Recent accomplishments of CDFW's scientific community
A California red-legged frog sits motionless at the edge of McClure pond at the Sparling Ranch Conservation Bank. Photo by Ashley Spratt/USFWS
McClure pond is one of the most productive California red-legged frog ponds at the Sparling Ranch Conservation Bank. Like many of those on Sparling Ranch, it was named after the family who homesteaded in site in the late 1800s. Photo by Ashley Spratt/USFWS
Since the mid-1980s, California has been using a system of conservation and mitigation banking to protect valuable natural resources and critical habitat for fish, wildlife and plants. These banks are generally large, connected, ecologically meaningful areas of preserved, restored, enhanced or constructed habitat (for example, wetlands) that are set aside for the express purpose of providing mitigation for project impacts. Conservation banks provide mitigation for impacts to listed species and habitats, while wetland mitigation banks primarily provide mitigation for wetland impacts. Together, they serve to prevent inadequate, fragmented reserves that can result when mitigation projects are carried out individually.
Banks work by establishing credits for sensitive species or habitats found on a given site. These credits can then be sold to developers or other project proponents who need to meet permitting requirements or are otherwise required to compensate for environmental impacts. For those parties needing to mitigate for project impacts, banks serve to streamline the regulatory process by providing a pre-established mitigation site that the regulating state and federal agencies have already confirmed will provide adequate and appropriate mitigation for certain habitats or species. By mitigating at a bank, project proponents can avoid the time and cost of searching for a suitable mitigation site and protecting it in perpetuity themselves.
In order for the banking system to be effective, state and federal agencies must work closely together to align processes and practices. Since 1993, CDFW has been participating in the planning, review, approval, establishment, monitoring and oversight of 81 banks statewide. Other agencies that typically participate in the regulation and approval of conservation banks include the U.S. Army Corps of Engineers (USACE), U.S. Environmental Protection Agency (USEPA), Natural Resources Conservation Service (NRCS), U.S. Fish and Wildlife Service (USFWS) and the National Oceanic and Atmospheric Administration National Marine Fisheries Service (NOAA NMFS).
To read more about one of these successful partnerships, please visit USFWS’ newsroom.
Learn more about CDFW’s Conservation and Mitigation Banking program, on our website.
All photos courtesy of U.S. Fish and Wildlife Service.
Top photo: A herd of cattle graze atop a hillside at Sparling Ranch near Hollister, Calif. Photo by Ashley Spratt/USFWS.
Surveying Ventura River in Ventura County
Snorkel survey in Hollow Tree Creek in Mendocino County
Hollow Tree Creek steelhead
Taking care of California’s fish and wildlife wouldn’t be possible without managing the resources upon which they depend. To that end, CDFW has an entire branch – and many scientific staff – dedicated to the scientific study, and planning and management of water resources.
Within the Water Branch, CDFW’s Instream Flow Program (IFP) is tasked with collecting and contributing data necessary to make all kinds of important management decisions about ecological function, fish rearing, spawning and migration and habitat suitability.
In the simplest terms, “instream flow” refers to the rate of the water running through a waterway in a natural environment. But when one considers all the interests competing for use of that water – fisherman, boaters, farmers, businesses, water districts, and fish and wildlife themselves – the complexity of the subject is evident.
Measured in cubic feet per second (cfs), instream flow can be measured at different times of the year in a specific location in a waterway. The fluctuations can tell scientists quite a bit about the ecosystem health of a watershed. While some watersheds have flowing water throughout the year and others are intermittent it is often the responsibility of water managers to distribute the water between uses. CDFW, a natural resource management agency, is faced with the complex task of identifying and recommending instream flows necessary for supporting natural resources. Determining instream flows are crucial so that aquatic, riparian, and terrestrial resources dependent on water will be considered and protected during water distribution activities.
Guided by the California Water Action Plan, the Public Resources Code and the Fish and Game Code, IFP staff conduct flow studies, collect field data, develop guidelines for quality assurance, conduct outreach and coordinate with other agencies and interested parties on program-related activities.
In the past year, some of IFP staff’s largest projects have included:
To learn more about these specific projects, please download the IFP’s 2017 Year in Review (PDF) document, available on CDFW’s website.
A Featured Scientist Q&A with the IFP manager Robert Holmes is also available on the CDFW Science Institute page.
CDFW photos. Top photo: IFP staff hold a planning meeting prior to a survey on the Ventura River in Ventura County
California’s coastal waters are home to seven species of abalone, and all but one are endangered or listed as species of special concern. The white abalone in particular has been nearly decimated by overfishing and disease, and scientists can find no evidence that the remaining population is reproducing in the wild. In order to avoid loss of the entire species, CDFW and partner agencies have formed the White Abalone Recovery Consortium, which will employ captive rearing and restoration stocking efforts and extensive public outreach in order to save these animals from extinction. It will be an ongoing, long-term project, but all signs point to future success – already there are more white abalone thriving in the captive breeding program than the entire population living in the wild.
Read more about the efforts to restore California’s white abalone – and learn what you can do to help! – on the CDFW Marine Management News Blog.
“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.
Working late, Mojave River hatchery staff apply FDA-certified epoxy coating to hatchery rearing ponds.
