Today's Voices of Conservation Science
Today's Voices of Conservation Science
Parker Levinson — Counting Pups in Antarctica: Understanding Factors Influencing Weddell Seals
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Parker Levinson, a graduate student in the Department of Ecology at Montana State University, discusses her passion for animals, love for field research, and her research on Weddell seals.
Welcome to today's Voices of Conservation Science, where we talk to people doing science that's then used to conserve natural resources. I'm your host, Andrea Litt. And my guest today is Parker Levinson. She's a graduate student in the Department of Ecology at Montana State University. Hey Parker, how's it going? I'm great. How are you? I'm doing well. Thanks for joining us. We're here in this studio Zoom space doing our interviews, which is always a fun, fun place to be.
SPEAKER_00It's great to be here. It's a learning experience for all of us.
SPEAKER_01Why don't we get started by just having you give us a little bit of background about you? Where did you grow up? Um, where'd you go to school? And then we'll get into your path and your research as we move forward.
SPEAKER_00I grew up in Monterey, California, so Central Coast, California. Um, and I grew up, you know, going to the beach and enjoying the natural world that way. Um and then I took a gap year before going to university. I kind of wanted to figure out what I wanted to do with my life. And then I ended up going to Northwestern University in Chicago, where I double-majored in environmental sciences and African studies. After graduating, I worked various wildlife tech positions around the world and started working for Dr. Jay Rotella, who eventually offered me a master's position with him. And I'm now getting my master's with Jay.
SPEAKER_01So there's a lot in there I want to uh uh chat about because yeah, lots of cool things in your in your path just in the background. So you said you did a gap year. I'm curious what you ended up doing during that gap year before you headed off to to Illinois to Northwestern.
SPEAKER_00I had the most incredible gap year experience. I actually got connected with some uh researchers at Wake Forest University who were looking for a field technician. And so I spent five or six months helping them out in the Galapagos doing population demography work. And then um, in between seasons, I spent a lot of time by myself traveling in South America.
SPEAKER_01So this is before you even went to college. I mean, that's that's pretty amazing to start with.
SPEAKER_00Yeah, I was really fortunate um that I was in the right place at the right time and knew some folks who needed help and got really great hands-on experience before I went to college.
SPEAKER_01That's really cool. Um, and you said you you got this double major in environmental sciences and and African studies. Um, I I suspect I have a sense of what went along, went into your environmental sciences degree, but tell me a little bit about this African studies piece.
SPEAKER_00Honestly, it was just because I was intellectually curious. Northwestern has one of the best African studies libraries in the US. And one of my professors told me that. And I thought I should take advantage of it. And so I just threw in some extra classes and did a lot of African literature and African history and um got a degree with that. And my time, my thinking was maybe I'll go into the conservation sphere in Africa and it will be useful to have my life a sense taken other turns.
SPEAKER_01That was my initial thought. Because it does. But yeah, I mean, I it still already sounds like you had a pretty clear um like you had a vision that that conservation was gonna be, was gonna be your path. And I'm curious how you figured out that one, that it could be a career, and two, that it was a career that you would be interested in pursuing.
SPEAKER_00It definitely is not what I thought my career was gonna be. I love growing up, I loved being around animals and I wanted to be a vet. And so I would go to the vet clinic and help out at like spays and neuters. And and then I kind of got really interested in wildlife, and I was like, well, I'll just be a wildlife vet because then I can still be around wildlife and still handle them. But really, it was my gap year when I worked as a field technician in the Galapagos, where I just fell in love with um with field work and and with sort of more of the research that goes along with that. And then once I got to Northwestern, my one of my professors there said that I could do everything I wanted to do with wildlife without actually having to get a vet degree. And so then I just thought, well, why waste four more years of school if I can, you know, starting do what I want to do right off the bat. Um yeah, and the other thing is Northwestern doesn't have a great wildlife program. They definitely have a lot more of an environmental or earth sciences program. And so I was trying to figure out classes that I could take that would set me up for success, even if they weren't the traditional courses that people have in this field.
SPEAKER_01Yeah, it's it's it's neat to that you had this idea of things that you were interested in, and you're like, oh, well, I can just do it that way and and pursue it in that in that way, and that's and that's cool. Um, you mentioned in your intro that you had had this suite of wildlife jobs and you said around the world, which not everybody gets to say. Um so I'm curious, give us a give us a little highlight reel of the places that you worked during that time and and maybe some of the species that you were that you were working on.
SPEAKER_00Yeah, it was probably maybe three or four years between my undergraduate degree and going into grad school at MSU. Um, and in that time, I worked with sea turtles and in the West in the coast of West Africa. Um, I worked in with wolves and other species in Washington. Um I'd also that was the first time I went to Antarctica working with penguins before I even got connected with Jay and with seals. So those are the sort of the highlights and kind of everything I did. I didn't do anything else beside that.
