CAPE ELIZABETH — Volunteers had an arboretum in mind as they cleared invasive plants from part of Fort Williams Park last fall.

Little did they realize that their hard work would uncover evidence that the thick mass of plants was habitat for the endangered New England cottontail rabbit.

After someone told it about the clearing, the state Department of Inland Fisheries and Wildlife visited the site and found rabbit droppings. DNA analysis confirmed that the pellets were those of the New England cottontail.

The rabbit was placed on Maine’s list of threatened and endangered species in 2007 and is a candidate for protection under the federal Endangered Species Act.

Officials from the town and the state are now discussing what to do in response to the unintentional destruction of cottontail habitat. The town has agreed to pay as much as $4,800 for capturing the rabbits in the park and taking them to a suitable location elsewhere in Maine, and for equipment to monitor that site.

Town Manager Michael McGovern said the Department of Inland Fisheries and Wildlife also has asked the town to set aside land elsewhere in Cape Elizabeth and manage it as habitat for New England cottontail rabbits, to make up for what was lost in the park.

McGovern said the department asked for eight times the area that was destroyed. It estimates the cleared area covers 2.5 acres, but McGovern says it’s less.

It’s unclear still how much land will be set aside. But more importantly, McGovern said, it’s unfair to require the mitigation because the town did not know the area was habitat.

“The larger issue is, do we deal with this matter going forward, or do they penalize us for something that we had absolutely no knowledge of?” he said. “The town is willing to work with them moving forward.”

Judy Camuso, a regional biologist with the Department of Inland Fisheries and Wildlife, said the town was unaware of the habitat. As far as she knows, it didn’t need a permit from the state to clear the plants. Normally, a review is triggered when a landowner seeks a building permit.

“The reality is,” she said, “we’re still losing habitat for an endangered species.”

She said the state requires so much land to compensate for lost habitat because it takes time for land to become fully suitable for the rabbits.

It’s not known how many New England cottontails — not to be confused with other species of cottontail rabbits — are in Maine. The rough estimate of the winter population is 300. The number would be higher after the breeding season.

No one knows how many New England cottontails may have used the area that was cleared at Fort Williams Park. Camuso said it was probably a “handful.”

The area that was cleared for the first part of the arboretum is near the Cliff Walk Trail, which connects Ship Cove to Portland Head Light.

The area stands in stark contrast to the nearby grassy spots and uncleared areas that are choked with tall brush. Trees dot the cleared brown expanse, which is empty aside from short stumps and twigs.

New England cottontails need places that provide dense cover, such as shrub thickets and young forests that are regenerating from disturbances.

Camuso said that while the rabbits are particular about their habitat, they aren’t fussy about whether the vegetation is native or invasive.

The Arboretum at Fort Williams, a privately funded effort, aims to create 15 planting sites in the park. The removal of exotic invasive species is a key part of the project. Invasives like Norway maple, Asian bittersweet, multiflora rose, Japanese barberry and autumn olive crowd out native species.

McGovern said any further clearing is on hold until the town works out an agreement with the state. Camuso said it isn’t clear how much of the 90-acre park may be habitat for the rabbits, since much of the property consists of open areas, lawns and forest.

The head of the arboretum effort, Kathryn Bacastow, could not be reached for comment.

Staff Writer Ann S. Kim can be contacted at 791-6383 or at:

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