Recent accomplishments of CDFW's scientific community
Wildlife Officer Pat Freeling replanting dudleya.
Wildlife Officer Will Castillo replanting dudleya.
Last week, a team of California Department of Fish and Wildlife (CDFW) staff and volunteers spent hours working to replant than 2,000 Dudleya succulents that were seized after a poaching investigation. The plants were meticulously returned to the Mendocino and Humboldt county cliffs from where they were stolen weeks before.
The sheer volume of plants made it necessary to put a call out for help from volunteer botanists. The response was overwhelming. More than 20 succulent experts from the California Native Plant Society and U.C. Santa Cruz arboretum, along with National Parks Service personnel, assisted CDFW wildlife officers and seven environmental scientists on the replanting project. The replanted succulents will be monitored over the next week to ensure the greatest chance for survival.
CDFW Environmental Scientist Michael van Hattem calls Dudleya “the botanical version of abalone,” in the sense that they are a sensitive species, dependent on a very specific habitat. Without a concerted effort to reverse the effects of such a large poaching operation, he says, the ecosystem would be irreversibly damaged.
In March 2018, CDFW law enforcement officers uncovered an international conspiracy to strip the succulents from sea cliffs and ship them overseas to other countries, including Korea and China, where they are prized for decorative purposes. So far, there have been three significant poaching investigations. In the first case, prosecuted in Mendocino County, the subject was found guilty and fined $5,000. A second case is also currently pending in Mendocino County.
The third recent case was out of Humboldt County, where wildlife officers seized well over 2,000 succulent plants from three suspects. Prosecution of that case is also pending. This week, the Humboldt County District Attorney’s Office released all but 10 of the plants from evidence to allow the team to replant them at the location where taken.
“Our wildlife officers and partners have gone to extraordinary length to investigate and stop a new poaching threat in California,” said David Bess, Deputy Director and Chief of the Law Enforcement Division. “We can't think of a better project to work on through Earth Day weekend.”
CDFW Photos. Top Photo: Wildlife Officer Will Castillo replanting a Dudleya succulent.
Native to the California coast and the California/Nevada state line, the Myrtle’s silverspot butterfly feeds on the nectar of the monardella flowers.
One of 33 species of birds listed as threatened or endangered by the State of California or the federal government, the western snowy plover is in jeopardy of disappearing from the dunes.
in 2017, two years after treatment, the southwest side of the herbicide treatment area shows little regrowth of invasive plants.
Sandy dunes along the California coast often feature hardy European beachgrass and a succulent, freeway iceplant, that many assume is part of the native flora. However, these groundcover plants were originally introduced in the 1800s by Gold Rush settlers who were hoping to keep sand from moving to the nearby roads, railroads and land. Today, they are invasive species that out-compete the native plants and the animals that live there.
Over the years, the invasives took over the native Tidestrom lupine and beach layia, causing them to be placed on the federally endangered species list. The endangered Myrtle’s silverspot butterfly and the threatened snowy plover are dependent on native plants like these, and today, they too are in jeopardy of disappearing from the area.
“Snowy plovers naturally select open areas to nest so that they can more easily spot predators,” said CDFW Environmental Scientist Laird Henkel. “The European beachgrass spreads quickly making the dunes less desirable as a place for these birds to nest.”
Scientists determined that removing these invasive plants would be the best way to restore the dunes and the ecosystem that depends on them. To this end, CDFW awarded $54,000 in Environmental Enhancement funds to a project on the Point Reyes North Great Beach, located in Marin County, to restore the native sand dune plants on a 13-acre area in 2015. The fund committee selected the Point Reyes application because of the success of their previous dune restoration projects.
Point Reyes National Seashore staff oversaw the removal of the invasive plants on the dunes. Their contractors spray-treated the dunes with an herbicide and uprooted the invasives by hand; they worked during times of low winds and no rain, to protect other natural plants, wildlife, nearby farms and the public from overspray.
Point Reyes scientists monitored the treated area with an easy-to-use mapping tool called photo point monitoring – an effective method of monitoring vegetation and ecosystem change. Visual surveys and the mapping program showed just a one-to-three percent regrowth of the invasive plants over time, while previous restoration projects showed much more regrowth.
“The project area represents a vital link between earlier restoration efforts near Abbotts Lagoon and new restoration efforts at the AT&T cell tower area, enabling the park to move closer towards its goal of several miles of dune habitat not wiped out by invasive plants such as European beachgrass and iceplant,” said Point Reyes National Seashore Ecologist Lorraine Parsons.
