The U.S. Forest Service is trying to protect an animal on the endangered species list from being buried alive by monsoon floods and sediment left behind after last month's Murphy Complex Fire south of Green Valley.
The Chiricahua Leopard Frog is getting some help from the Burned Area Emergency Response team, or BAER, after an assessment deemed the area around the frogs' habitat a "value-at-risk." The BAER team's goal is to reduce the potential damage that sediment and erosion could cause Peña Blanca Lake and nearby Ronquillo Pond once monsoon season is in full effect.
"We're trying to keep as much sediment as we can out of (Ronquillo Pond) to minimize the impact from the fire," said BAER assessment team leader Paul Guarnaccia during a visit to the pond Wednesday.
The BAER team decides how the soil will react to post-fire weather, such as monsoon storms, and how the water will roll off the soil's surface. Their main concern is watershed overflow from nearby Alamo Canyon Wash and Peña Blanca Canyon Wash.
"After the fire burns through, you literally have little to no vegetation left on the surface to collect and slow the water down," said John Hays, Santa Cruz County floodplain coordinator. "Without that vegetation there, you see more water hitting the ground and moving faster."
Faster moving water is erosive and can pick up a large volume of sediment in a short amount of time, Hays said.
"If you get a high volume sediment flow after a storm, you could basically bury the landscape," he said. "Anything that burrows would be buried in a choking mud that they couldn't get oxygen from."
To combat this problem, the BAER team is installing biodegradable mesh tubing called "straw wattles" around Ronquillo Pond and parts of Peña Blanca Lake. These tubes filter sediment that could enter these areas during a monsoon storm by slowing the flow of water.
The straw wattles used around Peña Blanca Lake are 12 inches in diameter and are staked into small trenches dug around the containment area. Hays points out that the effectiveness of the wattles depends on how much water is flowing through the area.
"If you got a flow that's about two feet high, the straw wattle isn't going to do much," Hays said. "But if you're talking about a flow that is only a few inches high, it's going to work well."
It all depends on how much rainfall collects on the soils surface at a given time and how fast the soil will absorb the water, he said.
Even though the Murphy Complex Fire and the adjacent Bull and Peña fires scorched more than 85,000 acres of forest, the severity of the burn overall was not as extreme as some of the other fires in the area, Guarnaccia said.
"It was a cool burn in a lot of places," said Guarnaccia. "You'll get a lot of re-sprouting when water comes back into the system."
In fact, plant life around Ronquillo Pond and Peña Blanca Lake has begun to re-sprout since the fire, due to recent monsoon storms.
The lake is currently closed to the public due to fire damage and crews repairing nearby power lines. Officials say the Forest Service plans to re-evaluate the area in a month to determine if it's safe to re-open to the public.
In the meantime, the BAER team is focused on protecting the Chiricahua Leopard Frog from flooding and sedimentation.
"Any place where there is a population of Chiricahua Leopard Frogs is going to be deemed a value-at-risk," said Guarnaccia. "Anything we can do to improve, weatherize and give some stability to the habitation during the monsoon season is what we're looking to do."