Science Spotlight

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  • February 7, 2019

Flocks of sea birds flying above large bay with boats, bridge, and hills in distant background
Circling birds indicate an offshore herring spawning event near Alameda.

Hundreds of sea birds floating on water with docks and homes on hills in background.
Bird activity after a spawning event.

Long, green aquatic plant material covered in thousands of tiny clear balls.
Heavy spawn on eelgrass.

On a drizzly winter day in San Francisco Bay, you might find CDFW Environmental Scientist Ryan Bartling surveying the shoreline on the research vessel Smoothhound in search of Pacific Herring (Clupea pallasii) eggs. Bartling is one member of a team of state biologists who monitor the San Francisco Bay Herring fishery in the winter months, counting eggs and using those numbers to estimate the size of the Herring population that enters the Bay each season. CDFW Environmental Scientists Tom Greiner and Andrew Weltz are the other members of the Herring Team who lead the collection of biological data and management of commercial take of Herring in San Francisco Bay.

“We see, on average, about 50,000 tons of Herring come into San Francisco Bay during the spawn events that occur about 12 times each year,” Bartling explains. “The fish typically show up from November through March, so that’s when we’re out there counting eggs and collecting biological information on adult Herring.”

Even before the spawning season starts, Bartling and Weltz, with assistance from other CDFW divers, perform SCUBA surveys in the Bay to estimate how much vegetation is present. In-season, Greiner runs weekly trawl surveys, using the 28-foot research vessel Triakis to catch adult Herring before they spawn. This catch provides information on size, weight and age of the adult herring, it also provides information on general health and condition.

Once the spawning begins, the biologists concentrate on spawn deposition surveys – which involves finding and counting egg masses wherever the fish lay them. Eelgrass (Zostera marina) and red algae (Gracilaria species) are common vegetation types for spawning Herring, but the fish will also gravitate to hard surfaces or man-made structures near the shoreline – pier pilings, boat bottoms and even submerged shopping carts, anything in the vicinity of a spawn is fair game. Although the eggs are tiny (about the size of the tip of a pencil), they’re laid in mass.

How do the biologists know where to look? There’s a dead giveaway. “The key indicators are the birds and marine mammals – they always find them first!” Bartling says. Using the circling birds as his guide, Bartling walks along the shoreline at low tide to do a visual count of eggs, or, if aboard the Smoothhound, he uses a rake to pull up vegetation from below.

When a spawning event is occurring, the actual survey time varies. CDFW scientists could be counting eggs for as little as four hours, or as long as 12 hours at a time depending on the size of the Herring school. Using the egg count numbers (which are typically in the billions or trillions), they can calculate estimates of Herring tonnage. “An estimate could be as small as one ton of Herring per spawn event up, or might be as high as 15,000 tons,” Bartling says. “It depends on time of year and the overall stock size.”

The estimates are necessary for CDFW to set quotas for California’s commercial Herring fishery, which runs from January through mid-March. Quotas are typically set at around 5 percent of the total tonnage the biologists calculated from the previous season.

CDFW Herring fishery management staff maintain a blog, link opens in new windowCDFW Pacific Herring Management News, to keep the public apprised of the health and status of the fishery. More information about the commercial Pacific Herring fishery can be found on CDFW’s website.

CDFW Photos. Top Photo: CDFW Environmental Scientist Ryan Bartling looks at herring eggs after a spawning event.

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Media Contact:
Kirsten Macintyre, CDFW Communications, (916) 322-8988

Categories: Wildlife Research
  • January 24, 2019

Owl in flightShort Eared Owl. Courtesy of the National Digital Library.

Owl on snowy groundShort Eared Owl. Courtesy of the National Digital Library.

Owl perched on wooden fence post for barbed wire fence.Short Eared Owl. Courtesy of the National Digital Library.

Owl on snow-covered ground with low bush in foregroundShort Eared Owl. Courtesy of the National Digital Library.

A team of raptor biologists is working on a study of western populations of the Short-eared Owl – and are inviting members of the public to help collect and contribute important data as “citizen scientists.”

The project, known as the Western Asio Flammeus Landscape Study (WAfLS), is being conducted across eight western states, including Idaho, Montana, Nevada, Oregon, Utah, Washington and Wyoming, in addition to California. The purpose of the study is to determine the reasons for the sharp decline in Short-eared Owl populations – more than 60 percent over the last four decades across their western range.

“This project is a really unique and exciting collaborative effort to understand the species population on a very large scale,” said Carie Battistone, CDFW’s raptor biologist and WAfLS’ California State Volunteer Coordinator. “Given how wide-ranging – and in some cases, remote – the owls’ habitat is, we rely heavily on volunteers to help us collect the data we need.”