SPEAKER_01That's uh that's amazing. And and we're giving a little highlight to what we'll get to with your with your research, the the preview of of where you're where you're working and what you're working on, and we'll circle back to that. Um what what was what do you think was helpful for you in in securing that first position after after college? You know, especially knowing about you that you you had the Scalapagos experience before you even started college. Um, do you have any like things that you tips that you would share with with others of like how did you learn about that first position? How did you secure that first position? Because then that helps you string together the next, the next position and the next position and the next position as you build your network.
SPEAKER_00Yeah, you're exactly right. I feel like one position sort of snowballs into the next. And I was very fortunate that I already had um a position on my resume that showed that I could do remote field experience. And then when I was in college, I was doing independent research in the summers. And so that showed that I could work by myself and do independent research. And so I think I could leverage both of those traits and in applying for jobs after school. Um, and I basically just lived on Texas AM's wildlife job board. And anytime there's a job that sounded interesting to me that seemed like I had some skills that I could provide, but there was also a lot of room for me to grow at that position, I would apply for it. And there were many jobs I applied for and I didn't hear back. I didn't even hear that my application had been received. I had no idea. And after I don't know how many I applied for it, but I got an I got an interview for this one. And um actually I learned that I almost wasn't hired for it. I was, you know, a backup backup and ended up getting it and uh have a great relationship with my former boss and it all worked out. But I think there's so much luck that goes into this field, and you kind of just have to hope, put yourself out there and hope that something falls in place.
SPEAKER_01Yeah, I mean, you talked earlier about being in the right place at the right time, but that is in part of you putting yourself out there to be in that in that right place and and put and putting those applications out even after, you know, lots of not hearing lots of rejections. I'm not sure which is worst, honestly, is the not not even hearing whether the application was received or then finding out you didn't get the position um very directly.
SPEAKER_00And I also think there's something about how you can market yourself. And so I didn't have a lot of technician positions, but I could say, you know, look, I am a go-getter and I'm gonna try to, you know, I'm gonna learn as really fast. And here's an example of a class project I did in which I learned really fast and I learned these methods, or um I'm not, I haven't been to this location before, but here's a trip that I took with a friend that shows that I can, you know, travel or whatever that might be. And so even if you don't have the exact experience, if you can show that you have a, you know, a skill that's related to that, I think that's really helpful.
SPEAKER_01I think that's really excellent advice because it um particularly when people are getting started in this field, you know, you have to have experience to get experience, right? And and so when you're building that resume and building those that network, then um, you know, people go, I don't, I don't, I haven't done that, right? But but what you just described of like, well, you maybe have done that, but in a different environment or um in a in a different kind of job to say, you know, I do have leadership potential, or I have had to work independently, or I have had to pay attention to detail and demonstrating that and helping people see you and see how exactly you're qualified. I think that's great, great advice. Um, clearly you talked about some challenges, you know, the flinging many, many applications out into the void. You talked about um remote fieldwork. So some of the places that you've you've worked, you know, are challenging to get to and challenging to work on. Um, would you say those are some of the biggest challenges you've encountered, or or would you define, if you had to look back across your path, like what would you say your your your big hurdles were along the way?
SPEAKER_00I think one of the biggest hurdles for me honestly was getting the experience I needed. Northwestern is on the quarter system, and so we don't finish classes until end of June, which means that I wasn't able to apply for a lot of the um wildlife positions that are available in the summer in which you don't necessarily need to have skill, in which they hire a lot of people to gain those skills. And so I felt like I was at a disadvantage when I was graduating because I was competing against people that had three or four field tech positions on their resume. And I wasn't able to get any of those because of how my classes worked out. Um, and also Northwestern didn't have a wildlife program. So I haven't taken any wildlife course really, um, which I'm, you know, remedying now. But when you're applying for jobs and they want to make sure you you know about ecology and you know about small mammal trapping, trapping or whatever they might be requiring, I never got any of those. And I think how I tried to work around that was finding opportunities. And so I couldn't, I couldn't be part of a field crew, but I could conduct my own independent research on uh, you know, I worked with primates my first uh summer and they're not it was in a lab, but I was still, you know, handling animals and I was still showing that I can conduct research and finding those opportunities that I could then translate those skills later. Um, and then the yeah, the other remote field work is always a challenge. That's something I love doing. And so for me, it doesn't feel as much of a challenge, but just being away and out of communication from family and friends is really difficult. And it takes a lot of prep work to get ready for those seasons and to come back from them.
SPEAKER_01What do you think has been helpful in in you being successful and getting through those long, long periods of being disconnected from from your your normal day-to-day life?
SPEAKER_00A great community and a lot of practice. Um my yeah, my first job out of school, I defaulted on my credit card and my credit score tanked and I was in debt and I had no money and I was stranded. And I have learned to not do that. Um, and so if I'm gone for long periods of time, I have people check my bank account for me and I, you know, put extra money on my credit card. So in case there's a weird charge, I don't default on it. And um, I've spent a lot of time on the phone with, you know, credit agencies.
