Featured Scientist

  • January 28, 2022
Kevin Kwak, with equipment in hand and on his back, prepares to electrofish a stream.

Kevin Kwak prepares to electrofish a stream.

Kevin Kwak shows off an impressive spiny lobster he caught diving.
Kevin Kwak with an impressive spiny lobster he caught while diving.

Kevin Kwak is a fisheries veterinarian for the California Department of Fish and Wildlife (CDFW) – one of only two fisheries veterinarians in the entire department. Kevin holds a doctorate degree in fish virology and a doctorate in veterinary medicine from UC Davis, where he also earned his undergraduate degree in evolution and ecology. Kevin joined CDFW in 2012 after working as a practicing veterinarian for a small animal and exotic animal clinic for a few years following his studies at UC Davis.

Based out of CDFW’s Fish Health Lab in Rancho Cordova, Kevin’s work takes him throughout the state. His primary responsibility is diagnosing disease outbreaks and coordinating treatment plans at CDFW’s fish hatcheries. He also investigates wild fish population die-offs and conducts health assessments any time hatchery or wild fish are moved, relocated or rescued to ensure disease is not being introduced into new environments or spread to other fish populations.

Most recently, Kevin developed an innovative treatment for hatchery Chinook salmon suffering from a Thiamine – or Vitamin B1 – deficiency, which is believed to be linked to salmon foraging to a large degree on anchovies in the ocean compared to a more diverse diet. A lack of Thiamine in returning female salmon causes developmental problems and even death in fry salmon. Kevin developed a method to treat the Thiamine deficiency at egg fertilization to avoid any developmental issues.

Born and raised in the Los Angeles area, Kevin’s interest in science and the natural world was ignited as a child by the classic television series “Mutual of Omaha’s Wild Kingdom,” which he watched Sunday nights with his family.

An avid hunter and angler, Kevin particularly enjoys free diving and SCUBA diving – especially for spiny lobster. He also keeps busy away from work introducing his two young children to these pursuits and the outdoors.

CDFW Photos

Categories: Featured Scientist
  • August 7, 2019

Two white males kneeling with bows and arrows next to deceased turkey on wooden cart. Young white boy kneeling on cart, behind turkey.
In the Fish family, hunting and fishing is a family affair. Max Fish, right, accompanied by his son and brother, pose for a photo after a successful archery hunt for wild turkey.

White male wearing grey, black, and yellow jacket and black pants holding up large halibut standing next to white female wearing black pants and blue jacket with hood up holding large halibut. Both are standing on a boat on the water. Partly cloudy sky in background.
Fishing in Alaska, Max and his wife, Carly, show off their catch.

White male wearing blue t-shirt, ball cap, and sunglasses holding fishing rod in one hand and small fish in another standing on beach next to young girl and young boy. Overcast sky and water in background.
As a father of two young children, Max makes it a priority to take his kids fishing, hunting and into the outdoors every chance he gets. Max and his son, Ryland, and daughter, Ellie, spend time surf fishing in Southern California.

There is not a more appropriately named employee anywhere within CDFW than Max Fish. An environmental scientist with the Inland Fisheries Assessment and Monitoring Program, Max is tasked with, well, helping to maximize fish and fishing opportunities within California’s inland lakes and reservoirs. He is based in West Sacramento.

The tools of his trade include the heavy duty, Smith-Root SR18 electrofishing boat he captains, a research vessel that can pump 170 to 1,000 volts of electricity through the water, temporarily stunning fish to the surface in order to survey populations and assess health in the state’s inland waters.

From Kokanee Salmon to crappie and catfish, Max works with more than three dozen inland fish species found in California. He also collects and analyzes all the data submitted by tournament anglers and fishing contests throughout the state.

Born and raised in Palo Alto, Max earned a bachelor’s degree in wildlife and fish conservation biology from UC Davis and joined CDFW shortly after graduating in 2007.

You’ve seen the data from all the big bass tournaments. Where would you send someone interested in catching a really big black bass?

We have several species of black bass in California, which are largemouth, smallmouth, spotted, Alabama and redeye.