Battistone added that no special knowledge of raptors is needed in order for individuals to participate and contribute. “You don’t need to be a bird expert. You just need to have a keen interest in the outdoors and for the wildlife species that call California home,” she said.

The WAfLS project identifies 54 survey routes in California, all located within known habitat of the Short-eared Owl. “Citizen scientist” volunteers are needed to drive these routes, stop every ½ mile to look for and record owl presence and habitat features at each point. Volunteers will be asked to conduct two separate surveys on days of their choice during specified three-week survey windows in March through May. Each survey takes about 90 minutes and must be conducted during specified twilight hours, when the owls typically conduct their elaborate courtship displays.

Survey grids are located throughout much of the state from Modoc County in the north, Humboldt County in the west, Santa Barbara and Kern counties in the south and Mono County in the east. To view a map showing the grids for which volunteers are still needed, please visit the WAfLS website and click on “sign-up” on the right. The website also has a wealth of information on the project’s goals, as well as past reports, maps and volunteer resources (protocol, data sheets, etc.).

Battistone said that the information gathered by citizen scientists will be used by conservation experts and managers to design and implement strategies to help bolster populations of the Short-eared Owl.

“The project will help to determine what the Short-eared population numbers are like across the west, quantify how populations fluctuate spatially and temporally and identify how various factors – such as distribution, farming practices, grazing and climate – influence owls,” she said. “Once we have the data and resulting analyses in hand, we can make informed decisions on how to best protect and conserve the species.”

Owl photos courtesy of the National Digital Library. Top Photo: SEOW Survey: Surveying for Short-eared Owls can be a fun family activity. (CDFW Photo by Carrie Battistone.)

Media contact:
Kirsten Macintyre, CDFW Communications, (916) 322-8988

Categories: Wildlife Research
  • December 14, 2018

Brown haired woman wearing glasses, white laboratory coat and white gloves in front of machine in laboratory
Kelly McCulloh loads evidence samples onto a DNA extraction robot.

Brown haired woman in white laboratory coat and white gloves holding pipette standing at counter in laboratory
Jillian Adkins prepares samples for DNA extraction.

Brown haired woman in white laboratory coat and white gloves sitting at desk with microscope and small tool in hand.
Erin Meredith uses a dissecting microscope to isolate hair roots for nuclear DNA extraction.

Long haired woman in white laboratory coat and blue gloves standing at laboratory machine with glass window partially lowered.
Ashley Spicer prepares a Polymerase chain reaction used in DNA sequencing.

If they weren’t so busy or their work wasn’t so mission-critical, you might find CDFW’s Wildlife Forensics Laboratory team on loan to the California Department of Education.

The four-person scientific team is all women with undergraduate and advanced degrees in biochemistry, genetics, molecular biology and forensic science.

Jillian Adkins, Kelly McCulloh, Erin Meredith and Ashley Spicer would be stars of state education initiatives to attract more girls to STEM (Science, Technology, Engineering and Mathematics) fields. They would be celebrated at school tours, asked to provide their personal stories at education conferences and inspirational messages in science classrooms across the state.

Instead, this team works mostly out of the spotlight, their scientific analysis critical to CDFW’s law enforcement mission to protect California’s natural resources and provide public safety. Increasingly, CDFW’s Wildlife Forensics Laboratory is being counted on to protect some of the most sensitive animal species on the planet.

“We just don’t lose these cases supported by forensic evidence. It’s amazing,” said Tony Warrington, a recently retired assistant chief who has managed CDFW’s crime lab for more than a decade. “Our forensic specialists do a fantastic job utilizing advanced scientific methods to support wildlife officers with poaching investigations and public safety wildlife incidents.”

Meredith, a senior wildlife forensic specialist with nearly 20 years at the lab, said the mere suggestion by a wildlife officer of sending evidence in for DNA analysis will sometimes prompt poachers to confess to their crimes. The lab is one of only about 10 wildlife forensic labs in the nation, giving CDFW wildlife officers a major crime-fighting assist. Every CDFW wildlife officer can access the lab, which processes evidence in about 100 criminal cases every year.

The white lab coats, antiseptic setting, high-tech equipment and talk of DNA sequencing invite comparisons to “CSI” – Crime Scene Investigations – the long-running night-time television drama that firmly implanted forensics in the public consciousness.

“My joke is always that human forensics is boring – you only work on one species,” Meredith said. “With wildlife, the possibilities are essentially endless.”

