Featured Scientist

Forensic Specialist Kelly Carrothers (l) prepares to collect tusk samples at the La Brea Tar Pits, in Los Angeles.
 

Kelly Carrothers is a wildlife forensics specialist with the California Department of Fish and Wildlife. The Wildlife Forensics Laboratory, where Kelly is based, is located in Sacramento. Its purpose is to support the investigation work of CDFW’s Law Enforcement Division.

Kelly was hired about three years ago, after the passage of AB 96, which funded lab equipment and staffing for the purpose of putting a dent in the ivory trading industry. Kelly and her coworkers are assigned with identifying tusk, bone and teeth from a variety of animals, to help bring poachers to justice and ultimately reduce the practice of ivory trading.

Kelly was born and raised in Southern California, then attended the University of California, Davis where she earned degrees in biochemistry and molecular biology. Her master’s degree is in forensic science.

What was the moment you realized what you were going to do for a living?

When I was 16, my father signed me up for a research science course in high school … we had to conduct independent research and take that to the county science fair. So I thought for my project, I wanted to do forensics. I looked at postmortem hair roots of mice to see if we could correlate time of death with just how the hair roots change when they died. I ended up getting third place in the science fair, then continued the project and expanded it the second year. I absolutely loved it and thought this would be a cool field.

What about this kind of work resonates with you?

I love mysteries and I love thrillers. I like to solve the mystery. I like the idea of being able to provide a voice for victims. When an animal is illegally taken, there is often no physical evidence that can point an officer in the direction of the poacher. I love being able to work with the “invisible evidence,” the DNA, to piece together the puzzle of who poached an animal. The DNA from an animal – or lack thereof – can be a really powerful investigatory tool since DNA is almost impossible to get rid of! It is really rewarding to essentially be the “voice” of the animal after it has died, as I might be the only person that can shed light on what happened to the animal by looking at its DNA.

What’s the highlight of working at the Wildlife Forensics Laboratory?

I do primarily wildlife trafficking cases that come through the lab – so, a lot of DNA sequencing for species identification. What is this fur? What’s in this Chinese medicine? I do a lot of the ivory analysis and I’ve been able to develop and validate an ivory genetics DNA-based assay (or procedure for determining what a sample is composed of) for identification of ivory-bearing species under AB 96.

Are there cases that have been prosecuted successfully based on the work you did here?

Back in August 2018, my colleague and I were asked to examine some ivory pieces that had been seized as part of the largest ivory case in state history from the Carlton Gallery in San Diego. Over 300 pieces of ivory were confiscated, worth over $1 million, and we were asked to examine and identify 21 representative pieces. That was also the first case that required the use of the ivory genetics assay I had developed. Through a combination of morphological examination and genetics, we were able to identify the species of origin in all of the 21 pieces, and I was able to establish a Minimum Number of Individuals present in the pieces I genetically tested – meaning I was able to determine that at least four different individual elephants were used to make the ivory pieces. It was really cool to later find out that the defendants were convicted of ivory trafficking and were ordered to pay fines totaling more than $200,000, complete community service and were placed on probation.

How does that make you feel when you know the work down the road paid off?

It’s an awesome feeling to think that I am playing a part in California’s attempt to combat the commercialization of ivory and stop the poaching crisis of these species in the wild. Right now, I am spending a large amount of my time developing and validating the lab’s ivory genetics assay. The goal of my work is to first, finish forensically validating the assay so it can withstand any courtroom scrutiny if it arises, and second, to publish my work in a peer-reviewed journal so that our lab, as well as other wildlife forensic labs throughout the world, can use the work I’ve done to support efforts in curbing wildlife trafficking. So far, I’ve been able to use the ivory genetics in a handful of ivory trafficking cases to further strengthen my report conclusions.

Were you one of those outdoorsy kids that love everything about the woods and animals?

Not particularly. I grew up going camping every summer for a few weeks, but I grew up in the city. I’m not a huge outdoorsman, but I dabble in hunting (turkey and dove) and a little fishing.

Some people might find it ironic that your job is to study ways to preserve wildlife, but you also get enjoyment out of hunting and fishing.

My work helps stamp out poaching, which is the illegal and unethical take of our natural resources. But legal, ethical hunting and fishing aren’t inherently bad, and in fact, are very beneficial. Responsible hunters and anglers make enormous contributions to conservation efforts worldwide. Conservation has many sides -- there are things we can do in the lab to preserve a species, but much of CDFW’s work is funded and supported by hunters’ and anglers’ license and tag fees.

If you weren’t in the science world, what’s the ideal job to have?

To this day, I’m waiting to win the lottery (because) I’d love to be an owner, worker, or bartender of a tiki bar on the beaches of Hawaii. Yep, a tiki bar on the beach, making mai tais and lava flows.

