Featured Scientist

Laura Cockrell with an endangered Green sturgeon she tagged in the Sacramento River for a sturgeon movement study


Laura holds a Western pond turtle at Upper Butte Basin Wildlife Area.


Laura swabs a hunter-harvested Northern pintail for Avian Influenza sampling in 2007 at the Gray Lodge Wildlife Area.

Laura Cockrell is an environmental scientist at the Upper Butte Basin Wildlife Area, which is made up of three units covering nearly 9,700 acres in Butte and Glenn counties. Her duties include coordinating and conducting biological surveys on the wildlife area, managing wood duck nesting boxes, coordinating with volunteers and interacting with partners, including governmental agencies and non-government organizations. While most of her work involves surveying for game species, she has also captured giant garter snakes and western pond turtles for studies, and conducted surveys for yellow-billed cuckoos and Swainson’s hawks. Laura can also regularly be found planning habitat improvement and maintenance projects, writing reports, creating maps designed for public use on the wildlife area and generally assisting the public.

Laura graduated from California State University, Chico in 2007 with a Bachelor of Science in Biological Science with an emphasis in Wildlife Biology. She earned a Master of Science in Biology with a concentration on Applied Ecology from Eastern Kentucky University. Her thesis used Landsat imagery to evaluate trumpeter swan nesting sites in Yellowstone National Park.

Prior to working at the Upper Butte Basin Wildlife Area, she worked for the International Halibut Commission in Dutch Harbor, and for California Waterfowl in the Sacramento Valley, where she worked on summer mallard banding, pintail rocket netting, nest searches and wetland monitoring.

What led you into a career as a wildlife biologist?

I always enjoyed being outside and exploring as a kid. It took me a little while to find my path in college, but I chose to major in biology because studying ecology and nature sounded like a good chance to be outside every day. I signed up for a waterfowl course, and my passion for wildlife really took off after that.

Who or what brought you to CDFW? What inspires you to stay?

When I first started as a scientific aid with the department almost 11 years ago, I was working on the Avian Influenza Project. I swabbed hunter-harvested birds at the check station to be tested for avian influenza in the lab, and surveyed for bird die-offs throughout the region. I had never worked alone before, and it taught me a lot about how important it is to stay focused and on task when you are by yourself!

What inspires me to stay with the department is the potential I see for us to fulfill the goals of our management plan, and to improve habitat on the lands we have been entrusted to manage.

What is a typical day like for you at work?

It depends on the season. Waterfowl season is our busiest season as far as public use. It runs from late October through the beginning of February, but the preparation begins much earlier. During waterfowl season, I am usually in the office or at the check station. After waterfowl season ends, I finalize our hunt records for the end of season report and everyone is out monitoring the area flooding or inspecting damage from flooding. In the spring when we are in full survey mode, I will probably be out in the field before sunrise counting pheasant or quail. During the summer, I am usually in the field banding or in the office working on grant reports. Fall brings us back into preparation for the hunting seasons, where we have to prepare for September dove hunts, the J-9 zone deer hunt and waterfowl season.

What is your favorite species to interact with or study?

I have really enjoyed getting to work with western pond turtles and giant garter snakes. I took herpetology in college and it was great but “herps” were not really my thing until I got to work with them more. Any time we get to work with protected species and species of special concern is rewarding, and it is not something we get to do very often. Seeing protected species thrive on our wildlife areas means the hard work that goes into developing protections is helping local populations persist, and if the local population becomes healthy enough to expand maybe they can rebound throughout their range.

What is the most rewarding project that you have worked on for CDFW?

Upper Butte Basin Wildlife Area is one of the few wildlife areas with an agriculture lease, so we work with our farmers to support wildlife-friendly agriculture practices. Because of the winter flooding this year, some of the rice fields were too wet during planting season, and farmers will be enrolling those fields in the BirdReturns program, which is offered by The Nature Conservancy in partnership with the California Rice Commission. The Nature Conservancy and the California Rice Commission began this program in 2014 to compensate farmers who provide pop-up habitat for migratory shorebirds in the fall and spring by flooding fallow rice fields. We are planning shorebird surveys during fall migration and I am so excited to see how shorebirds will react, hopefully by returning to the area. During the shorebird survey, we will drive down the roads through the flooded rice fields and count the number and types of shorebirds that are using the fields. Normally, if the fields have been planted in rice, they would not be usable by the birds because they are looking for mudflats, not rice fields. We would hope to see a high diversity of species and large amounts of birds using the flooded rice fields.

