Science Spotlight

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  • 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
  • January 18, 2019

Four men and large fishing nets on small fishing boat on water. Marina and levy in background.
Joe Millosovich, an environmental scientist who specializes in lake and fisheries management in the Central Valley, came all the way from Fresno to captain one of the electrofishing boats collecting bass in the Delta Jan. 16. Several of CDFW’s biologists participating in the outing called it one of their favorite days of the year.

Man wearing gray camo foul weather gear, backward ball cap, and black life vest with yellow reflectors behind helm on fishing boat on water. Cloudy skies and grass-covered levy in background
Max Fish, an environmental scientist with CDFW’s Inland Fisheries Program, captained the electrofishing boat that collected the largest largemouth bass of the morning – a 10-pound-plus whopper.

Man wearing blue foul weather gear, blue ball cap, on docked fishing boat holding up two large fish. Water, land, and trees in background.
Kyle Murphy, a senior environmental scientist with CDFW’s Inland Fisheries Program, shows off two of the larger Delta largemouth bass headed for the International Sportsmen’s Exposition demonstration tank in Sacramento.

Among the more popular attractions at the Sacramento International Sportsmen’s Expo each January is the Western Bass Aquarium Demo Tank. The 6,000-gallon aquarium displays dozens of trophy largemouth bass collected by CDFW biologists from the Sacramento-San Joaquin Delta. The aquarium demo tank, with bleachers on both sides, is where professional bass anglers lead seminars demonstrating the latest techniques and can’t-miss lures – all without hooks attached so as not to injure the fish.

“This is the best display of largemouth bass anywhere in the country,” said Kent Brown, the longtime host of the ISE demonstration tank. “And that’s not just me talking. That’s from tournament bass fishermen who travel all over the country. There’s just no bass anywhere that can rival these Delta bass.”

The tank is also a tremendous source of pride for the CDFW fisheries biologists tasked with collecting the fish.

“It’s great for people to see the kind of fish they can catch here in their own backyard,” says Ben Ewing, a CDFW district fisheries biologist who headed the ISE collection effort this year. “All the fish get released back into the Delta immediately after the show and literally are available for anyone with a fishing license to catch.”

A mix of 16 fisheries biologists and volunteers assembled along the Delta near Stockton the morning of Jan. 16, the day before the opening of the four-day ISE show at Sacramento’s Cal Expo. They climbed onto four electrofishing boats to probe likely largemouth hideouts – tule stands, rip-rap shoreline, sunken boats, submerged tree limbs and other structure.

“We all come together to try and make a good display for the public,” Ewing said.

Over the years, a friendly competition has developed. A trophy and bragging rights go to the CDFW boat captain who collects the largest bass for the show. Each of the four captains took off with their crews in different directions searching for a largemouth bass that might not only win the day but one that might top their all-time ISE show record fish of more than 13 pounds.

The boats sent targeted currents of electricity through the water while crew members standing on the bow were ready with nets to scoop up the stunned fish for deposit into the live wells for safekeeping. In more than 20 years of providing Delta largemouth bass for the Sacramento ISE show, CDFW biologists have refined their methods and strategies.

In addition to looking for the largest fish, a mix of sizes is collected. Smaller bass add perspective in the tank and make the biggest fish look even bigger. Suckers, catfish and large sunfish add some fun diversity to the display. Striped bass are a no-go – they don’t do so well in transport and they’ve been known to jump out of the aquarium.

Max Fish, an environmental scientist with CDFW’s Inland Fisheries Program, piloted one of the electrofishing boats. He explained how these vessels are important research tools that allows CDFW scientists to survey fish populations and assess health in the state’s lakes and reservoirs. CDFW puts one of the boats on display at the ISE show each year and points out the connection between the boat and the bass in the tank.

On that overcast January morning with major winter storms looming in the forecast, Fish sent 340 volts of electric current through the shallow Delta waters. The conditions for electrofishing were nearly ideal – the plentiful organic material in the Delta helps conduct electricity while the overcast skies were unlikely to spook fish and send them deep beyond the boat’s effective reach.

Fish said the boat’s electric current ranges about 10 feet deep and about 20 feet wide – roughly the span between the two sets of anodes extending from the boat’s bow into the water.

Fish’s efforts were rewarded with the largest bass of the day – a 10.3-pound lunker among others in the 9- and 8-pound class. After congratulations, photos and good-natured ribbing from his colleagues back at the dock, the 60 or so fish collected by all the boats were shuttled directly to Sacramento’s ISE show in an aerated live well.

Meeting them there was CDFW veterinarian and fish pathologist Keven Kwak, who tested and treated the aquarium’s water to make sure it was safe for what would be the fish’s short, but celebrated stay in Sacramento.

CDFW Photos. Top Photo: CDFW biologists stand ready with nets in hand to scoop up temporarily stunned fish for the ISE’s bass fishing demonstration tank in Sacramento. Biologists look for the biggest and best specimens to showcase the Delta fishery. While the biologists are targeting largemouth bass primarily, the electric current brings up carp, catfish, suckers, striped bass and all manner of sunfish. Within a minute or two, the stunned fish come to and swim off.

Media Contact:
Peter Tira, CDFW Communications, (916) 322-8908

Categories: General
  • December 19, 2018

Large pile of old christmas trees on dirt with live tree forest in background.