CDFW Photos. Top Photo: Forensic Specialist Kelly Carrothers tests tusk samples at the CDFW Wildlife Forensics Lab, in Sacramento

Montalvo collecting samples at an oil spill in the Huntington Beach channel


Quagga mussels found in Lake Mead


New Zealand mudsnails found at the Lower Feather River


Montalvo working a spill in the Oakland Harbor

Environmental Scientist Angie Montalvo is the aquatic invasive species (AIS) regional coordinator for CDFW’s North Central Region. Her job is to ensure that invasive species – including quagga and zebra mussels, snails, crabs, clams, fish and aquatic plants – don’t find their way into bodies of water in the region.

Montalvo graduated from the University of California, Davis, with degrees in biological sciences and behavioral psychology. In 1996, she was hired as a scientific aid in CDFW’s Aquatic Bioassessment Laboratory. She was hired as a full-time scientist in 1998 and spent about 15 years working for CDFW’s Office of Spill Prevention and Response (OSPR) on issues involving statewide pollution response, natural resource damage assessment and biological monitoring for macroinvertebrates. Through her work at OSPR she got to know the North Central Region, which helped earn her a promotion in 2013 as the region’s lead AIS coordinator.

What inspired you to become a scientist?

I’ve always been interested in the environment and being outdoors, and I wanted to see positive change for the environment. I always envisioned myself doing a great deal of field work because I enjoy it immensely, and I wanted to be a voice for the natural resources in our state. I developed my interest in AIS while at the Aquatic Bioassessment Lab and while working for OSPR. At OSPR, the focal point was protecting the state’s natural resources from damages due to various pollutants. My current job is somewhat similar, but I am protecting our natural resources from the impacts of introduced AIS.

Tell us more about your role at CDFW?

My work is focused on aquatic biology, mostly dealing with inland, freshwater issues. Currently, there are no waters infested with quagga or zebra mussels within my region, so my focus is on prevention and monitoring. I conduct a lot of monitoring of waterbodies where the risk of introduction and establishment for quagga and zebra mussels falls within the moderate to high range or is unknown. I typically conduct field sampling three to four days per week between late March through November, depending on weather conditions. I monitor for other invasive species as well, including the New Zealand mudsnail, Asian clam and invasive aquatic plants such as hydrilla and Eurasian watermilfoil. Asian clams were introduced into California roughly 40 years ago and have spread from low elevation to high elevation waters. New Zealand mudsnails were introduced into California’s streams about 20 years ago and continue to spread throughout the state.

Another important part of my job is the inspection of watercraft that have entered California from other states. It’s common for people to purchase boats from out of state that have been launched in infested waterbodies. Watercraft entering California are checked while coming across state lines at a California Department of Food and Agriculture inspection station. Food and Ag staff will contact me if they quarantine a watercraft for invasive mussels or other AIS, and I will then reach out to the owner to arrange for an inspection.

Depending on the size of the watercraft, it can take anywhere from 30 minutes to several hours to complete a thorough inspection. I can usually identify quagga and zebra mussels visually. However, if I anticipate a difficult inspection — for example, a houseboat with a lot of small components to search — I reach out to our wildlife officers and their mussel detection dogs. These K9s are trained to detect by scent and can find things that I might not see. I’ve worked with the mussel detection K9s at least half a dozen times and it has worked out very well.

Decontamination of vessels involves using a high-pressure hot washer that can reach water temperatures of more than 160 degrees. I usually conduct follow-up inspections as well. Watercraft aren’t released until there are no remnants of quagga/zebra mussels or other AIS observed.

Why is it important to monitor for aquatic invasive species?

Unfortunately, once you have an infestation – for example, of quagga mussels – you can never eradicate them from a waterbody. They change the water quality and infrastructure of the ecosystem. The infestation results in a build-up or layers of mussels in the ecosystem, which can deplete the water body of nutrients and cause clogging and filtering issues. Not only do invasives alter the ecosystem, but they can affect fisheries, water delivery and recreational opportunities. Trying to address these issues after an infestation can cost many millions of dollars. Prevention, monitoring and education are crucial.

What has been your biggest career accomplishment so far?

I’ve worked on major oil spill incidents like Cosco Busan, the BP Gulf spill and others, which have all been major accomplishments and unique experiences.

Currently, the major accomplishment is there are no waters infested with quagga or zebra mussels within my region. I attribute this success to CDFW’s dedication to practicing the best sampling methodologies, continuing to improve and standardize its statewide program and having a great public outreach and education program.