What is it about the work you do that you would most like us to know?

There are many constraints on the work we do that are created by factors outside our control. A large part of the work on our wildlife area is managing wetlands, but the drought brought a lot of challenges with water management. We work with what we have, but sometimes it is not a lot and that can be frustrating.

If you had free reign and unlimited funding, what scientific project would you most like to do?

Wildlife overpasses/underpasses! Our wildlife area has a highway that bisects one of the units, and the amount of wildlife killed by vehicles is such a shame. A few years ago, we had four deer killed in a quarter-mile stretch in less than a week, and this winter someone ended up driving into a waterway at one of our units to avoid a collision with a deer! There are the standard “deer crossing” signs, but people often drive well over the speed limit and put themselves and wildlife at risk for a collision. There has been a great deal of success in reducing wildlife collisions where wildlife overpasses and underpasses were created. I would love build underpasses with elevated roadways for all the major roadways around our units.

What is the most challenging aspect of your career as an environmental scientist?

More than once, I have had to remind myself, “You signed up for this, so put a smile on your face and get it done!” Walking in waders to check traps when it is 110 degrees out is not fun. Examining a carcass that has been rotting for a week is not fun. Cleaning up garbage is not fun. However, all of those things are critical for what we do! So put a smile on your face, get it done and get on with it.

Is there a preconception about scientists you would like to dispel?

One of my classmates in college told me that I should switch to microbiology because “there is no future in studying plants or animals.” We need to understand our environment, how we interact with it and the impacts we make. Scientists are not always in a lab – they are out in the field, too. Obviously, I did not agree with his assessment or I would be a microbiologist! The guy that I was talking to felt like, career-wise, the money was in lab work and microbiology rather than fieldwork. Part of me can understand that line of reasoning, as there are more jobs with the medical profession if you target microbiology, but if that is not where your passion is then why would you take that path?

All photos courtesy of Laura Cockrell.

Environmental Scientist Tom Greiner at the helm of CDFW research vessel Triakis.


CDFW Research Vessel Triakis on San Francisco Bay


Greiner holds a young leopard shark


Greiner on Humboldt Bay


Tom Greiner… just for the halibut

Thomas Greiner is an environmental scientist for the Aquaculture and Bays Management Project in CDFW’s Marine Region. He has more than 23 years experience with the department. Based out of the Santa Rosa office, his main duties include monitoring and management of the commercial herring fishery in San Francisco Bay and biological assessment of California’s estuaries.

Tom earned a double major in general Biology and Fine Arts from Eastern Michigan University. He came to CDFW in 1989 as a scientific aid. Afterwards he pursued a Master’s degree at Humboldt State University. After another stint as a scientific aide, Tom was hired as a Senior Laboratory Assistant for the CDFW’s San Francisco Bay Study and later promoted to Marine Biologist and Associate Biologist and is now an Environmental Scientist.

Who or what inspired you to become a scientist?

I have had an interest in nature, and animals in particular, since I was knee-high to a porcupine. My mother’s willingness to put up with all sorts of critters in the house certainly paved the way. Along the way several people tried to warn me that there are very few jobs in natural resources, but my stubbornness won out.

Can you give us an overview of the herring fishery and tell us why it’s important?

The primary commercial herring fishery in California occurs in San Francisco Bay. It is primarily a roe fishery with its product exported to Japan, where it is considered a delicacy and is a traditional holiday gift. There is also a smaller herring-eggs-on-kelp fishery and a fresh fish fishery for local consumption. In addition, there is a sport fishery for bait and food.

The San Francisco Bay herring fishery was once highly profitable, but a reduction in the price per ton paid to commercial fishers, due to competition from other fishing areas and diminishing demand in Japan, has led to reduced fishing effort.

What is a typical day like for you at work?

