LANDER — Since Reed and Kathryn Rollins first discovered small rockcress, or Fremont rockcress, in 1981, the plant has spent most of its documented existence under the watch of government agencies worried about its future.
Recently the U.S. Fish and Wildlife Service recommended the plant as a candidate for protection under the Endangered Species Act.
Little is known about the plant native to Fremont County, said Genevieve Skora, a biologist with Fish and Wildlife. Scientists have performed few studies on it. It is unknown how long the plant existed before detection and recording, she said.
The small plant makes its home in the cracks and crevices of rocks, a tough environment with little vegetation, Skora said. It is found only in Fremont County near South Pass, she said.
Its low stature deters grazers from using it as food. Insects, moths and caterpillars do not use it as a preferential food, Skora said.
Since at least 1994, small rockcress has been a Bureau of Land Management “species of concern.” The agency fenced off the area where it grew, trying to remove any potential threats to the plant, Skora said. Yet the population continued to drop. The flowering population of the plant was 350 in 2010, down from a recorded high of about 900 in 2003, according to Fish and Wildlife.
No one is sure what’s causing the decline, although there is some speculation it could be drought-related, Skora said.
Fish and Wildlife studied the rockcress along with four other Wyoming plants — Gibbens’ beardtongue, precocious milkvetch, Ross’ bentgrass and Yellowstone sand verbena — for a year. At the end of the finding the organization decided the rockcress needed protection, but with limited funding for listing proposals, it is not a high priority, Skora said. Those plants that are deemed warranted of protection are given a priority ranking of 1 to 12, with 1 and 2 being high priorities. The rockcress received a ranking of 8.
Rankings are based on known threats to the plant, magnitude of the threat and the decline of the species.
Fish and Wildlife decided the other four plants recently evaluated didn’t need protection.
While the BLM listed the rockcress as a sensitive plant species, this is the first time Fish and Wildlife has recommended it for protection, Skora said. Candidate species such as the small rockcress don’t receive special statutory rules, but as a member of a list warranting protection, it’s acknowledged by state agencies that work is needed to help the species’ population numbers.
Numbers in the past two years for the small rockcress are on the rise, although the population is still small, said Bonnie Heidel, a botanist with the Wyoming Natural Diversity Database at the University of Wyoming. She has been involved in monitoring the plant.
With the plant recommended for protection, Heidel and other botanists will continue monitoring studies to try to figure out trends in the population and what affect its numbers.
The species also needs to be stored in a national seed bank, as a precaution in case the plant does become extinct, Heidel said.
“It’s a two-pronged approach,” she said. “We’re preparing for the worst and hoping for the best.”