We’ve had good success with outreach. For example, we have a campaign called “Clean, Drain and Dry” to get boaters up to speed on what they can do to prevent the spread of invasive mussels and other AIS. We strongly encourage boaters to clean, drain and dry their motorized and non-motorized boats and any equipment that comes in contact with a waterbody. We try to make sure boaters are aware that that their boats can be subject to screening or inspections prior to launching at a waterbody. Based on feedback and what I’ve seen, the outreach does translate. Boaters are more familiar with invasives and following proactive steps to preventing the spread of AIS.

In addition to your work with AIS, you also serve as the lead environmental responder when there’s an inland pollution incident. What does that entail?

As part of the region’s Inland Pollution Response Support team, I respond to discharge incidents from sources like wastewater treatment plants, asphalt or cement contamination, vegetable oil and wine waste. When there is a discharge or spill incident, I typically work with wildlife officers and other agencies in an incident command setting. I collect samples to assess the extent of the impact. For example, with a sediment incident, I determine the volume of sediment within the waterbody, extent of injury to the biological and physical habitats. If the containment is chlorine, I collect field water samples to determine the percent chlorine level. My role as a spill responder is not directly connected to my work with AIS, but if I am out responding to a spill, then I will document any non-native species.

What advice do you have for young people who are considering careers in science or natural resources?

I would say follow your passion and do what you enjoy. It can be difficult to get a job in environmental science or in the field of aquatic biology, so be proactive and start volunteering early. Applying for a position as a scientific aid is very helpful and don’t be afraid to move around to different departments or groups to get a sense of what you enjoy and learn valuable field experience.

CDFW Photos. Top Photo: Environmental Scientist Angie Montalvo conducting an aquatic invasive species survey at a reservoir near Lake Tahoe

Media Contact:
Ken Paglia, CDFW Communications, (916) 322-8958
 

As an 11-year wildlife biologist for CDFW’s Central Region, Nathan was involved in several captures, collars and relocations of California’s native tule elk.


Away from work, Nathan enjoys preparing wild game. Here he makes sausage out of wild duck.

Nathan Graveline was hired as CDFW’s Big Game Program supervisor in March 2019 after spending his entire career in the field as a wildlife biologist. Now based in Sacramento, Nathan supervises a team of headquarters biologists and research staff who support California’s deer, elk, pronghorn and desert bighorn sheep conservation and management programs.

Nathan spent the previous 11 years as CDFW’s wildlife biologist for Mariposa and Tuolumne counties. He joined CDFW full time as a deer biologist in 2001 after working as a seasonal aid for three summers at the Mendota Wildlife Area and later served as a scientific aid for CDFW’s upland game bird and deer programs.

Nathan was born and raised in Fresno and holds a degree in forestry and wildlife management from Cal Poly San Luis Obispo.

It’s still deer season in some parts of the state. How would you assess the status of California’s deer herds?

I think most of our populations are fairly stable. There are certainly areas that we are concerned about. The X zones – X12, X9a and X9b – still have not recovered from the harsh winter in 2016. We were hoping to see some recovery there and to potentially increase tags again. But the data are just not supporting increasing tags. The good news is that we have data to make those kinds of assessments.

Across what we call our opportunity zones – the A Zone and D zones – things don’t change that much in terms of populations and hunter success.

Is it an oversimplification to say that resident deer herds are doing well and migratory deer herds are not?

Probably not. We have two species of deer in California – Columbian black-tailed deer on the coast and mule deer in the eastern part of the state. And there are some hybrids in between.

We’ve done fecal DNA analysis on black-tailed deer in Marin County, for instance, and we got population densities that were through the roof, as high as 30 deer or more per square kilometer. Now, deer hunting is limited in most parts of Marin County, there are very few predators, and food is available year-round because people have yards with plants that supply a food source. And that’s similar to what we see in the Sierra foothill communities. Predation is low, you have more water, more forage and the deer populations tend to be more stable. Even in a drought, people still have yards that can provide food and water.

By contrast, our migratory mule deer herds are subject to every possible environmental condition plus other factors – development, highways, human recreation – that can impact habitat corridors and migration.

Are you a deer hunter?

I am. I think I shot my first deer in 2004. It took me a couple of years to get the first one. I’ve been consistently deer hunting since then. I try to feed my family with venison mostly. We don’t buy beef. Venison is our primary meat source.

Some hunters are discouraged about the state of deer hunting in California. The general sense is it’s much harder than it used to be and much tougher to be successful compared to other states. Is there any advice or words of encouragement you can offer?

I think there is some really good hunting out there. We have an amazing amount of opportunity in California. We have a lot of over-the-counter tags (you can purchase without applying through a lottery), but that also means you have a lot of competition in the field. So just thinking outside of the box with tactics is always a good thing.

