Featured Scientist

Tim working a deer capture in Round Valley. The deer was captured with a net gun, blindfolded, and hobbled for helicopter transport to base camp or a central processing station.


Tim radio-collared and took samples from this anesthetized black bear during the 2016 Eastern Sierra Black Bear Study.

Tim Taylor is an environmental scientist for CDFW’s Inland Desert Region, which includes Imperial, Inyo, Mono, Riverside and San Bernardino counties. He has spent his entire 17-year CDFW career in a single area of study – the Eastern Sierra – and he is only the third Mono County unit biologist in department history.

Like many other CDFW scientists, Tim earned his Bachelor of Science in wildlife management at Humboldt State. The Southern California native did myriad odd jobs to get through college, including working on a ski lift, putting up drywall and even thinning trees and fighting fires. After college, he worked as an independent biologist throughout California, Oregon and Nevada, conducting wildlife assessment surveys for a wide range of threatened and endangered species including desert tortoise, red-legged frog, spotted owl and Sierra Nevada red fox.

Today, Tim’s primary job duties include monitoring diverse wildlife species – including sage grouse, deer, pronghorn and bears – in a part of the state most Californians never have the opportunity to experience.

Who or what inspired you to pursue a career in wildlife biology?

When I was a kid growing up in the June Lake area of the eastern Sierra, I always knew I wanted to be a wildlife biologist. I had the good fortune of getting to know the very first CDFW wildlife biologist for the Mono unit, Andy Anderson, and he took me into the field with him whenever possible. I got to participate in some amazing wildlife work, like trapping and relocating nuisance black bears (when we used to do that!), rearing Canada goose goslings, counting strutting sage-grouse and helping at deer hunter check stations. This work provided me with an early appreciation and knowledge of eastern Sierra wildlife and their habitats, and from that time on, the Mono unit biologist position became my dream job.

After Andy retired, I became good friends with his successor, Ron Thomas. He was also a great mentor. I started working for CDFW in the Sierra Nevada bighorn sheep program with the hope of eventually transferring to the Mono unit position. Fortunately, after Ron retired, I was in the right place at the right time.

What are your current responsibilities?

Working as a unit wildlife biologist requires being a generalist with the knowledge and understanding of all wildlife that inhabit my work area. During any given day I can deal with a number of different wildlife species issues like sage-grouse habitat conservation, mule deer and pronghorn research, nuisance black bear complaints and talking with deer hunters about the best place to find a buck. My duties include wildlife resource assessment, habitat enhancement planning and implementation, hunting management, nuisance wildlife response and environmental review. I am currently involved with a number of different wildlife research projects, including a sage-grouse translocation effort to rescue a small, isolated sub-population near the Mono basin and a GPS collaring study of black bears to determine home range distribution and habitat use.

I also occasionally provide advice on how to reduce human-bear conflicts at the Mountain Warfare Training Center, a US Marine Corps installation in Mono County. I review environmental documents that relate to their training area, and work with new recruits on how to identify animals, as part of their survival training.

Which species do you work with most frequently?

Mule deer are the most conspicuous and widespread large mammal in the eastern Sierra. Mono county supports five large migratory herds. I manage 2 mule deer hunt zones, X12 and X9a. Hunt zone X12 comprises three herds that occupy northern Mono County. These are interstate herds that are jointly managed for hunting purposes by CDFW and the Nevada Department of Wildlife. Zone X9a comprises two herds that occupy southern and central Mono County. Those are managed solely by CDFW. Along with other CDFW biologists, I conduct population surveys and collect data on vital rates and nutritional condition as part of an integrated population monitoring approach for assessing the status of local deer herds.

Mono County also supports a large population of greater sage-grouse, which is part of the Bi-state Distinct Population Segment (DPS) of greater sage-grouse. The Bi-state DPS, which is genetically distinct from other sage-grouse across the range, occupies sagebrush habitat in Inyo and Mono counties in California and Douglas, Mineral, Lyon and Esmeralda counties in Nevada. Sage-grouse is a sagebrush obligate species, meaning it relies on sagebrush for its survival. They are also an umbrella species, used in making conservation related decisions that affect the sagebrush ecosystem. Our efforts to conserve the sage-grouse indirectly protects other sagebrush obligate species, such as pygmy rabbit and Brewer’s sparrow, that inhabit the sagebrush ecosystem.

Then there’s the eastern Sierra black bear. Their population has increased dramatically over the last 10 years, and therefore has created numerous management challenges. In most of the rural east side towns there is no regular garbage pickup, so people store their trash and take it to a landfill. This creates a situation where bears have open access to garbage that is not properly secured in a building or bear-proof container. Once a bear has become food-conditioned, it’s pretty much over. It will start breaking into homes and cabins next.

What project or accomplishment are you most proud of?

In 2007, CDFW acquired 1,160 acres of critical greater sage-grouse habitat in northern Mono County, which included two strutting grounds, brood rearing meadows and winter habitat. Approximately 900 of the 1,160 acres was proposed to be subdivided into 40 acre parcels, which included the only two remaining leks for this sub-population of sage-grouse, as well as some critical mule deer migration and summer range habitat. CDFW acted in a timely manner in acquiring the property, and in doing so, prevented the loss of this critical sage-grouse habitat.

Without the acquisition and eventual conversion of the property into a State Wildlife Area, these leks would have been destroyed resulting in the extirpation of this sage-grouse sub-population.

The acquisition was funded by the Wildlife Conservation Board, and was especially important because it was one of the many conservation actions that helped to prevent the federal listing of the Bi-state greater sage-grouse.

What project would you most like to do, given unlimited time or resources?

I would implement several much needed wildlife crossing projects that would include a combination of underpasses, overpasses and fencing to allow deer, bears and other wildlife safe passage across highway 395 in Mono County.

What do you love most about your job?

The fact that I have the flexibility to work with so many different wildlife species on so many different projects.

What advice would you have for a young scientist wanting to do what you do?

Try to become as diversified as possible with respect to your knowledge of wildlife throughout the state. Working as a unit biologist requires multiple species management so become a naturalist and develop a broad understanding of the species that inhabit your work area.

Photos courtesy of Tim Taylor
Top photo: Tim working on a Round Valley deer herd capture team

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.