A typical day is spent in the office manipulating data and writing or editing documents, but work still takes me out into the field. In the summer, I occasionally help with fish rescues or sample the local estuaries by kayak using beach seines. Winter is my busy field season. I sample Pacific herring in San Francisco Bay aboard a research vessel by deploying a mid-water trawl. On a trawl day I typically get up long before sunrise and meet the crew, which consists of one boat operator (me or one of the other Herring Team biologists) and two winch operators. Once on the water, we look for cormorants, gulls, seals and sea lions to help us find schools of fish. After we have found a school, the vessel operator plans a strategy for the trawl which includes assessing potential hazards, determining tow direction (we tow with the current), and amount of line we need to let out to get the net down to the school of fish. We avoid trawling in rough seas or swift currents, but things can still get dicey – between vessel breakdowns, tangling up or ripping the net, and getting the net stuck in the substrate, trawling is often an adventure.

We collect data on age, length, weight and reproductive status from these samples. We use this data to assess condition of the San Francisco Bay Pacific herring spawning population. This information, along with a spawning biomass estimate made by another Herring Team member, is used to set the next season’s commercial fishing quota.

Managing the quota requires up to the hour information on herring fishing activity and landings along with coordinated, decisive action when calling for closure of the fishery to prevent over-exploitation of the herring resource. I coordinate fishery closures with the Herring Team, CDFW enforcement and the U.S. Coast Guard.

What is it about the work you do that you find most interesting or rewarding?

It is very rewarding working as part of a well-oiled (okay, occasionally squeaky) team to protect our natural resources. Precision teamwork is required both in the management of the commercial fishery and safely operating our sampling vessel.

What is the accomplishment you’re most proud of?

There isn’t one single accomplishment that I pride myself on above others, but instead it is my dependable, consistent, quality work. Through many years of study, I have developed a good reputation for reliable identification of estuarine fish and macroinvertebrate species. Continuous identification practice is important as I recently had a SNAFU concerning juvenile jacksmelt and topsmelt IDs – juvenile fish identification can be very tricky and the characteristics used to differentiate species in adult fish don’t always apply to the little guys.

If you had free reign and unlimited funding, what scientific project would you most like to do?

Restoring and protecting habitat and native wildlife and monitoring the recovery would be very rewarding. Healthy and varied habitat is often the key component in an ecosystem. One nice part is that this can be done on a small scale and some benefits may still be observed. Planting one tree can make a difference, especially in an urban area that lacks trees.

Are you a recreational angler (or hunter) yourself?

It has been quite a while, but I occasionally fish for food. I think that my main purpose in fishing is to make my friends feel good because they catch more fish than I do. It’s been much longer since I’ve hunted, but I also support the idea of hunting for food.

Do you have any advice for people considering careers in science or natural resources?

Get a degree in biological sciences, natural resources or related field. Meeting working biologists is very helpful and volunteering shows motivation. Be flexible in the job locations and positions that you are willing to accept. Very few people get permanent positions with CDFW right out of college. You need to have persistence, persistence, persistence, grit and patience. And learn to be frugal – you won’t make a lot of dough in this profession.

Top Photo: Tom Greiner, Arn Aarreberg and Ryan Watanabe identify and measure fish and invertebrates sampled by beach seine from Estero de San Antonio, a coastal lagoon in northern Marin County.

Anna Burkholder is a senior environmental scientist with the Preparedness Branch of CDFW’s Office of Spill Prevention and Response (OSPR) in Sacramento. She is the statewide Inland Geographic Response Plan Coordinator, working with fellow OSPR staff throughout the state to develop inland response plans for waterways at high risk for an oil spill. She has worked for CDFW for 20 years, most recently joining OSPR in 2016. In addition to her role as response plan coordinator, she is training for two oil spill emergency response positions: wildlife branch director (the position that oversees wildlife response efforts during a spill) and liaison officer (which works to address stakeholders’ concerns during a spill).

Anna earned her Bachelor of Science degree in biology, with an emphasis in zoology, from San Francisco State University. She prefers being outdoors, hiking with her dogs, snowshoeing, paddle boarding and horseback riding. She volunteers with the DOVES Guidance Program, a therapeutic horseback riding program for at-risk kids, as well as for NorCal German Shorthaired Pointer Rescue. She is improving her skills at upland bird hunting, including pheasant and turkey, and is still waiting to take a shot at her first tom.

Who or what inspired you to become a scientist?

