What's a Whimbrel?

Nature Notes for May 27, 2011

“I know what a warbler is, but what’s a Whimbrel?” That was a query I fielded last weekend at Presqu’ile Provincial Park’s annual Warblers and Whimbrels weekend.

A Whimbrel is a large shorebird with a long downward curving beak. If they appear in Northumberland County, they usually come around May 24. Six birds appeared for a short time on the beach at Presqu’ile on Sunday, May 22.

They used to come so regularly to Willow Beach, a Lake Ontario shoreline beach west of Port Hope which is now largely eroded, that the local field naturalists club adopted it as their logo.

The old name for a Whimbrel was “Hudsonian Curlew”. Hence, the club’s newsletter is named The Curlew.

Like so many of the birds I write about, the Whimbrel has experienced a huge population decline. Studies done by the Center for Conservation Biology (CCB) at the College of William and Mary and The Nature Conservancy (TNC) recorded about a 50% decrease in Whimbrels counted in a staging area in the Delmarve Peninsula between studies done in the mid-1990s and 2008-2009.

Like many shorebirds, Whimbrel are known to nest in the high Arctic and winter in the south, some as far south as South America. Until very recently, it was thought that birds that staged in Delmarva (on the eastern seaboard of the U.S.) were the ones that bred around James Bay.

Recent studies have shown quite a different picture. In 2008, 2009 and 2010, several Whimbrels were fitted with satellite transmitters by researchers from CCB. One of these birds, named Hope, is the star of the project. She was given her Teflon harness and solar powered satellite transmitter in spring of 2009. She has completed two complete migrations and travelled, not to Hudson’s Bay as expected, but to the Mackenzie Delta in the Yukon.

Each winter, she has returned to the same wintering area at Great Pond, a Birdlife International Important Bird Area in St. Croix in the U.S. Virgin Islands. For the third consecutive spring, she has been found feeding at the same creek in Virginia, the same place where she was originally fitted with the transmitter.

This one bird has changed the accepted view of migration paths of Whimbrels. There is a substantial east-west direction to migration their migration paths, not just a north-south one.

Each place mentioned in the paragraphs above is vitally important to the survival of the species. Hope is not the only bird in the study and additional information about migration is being obtained from these other birds.

In addition to the satellite transmitters, some of the Whimbrels captured in Delmarva by the CCB team were fitted with radio transmitters. These require a receiver called a “datalogger” on the ground to record the passage of birds carrying the transmitters.

Since there are sight records of Whimbrel for the Lake Ontario shore, several of these were located here. One of these was financed by Willow Beach Field Naturalists and placed at Presqu’ile Provincial Park. Others were placed at Col. Sam Smith Park and Tommy Thompson Park in Toronto by the Toronto and Region Conservation Authority. In spring 2009, 10 of 30 tagged birds were detected at Col. Sam Smith Park.

None were detected in 2010, perhaps due to northeast winds during most of the spring migration period which pushed the migration path further west than usual.

Updated tracking maps and more information about this project can be found at http://www.ccb-wm.org/programs/migration/Whimbrel/whimbrel.htm

Let’s hope that this study can determine the cause of the Whimbrel’s decline before it is too late to reverse it.

May full of surprises

Nature Notes for May 13, 2011

In May, every day brings surprises. I open the door every morning to hear what last night has brought. One morning, I heard a Brown Thrasher, who sang vigorously for most of the day. One day, I looked out to find six male Rose-breasted Grosbeaks decorating my garden. These black and white birds with a splash of red at the throat are incredibly beautiful birds. They were accompanied by one much less colourful female.

After a rather cold and wet April, the first ten days of May finally had a few clear, dry days. This was much better for migrants and they have been moving steadily through.

One evening, a Blackburnian Warbler (black and white with a bright orange throat) was feeding on the multitude of midges in the yard.

My first Ruby-throated Hummingbird appeared on May 7, so I put out a feeder right away. I had reports of several others on earlier dates from different parts of Northumberland.

I have seen five of the six species of swallows that breed locally – Barn, Tree, Bank, Northern Rough-winged and Purple Martins. Cliff Swallows are probably around, but they are much less common and not easy to find. They also migrate somewhat later than the other swallow species.

Savannah Sparrows are singing their insect-like song from grassy fields. Field Sparrows are singing their bouncing song at the Alderville Black Oak Savanna (and many other places, too).  Vesper Sparrows can also be heard from field edges. These are all birds of fairly open country.

My first Scarlet Tanagers turned up also on May 7. In spring plumage, these birds are well-named – scarlet red with black wings.

Bobolinks could be found last week in the few fields where they still breed. They could also be detected passing overhead by their “pink” call. This species winters in South America, so have a long flight back north every spring.

The first flycatcher to return is usually the Eastern Phoebe. They have been back for a few weeks now, but last week they were joined by Eastern Kingbird, Least Flycatcher and Great-crested Flycatcher.

Yellow-rumped Warblers are still passing through. In addition to the Blackburnin Warbler mentioned above, they were joined by other warblers – Black-and-White Warbler, Black-throated Green Warbler, Palm Warbler, Magnolia Warbler, Yellow Warbler, Common Yellowthroat, Nashville Warbler, Ovenbird, Black-throated Blue Warbler, American Redstart and Northern Parula.

In a forest, a Winter Wren could be heard singing its long, melodious song. I always think that this song is much too big for such a small bird.

Baltimore Orioles and Orchard Orioles have both returned to serenade us with their sweet songs. These are also bright, beautiful birds. The Baltimore is orange with a black hood and wings. The Orchard is a brick red with black hood and wings.

Most of the birds mentioned in this column feed on insects. Those clouds of small midges which have been annoying us are a banquet for them. It is because of the northern summers’ abundance of insects that these birds make that long, dangerous migration every year.

Although we consider them “our” birds, they are only here for about four months of the year. They spend most of the year in Central and South America. Let’s enjoy their presence.