RED CLIFFS DESERT RESERVE – More than 10 years after devastating wildfires swept through the Red Cliffs Desert Reserve, biologists are testing a new way to rehabilitate burned desert tortoise habitat.
Mohave desert landscapes are not adapted to wildfire because plants and shrubs were too widely spread to carry a fire very far. However, invasive annual species such as cheat grass now provide a continuous fuel source that can fuel fires which take decades or centuries to heal.
This week, the Utah Division of Wildlife Resources staff along with AmeriCorps volunteers have been busy putting 1,000 plants in the ground in a 100-acre plot off Cottonwood Road.
It is hoped that container-grown native species planted in groups will survive and form islands which will then seed and spread to the surrounding areas.
Division of Wildlife Resources biologist Ann McLuckie is excited about the project. She is hoping as much as 70-80 percent of the plants survive, and grow big enough to spread.
The BLM spent over a million dollars in the year 2000 buying seeds and spreading it by airplane, McLuckie said, however, the survival rate was less than 5 percent.
“If you don’t rake it into the ground, then the seed is very vulnerable to drying out or being eaten by small mice or rodents,” McLuckie said.
Fires in 2005 destroyed tortoise habitat, followed by a very heavy precipitation year that triggered damaging floods in Southern Utah.
“There was just tons of growth, I mean we had weeds up to the waist. It was phenomenal how much fuel was in the desert,” McLuckie said. When summer came, the vegetation dried out and an active monsoon season with lots of lightning started numerous fires and heavy growth carried the fires quickly.
“That was when we had a whole series of fires that pretty much burned a quarter of tortoise habitat within the Reserve,” McLuckie said. “It was pretty significant.”
The wildfires resulted in a drop in tortoise populations of up to 50 percent, McLuckie said, and populations have not rebounded. Now the goal is simply to make sure the tortoise population is healthy and doesn’t drop any further.
“We may never have that number (of tortoises) that we once had because we now we have all of these other factors that we have to think about like invasive grasses that we will never get rid of. We’ll have to just be able to somehow control them to a point where we don’t have to worry about fires.”
In addition, high-density human populations bordering the reserve keep the tortoises from wandering.
“Things have changed and we may never get to those high numbers that we once had, but we do want to focus on making sure populations are healthy and that they don’t further decline,” McLuckie said.
Planting for food, shade
A thousand plants of four different native species were planted in the Red Cliffs Reserve to provide both food and shade for the tortoises.
Big galleta, brittlebush, white bursage and globemallow were planted; the plants were grown from seeds collected locally or elsewhere in the Mohave desert. Local seeds can survive better because they are adapted for the area.
The original plan was for 5,000 container-grown plants to be planted in the Red Cliffs Desert Reserve this fall, but only 1,000 will be planted this season.
“The effort on the Beaver Dam was so intense, in terms of planting, that we requested that he only deliver 1,000,” McLuckie said.
A similar effort has been underway in the Beaver Dam Wash National Conservation Area.
“We’re looking at this kind of like as a pilot study, so that when we get the remaining 4,000 that we’ll have a better idea of what methods best increase survival and reduce personnel effort – what are the most efficient planting methods that increase survival,” McLuckie said.
Half of the plants will be caged and half will not, to look at whether it helps the plants survive. Biologists will also be watching plant density and diversity at the planting sites, to see which methods have the most success.
“We’re looking at, if you plant a bunch of plants together does that increase survival or not?” she said.
The plants will be watered once a week until they are well-established, then once a month. During the hot summer months, a weekly watering schedule will resume.
“If they survive one year, we can certainly start backing off and maybe stop watering them,” McLuckie said.
“But we want to make sure we provide as much water as we can so that we increase their survival, because, you know, it’s a lot of effort to put plants in the ground.”
While the threatened desert tortoise is the subject of a lot of funding and focus, efforts to conserve the animal also helps other species such as deer and rabbit, McLuckie said.
“We consider the tortoise as an umbrella species. So if you benefit the tortoise, then we’re also benefitting other native species that are here.”
The project is a joint effort between the Bureau of Land Management, The Nature Conservancy, Utah Division of Wildlife Resources, U.S. Fish and Wildlife Service, Washington County, the National Fish and Wildlife Foundation and the University of Nevada, Las Veg
“No agency had to fund the project in its entirety,” McLuckie said.
Fish and Wildlife Service contributed $40,000, Watershed Restoration Initiative spent $30,000, Red Cliffs Desert Reserve spent $20,000 and more than $12,000 came from The Nature Conservancy. In addition, the Bureau of Land Management funded American Conservation Experience volunteers.
Volunteers will be needed in 2017 to help plant an additional 1,500 plants, McLuckie said.
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