First established in the 1970s, CDFW’s Wildlife Forensics Laboratory has taken on a more prominent role with advances in genetic research and technology and the widespread acceptance of forensic evidence in the court system.

“If there’s blood on a knife, not only can we tell whether it’s from a deer, we can also tell whether it’s from a doe or a buck,” Meredith said. “We can tell if the blood on the knife originated from the same deer or evidence taken from a kill site or meat in a suspect’s freezer.”

Said Adkins, “DNA evidence has been a game-changer in determining guilt or innocence – in both people and wildlife.” Adkins’ work in providing quick turnaround of DNA samples allows wildlife officers to use the results to make critical enforcement decisions.

CDFW’s Wildlife Forensics Lab plays a key role in public safety and animal attacks that may involve great white sharks, coyotes, bears or mountain lions. With even minimal DNA evidence, offending species and animals can be identified with certainty in most instances.

“We literally free the innocent – and it’s happened a number of times,” Meredith said. “Our wildlife officers may trap what they think is the guilty bear, draw its blood and bring it to the lab for comparison with saliva from a bite wound or even a scratch mark on the victim. And if that DNA is not a match, that bear gets released.”

Retired assistant chief Warrington said, “This lab completely changed the way we deal with public safety wildlife. DNA matching has allowed CDFW to protect the innocent and positively identify the offending animal in these cases – a big step forward in protecting California’s wildlife.”

The lab marked another milestone in 2015 with the adoption of Assembly Bill 96, which closed a loophole in the state’s ban on ivory and made it illegal to purchase, sell, possess with intent to sell or import with intent to sell ivory or rhinoceros horn – with limited exceptions.

The legislation tasked a state wildlife agency with helping to combat the global ivory trade in order to protect ivory bearing species from poaching, exploitation and extinction worldwide. AB 96 provided funding for CDFW’s Wildlife Forensics Lab to add a fourth scientist in McCulloh.

McCulloh arrived with a master’s degree in forensic science from UC Davis. She has pioneered California’s genetics test for ivory products. It’s so accurate, it can distinguish African elephant ivory from Asian elephant ivory and even ivory from a long-extinct woolly mammoth.

Spicer, a native of British Columbia with degrees in biochemistry and forensic science, specializes in the physical characteristics of ivory that distinguish it among the many different ivory-bearing species – from elephant and hippopotamus to sperm whale and warthog – and also from non-ivory products such as synthetic ivory or plastics made to look like ivory. 
Spicer personally has worked on 17 of the 18 criminal ivory cases that have come through the lab since AB 96 was enacted. Her work has included serving as an expert witness and testifying at trial.

The lab’s contributions were link opens in new tab or windowheralded recently in the conviction of a Los Angeles County business owner on charges of selling two ivory tusks from Arctic narwhal whales. The tusks measured 79 and 89 inches long.

CDFW’s forensic scientists don’t necessarily mind all the newfound recognition – as long as the focus remains on their work.

Said Spicer, “We are really committed to the highest standards and ideals of science.”

YouTube Video Link: link opens in new tab or windowhttps://youtu.be/4KS4e3ILKOw

CDFW Photos. Top Photo: The four-woman forensics team.

Categories: Wildlife Research
  • October 26, 2018

Several people wearing waders in streambed holding nets in water
CDFW staff and volunteers set a one-day record of 1.5 million eggs collected on the Little Truckee River earlier this month.

People holding white net in water with several kokanee salmon in net
CDFW staff and volunteers use seine nets and electric fishing techniques to corral and capture adult Kokanee salmon.

Several people wearing waders holding nets in streambed. Boat and trees in background.
Volunteers from the California Inland Fisheries Foundation, Inc. and Kokanee Power help CDFW personnel capture Kokanee salmon.

Each October, conditions permitting, CDFW staff and volunteers from the California Inland Fisheries Foundation, Inc. and Kokanee Power descend on the Little Truckee River, just upstream from Stampede Reservoir near Truckee, and get to work on the annual Kokanee Egg Take.

Using seine nets and electrofishing techniques to corral and capture adult Kokanee Salmon, staff and volunteers then collect eggs and milt (fish semen) add them together in specific ratios to complete the spawning process. The fertilized eggs are carried to an egg care station on the side of river where they are measured, enumerated, disinfected and finally placed in containers to be transferred to the San Joaquin Hatchery.

Staff at San Joaquin Hatchery incubate, hatch and care for the early-life stages of the resulting baby salmon. Some fertilized eggs are shipped to other CFDW hatcheries for hatching and rearing. Resulting fingerling fish are stocked to several approved waters in the state to provide recreational angling opportunities.