Take advantage of our wilderness areas. We have a lot of wilderness in this state – roadless areas, federally designated wilderness. Hunters who are willing to get off the beaten path a little bit can find some quiet out there where they can hunt and potentially be by themselves. I don’t think hunters use optics as much as they could, especially on the east side and areas that are more open.

Take advantage of the gear that we have now. The technology has changed so much. It used to be that rangefinders would work out to 400 yards. Now they can range a mile. It’s just amazing. Optics in general are better than they used to be. There are a lot more long-range rifle options out there today, although that takes some practice to become proficient. It’s not something you just pick up and do.

You’re saying California deer hunters need to hunt differently than they did 10 or 20 years ago?

I think so. I hunted Zone X12 (Mono County) two years ago with my dad. We didn’t do a lot of hiking. We did some hikes, but we were primarily road hunting. We saw a ton of deer, and it was because we would stop and glass. We’d get the spotting scope out and just look. I was shocked at how many deer we saw from the roads.

A lot of other hunters were just driving past us – dusting us out. They’d complain in the restaurant later that evening that they didn’t see anything. I think it’s a matter of changing the way we do things. Slowing down. All the quads and mules and side-by-sides that hunters use – you miss a lot of stuff when you use those.

Mountain lions and bears are sore subjects for many deer hunters. To what degree are bears and mountain lions impacting California’s deer herds?

Habitat is the biggest limiting factor for wildlife. But when you have populations that are struggling – for whatever reason, maybe the habitat is not optimal – things like disease and predation can prevent those populations from rebounding.

We all know lions kill a lot of deer. Theoretically, though, if you have quality habitat, the deer populations should be able to handle that and you’re going to have cyclical population cycles among predators and prey.

Maybe the suburban deer issue has shifted some of the balance and lion populations are higher than we might normally see because those lions are now living on the suburban edge. And when the deer aren’t there, the lions can eat goats and sheep – and they do sometimes. And when the deer return in the winter, lions have plenty of deer to feed on. It’s a possibility and something we might discover as we continue collecting data on mountain lion populations.

We do know that bears prey on fawns in their summer range and they also steal mountain lion kills. Those lions then have to go out and kill more deer than they otherwise would. We’ve got that documented. We don’t have any scientific papers published on it as far as I know, but we’ve got lots of camera data to support that. We’ve had GPS-collared deer that were confirmed lion kills, we set up a trail camera, and a bear comes along and steals that deer carcass. It’s a concern, for sure.

To what extent can CDFW improve deer hunting in California?

I think our best option is to work with the land management agencies – BLM, the Forest Service – to try and influence the habitat side of things. I think we can provide them with data on migration routes so that if they are going to be doing a big project in an area we can use that data to help inform that project and undertake appropriate treatments. If it’s winter range, we need to emphasize the importance of winter range habitat for deer and how we can improve that range. We have good relationships with those agencies. But it’s just like anything else, we can always do a better job of communicating, using and sharing the information that we have.

And then we can control to some level the quality of hunting based on our data and the number of deer tags we issue. Typically with the X zones, we try and manage more for a quality hunt. The A, C and D zones are more about opportunity.

So many of our deer seasons in California start earlier than many other states. Is there any discussion to move deer seasons later in the year, closer to the rut, when hunter success would be higher?

The general consensus among deer biologists in the state is that the herds cannot sustain the added pressure of hunting during the rut. If we were to do that, we’d have to reduce tag numbers dramatically. And that’s the tradeoff. If you really want to have late hunts, you have to issue significantly fewer tags.

What about the resident herds that are stable or growing? Are there opportunities to create some additional deer hunts for the public?

Yes, we are looking at the Central Valley river corridors – the Merced River, the San Joaquin River, the Tuolumne River-- and some of the national wildlife refuges and our state wildlife areas nearby where we see deer numbers increasing. Those would be A Zone hunts. The U.S. Fish and Wildlife Service is interested in doing some deer population assessments and potentially holding hunts on their land, and we are coordinating with them. Some of our Merced County wildlife areas – Los Banos, North Grasslands – would be good candidates to hold deer hunts – at least youth hunts. That would require some regulatory changes to permit deer as a species of take, but we are definitely looking at that.

Tell us something about yourself many people would be surprised to learn.

I do a lot of foraging – mushroom hunting and general forest foraging. I love cooking. I love to make charcuterie, sausages and cured meats with wild game. There is a lot that goes into harvesting a deer or an elk or whatever species it is – a lot of time and money and personal effort and all of that. So to me, honoring that wild animal and turning that wild game into something really special – something more than what you’d do with a chunk of beef – is important.

CDFW Photo. Top Photo: Photo Captions: Nathan Graveline with the X12 Zone 3x3 buck he harvested in 2017 with his father.