CEDAR CITY — As the once-vast sagebrush sea becomes fragmented, habitat loss puts native plants and animals at risk, including a rabbit that can fit in the palm of your hand. Conservationists, concerned for the pygmy rabbit’s future, petitioned the U.S. Fish and Wildlife Service to grant the tiny critter federal protection.
Pygmy rabbits are the world’s smallest rabbit species, weighing between 1/2 to 1 pound, according to a news release from the Western Watersheds Project. Brachylagus idahoensis is specialized to the sagebrush and grass habitats found in the Sagebrush Sea in Wyoming, Idaho, Nevada, Colorado, California, Oregon and Utah, where they can be found throughout the state, including Iron County.
The animals are at risk of extinction due to habitat loss and disease. According to the news release, the Sagebrush sea has seen an estimated loss of 1.3 million acres yearly due to stress caused by various factors, including development, fossil fuel extraction, livestock grazing, drought and wildfires.
This “cute, little ball of fuzz” typically lives in the tallest, densest sagebrush, Kimberly Hersey, a mammal conservation coordinator with the Utah Division of Wildlife Resources, told Cedar City News.
Pygmy rabbits rely on healthy sagebrush habitats for food and cover from predators. They require deep soil to construct burrows for shelter and the safety of their young, the release states.
Another threat to the species is Rabbit Hemorrhagic Disease Virus Serotype 2, which was first detected in pygmy rabbits in 2022, Allison Jones, a conservation biologist who contributed to the petition, told Cedar City News. The disease is specific to lagomorphs and is “super deadly,” with a mortality rate of up to 100% once it infiltrates burrow systems.
Some surveys indicate that pygmy rabbit populations have “dwindled” over the past 50 years. And Utah has “alarmingly low occupancy rates,” ranging as low as 7-13%, the Western Watershed Project states. In Wyoming, the species declined by 69%, and occupancy rates in Nevada and Idaho are just below 25% in both states.
A coalition of conversation groups, including the Western Watersheds Project, Center for Biological Diversity, WildEarth Guardians and Defenders of Wildlife, submitted a petition to the U.S. Fish and Wildlife Service to protect the rabbit and, by extension, its habitat.
There were two previous proposals to list the lagomorph under the Endangered Species Act in 1991 and 2003 but the U.S. Fish and Wildlife Service determined the species did not warrant listing.
While the service acknowledged that the rabbits were at risk, it stated that there was not enough data showing that threats affecting the animals put them at risk for extinction, the release states.
The pygmy rabbit has also been a species of concern for the Utah Division of Wildlife Resources for “quite a long period of time,” Hersey said, adding that the division partners with universities and federal agencies to study various factors impacting the animal, including how to prevent burrow disturbance and where populations are concentrated.
“We make sure they (federal partners) know where those occupied areas are and then we can help them prioritize protection for those areas,” she said.
However, while the division is monitoring the species, Hersey said she agrees that federal listing is not currently warranted. And said it could limit the strategies that can be used to track and conserve populations across the state that live in various climates and conditions and face different threats.
Additionally, Hersey said Utah’s occupancy rates in the petition don’t align with the division’s surveys, despite the authors using her as a resource, as “occupancy completely depends on how you define your sample.” And habitat models can be a great tool for narrowing down rabbit locations but researchers need to “key into the right areas.”
For instance, the division created a habitat model for Rich County and found signs of pygmy rabbits in most plots they visited, leading the team to generalize the model throughout the state, Hersey said.
Because of this, they predicted higher occupancy than found in southwestern Utah, but researchers weren’t surveying the “right areas” based on a model that wasn’t specific to the region, Hersey said.
“Unless you’re using the same sample frame and the same survey method, you can’t compare across them,” she said.
Still, more study and monitoring of pygmy rabbits will be necessary going forward, Hersey said, adding that the division plans to conduct additional research in the near future to ensure their recommendations are working and that the species persists.