My area of expertise is really in northern California. I’d start with any of our central California lakes that have Kokanee Salmon populations. California holds the world record for Alabama Bass out of New Bullards Bar Reservoir (Yuba County). For awhile, it seemed like New Bullards Bar would kick out a new world record bass every season. Right now, the world record fish is sitting at just about 11 ½ pounds.

For Largemouth Bass, we don’t have the world record but we’re close. Of the top 25 largest Largemouth Bass ever caught anywhere in the world, 20 have come from California – all from Southern California lakes. In northern California, it’s hard to beat the quality of large fish in Clear Lake (Lake County) and the California Delta.

Tell us about the special projects you’re involved with.

I work on a program to promote and expand Sacramento Perch. Sacramento Perch are the only species of sunfish native to California. They are the only native sunfish west of the Rockies. They are now extirpated from their native range in California, which was the Delta, but we’ve got them in about 20 lakes where they’ve been translocated.

We’ve been trying to promote the Sacramento Perch on a variety of fronts – for private industry, for private stocking and recreational angling. There are a lot of private landowners who are really interested in native fish, especially native gamefish that are warm-water tolerant. There’s really only one – and that’s the Sacramento Perch. So we’ve been working on that front. We’ve collected all the tissue samples to identify which populations are more genetically robust, more diverse and suitable to create new populations.

Can Sacramento Perch be reintroduced into the Delta or are there too many other predatory fish there now?

The literature shows that predators aren’t as big of a problem as are competitors. Sacramento Perch evolved in California when the main competitors on the valley floor were Pikeminnow and Steelhead. All the introduced sunfish from the Midwest had dozens of competitors they had to compete with so they developed breeding strategies and feeding strategies that are really aggressive.

Sacramento Perch just don’t have that. So when you put them in an environment with a bunch of Green Sunfish or Bluegill or Redear Sunfish, they just seem to get pushed out over the course of a few years. So that’s been, I think, by far the biggest challenge in trying to expand them. All of our surface waters in the Sacramento Valley and the foothills have sunfish in them.

But when you talk to people about Sacramento Perch, they get super excited to hear about a native gamefish that’s warm-water tolerant. You can stock them in a pond and they will do great. They will survive under ice. As far as environmental conditions go, they are super tolerant.

What’s happening with California’s landlocked salmon such as Kokanee and Chinook?

One of the things I’m doing now is a mark and recapture study of Kokanee Salmon. Last year, we began marking fish by clipping the adipose fins of all the Kokanee we stocked into Stampede Reservoir (Sierra County). Stampede Reservoir is our brood stock water for Kokanee Salmon. In lakes like Stampede where there is natural recruitment and a stocking allotment it’s tough to make management decisions when you don’t know what relative contributions either of those make to the fishery. By fin-clipping those fish when we stock them, we can see how many return to spawn or how many show up in anglers’ catches. We can see the relative number of hatchery fish versus natural fish and determine if we are stocking too many, too few and adjust our stocking accordingly. In 2019, we released marked Kokanee into New Melones Reservoir (Calaveras/Tuolumne counties).

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

I’d do two. One is create a Sacramento Perch broodstock facility. Like I said, we have an idea from our genetic work on where to get our broodstock, but there is the question of where to put them. We’d like something on state lands that we can control. A natural pond could function as a production facility as well as a grow-out facility but finding something that doesn’t already have non-native fish and has a secure water source that is not going to go dry is a challenge. A solar-powered well would be perfect. We could dig a pond, put in a well, know that we would have good water – but all of that costs money. We are headed there but it is slow going.

I’d also expand our Kokanee mark and recapture study. Instead of fin-clipping 40,000 Kokanee a year, I would love to do all of the Kokanee we plant – but that’s the expensive part. Collecting the data on the back end isn’t too bad. We use creel surveys of angler-caught fish. At least in Stampede, that’s where we collect our eggs so we are seeing all the fish that come up the river to spawn anyway. Maybe we wouldn’t have to fin-clip all of the fish but at least the ones we stock into lakes with naturally reproducing populations. We could get a lot more data a lot more efficiently.

What advice would you give a young person today thinking about a career in natural resources?

If you haven’t already, read “A Sand County Almanac” by Aldo Leopold. That book had an impact on me and still does to this day. I think it’s a valuable read for anyone going into this field.

