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Henslows-Sparrow picture by Robert Rolley

Henslow’s Sparrow—How We Found this Elusive Bird on the Leopold-Pines Conservation Area

All photos in this article were taken by Robert Rolley (unless noted).

Henslow’s Sparrows are easily overlooked. They’re the bird equivalent of the very tiny mustard plant Leopold exalted in his essay “Draba” (see Leah Bieniak’s recent article) in his A Sand County Almanac. Just like Draba, Henslow’s Sparrows do almost next to nothing to get noticed. Size—they’re small; go figure, the size of a sparrow. Color—so nondescript that birding groups can deride them for a laugh as an LBJ (little brown jobber), and quickly move on before identification humility can sink in. Habit—Henslow’s spend a lot of time hunkered down in the thick thatch of prairies, preferring to walk when spooked, rather than fly. Population—the world’s population of Henslow’s breed in only a few states in the upper Midwest, so most birders would have to travel to see one. (I’m reminded that Margaret Atwood and Paul Ehrlich, when traveling through the area, had Henslow’s on their wish list.) Song—and, you’ll love this…Henslow’s have the simplest and shortest song of any bird in North America. It’s a little tze-lick, described as a weak, insect-like hiccup. Declines—steady losses of these secretive little birds haven’t made headlines like their boisterous brethren of the grasslands, the Eastern Meadowlark and Bobolink, but their decline has been no less real. They are listed as threatened in Wisconsin. Partners in Flight places them on the “Yellow Watch List” for species with declining populations, and identifies the loss of breeding habitat as the biggest threat to Henslow’s Sparrows.

A photograph of a Henslow's Sparrow taken by Robert Rolley.

A photograph of Henslow’s Sparrow taken by Robert Rolley.

We recently updated our land management plan for the Leopold-Pines Conservation Area (LPCA), the 4,000 acres of conservation land surrounding the historic Leopold Shack and Farm. Through the plan, our care of the land will help imperiled grassland and savanna bird species, and also pollinators, and ensure the land’s climate change readiness. According to our plan, our priority grassland bird species in need of help include Field Sparrow, Grasshopper Sparrow, Vesper Sparrow, Savannah Sparrow, Sedge Wren, Dickcissel, and, of course, Henslow’s Sparrow. Although all LBJs are of the grasslands, their specific habitat needs can vary greatly. For example, Vesper Sparrows only get the urge to nest if they can see some dirt between the prairie plants. Contrastingly, Henslow’s need a well-developed prairie thatch, achieved only through a lack of prescribed burning for 3 to 6 years. On the LPCA, while Henslow’s have been found over the years, previous monitoring methods were designed to cover very large tracts, so their habitat was only cursorily sampled. Now, our updated plan includes a methodology for ways to focus on them.

A photograph of a Field Sparrow taken by Robert Rolley.

A photograph of a Field Sparrow taken by Robert Rolley.

As part of our updated plan, we’re including a new bird monitoring protocol, which was redesigned over the last year by Sarah Woody, one of our Leopold Fellows. She consulted many specialists, including local bird experts; Mike Mossman, career ecologist and former Leopold Fellow; Dr. Stan Temple, a Senior Fellow at the foundation; and Mark Martin and Graham Steinhauer of Madison Audubon’s Goose Pond Sanctuary. We landed on a protocol that can be applied to any of our management units and designed for resampling over years. At each permanent point-count station, we observe birds for 10 minutes within a 25-meter (82 feet) radius. We note species, number, and importantly, breeding behavior, such as singing males, carrying nest materials, fledglings, etc.

We applied our new monitoring method to a roughly 80-acre area in which we have purposely allowed thatch to accumulate and, we hoped, improve the habitat for Henslow’s. Our first sampling day was early morning and mid-week. There are six randomly assigned point-count stations. Within our point counts, we heard Eastern Meadowlark, Field Sparrow, and loads of Clay-colored Sparrows, which incidentally, also require thatch to nest. At just one point-count station we heard Henslow’s Sparrow; it so happened to be at the farthest point from the noise of the nearby highway interstate. We recalled Mike Mossman’s pro-tip that point-count locations near the interstate should be sampled on Sundays when traffic is the lightest. A few days later, on a Sunday, we heard Henslow’s Sparrows at 5 of the 6 point-count stations, with two singing males at a couple of points! They are indeed light callers and decidedly secretive. Up until this point, while we knew unmistakably we’d heard their call (Merlin ID confirmed!) we weren’t sure we had even seen one. We wanted a picture.

A photograph of Robert Rolley in the field.

A photograph of Robert Rolley in the field.

We contacted Robert Rolley, one of the foundation’s volunteers and whose photography has been part of our phenology calendars and program promotions for years. Robert, and his wife Karen Mesmer who is a Good Oak Society Member (find out how you can join below!), are usually “glassing” the big birds—Sandhill Cranes. But, Robert was up for the challenge. To hear a bird just twenty-five feet away and not see it—for 45 minutes—is frustrating to say the least. We had the idea to play a few Henslow’s calls on our phone to spark its curiosity. Success! Within a few minutes, it lit on a shrub near us. Robert got a number of shots, but had to reposition for a less obstructed view. After a minute, the bird flew back to the other side of us, just barely visible above the thatch. A moment later, it hopped up and landed on a stalk of grass. Robert snapped two dozen photos in what felt like two seconds, and then the bird was gone. Robert said triumphantly, “We got your Henslow’s!” After a high-five and a few good laughs replaying the scene, we headed to the car. We left delighted that this LBJ was going to get proper credit, just as Leopold writes of Draba, “…just a small creature that does a small job quickly and well.”

Photograph of Henslow's Sparrow taken by Robert Rolley.

A photograph of Henslow’s Sparrow taken by Robert Rolley.

Acknowledgements:  Our land care for all the plants and animals—great and small—within the Leopold-Pines Conservation Area, is only possible through the generous support of the Pines Family and Don and Jeanne Cahoon, and conservation partnerships with the Natural Resources Conservation Service and United States Fish and Wildlife Service-Partners for Fish and Wildlife Program. Thank you!

Read more about the Leopold-Pines Conservation Area here.

Become a member of the Good Oak Society.

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