Friday 26 May 2017

May Birding in Northumberland



Nature Notes for May 26, 2017

Birding in May! 

This month is the highlight for many birders, since it marks the return of those jewels of the forest, the wood warblers. As they return from wintering grounds in the tropics, these colourful, tiny birds can turn up anywhere.

This year’s northward migration has been slowed by north and east winds and many rainy days. These tiny birds migrate mostly at night, which is thought to protect them some from avian predators.

Several mornings in the past month, there have been a few warblers in my garden. Perhaps I’m lucky to live not too far inland from the Lake Ontario shore. Migrants are often tired and come to the ground to rest and eat after flying all night.

Most of these birds are in transit and do not nest in Northumberland County. They are headed to the boreal forest to take advantage of abundant insects in the northern summer. These insects are the principle food for their young.

Some of the most common warblers that do breed here are Yellow Warbler (yellow with chestnut streaks on the breast), Common Yellowthroat (males are mostly yellow with a black mask across their eyes) and Chestnut-sided Warbler (yellow crown, white cheeks, with chestnut flanks).

Several people who have noticed other colourful birds in their yards have contacted me recently. Male Rose-breasted Grosbeaks are particularly striking with their black head, black and white on wings, back and tail and a splash of red on the throat and upper breast. The females are a drabber brown and white which makes them less obvious when on the nest.

 Migrant Rose-breasted Grosbeaks have been visiting backyard feeders.
Photo © Rob Lonsberry Photography

The bright blue of male Indigo Buntings always catches one’s attention. The blue in the feathers is iridescence, not a pigment, so the colour depends on the angle of the light. Like the Rose-breasted Grosbeaks, the females are a much more drab brown.

Baltimore Orioles have been singing in my neighbourhood for the past couple of weeks. It is amazing how a bright orange and black bird can become invisible when it lands in a green tree.

These latter three species do nest locally, but they are more obvious on their return in May when the leaves have not fully opened and the males are singing vigorously. Once a territory is established and the birds are feeding young, they often go quite quiet so as not to draw the unwanted attention of predators to the nest.

Last weekend was Presqu’ile Provincial Park’s Warblers and Whimbrels weekend to celebrate the return of the migrants. Whimbrels are large shorebirds which usually pass through Ontario around May 24, on their way to nesting grounds in the Arctic. Other shorebirds are migrating through also. These include Dunlin, Ruddy Turnstone, Least Sandpiper, and Semipalmated Plover.

Many shorebirds have very long migrations, from southern South America to breeding grounds in the Canadian Arctic. The birds that stop here are having a difficult time this year because of the high water levels. Beaches are flooded as are many of the rocky jetties where the birds sometimes land to rest and feed. Some of the shorebirds may use wet agricultural fields.

The rare Piping Plovers will have a difficult time finding dry beaches on which to nest this year. The male of the pair that nested at Presqu’ile last year did return about a month ago, but has not been seen recently. (This bird is colour banded so it can be identified.) If the bird can’t find a dry beach, it may not breed in 2017.

Spring migration will continue through the first week of June. Perhaps readers will enjoy some of these colourful birds.