CDFW fish transportation truck at Fillmore Hatchery
Acting Mojave River Hatchery Manager Forest Williams at work
A hatchery crew releases trout into the Feather River
A fishy view of trout planting on the Feather River
The beginning of trout fishing season in Southern California is just around the corner, and CDFW biologists and hatchery staff are striving to maximize hatchery trout availability for the many anglers who will cast lines in coming weeks. Trout angling in lower-elevation waters of Southern California generally begins in November and continues through April, to correspond with colder water temperatures that can sustain stocked trout.
Precise temperatures are just one of the criteria that must be met before trout stocking begins. Currently, these conditions are approaching optimal levels, but CDFW is running about two weeks behind schedule due to unforeseen circumstances at Mojave River and Fillmore trout hatcheries, two of CDFW’s southernmost facilities.
The Mojave River Hatchery, built in 1947, raises and stocks a ten-year average of 340,000 pounds of catchable trout per year. Beginning in June of this year, extensive maintenance and facility upgrades necessitated turning off the water for a six-month period. While the completed upgrades will ultimately result in better and more efficient trout production for Southern California, the project ran about two months behind schedule. Water is scheduled to flow again at Mojave River Hatchery in late November and the hatchery will be populated with fingerling trout for fast growth. Mojave’s year-round water temperatures yield fast trout growth resulting in maximized yield in minimal time.
While the Mojave River Hatchery was closed, Fillmore Hatchery, built in 1941 on the Santa Clara River, experienced a significant loss of trout inventory intended for Southern California angling due to gas bubble disease. Gas bubble disease is a result of supersaturated gasses (oxygen, nitrogen and carbon dioxide) present in well water pumped from a deep aquifer. While Fillmore Hatchery is equipped to aerate this water and make it suitable for trout, an unknown variable (possibly a drought-depleted and then recharged aquifer) overwhelmed that ability. In an average year, Fillmore Hatchery produces about 400,000 trout for lakes and streams in Southern California. To reduce fish losses from gas bubble disease in the last several weeks, catchable fish were stocked from Fillmore to appropriate waters, and some fish were transferred to other hatcheries. Ultimately, the gas bubble disease at Fillmore resulted in a loss of about 50 percent of inventory. While emergency measures taken by Fillmore staff and
CDFW fish pathologists resulted in better conditions and lower gas super-saturation, the hatchery must be depopulated so that the issue can be addressed entirely. As soon as all trout are removed, hatchery staff and scientists will increase the gas diffusion capability of aeration towers at Fillmore, in order to handle supersaturated well water for the short and long term.
The status of these two hatcheries presented a substantial problem for trout stocking in Southern California that was solved in part by hatcheries in Central and Northern California. These hatcheries have sufficient catchable size trout to supply Southern California’s approved waters immediately and in coming weeks. Thanks to strategic planning and trout production at a statewide level, Northern and Central California can supply fish to Southern California without impacting originally scheduled trout releases in their respective areas.
Trout stocking for Southern California waters will begin this week and hatchery trucks are on the move. Hatchery staff will work quickly to distribute trout to as many approved waters as possible. Trout stocking to Southern California will initially be lighter than usual, but will likely pick back up in 2018. As Mojave River Hatchery comes back online, fish transferred to that facility will be fed and reared to maximize daily growth. We anticipate another large batch of catchable trout available for Southern California toward early spring 2018.
Hatchery staff will be doing everything possible, statewide, to maximize trout production and releases to approved waters in the coming months. Staff work diligently for the angling public and appreciate their continued support.
The statewide planting schedule is updated in real time online.
CDFW photos. Top: Steelhead trout at Mokelumne River Hatchery
California’s recreational fishery resource provides a huge benefit to the state’s economy. In the latest issue (102-3) of the scientific journal California Fish and Game, Reid et. al tackles the difficult task of quantifying the economic value of California’s recreational red abalone (Haliotis rufescens) fishery.
Using data for the 2013 season at more than 50 sites in Sonoma and Mendocino counties, the authors used the travel-cost estimation method to determine a value. According to their findings, the 31,000 people who fish for red abalone provide an economic benefit to California of between $24M and $44M annually.
The lower figure was derived solely by determining the costs involved in driving to the fishing locations, while the higher figure considers the time spent on the fishing activity. The data reveal three dominant criteria used to select fishing sites: 1) the presence of a harmful algal bloom — and the resulting stricter fishing regulations — in Sonoma County; 2) protection from ocean swells; and 3) the presence of recreational conveniences such as restrooms and boat launches.
Determining the economic value of the red abalone fishery puts into perspective the importance of managing it for sustainability.
Other articles in this issue focus on management implications for California halibut (Paralichthys californicus) and Olympia oysters (Ostrea lurida).
Lesyna and Barnes report that California halibut reach physical maturity at different sizes and ages, depending upon location. Macroscopic examination of specimens revealed that, although all halibut were mature before reaching the commercial and recreational minimum legal size limit, central California halibut are larger and older by the time they reach physical maturity than their southern California counterparts.
Moore et. al studied the sexual development and symbionts of Olympia oysters (Ostrea lurida) that settled naturally on artificial clutches placed in San Francisco Bay. The results of the study suggest that Olympia oysters have the capacity to flourish when suitable habitat is available.
Collectively, these articles demonstrate the importance of studying natural resources for their consumptive and non-consumptive value.
According to California Fish and Game Editor-in-Chief Armand Gonzales, the articles provide critical direction for resource management. “It is therefore incumbent upon us as scientists, to keep working, keep studying and keep reporting what we see and find.
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