CDFW-OSPR and the Point Reyes staff consider the project’s first objective – eradicating invasive European beachgrass and ice plant – a success. Earlier this year, scientists noticed in treated areas the reappearance of wild cucumber. The reappearance of other native plants such as the mock heather, California blackberry and yarrow, and wildlife is the second objective, the success of which will be determined over time. Other treated areas in the region show beachgrass breakdown and increased native dune scrub and mat species after six years.
Photos courtesy of Point Reyes National Seashore and the U.S. Fish and Wildlife Service.
Top photo: The Point Reyes National Seashore staff oversee contractors spray-treating the dunes with an herbicide.
Lassics lupine grows under protective cages.
Richard Macedo, Habitat Conservation Planning Branch Chief constructs a cage to protect rare, endangered Lassics lupine.
Lassics lupine grows under protective cages.
Biologists from three government natural resource agencies banded together this summer in an unusual effort to help preserve a species under threat of extinction. They lugged materials to build wire cages into the rough terrain of the remote Lassics mountains near the border of Humboldt and Trinity counties in an effort to protect their target. However, these cages were not built to trap animals; they were constructed to keep animals out.
The barren, green serpentine slopes of Mount Lassic, located in a seldom-visited part of Six Rivers National Forest, are home to one of California’s rarest plants: the Lassics lupine (Lupinus constancei). Lassics lupine is a short plant in the pea family that has bright rose-pink flowers. Only approximately 450 adult Lassics lupine plants were observed during 2017 monitoring of the species conducted by the U.S. Forest Service and the U.S. Fish and Wildlife Service, with assistance from CDFW.
Rodents such as deer mice, squirrels and chipmunks have been eating so many Lassics lupine seeds from the plants that, absent intervention, the species appears to be on the path to extinction within the next 50 years (Kurkjian et al. 2016).
Biologists believe that historical suppression of fires in Six Rivers National Forest beginning in the early 1900s may be indirectly responsible for the encroachment of forest and chaparral into Lassics lupine habitat. Fires that were put out quickly did not grow large enough to reduce encroaching forest, and therefore the forest expanded. With the encroaching vegetation came more seed-eating rodents that depend on vegetation cover for protection from predators.
In 2003, the U.S. Forest Service, U.S. Fish and Wildlife Service and other researchers began an emergency attempt to halt Lassics lupine’s trend towards extinction. Each summer, biologists set off on the laborious hike up Mount Lassic to place cylindrical wire cages over as many flowering Lassics lupine plants as possible. Each cage is anchored to the ground to prevent rodents from squeezing underneath.
The cages are remarkably effective at stopping rodents when properly installed, and they remain on the plants for the duration of the growing season. After Lassics lupine fruits have matured, they often split open suddenly and send seeds flying through the air up to 13 feet away. The cages are then removed each year before the onset of winter snow.
“Protecting endangered species is California’s policy and plants like the Lassics lupine could disappear within our lifetimes,” explained Jeb Bjerke, a biologist with CDFW’s Native Plant Program. “We should do what we can to save these unique plants for the future.”
In 2015, in the midst of an historic drought, an 18,200-acre fire spread through the Lassics, killing many Lassics lupine plants and charring the chaparral vegetation nearby. The fire had little effect on the forest that encroaches into Lassics lupine habitat, but preliminary studies suggest that the fire may have reduced rodent density in the burned chaparral. Despite the apparent reduction in rodent density following the fire, the impact from rodents eating Lassics lupine seeds remains high. Continued caging of Lassics lupine plants therefore remains critical for preventing extinction of the species until a more permanent solution can be implemented, such as significant reduction of encroaching forest. However, such efforts are expensive to plan and implement. As the primary land manager, the U.S. Forest Service would likely be the lead agency in future protective actions.
In 2016, the California Fish and Game Commission received a petition to list Lassics lupine as an endangered species under the California Endangered Species Act and the species was designated a candidate species earlier this year. CDFW is in the process of producing a status review for Lassics lupine that will include a recommendation to the California Fish and Game Commission on whether listing the species is warranted. The legislature directs all state agencies, including CDFW, to seek the conservation of endangered and threatened species.
“I hope that CDFW can continue to partner with the U.S. Forest Service and U.S. Fish and Wildlife Service to protect the Lassics lupine from extinction,” Bjerke said.