What about the book spoke to you?

It’s just the way Aldo Leopold viewed the natural world and the way we as human beings fit into it.

Away from work, where are we most likely to find you?

Usually fishing, hunting, backpacking or otherwise spending time with family. It depends on the season. In the spring, I really enjoy turkey hunting and fishing – stripers in the river, and Kokanee, bass and crappie in lakes. In the fall, I’m deer hunting, duck hunting, crabbing, and fishing for rockfish.

I hunt and fish for food – not out of necessity but because I feel more integrated into the natural world and more connected to the earth. I think it’s a uniquely satisfying experience in our society that’s increasingly disconnected from the earth. It’s what Aldo Leopold wrote a long time ago that holds true today: “There is value in any experience that reminds us of our dependency on the soil, plant, animal, man food chain.”

CDFW Photos. Top Photo: Max Fish captains a CDFW electrofishing boat in the Sacramento-San Joaquin Delta in January to help collect Largemouth Bass for live display at the International Sportsmen’s Exposition in Sacramento in January.

Categories: Featured Scientist
  • December 24, 2018

man standing in river pool surrounded by large boulders and hillside
Scott Harris participates on fish survey on the Middle Fork Eel River. CDFW Photo by Amanda Ekstrand.

Scott L. Harris is an environmental scientist with CDFW’s Northern Region, based in Mendocino County. Scott is responsible for monitoring and managing salmonid populations in the Eel River and Mendocino coast watersheds as part of the North Central District Salmon and Steelhead Management Project, a multi-faceted effort funded through the Sport Fish Restoration Act (SFRA). His fieldwork includes counting adult salmon and steelhead through spawning ground surveys and ladder counts at the Van Arsdale Fisheries Station (VAFS), counting juvenile salmonids migrating to the ocean and determining resident trout distribution in the Mendocino National Forest. Much of his time is spent at the VAFS fish ladder studying the biological effects of water releases from the Potter Valley Project (PVP). He also consults on fish passage issues, evaluating man-made structures (fish ladders, etc.) at road crossings to determine whether they are damaged, blocked or in need of cleaning, and whether the design is adequate to meet the need.

What or who inspired you to become a scientist?

The “what” is water. I am fascinated with water, salt or fresh. I grew up in Southern California and spent most of my time at the beach. When I was about 10, I was instantly hooked on the ocean when I first put a mask on and saw what was taking place under the waves. At about the same age, I found a local stream and was mesmerized by the number of animals that lived in and around that stream. Then came my love affair with PBS, NOVA, Wild Kingdom, the local library, etc. I’m guessing a lot of folks went through a similar progression.

The “who” probably started with Carl Sagan, Marlin Perkins (and, of course, Jim Fowler, Perkins’ assistant), my friend’s mom (a science teacher) and my dad (an engineer). Today I am surrounded by many colleagues who feed my interest in science and I would bet these folks are inspirational for many others, young and old.

My fascination with water continues today with my job. However, my work with the department requires the understanding of the physical aspects of water, not just the biological aspects. In stream restoration, it is necessary that one understands hydrology and fluvial (movement of sediment in water) processes.

What is a typical day like for you at work?

If there was a typical day, I would probably quit! There are days when I am greeted at my door by hunters that need a bear or deer validated. When a hunter takes a deer or bear, the animal must be reviewed and then some paperwork is completed indicating that the take was legal. In addition, a tooth must be extracted from bears. The tooth is used to determine age and this information is used as a tool in management of our black bear populations. Sometimes I’m asked to pull a bear tooth in the Safeway parking lot or at the gas station. This is not exactly fisheries but I absolutely believe I am part of a team. Typically, if I receive a call before 9 a.m., I know my day will change and that someone needs help. Many days include a wild card. I wouldn’t have it any other way!

I am one of the lucky ones. During the year, I spend 90 percent of my time in the field. So, 90 percent of the year, I leave my office excited and with a smile on my face, ready to learn something new or hopefully teach someone something new.

What is your favorite species to interact with or study?

