This week, Emily Dai, representing UCSC’s Macrocosm, met up virtually with Traci Kendall, who shared her experience and unique job. Traci Kendall is a dolphin trainer who works at the Long Marine Lab at UCSC under Dr. Terrie Williams.
[This interview has been edited and condensed for clarity.]
Macrocosm: Could you introduce yourself, your profession, how you got into this field, and why you chose this specific field over other forms of conservation?
Traci Kendall: Sure! So my name is Traci Kendall, and I got into this field because, as a child in grade school, I went to another facility that is very similar to the one I work at — a marine lab in Southern California at Dana Point. When I went there, it was called the Dana Point Marine Lab, but now it's called the Ocean Institute. I got to do some hands-on things with some fish dissections and plankton trawls and absolutely loved it. I fell in love with Marine Biology from that day forward. So I decided, at ten, that I wanted to be a marine biologist and got my degree in Basic Biology because the school I went to did not specialize in marine science. But I’m actually very glad that I got a General Biology degree because it gives me a much broader degree of knowledge. So, from there, I started volunteering here on the marine mammal physiology project, thinking I was just going to do it for a year or whatever…(spoiler: it was not just “whatever”.) Now, twenty-four and a half years later, I’m still here, so I think I sort of fell into it. I also did an internship when I was in college with this US Navy Marine Mammal Program, and it was the first time that I recognized that you could train marine mammals for research, and it was really appealing to me because I loved the academic side of it and doing something conservation based. For me, that’s very rewarding.
M: What in particular do you research about marine mammals?
TK: So at the lab that I work in under Dr. Terrie Williams—she’s a comparative physiologist—we largely look at the physiology of the animals. Essentially, we’re looking at what unique adaptations marine mammals have that allow them to survive in the marine environment that they live in: what kinds of adaptation do they have in terms of their heart rate because being a marine mammal that has to hold their breath while doing things like exercising and finding food creates a unique challenge for them. So, we want to know how their heart is able to maintain beating and performing while they’re holding their breath. We also do a lot of metabolism measurements, where we’re trying to figure out how many calories these animals need to intake to do different types of activities, whether that’s resting, doing high-energy swim, a dive and a slow swim, or a dive and a rest — basically putting together what a dolphin does in the wild on a daily basis and then figuring out how many calories an animal needs on a daily basis to survive in the wild. So that's what we're trying to do: get all of the pieces of the information and apply it back to wild animals. Therefore, if we find that there's a particular population of animals that is struggling because they don't have enough food resources, we can pass that information on to legislators and make sure that rules are put in place so that those animals can have enough food to survive. Obviously, we humans can get our food from other places but the animals from the ocean can’t.
M: Approximately how many marine mammals do you take in each year and why do you take them in?
KT: Although we have done some rehabilitation work with animals in the past, the animals that we currently have are not releasable. These animals will live in aquarium settings for the rest of their lives. We have one dolphin that was born in human care, so he's never lived in the wild his entire life and wouldn't be able to acclimate because he has never seen the wild. It would probably be a really scary place to him. We have one dolphin that did live in the wild for a very short time but he, for whatever reason, got separated from his mom and became stranded as a really young calf. He didn't know how to find food on his own, so the government deemed him non-releasable from that day forward. Next, we have a Hawaiian monk seal that we have here currently who had lived in the wild for a good amount of time, but he was not interacting well with other Hawaiian monk seals. When you have a very endangered population and there is an animal that is having an impact on the endangered population, it's not a good mix for them to continue living in the wild. So, he was actually brought in to try to help save some of the animals that were living in areas where he was living as well. One of the other Hawaiian monk seals that has lived here in the past was stranded when he was 24 hours old—his mom abandoned him—and he also has only ever been raised by people so he wouldn't know how to live in the wild either. So that’s basically what we have right now: the two bottlenose dolphins and the Hawaiian monk seal. We have had other species in the past as well, such as sea otters, but that’s all we have at this moment.
M: I’m quite surprised that there are conservation methods when you take in animals out of an environment to try to protect the rest of the population.
KT: Yeah, it’s kind of a unique way of thinking, and, in fact, when the government NOAA took that monk seal out of the wild, their initial response with him was to euthanize him to help reduce the impact that he was having on the population. Then, at the last minute, they asked us if we’d like to take him in and do some conservation work with him since we've had a monk seal before. We said “Yes, absolutely,” and I have to say it was probably one of the best decisions that we’ve ever made because he's been an absolutely amazing animal. I think people sometimes get this misconception that an animal that has been aggressive in the wild is going to be aggressive with people. That typically does not seem to be the case. He has been very respectful to people and he's been just a great animal in general.