When the movie Jaws came out, I was both terrified and fascinated. To this day, it is my favorite movie and I am more thrilled than ever with sharks. I briefly met Peter Benchley, the author of Jaws, several years back at the Monterey Bay Aquarium and that was exciting. He was promoting a new book trying to dispel the terrifying image of Great Whites, which he felt partially responsible for creating. I was also inspired by Dr. John McCosker, a Great White Shark expert that works for the California Academy of Sciences in San Francisco. McCosker had begun investigating why shark attacks occur, assessing their danger to humans in the grand scheme of things. He has worked to help understand the importance of sharks in the ecosystem and how they relate to the health of our oceans.

What got you interested in working with wildlife?

Clearly I would have loved to study sharks but didn’t follow that path. Along the way though, some of my classes at San Francisco State got me interested in some aspects of wildlife. Studying the behavior of snow leopards at the San Francisco Zoo (they sleep a lot!) for my Animal Behavior class, and doing some mark and recapture studies of mice and voles in Pacifica for an Ecology class, were fun experiences.

Who or what brought you to CDFW? What inspires you to stay?

Pure luck brought me to CDFW. After I graduated from college, I was working for a biotech company in Hercules and wasn’t terribly happy with the work. I used to go for walks during my break time and look out over San Pablo Bay and think to myself, “I need a job out there.” While taking an oceanography class at night at a junior college, I was looking at the job board one evening and saw a posting for a temporary scientific aid position with CDFW, working on the Bay Study Project. I got the job and lo and behold, there I was out on a boat every month, sampling fish throughout the Delta and San Francisco Bay (including San Pablo Bay!). I have never looked back.

Twenty years later, I guess it was a good move for me. I stay because I love this department, mostly the people I work with, and the dedication and passion we all have for the environment and the strong desire to protect the species and habitats in the state.

What is a typical day like for you at work?

When I am not traveling to participate in oil spill drills, oil spill workshops or Incident Command System training, I spend time working on the Geographic Response Plan template document that will be used to produce regional plans throughout the state for oil spill response. I coordinate with my OSPR colleagues, as well as other state and federal agencies, oil spill response organizations and industry folks on the development of these documents so they can provide a useful tool in responding to an incident. It’s been great to meet and work with an entirely new set of folks that I haven’t come across in my career until now, and to have a common goal of preparing for oil spills and working to protect the public, the environment and economic resources in our state.

What is the most memorable or rewarding project that you’ve worked on for CDFW?

I’ve spent a lot of time in the field working on boats. I worked on the 2007 Pike Eradication project at Lake Davis, and even got to spend a day escorting Delta and Dawn, the wayward humpback whale cow and calf that swam up the deep water channel to the Port of Sacramento in 2007. We escorted them on the last day they were observed inside the Golden Gate as they made their way through San Pablo Bay and finally back out to the Pacific Ocean.

I would have to say the most rewarding project is shaping up to be my new job with OSPR. The office was established 25 years ago and has a very comprehensive marine program in terms of preparedness and response to oil spills, but since OSPR’s jurisdiction expanded to include inland in 2015, I get to be on the forefront of establishing preparedness plans to protect all waters of the state.

What do you enjoy most about your job?

I work with an amazing group of folks in every part of our department, and we have a common goal of preserving and enhancing the natural environment. Being able to feel proud of the department you work for and cheering on the achievements of others in your field is a great feeling. Not to mention some of the great days in the field, which include flying along the California coast to record data on nesting seabirds, looking for nesting grebes in high mountain lakes and touring the state’s bird and marine mammal rescue and rehabilitation facilities.

Is there a preconception about scientists you would like to dispel?

The term “environmental scientist” encompasses a wide range of job duties within the State of California, including field biologists and environmental planning and permitting staff. We certainly have state scientists who conduct important laboratory research, including folks who work for OSPR and conduct water analysis and DNA fingerprinting on oil products. And what’s wrong with a periodic table? I loved general chemistry class!

Do you have advice for people considering careers in science or natural resources?

If it is what you love to do, then don’t shy away from following that path. You can try different aspects of working in the natural resources field and then focus on what you enjoy the most. I would volunteer or take shorter-term assignments to work with multiple organizations and get experience in different areas. Meet experts in their field and get a foot in the door through internships or part-time jobs. There are so many exciting directions you can go in this field.