“By all accounts, this year set the one-day egg take record of 1.5 million eggs,” said Roger Bloom, CDFW’s Inland Fisheries Program Manager. “This was a collective effort from our scientists, hatchery staff and stakeholders that culminated into actions in support of fisheries across the state. Given the magnitude of eggs taken on that record day, it took a non-stop effort of over 23 straight hours to get the job done, which highlights the dedication and resolve CDFW personnel have -- especially the hatchery staff who now will care for these eggs that will eventually grow to be little salmon!”

Kokanee Salmon were introduced into California waters to provide diverse recreational angling opportunities for anglers and have become an extremely popular sport fish. They are typically smaller than the landlocked Chinook Salmon, with an average size of about 12 inches. This summer, CDFW will release the Kokanee Salmon fingerlings that emerge from this collection effort into lakes and reservoirs throughout the state.

The landlocked version of the Sockeye Salmon, the Kokanee (pronounced coke-a-nee) Salmon spends its entire life in fresh water. Instead of migrating to the ocean, adult Kokanee Salmon inhabit large lakes before returning to their natal streams or gravelly shorelines to spawn. Like all Pacific salmon, Kokanee die after spawning, the whole life cycle taking from two to four years.

CDFW Photos. Top Photo: Volunteer holds a Kokanee salmon during work on the Little Truckee River.

Categories: Wildlife Research
  • October 19, 2018

Closeup shot of salmon fin
Close-up of adult spring-run Chinook salmon dorsal fin.

Close up shot of salmon with mouth open wide while held in hand
Adult spring-run Chinook salmon inform river restoration decisions by their habitat use and preferences.

Man wearing khaki colored waders, grey short sleeve shirt, orange vest and green CDFW baseball cap standing in water bent over holding salmon. Two other people standing in background.
Adult spring-run salmon are carefully selected for release based on their sexual maturity.

Salmon with blue tracking device held above white net over water
Spring-run Chinook salmon released into the San Joaquin River are outfitted with three tags including a colored T-bar tag for visual identification.

Fresno County may seem an unlikely setting for salmon restoration and research, but some of the California Department of Fish and Wildlife’s (CDFW) most ambitious work with salmon anywhere is taking place in the heart of the parched Central Valley.

Since September, CDFW fisheries biologists have been spawning spring-run Chinook Salmon broodstock in the shadow of Friant Dam on the San Joaquin River. This season, CDFW staffers spawned 100 mature females that ranged in age from 3 to 6 years old  producing about 290,000 eggs.

It’s all part of an unprecedented, multiagency effort to restore an extinct, spring-run Chinook Salmon run to the San Joaquin River that is happening alongside river restoration efforts to make the river more salmon-friendly for a fish listed as threatened under both the state and federal Endangered Species Act.

Historically, spring-run Chinook Salmon were the most abundant salmon species in the Central Valley. Today, there are so few fish broodstock used for spawning comes from eggs collected at CDFW’s Feather River Hatchery in northern California. Meanwhile, construction is underway on a spring-run Chinook Salmon hatchery at the base of Friant Dam to support future runs of San Joaquin River salmon. The hatchery is scheduled to be completed in 2019.

During spawning, each female is crossed with four males to maximize genetic diversity. Samples of ovarian fluid are collected and sent to the CDFW’s Fish Health Lab for virology and bacterial analyses. Any egg lots determined to be potentially infected with pathogens are excluded from CDFW’s captive rearing program.

In June and August, 179 captive-reared adult fish – 59 females and 120 males – were released into the San Joaquin River to monitor what parts of the river the salmon prefer for holding and natural spawning.

Prior to release, each fish was outfitted with three tracking devices – an electronic passive integrated transponder (PIT) tag for individual identification, a colored, T-bar tag for visual identification, and an acoustic transmitter so their movements in the river can be monitored and recorded. Their habitat use and preferences inform river restoration efforts.

Spring-run Chinook Salmon spawn in the fall from mid-August through early October. So far, biologists have found 37 constructed redds – or salmon nests – in the San Joaquin River indicating some of the released salmon found enough cool water in the heavily damned and diverted river system to survive the Central Valley’s furnace-like summer and are now actively spawning in the river.

CDFW Photos by Travis VanZant. Top Photo: Prior to their release into the San Joaquin River this past summer, adult spring-run Chinook salmon were outfitted with acoustic transmitters so their movements in the river can be monitored and recorded.

Categories: Wildlife Research
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