M: What is one aspect of your job that people wouldn’t usually expect?
KT: I think people have a very glamorous view of working with marine mammals, and although there are components to it that are a lot of fun, it also is extremely hard work and there's a lot of labor involved. There's especially a ton of cleaning—for example, bleaching because we have to disinfect and clean all of the food preparation areas that we use every single day. Also, although it is fun to be around marine mammals, we also have to withstand all types of weather for our research—whether it’s raining, windy, or whatever the outdoor elements are. We’re in it all day long, every day, at Christmas or New Year's or whatever; we’re here all the time: 365 days a year.
M: So, what’s your favorite part of your job and your field?
KT: For me, I think my favorite part, in addition to being able to interact with the animals, is just the aspect of coming up with new ideas and exploring the unknown. When my boss Dr. Williams comes up with an idea that she wants to investigate, I have to find creative ways to train the animals to do that task. It's sort of like a puzzle where you're trying to figure out what's the best way to train this animal. We have to take into consideration how to get the information we really want and have them do it cooperatively, because if they’re in a situation where they’re forced into it, that's not going to give you reliable data. We want the data to be as reliable as possible and the animals to be as comfortable as possible.
M: So how can you tell if the animal is uncomfortable, and how can you train them for research?
KT: In order to know if the animal is comfortable, you basically have to know your animals and get to know what is normal for the species in terms of their natural history so you can get a good idea of what species show what as signs of stress. So first you have to get to know the animal’s background in terms of their species and then you also have to learn the background of the individual animal because, just like humans, every single animal has their own unique personalities and the things that make them unique, and so we have to get to know them that way as well. That's what we use to make sure that they're comfortable in their environment and we’re not doing anything that’s going to cost them an abnormal amount of stress. Obviously—I’m sure you’ve experienced this too—there's always going to be some components of learning that are stressful, but as long as it's a good type of stress and a type of stress that's challenging them to try harder and not to just completely shut down, then we consider that to be an acceptable small level of challenge for the animal.
So the way that we train the animals to do the different types of tasks is a system of positive reinforcement training that's called bridge and target training. First, we teach the animal some signal that tells them that they've done a behavior correctly: when I was doing the demo for Cosmos, you probably saw that I had a whistle that I was using for the dolphins. With the monk seal I was saying “Good” but I was saying it with a high-pitch so that it pinpoints exactly when the behavior is done correctly. We teach them that the behavior has some significance basically just by feeding them fish over and over and over while we're making the sound—the whistle or if it's the same “Good” or sometimes in dog training they use a little clicker. This basically teaches the animal that the sound means something good and you do that by pairing it with primary reinforcement.
The second component of positive reinforcement is the target component: once you’ve conditioned a signal that means that they've done something correctly, you would then train them a “target”. For our purposes, it can be a number of things: it can be your hand or a colored piece of plastic, and since animals are typically curious and lead with their faces whenever they go in a certain direction, you would train them to touch their body part, in this case their face, to the object. Once they do that, you can now use the signal that you've conditioned in positive reinforcement to tell them “Yes, that's what I want.” Once they learn the target, you can use it to shape many types of different behaviors by having them follow the target, touch it, and then touch different types of body parts to it until they can do basically every behavior.
The only exception to that—the only thing you can’t target train—is vocals because you can’t physically get a vocal out of an animal. You just have to wait for them to make a sound. So for that is another type of training that’s called scan and capture, where you just wait until the animal makes the sound and then you give them the signal that means “Yes, I like that” and feed them. Over time they start to learn “Oh, you're giving me primary reinforcement” because I made the sound. Then we put it on an arbitrary signal that doesn't really mean anything to us, but, sort of like sign language, it means something to the animals, and each behavior has its own signal that means “Do that particular behavior.”
M: That sounds quite time intensive.
KT: Yeah, and a lot of people, when they see the animals, they always comment “I wish my dog was this well trained,” and I always tell them this: If you spent eight hours a day training your dog, I guarantee you your dog would be this well-trained or more. However, nobody spends that many hours a day training animals with the exception of animal professionals.
M: What is your favorite memory from working at the Long Marine Lab?
