As recently as the year 2000, seabeach amaranth was considered "lost" from the list of New Jersey flora.

But ever since the state endangered and federally threatened plant was rediscovered following a beach-fill project in Monmouth County, it's made quite a comeback.

Nearly 7,200 of these low-growing plants were spotted by biologists along New Jersey's coastal beaches south of Sandy Hook during a 2019 plant census. That's more than six times the 2018 total of 1,053 plants, the state Department of Environmental Protection announced this week.

"Our DEP biologists indicate that while the increase can be the result of many different factors, it could not have occurred without the presence and structural integrity of the habitat required by this species," said DEP Commissioner Catherine McCabe.

It's an annual plant, meaning the plants counted during one year are new plants resulting from seed dispersed in prior years. On an undisturbed beach, DEP said, seabeach amaranth may grow anywhere from the base of the dune to the high tide line.

"We saw a tremendous increase from 2018 to 2019 — that doesn't necessarily mean we're going to see that kind of increase, or even an increase, in 2020," said DEP spokesperson Caryn Shinske.

Shinske said seabeach amaranth is one of only six plants in New Jersey considered either endangered or threatened by the U.S. Fish and Wildlife Service.

Special protection zones known as plant protection strips are in place at Island Beach State Park, to shield rare plant species like seabeach amaranth from the public. Experts spotted 1,591 seabeach amaranth plants at the state park in 2019, compared with 307 last year.

The plant with spinach-like leaves and reddish stems had not been observed in the state from 1913 to 2000. It was spotted again in 2000 near Sandy Hook following a project to beef up coastal storm protection.

Grants from the federal government pay for annual surveys of the plant in New Jersey since its rediscovery.

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Contact reporter Dino Flammia at dino.flammia@townsquaremedia.com.