Federally listed species are given a “backstop” when something impacts their environment. The government will need to be consulted to determine if a plant or animal would be jeopardized, Greta Anderson, the deputy director of the Western Watersheds Project, told Cedar City News.
“One of the big problems” with pygmy rabbits is that they weren’t been tracked across their range, Anderson said. “And so getting some sort of comprehensive program that looks at, monitors and assesses impacts to the species is really the way, we think, to ensure their survival.”
Jones said the groups had been concerned about the “entire sagebrush biome” over the last few decades, as the ecosystem is threatened by frequent wildfires driven by climate change, drought and nonnative plants, particularly cheatgrass.
The cheatgrass infestation is related to other impacts on sagebrush habitat, Anderson said. Cheatgrass is more likely to grow in areas that are degraded by livestock grazing. Because the plant is highly flammable, it is more likely to be “destroyed through fire,” impeding the habitat’s recovery.
“For all intents and purposes, it permanently destroys the habitat for pygmy rabbits,” she said. “And couple that with spurts of development and other anthropogenic impacts in habitat — we know pygmy rabbits don’t go very far. They’re not big dispersers, so you’re creating all these little fragmented islands of habitat and each of those islands then is more likely to be destroyed.”
Another factor impacting pygmy rabbit’s habitat is juniper incursion, Hersey said. Juniper trees can “choke out” native grasses and other plants, including sagebrush, which may also contribute to invasive species gaining a foothold in the area.
A team of 94 scientists and specialists representing 34 federal and state agencies, universities and other organizations conducted a comprehensive assessment of the sagebrush ecosystem in 14 western states and two Canadian provinces, according to a news release issued by the U.S. Geological Survey.
They discovered that these habitats “continue to shrink rapidly” and have recommended continued conservation efforts to protect the ecosystem and more than 350 species located in the area.
While “sage-grouse conservation efforts are a great start,” continued work could be required to conserve other species, Tom Remington, Western Association of Fish and Wildlife Agencies coordinator on the project, said in the release.
“We can’t just assume that these alone are going to take care of mule deer migration routes, wintering areas, pygmy rabbits, pronghorn or human needs from these landscapes,” he said. “There are many examples where state, federal or private efforts are successfully addressing these challenges collaboratively. We can conserve the sagebrush biome if we coordinate our actions to emulate these and scale them up.”
The biodiversity and climate crises are intertwined, Anderson said, adding that these issues have a cumulative effect.
“We need better national policy and an increased awareness that — death by a thousand cuts — every little cut is mattering,” she said. “I would say caring about the pygmy rabbits is a great place to start, but caring about the fact that this major ecosystem in the United States is being lost at a rapid pace. …
“The pygmy rabbit is definitely suffering, but we’re all going to be in trouble if we lose this healthy, functional, carbon-sequestering landscape.”
Pygmy rabbits represent other species that are similarly tied to sagebrush, such as the sagebrush sparrow and sagebrush lizard, and are considered by some scientists to be a “canary in the coal mine,” which is one reason why the species was chosen for protection, Jones said.
Hersey said she disagreed with this description, however, contrasting them with greater sage-grouse, which is considered an umbrella species. This term describes when protecting one species will indirectly benefit multiple other plants or animals.
Sage-grouse inhabit large areas native to various sagebrush types, whereas pygmy rabbits inhabit a relatively smaller area, Hersey said.
“If you’re saving and protecting habitat for the sage-grouse, you’re going to protect a lot of these other species that use sagebrush, like the pygmy rabbit,” she said. “And the pygmy rabbit is really sort of the specialized, niche species within that sagebrush ecosystem.”
Anderson described pygmy rabbits as being similar to teddy bears and said that the public should “care about the cute things that are depending on us for their survival.”
“If you don’t care about protecting the cutest little critter in the West, you have no soul,” she said. “Like, how can you look at a pygmy rabbit and say, ‘I don’t care.’ It feels to me like this is the sort of quintessential critter that tell us something about life in the West and we should do our best to protect it so that our kids can see the cutest little critter.”
Read the full petition at this link.
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