gull-like birds with a raucous voice and a huge orange bill, were often seen fishing in the open channels of the marsh.

Numbers of their smaller relatives, Common Terns, have experienced a precipitous decline in recent years. Presqu’ile used to have a very large colony of Common Terns, but they are mostly gone now, pushed out by Ring-billed Gulls. The Ring-bills winter further north, so arrive back on the breeding colonies earlier than the terns, and grab all the good nesting sites.

At this time of year, birders head to Presqu’ile in hopes of finding south-bound migrant shorebirds. Twenty-five species of shorebirds are regular in the park; forty-two have been reported over the years. Presqu’ile’s beaches provide habitat for these birds, a habitat that is rather scarce in Northumberland County. So far, there have been very few shorebirds reported this summer. By the time this column appears, their numbers may have increased.

The knowledgeable staff naturalists at the Park provide interpretive programs all year for those who want to learn more about the natural features of this park. This column has mentioned only birds in a couple of habitats. There are also butterflies, dragonflies and damselflies, a great variety of vascular plants, turtles, frogs…… The list is very long.

For more information about programs in the park, check out www.friendsofpresquile.on.ca