Warbler Watch: They’re Migrating Again

In the middle of August I begin to anticipate the birds migrating southward who will begin showing up in Eliza Howell Park before the end of the month. I am thinking, at this particular time, of one species (Common Nighthawk) and a whole bird family (Warblers). I hope to comment more on Nighthawks in another post. This is about the warbler migration. Many warblers are now leaving the North Woods and heading our way.

Invitation: Detroit Audubon is sponsoring a bird walk at Eliza Howell Park on Saturday, September 8, starting at 8:00 a.m. The event is open to anyone interested and there is no cost.

Of the 20 or so warbler species that pass through the park on their way south each year (most from late August to late September), a select few are pictured here with a range/migration map for each. The yellow section on the map is the breeding range, the purple is the winter range, and the pink indicates the areas over which they migrate.

Canada Warbler

Canada Warbler Migration

All the warbler photos in this essay were taken by Margaret Weber.

The maps are from Tom Stephenson and Scott Whittle, The Warbler Guide, 2013.

Most warblers are long-distance migrants that spend much less time in their North Woods breeding habitat than on the wintering ground and in migration. It was only a short time ago, in May, when they last passed through here, as they headed north. Since then, they have built nests, incubated eggs, fed their young, and are now heading back to locations where insects can be found throughout the winter months.

Magnolia Warbler

Magnolia Warbler Migration

When we last saw migrating warblers in Detroit in May, they were in their bright breeding plumage, as represented in these pictures. Now many of them will be arriving in a somewhat different and somewhat duller fall/winter look. The process of learning to identify warblers involves learning the visual variations from spring to fall, a sometimes challenging project that may take a few years. Fortunately, the Fall migration is spread over more weeks than the brief intense Spring migration so there is a little more time to develop field skills.

Chestnut-sided Warbler

Chestnut-sided Warbler Migration

Annual bird migration is a fascinating natural phenomenon. Warblers are very small birds. Chestnut-sided Warblers, for example, are 4 – 5 inches in length and weigh about 0.4 oz. Most of the tiny warblers migrate a couple thousand miles twice each year. It is hard to imagine the energy required, but easy to understand the fuel stops along the way. Since many small birds migrate at night, early morning, as soon as it is warm enough for insect activity, is often a good time to see them as they begin to feed.

Blackburnian Warbler

Blackburian Warbler Migration

I don’t expect to see every migrating warbler species every Fall in EHP; their stops are brief and not always in the same location. Good bird observations often result from being “in the right place at the right time” and the right place and time cannot always be predicted with full accuracy. Based on past experiences and years of records, however, I can quite confidently predict that Blackburians will be visible and that they will be among the warblers seen before the end of August. Some of them do not have far to fly from their breeding ground to Detroit.

Wilson’s Warbler

Wilson’s Warbler Migration

As can be noted from the maps above, many warblers that are seen in eastern United States are not found in western states. Wilson’s warbler is an exception. It migrates through/over almost every state.

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There is a saying common among social justice advocates and environmentalists: “Think globally, act locally.” The big picture provides the context and, at times, the incentive for effective and significant local projects and behavior.

In a somewhat similar way, local nature observation and appreciation can be even more enriching and satisfying with an awareness of the big picture. When I see warblers stopping in the park on their way south over the next several weeks, I am thrilled just to see them but also impressed and amazed at where they have been and where they are going.

 

Warbler Time at Eliza Howell: Neotropical Migrants

A neotropical migratory bird is a bird that breeds in Canada and/or the U.S. and spends (our) winter in Mexico, Central America, South America, or the Caribbean. Many such species arrive in and/or pass through SE Michigan in May.

Over 2 dozen different species of warblers alone arrive at this time of the year and many, many bird watchers head for migrating warbling hotspots like Magee Marsh in Ohio, Point Pelee in Ontario, and Tawas Point in Michigan.

Warbler chasers come to these hotspots from all over, in big numbers, and with big cameras. These tiny birds (about the size of chickadees) are one of the key reasons that bird tourism is a big business in some locations.

Warblers also pass through Eliza Howell Park, though in smaller numbers. Here are some of the migrating warblers that I tend to see every May in the park. Each picture is of a male in breeding season plumage.

The following photos were all taken by Margaret Weber. My thanks for the permission to use and my appreciation of the quality of the shots.

Blackburnian Warbler

Blackburnians pass through here on their way to their breeding grounds from mid-Michigan through much of Canada.

 

Black and White Warbler

This is one of the few warblers that forages for insects along the branches of trees rather than in the leaves.

 

Chestnut-sided Warbler

Chestnut-sided Warblers glean insects from the bottom of leaves. Their breeding area includes much of Michigan.

 

Northern Parula

In breeding season, this forest bird is usually high in the canopy. In migration, however, it is often low enough for good looks.

 

Nashville Warbler

The Nashville Warbler is misnamed. It migrates through Tennessee, but neither summers nor winters there. It breeds in northern Michigan and Canada, nesting on the ground.

 

Magnolia Warbler

The Magnolia Warbler was given its name 200 years ago by an ornithologist who found it in a magnolia tree in Mississippi (in migration). It breeds in the northern forest, far from any magnolias.

 

American Redstart

American redstarts breed in much of the eastern United States, favoring woodlands with abundant shrubs. I have not yet observed them in breeding season in Eliza Howell Park, but it would not surprise me if I do some year.

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There is not much that can compare with the excitement of seeking and finding these beautiful birds as they near the end of their long migration northward. During their May migration through this part of the country, approximately May 5 to May 20, I spend some time with the crowds at the famous hotspots.

That is exciting, but it is even more satisfying for me to see these warblers right here in this Detroit park. I hope to introduce others to the experience.