For those who know me, they know how important herps and birds are to me. I bring that knowledge to many of my colleagues. However, there are two species that I have a special fondness for: The Middle Fork Eel River summer Steelhead and the Pacific Lamprey.

We conduct an annual free dive/snorkel survey on the Middle Fork Eel River that was named the “Death March” 30 or more years ago. This 26-mile, five-day survey is conducted in the Middle Eel/Yolla Bolly Wilderness located in Trinity and Mendocino counties with the intent to enumerate adult summer Steelhead. Dozens of department employees have been on the Death March over the years and I guarantee that they have yet to forget it. This annual survey began in 1966.

In 2009, I took over the activities at the Van Arsdale Fisheries Station located in the upper Eel River. Through our activities there, Pacific Lamprey became a target species for study. I have been collaborating with two people, Damon Goodman with the U.S. Fish and Wildlife Service and Stewart Reid with Western Fishes, both of whom are known for their background and expertise on Pacific Lamprey. We have all learned some amazing things about Pacific Lamprey. There has already been one “white” paper written from this work and I believe there are at least another two in the making.

What aspect of working on monitoring salmonid populations is the most challenging?

The projects that are most challenging are typically those with numerous stakeholders or interested parties. I have been involved with the Willits Bypass for decades and this project has seen multiple agencies and interested parties over time. Keep in mind, the Willits Bypass was started in 1955, so the number of interested parties could be considered myriad. Another project with a high number of interested parties is the PVP. With the Federal Energy Regulatory Commission relicensing effort underway for the PVP, things are getting interesting.

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

There are a few projects that come to mind, but the one that I will tell you about is more about how I have volunteered my time as a mentor. About 10 years ago, a neighbor introduced me to her son, Bryan. Bryan needed a science fair project. Before we decided on a project, I thought it would be good to involve Bryan in some of the fieldwork we conduct. So, he ended up getting a taste of salmon spawning ground surveys, juvenile outmigrant trapping, backpack electrofishing – he even participated in the infamous Death March.

The project we decided on was, to say the least, controversial. The title of the project was “Why is there no water in Alder Creek.” And yes, this project had everything to do with the effect of pot growing on aquatic resources. We conducted the fieldwork on weekends due to Bryan’s school schedule and we worked on maps and tables in the evenings. This project led to numerous field visits with department enforcement and Bureau of Land Management enforcement. Things got a little hairy in the field. It also led to a few threats over the phone. The bottom line is, Bryan’s project won first place at the state level and he even got to have lunch with retired Governor Deukmejian. I remain in touch with Bryan to this day, I suppose, as a father figure.

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

For myself, and probably for most of us in the department who conduct monitoring, research and habitat restoration, it is resources. Not having resources (money) to implement more of what we are already doing is maddening. The challenge is to be OK with so little help.

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

In, at least, our state’s three largest rivers (Sacramento, Klamath and Eel) I would like to see aquatic habitat (rivers, estuaries, lagoons, vernal pools, etc.) restoration of every conceivable type take place, and as quickly as possible. With the implementation of the restoration would come monitoring the effectiveness of the implementation by evaluating the response by plants, animals and the physical environment.

Any advice for people considering careers in science or natural resources?

Certainly, education plays a key role when it comes to our natural resources and science. Education also includes get involved in internships and/or volunteering. I have mentored 15 AmeriCorps members, two of whom went on to get doctorate degrees in fisheries ecology.

Top photo: Scott Harris hoists a bucket during a fish rescue on Feliz Creek. CDFW photo by Derek Acomb

Categories: Featured Scientist
  • January 25, 2018

A man with a dark goatee, wearing black with an orange safety vest, kneels among dead reeds and low vegetation, holding a field notebook

Morgan Knechtle is an environmental scientist with CDFW’s Northern Region in Yreka. He works on the Klamath River Project, which has a primary focus of estimating the return of adult salmon and steelhead to the Klamath and Trinity rivers. He is responsible for multiple field projects that manage salmonids in the Klamath River Basin, such as operating adult salmonid counting stations and coordinating adult spawning ground surveys on the Shasta River, Scott River and Bogus Creek, three highly productive salmonid tributaries to the Klamath River in Siskiyou County. Knechtle also assists with adult recovery efforts, which involve collecting biological information from returning adult salmon at Iron Gate Hatchery, and serves as one of CDFW’s technical representatives for the Klamath Dam Decommissioning Project, which involves the proposed elimination of four hydroelectric dams in northern California and Southern Oregon.