KT: Oh wow, that is a fantastic question. I don't know if this counts as one particular memory, but I have one favorite animal that I worked with. His name was Primo, and he was one of the first dolphins I worked with when I started volunteering here. I had the privilege of working with him for 22 and 1/2 years, which is a really long amount of time. Unfortunately, he just passed away a couple of years ago. However, he lived to be 40, which is a really long life for a dolphin. He taught me a lot because he was a very patient animal, but also because he was extremely stubborn. He taught me how to be a better trainer in general, I would say, just by learning how to work with him and not let him be so stubborn that he refused to do things. I got a lot of appreciation out of watching him train people because he was so patient, and I really think he got a lot out of that human-animal connection to the point that it was something that he enjoyed just as much as we as humans enjoy working with him. It was really wonderful to see an animal with such a great work ethic.
M: So what advice would you give to someone who wants to go into a Marine Biology career?
KT: Well, first off, I would give them the advice that schooling is obviously very helpful; there's really not a lot of jobs in this field that you can do without a college degree. The next thing I would say is to be prepared to do a lot of volunteering because the thing about this field is that you don't make a lot of money. So, one of the things that people use to see if you'll be able to make it in this industry is to have you volunteer your time, and if you can show that you're willing to do all this hard manual labor for free, then that is sort of a building block to getting a career in marine biology down the road.
M: It sounds like a scenario where you pursue your dreams instead of the common career choices such as being a doctor or a lawyer.
KT: Yeah, absolutely, and I think a lot of people who have volunteered here in the past that have wanted to do this for the rest of their life, whether it's because of family pressure or just other life pressures, they don't pursue it primarily because of the low income. I think a lot of families, parents especially, want their kids to succeed, and they see success as being something where you can be a nurse or a lawyer to make a lot of money and this is not one of those fields. But it's definitely a job where I feel like I'm never coming to work. I feel like I am doing something that I'd love to do every single day, and it has basically shaped my entire life. When I was younger, I thought that I would have a family and have kids, but these guys have become my family and I don't have kids. There are trade-offs, but I think for me it's been worth it every step of the way.
M: Our last question is a “just for fun question,” so what’s the weirdest food you’ve eaten?
KT: I mean it's not that weird, because I've had things that some people might think are weird and other people think it's totally normal, but one of the things I remember eating as a kid that my grandpa gave me is cow tongue. I think from a texture standpoint it’s really kind of strange. From what I remember, since I was pretty young, it’s got this squishy, buttery kind of consistency to it. I don't remember what it tasted like; I just remembered that it was the consistency was very like a kind of melts in your mouth sort of.
M: Well, that sounds quite interesting. That’s all the questions I have, so thanks for the interview!
KT: Thank you. Have a great rest of your day! - Emily Dai
Discovery Lecture: Circadian Rhythms
Have you ever wondered how our body knows when it is time to wake up and go to sleep, and what systems control this process? Or why do our energy levels differ so greatly throughout the day? Why do some people tend to be early birds, and others night owls? And, would humans still function on a 24-hour basis, should we travel to another solar system? All these questions are related to circadian rhythms - the internal clocks in all living organisms that synchronize to Earth’s daily rotation.
This Monday, Dr. Carrie Partch, professor in the UCSC Department of Biochemistry and Chemistry and Principal Investigator at Partch Lab, UCSC, introduced the students of COSMOS to circadian rhythms, including the factors they play in controlling biology and how they function at the molecular level.
Prof. Partch began her lecture by explaining that all terrestrial life is synchronized to Earth’s 24-hour daily rotation. Over time, species ranging from single celled organisms to plants, insects, and animals have evolved circadian rhythms in response to the relentlesscycle of light and dark. These internal clocks are necessary for organisms to predict environmental changes - such as the movement of the sun.
Circadian rhythms – named after the Latin phrase for “a day”, circa diem – control much of our biology. By triggering the release of hormones and changes in gene expression, they control the timing of your daily life in ways you may not expect. For example, your circadian clock controls your body temperature, blood pressure, concentration levels, physical performance, DNA repair, and melatonin levels, throughout the day.
However, you may be asking yourself: how does life synchronize to Earth’s daily rotation in the first place? How does your body know when the sun sets in order to cue the release of melatonin? Scientists began seeking answers to these questions nearly 100 years ago in places you’d least expect. A popular study foundational to our modern understanding of circadian rhythms was conducted by Bruce Richardson & Nathaniel Kleitman in Mammoth Cave, Kentucky. (Why Mammoth Cave, you may be asking? Well, Mammoth Cave was simply the darkest, most isolated location they could find.) The purpose of this experiment was to determine whether people have a 24-hour clock hardwired into their biology, and they sought to answer this question by simulating a 28-hour day. With the sun blocked out by the caves thick walls, all light was under their control. In this controlled light environment, volunteers were exposed to 14 hours of light per ‘day’ and 14 hours of darkness per ‘night’. Researchers sought to determine whether this lifestyle was sustainable over long periods of time. After weeks of living and sleeping in isolated tunnels, it was determined that humans could not adjust to a 28-hour clock, even though all uncontrolled sources of light were eliminated. From this experiment, researchers and scientists concluded that human anatomy is built to operate on a 24-hour cycle, and even shifting that by an hour can strain our bodies.