For additional information on this subject, please see:
California Department of Fish and Wildlife photos by Jeb Bjerke
Brush habitats were created and put into Lake Perris to provide fish with habitat to feed and reproduce. The habitats will be completely submersed when the lake is filled to capacity.
The exposed lakebed gave CDFW fisheries biologists the opportunity to safely construct different kinds of habitat for the fish in Lake Perris.
Rock Reefs and Spawning gravel areas have been created and placed in more than 100 places around Lake Perris that will be utilized once the lake is returned to full capacity.
Rock Reefs constructed along the shore of Lake Perris, most about 1,000 square feet provide cover for juvenile fish and forage species.
135 Pipe Caves were constructed from PVC pipe and will provide spawning habitat for catfish.
Biologists created about 1,500 brush habitats in hundreds of locations on the banks of Lake Perris and in accessible locations further into the lake.
Biologists created about 1,500 brush habitats in hundreds of locations on the banks of Lake Perris and in accessible locations further into the lake.
More than a decade ago, Southern California freshwater anglers were disappointed to see a tried-and-true fishing spot dramatically affected by an emergency lake drawdown. Due to seismic concerns with the Perris Dam, California Department of Water Resources (DWR) officials deemed it necessary to reduce the water level at Lake Perris near Riverside by several thousands of acre-feet.
The drawdown exposed about 25 feet of bank around the perimeter of the lake. Since water was not going to be available for years while the dam was assessed and repaired, CDFW embarked upon a fisheries habitat mitigation project (funded by DWR) to create new fish habitat in the remaining water and the now exposed lakebed.
The project had two phases. The first was to immediately create fisheries habitat in the drawn-down portion of the lake in order to maximize use of the remaining water. The second was to build new habitats on the temporarily exposed areas, with the hope of benefitting both sport-fish species and anglers when the lake is eventually refilled.
After 12 years, both phases are nearly completed.
After the initial water level reduction, teams from CDFW and DWR began working to prevent the immediate collapse of the lake’s fishery. The initial work, which took three years, involved the creation and placement of about 400 fish habitats made of recycled Christmas trees and citrus limbs. The man-made shelters ensured the fish would have places to hide and reproduce.
After the initial triage, CDFW biologists began to place additional habitats into the remaining water of Lake Perris. These habitats, made of thousands of tree trunks, citrus limbs and whole tree stumps would eventually give the lake’s fish an additional 1,500 refuges for safety.
The citrus limbs were drilled with a ½” hole in the base and multiple limbs were tied together as compactly as possible and attached to a concrete block with polypropylene ropes to weigh them down. They were then placed strategically in different parts of the lake. These citrus habitats should provide cover for the warm water fish for at least 10 - 15 years.
Due to their bulk, increased buoyancy and weight, the single tree stumps were placed individually around the lake and weighted down with concrete blocks to keep them anchored.
Because the lake will be refilled to capacity once dam repairs are complete, it is important that the scientists are able to carefully track each habitat location. They worked in quadrants, placing 20 - 60 bundles into each to create “communities.” The grouped communities increase localized productivity of the warm water fish native to the lake and contribute to maintaining the warm water fisheries while the lake is in its reduced capacity. Each of the quadrant’s corners was marked with GPS, enabling scientists to record and monitor data specific to each location.
The second phase of the project was the implementation of a Fishery Habitat Plan for the exposed lakebed above the drawn-down area. The implementation of the plan is a requirement of the Lake and Streambed Alteration Agreement between CDFW and DWR.
As with the below-water work that had already been completed, CDFW scientists carefully planned what kinds of habitat to create, what materials to use and where to place them in the open, exposed lakebed in order to provide the best environments for fish when the lake was fully restored. Areas were selected for habitat placement based on accessibility, proximity to existing natural habitat directly affected by the water reduction, avoidance of areas utilized for construction activities, distance from swimming areas and consideration of boating hazards.
Multiple types of habitats were designed and installed in Lake Perris, including:
CDFW Photos. Top Photo: Citrus tree stumps, weighted down with concrete blocks to keep them anchored were placed individually around Lake Perris to create small habitats called communities.
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The tilapia skin is visible on the bottom of the bear's paw.
Veterinarians perform an ultrasound to check on the progress of the second bear's pregnancy.
Acupuncture needles assist with pain management.
