Sponsored by


New 'endangered' finding for native plant could hamper Rosemont Mine

Rare Bartram's stonecrop would be threatened by copper mine's use of water, enviros say

A "striking" succulent is one of several rare species that may yet derail plans for the Rosemont copper mine after the U.S. Fish and Wildlife Service said Monday that the plant should receive protection under the Endangered Species Act.

Known as Bartram's stonecrop, the blue-green succulent typically lives on rocky outcrops in narrow canyons, and historically, the plant was found across the sky island mountain rages in Southern Arizona and northern Mexico. However, currently only 4,628 adult plants are known to exist in the United States, with about 50 specific sites covering just 17 acres, prompting Fish and Wildlife, a part of the U.S. Interior Department, to declare the plant threatened. 

The inclusion of Bartram's stonecrop on the endangered species list may create a new roadblock for plans to carve an open-pit mine in the Santa Rita Mountains about 30 miles southeast of Tucson.

The plant is one of more than a dozen imperiled animals and plants threatened by the proposed mine near Tucson, which would affect more than 145,000 acres of wildlife habitat, said the Center for Biological Diversity, which has been attempting to stop the mine since its inception.

Prompted by the legal action from the Tucson-based Center for Biological Diversity, the federal agency ruled that the loss of available water from mining operations because of the proposed—and highly controversial Rosemont mine—could harm Bartram's stonecrop. The plant was first identified as a candidate for the endangered list in 1980, however the plant remained unprotected by 2010, when the Center petitioned to have it added. In 2019, Fish and Wildlife said it would consider protecting the plant, and in 2020, the environmental group sued the Trump administration, arguing that Bartram's stonecrop was one of 241 plants and animals that must be protected.

While the agency said that there weren't individual plants in the Rosemont Mine's footprint, there are succulents that could be harmed by "dewatering" of streams that could lead to a loss of trees and other shade canopy, as well as reductions in spring and stream flow and humidity in nearby Bartram's stonecrop populations.

The open-pit mine mine would directly affect more than 950 acres of land, and the company plans to dump around 1.9 billion tons of waste rock on nearly 2,500 acres of land in the Coronado National Forest, part of Southern Arizona’s "sky islands," and part of the range of the endangered southern jaguar and the ocelot as well as nearly a dozen other endangered and critical species. Overall, around 3,653 acres of the Coronado National Forest will be impacted by the mine's operation.

In August 2019, a federal judge rejected the Forest Service's plan for the open-pit mine, ruling that there were several problems with the agency's 2017 approval, and the 2013 final impact statement which cleared the way for the approval. U.S. District Judge James A. Soto also blocked the company, Toronto-based Hudbay Minerals, from beginning construction of the proposed $1.9 billion mine.

However, in February, lawyers for the Forest Service asked the 9th Circuit Court of Appeals to allow the mine to go forward and deposit tons of waste rock on federal land.

Under the plan, Rosemont would blast a mile-wide, half-mile deep pit to extract rock over the next 20 to 25 years, and in the course of digging through 3,000 feet of geological material, the mine will "penetrate the wall of the groundwater table" under the mountains, and the company plans to pump groundwater out, Soto wrote. However, after the mine ceases operations, the company plans to turn off the pumps, and the pit will become as "hydraulic sink" and fill with groundwater.

Fish and Wildlife said that the loss of groundwater that feeds a spring could harm a population of the succulent that lies just beyond the proposed Rosemont Mine. "The loss or reduction of groundwater, stream flow, or spring flow in or near a Bartram's stonecrop population due to mining-related activities could lead" to the plant's extinction, the agency said.

"Federal protection for Bartram’s stonecrop is more than 40 years overdue,” said Randy Serraglio, a conservation advocate at the center. "The beautiful little plant faces threats at every turn, from the ecologically disastrous Rosemont mine to uncontrolled livestock grazing and historic drought driven by climate change. Without the Endangered Species Act, the stonecrop would have little hope of survival."

"Due to the small size of the stonecrop’s populations — more than half of the 50 known populations contain fewer than 50 individuals — the species is particularly vulnerable to an array of threats, including water withdrawal for mining and other uses, fire, livestock grazing, climate change driven drought and poaching," the Center said.

One colony of the plant, in the Empire Mountains, southeast of Vail, has already completely collapsed, the agency noted.

Many currently undeveloped areas of  mineral deposits may be explored or mined in the future, the agency said. "We do not know the full extent of future mine activity within Bartram's stonecrop's range," the agency said, however, that there are 12 currently ongoing or proposed mining operations within 5 miles of Bartram's stonecrop populations in Arizona.

Fish and Wildlife warned that the plant is also threatened by poaching, and could be trampled by cattle.

Four populations of the stonecrop were recently lost due to the drying-out of its habitat, in part because of the loss of water in the region, and the little plant has also been affected wildfires.

Fish and Wildlife said that there have been 11 wildfires in known Bartram stonecrop sites from 2007 to 2017, which killed some plants and removed shade for others.

Support TucsonSentinel.com today, because a smarter Tucson is a better Tucson.

"Although we do not have pre-fire population counts in any population, two of the largest Bartram's stonecrop populations occur in sky island mountain ranges that have had the fewest acres burned from 2010-2017, which indicates these populations may have experienced less of the detrimental effects of fire than smaller populations," the Fish and Wildlife said.

However, "wildfires have burned in all nine sky island mountain ranges of southern Arizona with known Bartram's stonecrop occurrences within the last decade," the agency said. "Wildfire could potentially cause extirpation of small Bartram's stonecrop populations throughout the range of the species and have negative impacts on larger populations." 

The agency also noted that an invasive grass, known as Lehmann's lovegrass, does well following fires, and could actually increase the number and severity of wildfires, threatening the stonecrop's survival. 

This combined with increased warming and future droughts could also undermine the plant's survival, the agency warned.

- 30 -
have your say   


There are no comments on this report. Sorry, comments are closed.

Sorry, we missed your input...

You must be logged in or register to comment

Read all of TucsonSentinel.com's
coronavirus reporting here »

Click image to enlarge

Alan Cressler/Center for Biological Diversity

Bartram's stonecrop