Knechtle earned a Bachelor of Science degree in freshwater fisheries from Humboldt State University and got his first job with CDFW as a scientific aide in the Russian River watershed. He was hired permanently in 2000 and spent four years working on salmonid life cycle monitoring stations on the Mendocino coast. Since 2004, he has worked with salmonids in the Klamath Basin, both on the Trinity River and in the tributaries to the Klamath River in Siskiyou County.

Who or what inspired you to become a scientist?

My love for rivers inspired me to become a scientist. During college at Humboldt State University, I was spending all of my free time fishing for salmon and steelhead and came to the realization that I could study these animals and make a living working with them.

The ability to be an advocate for fishery resources brought me to CDFW. CDFW is one of the only places a scientist can work with fisheries and truly be an objective voice for the resource. Many other organizations do not have this luxury.

What is a typical day like for you at work?

It depends on the time of year. During the fall and winter when adult salmonids are returning to the Klamath River, my world is extremely busy running and participating in multiple field projects monitoring the return of these amazing species. During the spring and summer, I spend much more time in the office crunching numbers and writing reports.

My Chinook salmon work focuses on providing information that can help accurately forecast abundance. This enables us to provide fishing opportunities while maintaining enough fish in the river for future generations. My coho salmon monitoring work focuses on providing accurate abundance information to track the status and trends of this endangered species over time.

As a technical expert on the Klamath Dam Decommissioning Project, in cooperation with other technical experts from other state and federal agencies, I help minimize effects to aquatic species inhabiting the Klamath River during the decommissioning phase of the project. Additionally, I participate in post-dam removal planning projects, including creating plans on how to implement the Iron Gate Hatchery post dam removal and coordinate with Oregon scientists on the reintroduction of salmon above Iron Gate Dam, with a goal of ensuring the recovery of salmonids and aquatic species above the project area.

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

Although the project is not yet complete, the Klamath Dam Decommissioning Project has the potential to be the most rewarding project I have worked on. It stands to be the largest river restoration project to ever be completed in North America, and given that status, as one can imagine, the project has a lot of moving parts. The potential benefits to salmonids in the Klamath and the improvements to the health of the river itself could be enormous. The long-term predicted improvements to water quality, habitat availability, natural flow dynamics and restoration of natural processes to the Klamath River will improve conditions, for not only anadromous salmon and steelhead but also the rest of the plant and animal community that depend on the river for part or all of their life history.

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

It is extremely challenging when social and political concerns get mixed in with natural resource management. Working with coho salmon in the Klamath Basin has been very challenging due to its listed status and the fact that their abundance is extremely low.

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

With unlimited funding, I would like to track and monitor the recovery of spring Chinook in the upper Klamath River post dam removal. They are nearly extinct and they are thought to once have been the most abundant species in the Klamath River Basin.

What aspect of working on the Klamath River is particularly challenging or rewarding?

Multiple stakeholders -- which include Native American tribes, federal and state trustee agencies, and freshwater and ocean anglers -- in the Klamath Basin make some aspects of salmon management challenging. However, when progress is made to restore the river, it is also extremely rewarding because you know that groups with very different perspectives have come together, negotiated agreement and reached consensus on difficult issues.

What is your favorite species to interact with or study?

Steelhead trout are my favorite species to work with. Steelhead are the most elusive of the Klamath salmonids and their complex life history make them a very difficult species to study. They are also my favorite fish to catch.

Any advice for people considering careers in science or natural resources?

The most obvious is for folks to stay in school and graduate from college. In addition, volunteering and interning in their field of interest early in their education is a benefit to get a taste of what the career might really be like.

CDFW photos of Morgan Knechtle working along the Shasta River.

Categories: Featured Scientist
  • March 30, 2017

Sara Borok is an environmental scientist with the Klamath River project. She is responsible for counting the sport harvest on the Klamath and Trinity Rivers and for gathering natural spawner escapement data (which involves counting deceased fish which have finished spawning) on the Salmon River and approximately three dozen tributaries of the Klamath River above the Trinity River. She is also the co-coordinator of the Klamath Fish Health Assessment Team.