After placing the second bear, the team moved the first bear to another location where another man-made den awaited.
CDFW staff work together to build a makeshift den for a soft release in Los Padres National Forest. A soft release involves putting the bear in a den to simulate hibernation, and leaving it to wake up on its own.
Two talented veterinarians, an environmental scientist and several dedicated staff members at the CDFW Wildlife Investigations Lab recently put their heads and their resources together to help heal a pair of adult bears that were badly burned in the Thomas Fire. The bears, which were treated at the same time as a young mountain lion with similar, less severe burn injuries, were released back to the wild last Thursday, after several weeks of intensive – and unusual – care.
CDFW Senior Wildlife Veterinarian Dr. Deana Clifford was acting manager of the Wildlife Investigations Lab in Rancho Cordova when the first bear – an adult female weighing about 200 pounds – was captured inside of a backyard aviary in the Ojai area on December 9. With CDFW Environmental Scientist Christine Thompson coordinating, CDFW Wildlife Officer Jacob Coombs darted the bear and local veterinarian Dr. Duane Tom evaluated its injured paws and overall condition. Thompson then conferred with Clifford, who determined the bear might have a chance at recovery if treated quickly. The bear was put into a trailer for the seven-hour transport to Rancho Cordova, where Clifford was waiting.
By the time the bear arrived, Clifford had already reached out to Dr. Jamie Peyton, Chief of Integrative Medicine at the UC Davis Veterinary Teaching Hospital, for help. Weeks earlier, Peyton, who works mostly on domestic animals, had mentioned to Clifford in passing that she had a particular interest in animal burns, and would be interested in helping wildlife if the chance ever arose.
Peyton created a homemade burn salve for the bears’ paws, and a process for sterilizing tilapia skin. Fish skin, which contains collagen, is often used by doctors in Brazil to bandage human burns. The technique is not yet approved by the Food and Drug Administration for use in the United States, and had not been tried on veterinary patients.
To help keep the tilapia skin in place, Peyton cut pieces to exactly match the size of the bear’s paws and then sutured them over the wounds while the bear was under anesthesia. Additional temporary wrappings, including rice paper and corn husks, were added, with the intention of stretching out the amount of time it would take for the animal to chew down to the fish skin bandage. “We expected the outer wrapping to eventually come off, but we hoped the tilapia would keep steady pressure on the wounds and serve as an artificial skin long enough to speed healing of the wounds underneath,” Peyton said. She also used acupuncture to aid the bear with pain management.
The original plan was for Peyton to come to the lab weekly to check on the bear’s progress. But within just a few weeks, two more burn patients arrived from the Thomas Fire. A second adult female bear, found relatively close to where the first one was found, was brought to the lab by Thompson on December 22. And on December 23, the young mountain lion arrived from Santa Paula. The experimental tilapia treatment was extended to the two newcomers as well.
Of the three animals, the mountain lion’s injuries were the least severe. Because of his young age, he was earmarked for placement in a wildlife rescue facility. The two bears were in much worse condition, with oozing wounds and, in some cases, paw pads that were completely burned off. But because the bears were older and stronger, the veterinarians hoped to return them to the wild if their injuries could be healed.
To complicate matters further, on December 28, during a routine burn treatment, Clifford’s team performed an ultrasound on each bear, and found that the second bear was pregnant. The quest to heal the mother-to-be was now a race against time.
“That was a game changer for us, because we knew it wouldn’t be ideal for her to give birth in confinement,” Clifford said. “We aren’t really set up to have a birth at the lab holding facilities, and we knew there was a high probability that she could reject the cub, due to all the stress she was under. We needed to get her back into the wild as quickly as possible.”
While Clifford and Peyton continued to focus on healing the animals’ injuries, Thompson started scouting out potential release locations. Since both bears needed to be transported back to Southern California, it was decided to try to return them at the same time – albeit not exactly in the same location – in order to make the best use of staff time and resources.
Both bears’ original habitat had been destroyed by fire, so Thompson scouted for two new locations that fit several parameters. The bears needed to be close to their home range, but not within the burn area, and near ample food and water sources. She also wanted to keep them as far away from each other as possible. “A lot of wildlife habitat was destroyed by the fire, and there are already a lot of displaced animals roaming around,” Thompson said. “So there’s a good chance that whatever location we choose is already occupied by other bears, but only they know exactly where that designated territory is. The best we can do is make an educated guess, and place them as deep into wild lands as possible.”