While it has been proven that circadian rhythms aren’t entirely dependent upon the presence or absence of the sun on a 24-hour schedule, that is not to say that circadian rhythms don’t adjust to differing light patterns. For example, when you take a plane from the USA to Europe, you essentially “out race” the sun. By doing this, your circadian rhythm is forced to adjust a certain amount of hours. For instance, if you depart at 1:00 PM from the San Francisco airport and proceed to fly 11 hours to Frankfurt, Germany where you arrive at 9:00 AM local time (or 12:00 AM SF time), your body must adjust to a completely different time zone. Your circadian rhythm most likely produced a good amount of melatonin during your flight once it approached sunset in your local time zone, but once you landed in Germany, the overload of photons and sense of daylight confused your circadian system. This phenomenon is known as “jet lag”, and results from circadian misalignment: when your internal clock and the external conditions are not aligned.
While jet lag may be an uncomfortable, groggy experience, our bodies take active measures to adjust and realign. Your suprachiasmatic nucleus (SCN), located in the brain’s hypothalamus, is the only member of the circadian clock that gets direct input from exterior conditions. Once it detects certain environmental changes (such as a decrease in the amount of photons/sunlight), it communicates these changes with the rest of your body through metabolites and hormones. An interesting fact is that once a signal is distributed by the SCN, some tissues receive and adapt to this signal longer than others. For example, the liver adapts quite quickly to these signals (explaining why it’s difficult to refuse dinner after a long flight, regardless of several meals being served on the trip). After about a week, all the bodily tissue has adapted to the local timing and is functioning normally (coincidentally on time for your flight back home).
However, out-racing the sun is not the only way to throw off your circadian clock. In fact, the light emitted from screens past sunset has been proven to trick your circadian clock into thinking it is still daylight. As a result, melatonin production decreases up to 60%, REM sleep/sleep quality is decreased, and morning alertness is reduced. Because of this fact, it is crucial that you resist the temptation to scroll through Tik Tok or play video games right before bed (especially if you’re looking to grow those extra few inches!). If you aren’t convinced quite yet, Prof. Partch also pointed out that your circadian rhythm intimately controls your metabolism in order to anticipate when you might eat next. Various studies with mice showed that eating as little as 20% of your diet past sunset --when your body expects you to be asleep-- can severely slow your metabolism. In these studies, nocturnal mice who ate the same diet/calories at daytime had a significantly larger body fat percentage than mice who ate during the nighttime. This also applies to humans: disruption of the circadian clock has been linked to diabetes and similar metabolic syndromes.
Prof. Partch then went over various studies involving firefly bioluminescence and drosophila flies that proved roughly 40% of the human genome is controlled by circadian clock (meaning it is produced either in the day or nighttime) and that the circadian clock is relevant at the scale of a single cell. We also learned that through these studies, scientists have been able to track specific mutations that influence the circadian rhythm, such as the “night owl” mutation. This mutation, known officially as Delayed Sleep Phase Disorder, is responsible for causing severely disrupted sleep schedules in which the patient goes to bed at inconsistent times, often early in the morning and for only a few hours at a time, consequentially napping during the daytime. This mutation lengthens the circadian period, therefore delaying the release of melatonin.
Recent research has looked into controlling the circadian rhythm: the premise is that a small molecule will bind into the pocket of the CRY protein, therefore restoring the clock back to 24 hours. This will allow those with the “Night Owl” mutation to maintain a healthy sleep schedule and could also help humans adjust to different planet cycles in future space travel.
Prof. Partch concluded her lecture by describing what work in a biochemistry lab looks like, not failing to mention the large amount of cleaning and collaboration that happens behind the scenes. She also went over various ways to build a career in science.
Prof. Partch’s captivating presentation on circadian rhythms, their effect on daily life, and their structure on the level of individual proteins has provided us all with a refreshing perspective on the biological processes that play a foundational and often misunderstood role in life on Earth. Her firsthand experience working in the biochemistry field and the intimate advice that was shared have inspired the students of COSMOS, and provided us with a new level of appreciation and understanding for the countless scientists and researchers working hard to understand biological processes across the globe. - Astra Tulac
Discovery Lecture: Removing pollutants from water with inorganic materials