First-time research is underway in Cameron County to understand the origins of rare coastal Lomas. But one researcher has concerns land development will outpace his project.

The Lomas are mounds of clay, scattered on the coastal tidal flats. Their vegetation supports a small ecosystem. And those unique features are found nowhere else in North America, according to UTRGV geologist Dr. Juan Gonzalez. 

He and others are putting a small seed grant to work to find out when the rare Lomas were formed.

"Very unique for any delta," he said at his office, showing the map of an area he and a small team are working along Highway 48, south of Port Isabel.

The Loma at that location was cut down the middle to make way for the highway. Gonzalez said the results of a recent radiocarbon dating found it to be 4 thousand years old, compared to the delta's age, approximated to be 8 thousand years old.

Gonzalez says the recent dating didn't quite reach the base of the Loma, which is likely older. A second sample was sent for dating this week, he said.

The Lomas are formed by the accumulation of clay clumps, aided by small holes dug by coastal crabs, he explained. The clay accumulated over time, allowing for vegetation to form. Those formations stand apart from the coastal flats where they sit.

Gonzalez worries the pace of development in some coastal areas will mean the loss of many Lomas. Along Highway 48, land to the west is protected by the U.S. Fish and Wildlife Service. To the east, the land is owned by the Port of Brownsville.

Late last year, Rio Grande LNG broke ground on a more than 900 acre terminal site at the Port. The company bulldozed a large portion of the land and is preparing it for future development.

Since then, Port commissioners directed staff to preserve Lomas that remain on the Port's property.

"Road construction, port expansion, LNG, SpaceX — every time I drive by I see new deterioration," Gonzalez said.

There's also evidence the Lomas were used by prehistoric peoples who lived in the Valley. Over the years, collectors have recovered fragments of shell, stone tools and pottery on the mounds, said Dr. Edward Gonzalez-Tennant, professor of anthropology at UTRGV.

"Circa 1,200 to 1,000 years ago, they would have been very active places for prehistoric inhabitants in that area,” he said.