Two men wearing hats and life vests aboard small boat on body of water piled with old christmas trees. Some trees are submerged in water body. Live tree forest in background.

Boat on water body dragging small boat with two men and pile of dead christmas trees. Live tree forest in background.

Two men wearing life jackets aboard small boat on body of water with pile of dead christmas trees. Forest and mountain in background

Christmas can be the gift that keeps giving -- to anglers and fish alike.

In the north state, CDFW fish habitat technicians oversee the collection of discarded Christmas trees, which will be used to build underwater habitat structures for local waterways. Long after they’ve brightened holiday homes, these trees will provide shelter for juvenile warmwater fish species -- and ultimately will create better fishing opportunities for anglers.

According to Joseph Rightmier, a fish habitat supervisor with CDFW’s Fish Habitat Improvement Shop in Yreka, the trees are weighed down with cables and submerged, creating a refuge for juvenile fish, including Largemouth Bass and crappie.

“The fish get into the voids within the structure, which gives them some protection. And when you attract smaller fish, you also end up attracting larger, catchable fish, which hang out close to the surface and wait for a meal,” Rightmier said.

“Divers have determined that fish start congregating in and around the structures within a day or two of the habitat structures being installed. They’re hot real estate in the water!”

One of the largest efforts to collect and “upcycle” trees is conducted by Rightmier’s team in Siskiyou County. Last summer, staff used trees collected after the 2017 holidays to create and then place 22 habitat structures into Green Springs Reservoir in Modoc County. The habitat structures were comprised of approximately 200 recycled Christmas trees and small junipers. The Christmas trees were collected at drop-off locations in the cities of Alturas and Yreka, and the small junipers were harvested in the Modoc National Forest.

In 2018, Rightmier said, the Yreka fisheries habitat technicians also used trees to build fish habitat structures in three other locations: Juanita Lake, Orr Lake and Trout Lake. Similar projects have also been conducted at Lake Shastina and Dorris reservoir in the past.

Further south, CDFW’s Redding office is also overseeing a Christmas tree collection operation. The tentative collection location will be in the town of Chester, and the trees will be used for a project in Lassen County.

“Generally, we prefer hardwoods when doing habitat projects, but we do use Christmas trees when they’re available,” explained Monty Currier, an environmental scientist with CDFW’s Reservoir Program. “The trees would go a landfill to be chipped otherwise, and we believe that recycling is a better idea. And people are happy to help CDFW with this kind of habitat improvement project – who doesn’t like the idea of making our fisheries better?”

Currier is currently working with a local bass fishing group and county officials to determine a specific tree dropoff point.

Donated trees should not be flocked, and should be stripped of lights, tinsel and ornaments. The trees are usually transformed for their new use within a couple of months, before they dry out completely.

“Our fish habitat shops enjoy doing this type of project, and it makes a real difference in how successful anglers are,” Currier says. “Everybody wins – not just the fish!”

###

Interested in recycling your Christmas tree in Siskiyou, Plumas or Modoc counties? Drop-off locations for Christmas trees will be located near the CDFW offices in Alturas (702 East Eighth St.) and Yreka (at the corner of Ranch and Oregon streets, due west of the CDFW yard). In Chester, the location has not yet been determined, but you can call the main office at (530) 225-2300 for information closer to the holiday.

CDFW Photos. All Photos: Fisheries biologists placing recycled Christmas trees into Mountain Meadows Reservoir, Lassen County, to create habitat for juvenile fish.

Categories: General
  • 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
  • November 2, 2018

California Fish and Game, Volume 104, Issue 2, is now available online! California Fish and Game is CDFW's official, quarterly, scientific journal devoted to the conservation and understanding of the flora and fauna of California and surrounding areas, and the eastern Pacific Ocean.

A mallard in flight appears on the cover of the newest installment of the journal. With its iridescent green head and school bus yellow legs, the male mallard is one of the most recognizable species of duck in California. It is also the most abundant breeding species of waterfowl in the state. However, California’s mallard population estimates have generally declined since the mid-1990s. In California mallards: a review, Feldheim et. al synthesizes volumes of research in an effort to identify long-term research needs and monitoring activities to help improve management of this iconic species.

In another paper, entitled Abundance, habitat and occupancy of Roosevelt Elk in the Bald Hills of Redwood National Park, Tolliver and Weckerly seek to understand the relationship between a species’ occupancy-abundance rate and its habitat use. Using elk sign surveys (i.e, counting tracks and feces at standardized locations) researchers found that, as population density increases, Roosevelt elk will move into other (lower quality) habitats. This was true for two herds of vastly different sizes, although the occupancy rate remained comparable.

Finally, Hiney et. al looks at recruiting experienced anglers and using citizen science to help document and survey the native Coastal Rainbow Trout population of Grass Valley Creek Reservoir. The authors look at methods of overcoming the time and resource limitations of assessing wild trout populations.

Also included in this issue are reviews of two books that make meaningful contributions to the field of wildlife research.

As it has for the past 104 years, California Fish and Game continues to publish high-quality, peer-reviewed science that contributes to the understanding and conservation of California’s wildlife. We look forward to witnessing the contributions of the next installment.

Categories: California Fish and Game Journal
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