Taking the rapidly changing winter weather reports into careful consideration, the team chose Wednesday, January 17, as the target date to get on the road. That morning, Peyton came to the Wildlife Investigations Lab one last time and both bears were immobilized for a final treatment for their feet. Then the bears were placed into separate transport trailers for the long journey home. Simultaneously, in the Los Padres National Forest, Thompson and Tom spent the day digging dirt and moving logs to create a winter den for each bear.
“At this time of the year, most bears have established dens for the winter, but since these bears won’t have time to create a den, we hope to improve their chances of survival by creating a den for them so they have a home base and shelter right away,” Clifford explained.
The team arrived late Wednesday night, and both staff and bears were hosted overnight by the Ventura County Sheriff’s Department. Early on the morning of January 18, Clifford, Thompson, Coombs, Tom and their team drove the bears deep into the forest for the final leg of their journey. One at a time, each bear was sedated and carefully placed into her den, while the team finished constructing a shelter around the slumbering animal. The bears are about five miles apart, as the crow flies, and each is wearing a satellite collar so CDFW can monitor her movements and survival post-release. Staff also placed trail cameras near each den.
“We’re really hopeful that these novel treatments accelerated the healing for these bears and provided them the best odds of survival,” Clifford said. “It’s especially good to know that we’ve maximized the odds of survival for the cub on the way. We don’t know exactly when it will be born, but hopefully we’ll be able to monitor the movements of the mother via satellite, and that will give us an indication of how things are going.”
For Clifford, the entire experience wasn’t simply about saving the lives of two bears. The bigger picture involves the body of knowledge the experimental treatment provided – both to the Wildlife Investigations Lab team and to the UC Davis Veterinary Teaching Hospital.
“This treatment has the potential to be used successfully on all kind of burn patients, both domestic and wild,” Clifford said. “For us, at the Wildlife Investigations Lab, it’s been an invaluable experience because California’s changing climate means that we’re likely to see more wild animals impacted by catastrophic wildfires. By better understanding what resources are needed to care for injured wildlife and what treatment techniques increase healing speed, we can make the most informed treatment decisions, reduce animals’ time in captivity and provide guidance to other facilities caring for burned animals.”
CDFW photos. For more, please see CDFW’s Flickr photo album: Thomas Fire Bears.
Top photo: The first bear rests in her holding enclosure after her treatment is finished. The outer wrapping on her feet (made of corn husks) will delay her efforts to chew off the tilapia skin bandages underneath.
A tiny transponder is placed inside the body cavity of each female salmon. When the fish lay their eggs, the transponders will be expelled, providing scientists with information on when, where and how successful each spawning female is.
After the salmon are tagged, they are returned to a holding pond while the anesthetic wears off.
CDFW scientists electronically identify and perform an ultrasound on each fish in order to assess their pre-spawning condition.
Each salmon in the project received a tiny identity tag that is entered into a database. The computerized system allows biologists to follow individual fish throughout their life cycle.
A team of scientists read, evaluate and record data for each individual salmon.
On Thursday, May 18, fisheries biologists implanted acoustic transponders into 60 endangered adult spring-run Chinook salmon. The transponders will track their movements and help determine spawning success later this season. The salmon will be released to spawn naturally in the San Joaquin River near Friant over the next three months.
Spring-run Chinook have been absent from the river for many decades. Reintroduction is one of multiple strategies biologists are using to reestablish naturally spawning runs of these fish as part of the San Joaquin River Restoration Project. The project – which is jointly coordinated by CDFW, the Bureau of Reclamation, the California Department of Water Resources, the U.S. Fish and Wildlife Service and the National Oceanic and Atmospheric Administration’s National Marine Fisheries Service – is a comprehensive, long-term effort to restore flows to the San Joaquin River from Friant Dam to the confluence of the Merced River and restore a self-sustaining Chinook fishery while reducing or avoiding adverse water supply impacts from restoration flows.
A total of 120 salmon will be implanted and released at two different times. Biologists will track the fish from each release to determine which is most successful. This release strategy provides the hatchery-raised salmon the opportunity to select their own mates, construct redds (a spawning nest in the stream gravel) and spawn naturally.
CDFW photos by Harry Morse
These pregnant females will bolster the population of a newly established herd as well as provide an infusion of fresh genetic material to helps ensure their new herd’s health and long-term survival.
