2025 Spring Morning Flight

Written by BSBO Morning Flight Counter, Gautam Apte

Join Gautam for a Birds at Home presentation HERE.

From the first day of March through the last day of May this year, it was an excellent season to count birds as part of BSBO’s first full-season morning flight count at Metzger Marsh Wildlife. Thanks to the support of our regional partners, we were able to have a very successful first season of counting, and we’re looking forward to continuing our efforts in the field of visible migration monitoring!

It's long been known that the marshes of northwest Ohio are a critical area for migratory birds, but most research aiming to describe the importance of the region has focused on birds in the stopover phase of their migratory journey - those that are in the process of resting and refueling in between migratory flights. The mission of our morning flight count is to shine some light on these less-studied flights, as we attempt to survey birds in active visible migration. By observing and documenting birds that are undertaking migratory flight, we have the capability to collect data on a spectacular diversity of birds as they move over the region from a single site. This ability to sample a host of species that, on the ground, use largely different habitats, makes visible migration monitoring a highly efficient method to gain a better understanding of migration through northwest Ohio. As migration is the period with the highest mortality rate for the overwhelming majority of North American species, better understanding the dynamics of migration is crucial to help protect birds in this most vulnerable phase of their annual cycle, and we’re happy to report that we’re already learning more about some of our regular migrants after just one season of counting. 

The early days of the count were often long and bitterly cold, but occasional warm and sunny March skies along with southerly winds brought staggering numbers and diversity of birds, with tens of thousands of individuals passing over on the most active days. From the early March days featuring streams of diving ducks and swarms of blackbirds, the weather softened into April as hordes of Bonaparte’s Gulls and high kettles of hawks became the staples of the count. By May, the dawn hours were filled with the soft chip calls of warblers, orioles, and other songbirds passing over in morning flight before squadrons of Blue Jays would appear high overhead as the warmth of the day set in. In what felt like no time at all, migration had passed its peak, and the last Arctic-breeding shorebirds turned the last page of the count, drawing to a close after three action-packed months.

In our first season at Metzger Marsh, we recorded a total of 660,796 birds across 203 species. These numbers represent only birds observed in active migration. 27 additional species of birds were seen or heard at the site but not recorded as part of the count as they weren’t observed actively migrating. This total of 230 species for the spring is one of the highest single-site lists for all of Ohio this year, emphasizing that we are extraordinarily fortunate to have a hotspot like this right here in northwest Ohio! In addition to bird species, we made note of non-avian migratory taxa at the site and incidentally recorded 9 species of insects in active migratory flight. Our counter Gautam spent at least 6 hours surveying migration on 83 days this spring, and in total he recorded 526 observation hours from his watchpoint along the outer dike. 

Over the course of the season, we welcomed 1,421 visitors to the morning flight count, a number far greater than we expected at the beginning of the season! The interest displayed in this brand-new effort was incredible, and it was a privilege to be able to share our research with folks from around the world right there in the field. We hope to soon have more information on our findings from the count available, and to be back in the field counting birds! 

The highlights for the count were many and frequent, and a few of these are shared below.
​(All images by Gautam Atpe)

Lapland Longspur

• Lapland Longspurs are a regularly occurring wintering species in Ohio, but rarely seen in large numbers. As they spread out through corn stubble and other open areas in winter, they’re rarely seen in concentrations greater than a few hundred at a time. The season total of 12,396 longspurs passing over Metzger Marsh is at least an order of magnitude greater than any other migration count site in North America, and the daily maximum of 9,087 represents a record high count for Ohio. ​

Rusty Blackbird

• The swampy woods of northwest Ohio are well known as an important stopover site for the rapidly declining Rusty Blackbird, but it has been previously difficult to quantify their passage through the region as a result of their prolonged stopover period. We observed migrating Rusty Blackbirds on 42 days this season, totaling 10,962 individuals. This total represents a significantly higher proportion of the population than previously recorded by any survey method and is an excellent example of the value of visible migration monitoring in the context of species conservation. 

Bald Eagle

• While the Metzger Marsh site is not ideally suited for all species of raptors and soaring birds, we still saw large flights of raptors on days of favorable conditions. Northern Harriers, Bald Eagles, and American Kestrels are not as sensitive to shorelines and water bodies as other soaring raptors, and we saw good numbers of these species. The daily maximum of 119 Bald Eagles is likely one of the highest counts recorded in Ohio. 

Lesser Yellowlegs

• One of the less expected features of this initial monitoring season was the strength of shorebird passage over the site. Northwest Ohio is well known as a site for shorebird stopover, but very few migration count sites record large numbers or diversity of shorebird species in active passage, regardless of proximity to stopover sites. Significant season totals included 277 American Golden-Plovers, 1,277 Killdeers, 698 Lesser Yellowlegs, 119 Sanderlings, 1,926 Dunlins, and 1,838 Pectoral Sandpipers.

Blue Jay

• The Great Lakes are well known also as a significant site for Blue Jay migration, which remains poorly understood and understudied. We observed 63,620 Blue Jays passing over the site this spring and noted strong associations with climatic variables which enable the potential for further study into the behavioral mechanisms of this strictly diurnal migrant.

Blackpoll Warbler

• Neotropical passerines are the best-known feature of spring migration in the region, but also some of the most poorly understood species in the context of migratory behavior. It has long been known that long-distance nocturnal migrants frequently engage in redirected dawn migration, or “morning flight”, but the mechanisms behind this behavior remain a mystery. Studies along the eastern seaboard and even some in the Great Lakes have attempted to piece together the puzzle but to date, the function or significance of this type of migration is not completely defined. We hope our large and carefully collected dataset will be a useful resource as we work with other organizations and researchers to investigate the drivers of this redetermined morning flight. 

Eurasian Tree Sparrow

• We were able to observe quite a few rare or unusual birds this season! Two Golden Eagles were an excellent sighting in the early season, and two Red-throated Loons were exciting finds in mid-April. The rarest bird of the season came in late May, with a Eurasian Tree Sparrow passing over, only the third record for Ohio! A Eurasian Collared-Dove a few days later was also an exciting find. Throughout the season, species like Ross’s Goose, White-winged Scoter, Whimbrel, and Glossy Ibis were also unexpected and thrilling to observe in active migration.

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This project would not have been possible without our partners at Ohio Division of Wildlife, Winous Point Marsh Conservancy, Kowa Sporting Optics, Trektellen.org, and our generous donors. Please visit bsbo.org to learn more about our mission and the morning flight project. ​