Borok initially studied forestry at Humboldt State University before changing her major and earning a Bachelor of Science degree in wildlife management. She jokes that she also “majored in minors” by earning minors in forestry, fisheries, art and music.

She has worked her entire CDFW career in the Klamath Basin, striving to “bridge the desires of our constituents and protecting the health of the fishery” as she counted live fish going out of the river and the dead fish that returned and spawned.

Who or what inspired you to become a scientist?

Even when I was young I knew I wanted to work in the outdoors. I am from the era of “Mutual of Omaha’s Wild Kingdom” and I always wanted to be the assistant, “Jim.” He always had the cool jobs! I grew up in Southern California, and when I started high school, there was a wonderful summer school class, Outdoor Biology, that taught basic sampling techniques. We went to Catalina Island to do some marsh sampling, and I got hooked. I used to seek out wild places, often riding my bike up to Will Rogers State Park in Pacific Palisades and then hiking in four miles to find some solitude.

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

When I was 16, I worked for the Youth Conservation Corps, and later at Will Rogers State Park, Craters of the Moon National Monument and Preserve, Oregon Caves National Monument and Preserve and at Ft. Clatsop, which is part of Lewis and Clark National Historic Park. I started out with CDFW in 1985 as a seasonal aid working the Klamath Creel Crew for Jim Hopelain, a wildlife biologist who at that time served in my current position. I fell in love with the idea of getting paid to do this job out in the woods. I still cannot believe that I get paid for what I get to do.

What is a typical day like for you at work?

During the “creel season” in April through November, I help the crew at busy spots on the Klamath River by interviewing anglers about their effort and catch of salmon and steelhead. We keep track of the numbers because they dictate size restrictions. Once a certain number of fish have been caught, anglers can’t keep the big ones anymore.

I also help out during the “carcass season” in October through December by organizing crews with individuals drawn from CDFW as well as other state agencies, tribes, volunteer groups and schools. Those crews then are kept quite busy counting dead fish to determine the “floor escapement,” or the number of fish that are returning to the river to spawn in natural areas. We need to meet a minimum number before we can allow any kind of harvest.

I field a lot of complaints from anglers, typically regarding our regulations! It is helpful that I have a great group of people working for me and with me who do a lot of the hard work.

What is most challenging about working with fish?

I would say that wading through large amounts of swift-moving water is the most challenging aspect. In years such as this past season, when we had such heavy rains, we had a hard time getting out on the tributaries to get good counts of the few spawned-out fish that were out there. Other challenges, ones that have nothing to do with the weather, are gaining access to specific areas from private landowners and the simple matter of having to cover such a large geographic area.

What is special about working in the Klamath Basin?

The Klamath kind of grows on you. I have been working in the basin for 32 years (wow, it doesn’t seem that long!). Working with live fish is the best, but even during spawning season the beauty out on the rivers makes up for dealing with dead fish. There are also really wonderful people living and working up here. I have worked every Labor Day Weekend for the last 20 years, and I get to see some of the same families that come up to fish then. It is like a big family reunion.

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

I work with a huge cooperative group of agencies, tribes, non-government groups, volunteers and school kids. We all get along and work hard to get the work done. What is really rewarding to me is that we have school kids who come out and do the spawner surveys with us. The students are actually walking through the water along with CDFW staff, counting carcasses. Their enthusiasm in being out in the fields is always refreshing and amusing. There have been a few who fell in love with this type of work and went on to school in this type of field and then came back to work on this very project.

Any advice for people considering careers in science or natural resources?

Learn basic accounting, people management, vehicle repairs, public relations and logistics, as you will be spending more time on this kind of stuff than on the science.

I have been thinking of teaching a short class at Humboldt State University on all the other stuff like this that you will need to be a biologist/environmental scientist. People should also learn to work without the aid of fancy gadgets, as there may not be cell reception when you are out in the river or woods, and gadgets tend to fail when you need those most. Learn to improvise!

Categories: Featured Scientist
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