Life in Maine was pretty good for bobolinks in the 1700s and 1800s. Much of southern Maine had been converted to farmlands and the hay fields that farmers maintained to feed their livestock were just the ticket for this grassland bird.

But since the turn of the 20th century, many farms in Maine have reverted to forest. I am sure you have encountered the remnants of stone or wire fences as you walk through a patch of forest now. Over 90% of Maine is now forested, the highest percentage of any state. That statement includes sparsely populated Alaska because much of northern Alaska is treeless tundra.

Natural grasslands in Maine have always been fairly limited in extent. The Kennebunk Plains, maintained by The Nature Conservancy, is the best known of our remaining tracts of native grassland.

These grasslands are home to a suite of species including upland sandpiper, grasshopper sparrow, Savannah sparrow, vesper sparrow and bobolink. Unfortunately, all these species are in serious decline. These declines are not occurring only in Maine. The State of the Birds 2022 project found that 10 of the 15 grassland birds across North America are showing significant declines. Five of these are classified as “Tipping Point” species. Since 1970, these species are showing accelerated population declines. In other words, the rate of decline is becoming higher every year. That pattern is a recipe for extinction, hence the notion that these birds are at a tipping point.

The State of the Birds 2022 researchers found that grassland birds have collectively declined by 34% since 1970, the most severe decrease of any other group of birds. Other groups in trouble are shorebirds (33% decline), sea ducks (30%) decline and eastern forest birds (27%) over the same time period. There was good news for waterbirds (18% increase) and ducks (34% increase).

The reasons for the declines of grassland birds are manifold. Over 60% of native grasslands in the country have been lost over the years to agricultural development and the encroachment of abutting forests. Native grasslands close to agricultural fields can be affected by pesticide application on the farms.

Hay fields provide alternative nesting habitat for grassland birds. Alas, there is a tension between farmers and birders because farmers need to cut their fields during the bird nesting season.

Farmers need to cut their hay when the grasses are at their highest nutritive value. In Maine, that critical date is around the end of June into early July. Unfortunately, grassland birds nesting in these fields may not have finished nesting by then.

In an ideal world, farmers would wait until at least July 15 to cut their fields. However, farmers maintain their high fields to maximize the production of high-quality hay, and, in my view, it is not fair to farmers to go beyond simply politely asking them to delay haying. If the farmer refuses, so be it. After all, we all depend on the milk and beef from cows and the wool from sheep that benefit from a productive hay harvest.

I fully support the work of Ag Allies in Maine. They pay farmers to delay their harvest but many farmers are reluctant to accept cash in exchange for an inferior hay crop.

There is one recommendation we can make to farmers as they cut their fields: cut from the inside out. By cutting from the outside in, the way most of us mow our lawns, nestling and recently fledged birds are herded to the center of the field. As the last of the field is cut, the birds are caught in the center of the field and are easy pickings for predators. Cutting from the inside out, pushes the birds toward adjacent forest or shrubs, reducing predation risk.

A more effective way to try to stem the decline of grassland birds is to acquire tracts of open land like abandoned fields and brushy areas and manage them for grass growth. Such grasslands will likely need to be mowed or burned periodically to prevent succession of the field to forest. Without the need to produce high-quality hay, the mowing or burning can be done well past the nesting season.

Herb Wilson taught ornithology and other biology courses at Colby College. He welcomes reader comments and questions at whwilson@colby.edu

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