Recent accomplishments of CDFW's scientific community
CDFW’s Yolo Bypass Wildlife Area serves two critical – but sometimes competing – needs.
The 16,670 acres of riparian and agricultural habitat in Yolo County provide a refuge and an all-you-can-eat buffet for migratory waterfowl and resident wildlife to the west of Sacramento and the increasingly urbanized surrounding communities.
The wildlife area is also a key cog in the Sacramento region’s flood control system. In wet years, the vast flood plain accommodates massive water diversions from the nearby Sacramento, Feather and Yuba river systems to prevent flooding in populated areas and to relieve pressure on strained river levees.
With the drought-busting rains and snow received last winter, the wildlife area resembled an inland ocean for the thousands of daily commuters traveling the Interstate-80 Yolo Causeway, which crosses the northern edge of the wildlife area. The floodwaters stretched as far as the eye could see, reaching depths of 20 feet in some places, and submerging almost every natural feature underneath. The consequences were dire for wildlife unable to escape.
Pheasants, deer, raccoons, and small rodents of all kinds were among the victims. Some were overcome by the rising water, some starved while waiting out the floodwaters in trees or isolated patches of high ground, others were picked off by predators stalking the water line for fleeing prey.
As a result, efforts are now underway to help the area’s wildlife survive future flooding. The Yolo County Resource Conservation District has secured almost $700,000 in Proposition 1 state water project funds to build two wildlife escape habitat corridors and a demonstration garden over the next four years. The project includes partnerships with CDFW, Yolo Basin Foundation, Center for Land-Based Learning, Putah Creek Council, the United States Department of Agriculture’s Natural Resources Conservation Service and Point Blue Conservation Science.
The demonstration garden will serve as an educational component for visitors near the wildlife area’s entrance. Two other corridors in the southern end of the wildlife area will stretch more than 5 miles total and include 22 acres of native grass seeding for nesting and cover. The corridors will run parallel to the Putah Creek channel, which is the only existing natural escape route now on the refuge.
“These corridors are basically like wildlife roads,” said Jeffrey Stoddard, the Yolo Bypass Wildlife Area manager for CDFW.
The floodwaters advance slowly enough that even the smallest animals can escape, Stoddard explained, provided they head in the right direction and don’t get exposed to predators along the way.
“We have blocks of escape habitat now, but we will be creating connectivity, moving animals from the east side that is deeper to the west side that is higher ground,” he said.
The corridors will consist of a mix of flood-tolerant native shrubs, grasses and forbs that will provide escape routes to high ground, protection from predators, food, and good habitat year-round.
The corridor work began in June with Putah Creek Council student interns collecting wild rose, red stem dogwood and coyote brush clippings for propagating and use as plant stock for the wildlife corridors.
Photos courtesy of CDFW, the Putah Creek Council and the Yolo County Resource Conservation District. Students pictured are interns from the Putah Creek Council’s One Creek Restoration Internship program.
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
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.
“We’re getting more accurate and precise numbers for harvest than we’ve ever had before, which is critical for calculating the tag quota for the next year and conserving our deer populations for the future,” said Stuart Itoga, a senior environmental scientist with CDFW and the state’s deer program coordinator.
Until recently, accurate deer harvest data had proved elusive. Prior to 2015, only successful California deer hunters had to report their take and only about 30 percent of those actually complied. CDFW supplemented the harvest data with numbers collected from game processing facilities, an inefficient process that still left an incomplete picture.
“It’s Wildlife Management 101,” Itoga said. “You have to know what your population is, what’s coming in and what’s going out. We needed to have better numbers.”
Following the mandatory reporting requirement in 2015, submittal rates for deer tag harvest reports jumped to 50 percent. In 2016, a $21.60 non-reporting penalty took effect, which applies to the purchase of future tags, and boosted reporting to the all-time high.
Mandatory deer tag reporting data is just one of a number of new tools that has CDFW deer biologists excited about their ability to better assess California’s deer herds.
An innovative DNA study of deer feces promises to give biologists new information about the size and characteristics of the state’s deer population.
CDFW has also greatly expanded the use of deer tracking collars, thanks to improved technology. Since 2016, CDFW has affixed the relatively lightweight, remotely programmable, GPS tracking devices on 350 deer to learn more about their preferred habitat, in-state and out-of-state migration routes and sources of mortality other than hunting. Advanced camera technology also promises to improve the data collected from CDFW’s aerial and ground-based population surveys. A new computer model is being developed to incorporate all of these new data sources into more sophisticated, accurate and precise deer population estimates.
“It’s really an exciting time to be doing this type of work,” Itoga said. “We’ve always used the best available science, but with technology moving at the pace it’s moving now, we have tools available to us now that we didn’t have even five years ago.”
