With the passing of peak fall warbler migration comes yet another exciting time — fall sparrow migration.
Many of Iowa’s sparrow species are transient, wintering south of our state. Therefore, the fall offers one last chance to see many sparrow species that will not return until the following spring.
Sparrow diversity should peak in early October, eventually tapering out in November. More than 20 species of sparrows and their relatives can be found during fall migration. Generally, sparrow identification of adults is pretty straightforward. Juveniles of closely related species, however, can be very tricky.
Iowa is unique among most other states in that it sits squarely in the migration path for two of our most beautiful and sought after fall sparrow species. These are Nelson’s and LeConte’s. Nelson’s sparrow is adapted to both coastal salt marsh habitat and inland freshwater marshes. LeConte’s can be found in wet grasslands, but also can be seen around sedge marshes.
Hawkeye Wildlife Management Area in Johnson County, offering a gamut of different bird habitat, is an ideal place to find both of these sparrows during fall migration. Many times both can be found in relatively close proximity if habitat is correct. In Linn County, varied grassland habitat north and south of Morris Hills Road, encompassing both Wickiup Hill Learning Area and Chain-O-Lakes WMA, is another good spot to look.
So what makes these species so visually aesthetic? Gold. Nelson’s and LeConte’s sparrow have golden hues in the face, breast and flanks. One major difference is in the nape (back of the neck). Nelson’s nape is gray, whereas LeConte’s has lines of purplish spots. LeConte’s has a white crown stripe, which is a white stripe running down the middle of the top of its head.
Identification of these sparrows can be, admittedly, tough because many times they are often hard to locate. LeConte’s, for instance, will pop up out of grasses and quickly flutter away and land out of sight. If you can get a solid look at the head of either sparrow, from various angles, a confident ID can be made in the field.
OTHER BIRDS TO LOOK FOR IN OCTOBER
Rails, such as Sora and Virginia rail, may persist in swampy habitat. The elusive yellow rail prefers short, grassy habitat near the edge of wet areas. Be careful not to mistake juvenile Sora for yellow rail. Each can have a white trailing edge to the flight feathers. Yellow rail’s white should be centered more toward the inner half of the wing.
Sparrow diversity will reach its peak. Look for roads with shrub-like habitat and also large woodpiles.
Warblers that have a later migration window, such as orange-crowned and yellow-rumped, can be expected.
Bobolink can persist into October. Be careful not to mistake immature/female bobolink for Nelson’s sparrow.
Several species of hawks continue to migrate well into October.
Sedge and marsh wren can often be found while looking for LeConte’s and Nelson’s, respectively.
Oct 3, 8 a.m. — Kent Park Bird Walk. Meet at the Conservation Education Center.
Oct 6, 7 a.m. — Hawkeye Wildlife Management Area for sparrows and other fall migrants. Meet leader Brandon Caswell at the parking lot on Swan Lake Road between 6:45 and 7 a.m., across from Swan Lake. We will carpool our way around the area with moderate hiking at some viewing areas. Dress for wet/muddy trails and bring a spotting scope if you have one. We’ll finish up around noon.
Oct 17, 8 a.m. — Kent Park Bird Walk. Meet at the Conservation Education Center.
Oct 18, 7 p.m. — Meeting. Doug Harr, birder, photographer, and president of Iowa Audubon, will present “Birding the Rio Grande Valley & Texas Coast.”
Oct 21, 7:30 a.m. — Belgum Grove and Riverside Trail for sparrows and other fall migrants. Meet leader Fawn Bowden at the Fin & Feather parking lot at 125 Highway 1 West in Iowa City for a morning of birding at two hot spots new to the club. We’ll carpool to both locations and hike the mowed paths at Belgum Grove and a gravel trail at Riverside.