A bobolink in a field at the Hart Farm in Holden. Credit: Courtesy of Jane Rosinski

This time of year, two familiar sounds seem to signal the arrival of summer.

One is the reassuring thrum of a tractor’s engine as farmers mow their sweet-smelling hayfields. The other is the bubbling, lyrical song of the bobolink, a small grassland bird with a shrinking population that is known for its cheerful plumage and captivating voice.

But put them too close together, and the bobolink and the tractor sound more like disaster. Just ask scores of ardent bird lovers who have registered their dismay that a farmer last weekend mowed large open fields at the Hart Farm in Holden, a historical dairy farm that was purchased last year by the Holden Land Trust.

Bobolinks are known to nest there, and a few of the birders had asked land trust officials if the mowing could be delayed so the chicks would have a better chance of survival. But the farmer leasing the land needed to make sure that the hay he cut had sufficient nutrients to feed his herd of dairy cows and couldn’t wait, according to Betty Jamison, a board member of the land trust.

“We did not go out to kill off the bobolinks — it’s just a hard balance,” she said this week. “The farmer knew the bobolinks were an issue, but there’s not much you can do about it. These have been hayed fields for years. There are other wildlife that can be damaged in mowing a field. It’s a balancing act between trying to keep habitats and to preserve farming in this area.”

But for avid birders such as Jane Rosinski, that’s not good enough. Rosinski, who has worked as a naturalist and educator for the Maine Audubon Society and who also served on the board of the land trust until she resigned that post about two years ago, lives close to the farm.

She had been enjoying the sounds of the bobolinks she has heard nesting in the fields, but when she went by last Saturday night and saw the fields had been mowed, she was worried. The next day, her concerns proved to be correct.

“I went back up on Sunday morning, bright and early, and found a horrible mess,” she said, the tears audible in her voice. “I did look for little bodies. I didn’t find any. I did find many upset adult bobolinks. It was awful.”

A species in decline

Between 1966 and 2015, bobolinks in Maine declined nearly 3 percent each year, but in the last decade, the rate of decline has been increasing, according to Agricultural Allies, a Somerset County-based program that tries to support both grassland birds and local farms.

“In addition to being a delight to see and hear, bobolinks and other grassland birds are true agricultural allies to central Maine farmers as these birds consume large quantities of both insect and weed pests each growing season,” the Agricultural Allies website states. “Unfortunately, the population of these and other birds is in a continuing steady and sharp decline … habitat loss is the main reason for these declines. In addition, early and mid-season cutting of agricultural grasslands has catastrophic impacts on nesting success of birds using these habitats.”

Mowing hayfields during the nesting period results in total nestling failure, according to the project, which works with interested farmers and landowners to provide safe habitat for grassland bird nesting. It also provides incentive funds for some farmers who will delay mowing their fields for the 65-day period needed for bobolinks and other birds to raise their young.

“I’m all for farmers, too. I don’t have a problem with them mowing the field. We just asked for a delay in the mowing,” Rosinski said. “Many farmers consider bobolinks to be a positive influence. To see them get chopped up is hard to take.”

She had asked the board members of the land trust if they could wait until July 15 to have the fields mowed. That would likely be enough time for the migrating bobolinks, who made it to Maine in the first half of July, to nest successfully before they start their 6,000-mile return trip to South America. It’s important because bobolinks are “incredibly interesting birds,” she said, and they’re under pressure. That’s why she posted some photos of the mowed field and a video of agitated-seeming adult bobolinks to the Maine Birds Facebook group, which has thousands of members.

“I was so upset — I was just looking to get other people as enraged as I was,” she said.

She succeeded. Lots of those bird fans quickly registered their unhappiness with the Holden Land Trust, leaving scathing one-star reviews on the nonprofit’s own Facebook page.

“Will never visit or donate to again,” one birder posted.

“Holden Land Trust is destroying nesting bobolink habitat despite being asked to wait til babies fledge,” wrote another. “Despicable.”

A tough balance

But balancing the needs of farmers and birds is not a cut-and-dried scenario, according to farm experts. Rick Kersbergen, a University of Maine Cooperative Extension professor of sustainable dairy and foraging systems, said that the timing of their first cutting of hay is very important to dairy farmers. The longer they wait, the less protein remains in the hay, and that matters to their milking cows.

“f you’re trying to feed a milking cow, you need the best nutrition you can give them,” he said. “It really is critical for farmers to get that first cutting.”

And Jamison said that not everyone may be familiar with the status of the Hart Farm, which has a “Forever Farm” easement and may be the last working farm in Holden.

“The land trust is about more than bobolinks, and the Hart Farm is about more than bobolinks. It’s about more than a bird sanctuary,” she said. “We’re looking at all types of wildlife, but we’re also looking at preserving agriculture in Maine.”

She believes that the farm had been “under prime threat” from development, and keeping it in agriculture is better for birds and other wildlife than seeing the land turned into housing developments.

“This whole controversy, it’s like single-minded tunnel vision,” she said. “It’s a working farm. We’re trying to balance all the things. We’re not changing what we’re doing, because preserving open spaces and promoting agriculture has been part of our goal from the beginning.”

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