Management changes can happen more quickly as a result. For the upcoming 2017 deer hunting seasons, for example, deer tag quotas were cut in half in three highly desirable, Eastern Sierra X Zones – X9a, X9b and X12 – as a result of new data and field work that showed that migratory deer in these areas suffered from the long, intense winter.
“Winter survival was poor,” Itoga said. “Our hope is that if we reduce the harvest this year, the populations will have a chance to rebound and increase next year.”
Kerstin Wasson is leading the Olympia oyster restoration at Elkhorn Slough. Kerstin Wasson photo.
Scientists are working hard so that a new generation of Olympia oysters may one day line the mudflats at the Elkhorn Slough Reserve.
Volunteers Ken Pollak and Celeste Stanik join Dr. Chela Zabin to improve the native oyster habitat at Elkhorn Slough. Kerstin Wasson photo.
Suspended gaper clam shells hang in aerated laboratory tanks, home to what scientists hope will be a new generation of Olympia oysters at the Elkhorn Slough Reserve.
Graduate student Dan Gossard, at CSU’s Moss Landing Marine Laboratories, shows off one of the clam shell “mobiles” on which the Olympia oyster larvae will attach when suspended in aerated tanks.
Kerstin Wasson points out Olympia oysters along the banks of the Elkhorn Slough Ecological Reserve in Monterey County.
For the first time in California history, scientists are turning to shellfish farming techniques to restore native oyster populations.
The groundbreaking research is taking place with Olympia oysters at CDFW’s Elkhorn Slough National Estuarine Research Reserve in Monterey County, in partnership with the California State University’s nearby Moss Landing Marine Laboratories and its new Center for Aquaculture.
Olympia oysters and other shellfish were once so abundant at Elkhorn Slough that Native Americans living there had multiple processing centers along the estuary’s banks to handle their harvest. Olympia oysters have disappeared altogether from many places along the California coast and their numbers at Elkhorn Slough have dwindled so low – estimated today at just a few thousand oysters – that scientists fear they may no longer be able to reproduce in the wild. Not since 2012, they say, have Elkhorn Slough’s wild oysters produced any offspring.
A combination of factors is believed to have caused the population drop over time, including poor water quality because of agricultural runoff from nearby farms and alterations to the landscape and tidal flow from generations of farming and other human activity prior to the area becoming protected in a series of conservation purchases beginning in 1971. An infusion of freshwater from last year’s rainy winter caused a severe oyster die-off and spurred biologists into action.
“This is an iconic species in our estuary in danger of disappearing,” said Kerstin Wasson, Research Coordinator at Elkhorn Slough, where she has worked for 17 years with funding from the National Oceanic and Atmospheric Administration (NOAA), the federal partner in the Elkhorn Slough Reserve. “These oysters fed native people here for 7,000 years.”
In late August, dozens of Olympia oysters were gathered and brought to the Moss Landing Marine Laboratories, where 20 spawned successfully. A few hundred thousand of their microscopic offspring are now swimming in large, circular laboratory tanks and attaching themselves to gaper clam shells suspended on fishing line from the top of the tanks. The clam shells bearing young oysters will be bound together into makeshift reefs and returned to Elkhorn Slough early in 2018 to bolster the native population.
The research is being led by a small group of scientists, including Wasson and graduate student Dan Gossard with funding provided by the Palo Alto-based Anthropocene Institute. These are uncharted waters for California scientists, however, and a major assist is coming from the aquaculture industry itself. Peter Hain of the Monterey Abalone Company has worked closely with the two researchers to set up the laboratory facility for the Olympia oysters and help with their care and feeding.
Due partly to their small size – an individual Olympia oyster is about the size of a 50-cent coin – and slow growth, Olympia oysters hold little appeal and little potential profit for most commercial oyster farmers who focus on larger Pacific varieties, many native to Japan. Taylor Shellfish Farms in Washington State is the only known commercial producer of Olympia oysters.
Wasson welcomes interest and support from aquaculture and hopes growers might one day add the native oyster to their operations. She believes even a niche commercial market for Olympia oysters could have positive implications for wild populations, enhancing recruitment, broadening scientific knowledge and a general appreciation for the native mollusk by the public.
Other efforts to save wild oyster populations in California and elsewhere have focused on building jetty-like artificial reefs constructed from oyster shell contained in plastic mesh.
Wasson prefers that more natural materials be used as part of the oyster restoration efforts underway at Elkhorn Slough, creating small clusters of oysters rising above the mudflats.
“I want this place to look like it did 200 or even 2,000 years ago,” she said.
Top photo: A huge influx of fresh water during winter 2017 resulted in an Olympia oyster die-off and spurred biologists into action.