Outfitted with an ear tag and two tracking collars, this ram awaits delivery to a new herd where it’s hoped he will infuse the population with fresh genetics
Among the goals of the Sierra Nevada Bighorn Sheep Recovery Plan is the establishment of 12 viable herds across their historic range. CDFW’s capture and relocation efforts over the years have helped establish 14 herds today across 150 miles of their historic range.
These Eastern Sierra bighorn sheep are being prepared for their flight to a new home and new herds.
Can just seven Sierra Nevada bighorn sheep really make much of an impact on the species’ future?
CDFW scientists believe so, which is why they came away pleased with the results of their annual spring helicopter capture this past March. Limited to three days of work due to strong winds and bad weather, the effort resulted in the capturing, collaring and relocation of seven sheep to new herds high in the Eastern Sierra.
Although the final chapters have yet to be written, the saga surrounding the Sierra Nevada bighorn sheep, one of the rarest large mammals in North America, is shaping up to be a 21st century wildlife success story.
A unique subspecies found only in the Sierra Nevada, historic populations numbered in the thousands. Their steep population decline began in the 1800s as a result of competition from livestock grazing, unregulated hunting and the transmission of disease from domestic sheep. Drought and predation further hammered their numbers, which dwindled to about 100 animals in just three herds by the mid-1990s. State and federal officials declared them endangered in 1999.
Today, less than 20 years removed from those dramatic listings, there are 14 different Sierra Nevada bighorn sheep herds spread across 150 miles of the iconic mountain range. About 600 bighorn sheep are now eking out a living atop the Sierra’s highest peaks. Sierra Nevada bighorn sheep are present once again inside Yosemite National Park and Sequoia National Park after a 100-year absence.
CDFW’s role is itself unique as a state agency tasked with leading the recovery of a federally listed endangered species. Sierra Nevada bighorn sheep are recolonizing their historic range – with a major assist from CDFW’s twice-yearly captures, collaring and strategic “translocations.”
This spring, three males and four pregnant females were captured from two established herds and translocated to two newly reintroduced herds – one along their western range inside Sequoia National Park and another herd in Inyo County at the southernmost extent of their range.
“Whenever we start these new herds, we like to move a minimum of 20 females as well as additional rams over time,” explained Tom Stephenson, a CDFW senior environmental scientist based in Bishop and the leader of the Sierra Nevada Bighorn Sheep Recovery Program. “At that point, we feel the population has enough animals to begin growing at a high enough rate and also has sufficient genetic diversity.”
Before the animals are relocated, a CDFW team records their vital statistics. Ultrasound machines are used to measure body condition and determine pregnancy status. The animals are outfitted with identifying jewelry – color-coded ear tags, VHF and GPS collars that allow biologists to identify them and track their movements for years in some cases.
All the high-tech, intensive monitoring has paid dividends with new appreciation and understanding. Once believed to always migrate to lower elevations in the winter, CDFW scientists have learned that many sheep ride out the Sierra Nevada’s inhospitable winters at 11,000- to 14,000-foot elevations.
“They are really tough,” Stephenson said. “But they’re able to do that because they put on large amounts of body fat in the summer when they’re on quality habitat. They are essentially hibernating standing up in the alpine. They’ve got an environment up there that is wind-scoured so they can find some food. They’re not having to move around much, and they’re relatively free from predators when they’re up in those altitudes in the winter time.”
Not every sheep captured is relocated.
Helicopter crews this spring attempted unsuccessfully to capture rams in the northernmost part of their range, collar them and return them to their same herds. CDFW biologists are keeping close tabs on the Mount Warren Herd near Lee Vining in Mono County in particular and its proximity to domestic sheep grazing on public land. Sierra Nevada bighorn sheep are disease-free and CDFW biologists want to keep them that way.
While populations have met or exceeded some recovery goals, eliminating disease – or the risk of disease – remains a significant benchmark and key to delisting or down-listing the species from endangered status.<
“There are a lot of bighorn sheep populations throughout the West that continue to struggle with disease,” Stephenson said. “So we’ve worked really hard with public land managers as well as private individuals in the Eastern Sierra to try and ensure our bighorn sheep don’t come into contact with domestic sheep.”
CDFW photos courtesy of Andrew Di Salvo. Top Photo: A helicopter crew delivers four bighorn sheep to CDFW's base camp where vital statistics were recorded, blood was taken, and the sheep were outfitted with identifying ear tags and tracking collars.
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