Before a thief could hatch a plot to take any more eggs from a mallard nesting near the McPherson Square Metro station, the target of the thefts flew the coop.

After being plagued by a thief, apparently human, who repeatedly took eggs from her nest, the duck saw two of her three remaining eggs hatch on Monday morning. She quickly ushered them away from the planter on I Street NW where she had sat with them for nearly a month.

During that incubation period, the eggs in her nest dwindled from at least nine to just three. Staff and volunteers at City Wildlife — an organization that keeps tabs on ducks as well as other animals who try to make it in the downtown D.C. rat race — believed that someone was grabbing the eggs, perhaps to eat them as the Asian delicacy balut, made of almost-developed fertilized eggs. A security guard even spotted a man approaching the nest wearing gloves.

City Wildlife reported the theft of the eggs to the U.S. Fish and Wildlife Service, saying that tampering with a migratory bird’s nest is a federal crime.

But on Monday morning, the nest monitors met the disappearance of two more eggs with pleasure, not consternation. This time, those eggs had turned into baby ducks.

The mallard sits on her remaining eggs on Sunday. (Julie Zauzmer/The Washington Post)

Anne Lewis, the president of City Wildlife, and an employee at the building at 1575 I Street NW where the duck had made her sidewalk home both said that multiple passersby reported seeing the mother duck with her two ducklings about 8 a.m. Monday.

One egg did not hatch and remained in the abandoned nest as of 11:30 a.m.

“This is truly great news, as it means she is now off with her ducklings in search of her water source — and most likely her mate who may be waiting there for her,” Lewis wrote in an e-mail.

She noted that the journey to one of the several water sources in a few-block radius — including fountains and ponds at the White House, on the Mall, at Lafayette Square and Constitution Gardens — would not be without its own perils. Gaping storm drains, swooping crows and speeding cars can all endanger little ducks. (See Robert McCloskey’s picture book “Make Way for Ducklings” for the definitive text on that subject.)

But Lewis said she hoped the mama duck and her two hatchlings were safe and splashing by now.

She wrote, “It is our expectation that she is happily swimming with her new family in one of DC’s many pools, rivers, or creeks — and very glad to be away from the egg-robber!”