If you’re an avid marine sport angler, you have most likely seen the smiling faces and brown polo shirts of California Recreational Fisheries Survey (CRFS) samplers. Since its inception in 2004, CRFS has grown into one of the state’s largest and most important survey efforts. Survey samplers are tasked with collecting data about both recreational fishing catch and effort.
Annually, CRFS samplers make direct contact with 68,000 fishing parties at over 400 sampling sites between the California-Oregon state line to the California-Mexico border. A separate but related telephone survey effort contacts an additional 26,000 anglers. A program of this large scale is necessary because recreational fishing effort and success rates are highly dynamic – a large sample size is needed to adequately estimate catch and effort. Recreational fishing effort is also very challenging to predict, as it can be affected by many factors (weather, gas prices, time of year, fishing seasons, etc.). But the recreational sector accounts for a significant portion of overall marine harvest, so it’s essential to collect that data to produce reliable estimates of harvest.
CRFS is part of a larger effort to estimate recreational catch and effort on the west coast and is integral to the national effort conducted by the National Marine Fisheries Service’s Marine Recreational Information Program. This partnership allows CRFS methods to be periodically peer reviewed by expert consultants throughout the country. This review provides certification that the methods meet or exceed national standards and fisheries management needs, and can recommend the use of new methods to address changing needs or to capture emerging fisheries.
There are three parts to the survey. The first is the field sampling component. This consists of in-person interviews conducted for four different fishing modes – beaches and banks, man-made structures, private/rental boats, and commercial passenger fishing vessels. Field survey questions are specific to catch and effort data during daylight hours at publicly accessible sites. The second part of the survey is the telephone survey. Anglers are randomly selected monthly through the state’s online Automated License Data System (ALDS) and asked about effort data (the number of fishing trips taken) at beach and bank sites. The telephone survey also collects data from private boats returning to sites not sampled during the field survey, and private boats returning at night. The third part of the survey is collection of data from commercial passenger fishing vessel logs. Captains submit this information for every trip, and the data is used together with field sampling data to estimate overall fishing effort.
All of this information is used in many ways. In addition to CDFW, the Fish and Game Commission and the Pacific Fishery Management Council use the data to:
How can you help? There are two ways! If you encounter a CRFS sampler in the field, please cooperate and answer the interview questions truthfully. Take the time to allow the sampler to examine and measure any catch. Recreational anglers, particularly those who fish frequently, are more likely to encounter CRFS samplers. Every fishing trip is unique — different target species, success rates, different locations, different gear, etc. — so we ask anglers, “Even if you have completed this survey before, please cooperate each time you are asked!”
Secondly, if you receive a phone call, please say “yes” to the CRFS telephone surveyor. Data collected through this telephone survey is used to estimate fishing effort that cannot be estimated any other way.
Personal contact information is always kept confidential, and the information that is collected becomes part of a public database. To learn more about the CRFS, access the database or download related flyers and brochures, please visit www.wildlife.ca.gov/Conservation/Marine/CRFS.
About 10 environmental scientists from CDFW’s Office of Spill Prevention and Response (OSPR) participated in a large-scale oil spill drill along the Feather River on March 21. The drill was intended to help wildlife response teams prepare for a potential train derailment. OSPR has a long history of oil spill response in marine environments but recently expanded its scope statewide to include inland waters. This Feather River exercise was the first time a substantial wildlife response drill has been held inland, testing responders’ abilities to resolve many operational and technical issues presented by a river spill.
Whereas marine spills typically require rescue of seabirds and occasionally marine mammals, the kinds of animals potentially affected by inland spills are quite different and varied, potentially including raptors, songbirds, reptiles, amphibians, rodents, foxes, and other mammals. The need to capture and care for these species during an oil spill presents unique challenges for scientist responders. The goal is to have the necessary protocols in place and practiced.
The drill was put on by the California Oiled Wildlife Care Network (OWCN), an organization funded by OSPR and managed by the UC Davis School of Veterinary Medicine to provide best achievable care of oiled wildlife. The OWCN currently maintains a network of 40 wildlife rehabilitation organizations, trained and ready to respond to oil spills anywhere in the state. Sixteen of these organizations participated in Tuesday’s drill, including two local organizations, Shasta Wildlife Rescue and Rehabilitation and North Valley Animal Disaster Group.
In addition to practicing wildlife response activities, the drill provided the opportunity to test a new Geographic Response Plan (GRP) for the Feather River. GRPs identify the location and nature of resources at risk in the event of a spill, and outline appropriate tactical response strategies to minimize oiling and other injury. During a real spill, OSPR environmental scientists serve as subject-matter experts who help ensure that the GRP is implemented appropriately. A simulated situation like this one gives them a valuable opportunity to conduct a realistic ‘dry run,’ as well as to analyze elements of the GRP and make adjustments as necessary.
To learn more about OSPR, visit www.wildlife.ca.gov/OSPR.
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