SPEAKER_01Yeah. Yeah. I mean, setting putting putting practices in place that allow you to work through those. And and that could be those practical things like finances, but also, yeah, being being disconnected from from your network of people. I mean, I think we are a lot more connected now, but still there are plenty of places where you you aren't. You just aren't connected in that community that you talked about. It sounds really important. Are there particular people that you feel like have helped you be successful in this path that you've had so far? Not necessarily just the remote fieldwork, but in general.
SPEAKER_00Yeah, I I think everyone I've worked with has helped me in some way. And um, either through networking or teaching me a skill, I do want to give a special thanks to uh Dr. Emily Tompkin and Dave Anderson, who were the first people who took a chance on me out of high school and and helped me work in the Galapagos. Um that's something that I know they didn't take lightly, and I feel really fortunate that they gave me the chance. And I hope to be able to pass that along at some point in my career because I would not be here without them, you know, showing me the ropes and teaching me about field work and about population conservation work.
SPEAKER_01I think for all of us, we have we have that person, or, or in your case, people that that took a chance on us when we were we were first first building our skill set and first building our network. And yeah, the idea of being able to pay that forward is a pretty exciting possibility um as we as we all grow in our careers. You're listening to today's voices of conservation science. Today I'm talking with Parker Levinson. She's a graduate student in the Department of Ecology at Montana State University. Okay, Parker, now is the time of the interview where we get we get to hear um about your study species. So before we talk about your your research questions, why don't you give us an introduction to what you work on and where you get to do that work?
SPEAKER_00I get to study weddle seals in Antarctica. And they're this amazing animal. Uh the females can be about a thousand pounds. And so this it's a large mammal that we get to work around. Um, and we study the population outside of McMurdo Station, which is the largest research base, American research base in Antarctica. The seal is known for its breath holding and dive capacity, so they can actually hold their breath up to 90 minutes, which is astounding. And so a lot of people are really interested in the physiology or what's going on in the body of these seals. The reason that I like studying them is because they're pretty docile and easily approachable on land. They don't have any predators on land. And so, as a researcher, you're actually able to walk up to them pretty easily and not fear for your safety. We have safety measures in place, but in general, it's pretty easy to walk up to them and collect the data that we're interested in collecting and then move on to the next one. And the population has um, you know, more than a thousand individuals. And so I think it's pretty rare in the wild to be able to encounter that many large mammals in your in your study system. And so I feel very fortunate to be able to interact with that many large mammals every time I go down there to collect data.
SPEAKER_01It is a pretty remarkable um thing. I I have been privileged enough to get to spend some time working with um with white seals and helping on this this project that you're part of and and being in Antarctica. And and the idea that you can walk up to a giant thousand-pound mammal and that being a reasonable thing to do. Um, you know, and and that's for people, people listening. We live in the Greater Yellowstone ecosystem where there are grizzly bears and other very large mammals that one, you wouldn't see a thousand of them in a in a small space, and you also wouldn't walk up to them and and feel reasonably okay about your safety. So it is it is kind of a crazy experience, and they are a really remarkable animal with all the adaptations that they have for for living in the water and then hauling out on the on the land, which which correct me if I'm wrong, the land is mostly ice, right?
SPEAKER_00Correct. The land is all sea ice or frozen ocean. Um, it's more than a meter thick normally, and so it feels like land. You can kind of operate like you're just walking on it, but it definitely is ice. Um, and we have a lot of safety measures in place because we're working on ice.
SPEAKER_01Yeah, you you still you're still working with with a wild animal in a very wild place. And so it is is still very important to be paying attention to those those safety measures. Okay, so tell us a little bit about the the project that you're part of, and then um the the questions that you were addressing for for your project.
SPEAKER_00The Weddle Seal Project has been going on for more than 50 years. It started in the 80s, and it's a capture mark recapture project in which basically every seal in our study area is individually marked and then followed throughout their lifetime. And so one of the big goals is to tag every single pup that's born in the study area every single year. And this provides us with ages if the pups come back and return and breed later on. Um, and it also allows us to know who which pup belongs to which mom and look at if things are passed from mom to pup. Um, and we can just keep track of the individuals and so we know um how often a female might breed and where she tends to breed and how many pups she's had in her lifetime. And so we get this really incredible detailed view of what's going on with the population and with individuals within the population. And because we tag every single pup in our study area every year, we know how many pups are born every year. And it's a very solid, easy number because that's our main goal is to tag every single pup. And what we've been seeing recently is the number of pups we're tagging every single year is changing. And we're not entirely sure why it's changing. So for the first couple decades of this project, that number was pretty steady. You could assume you're gonna go out for a couple of months and tag pups, and you are gonna tag a very specific number of pups, plus or minus like five pups. And the last couple of decades, we have not been seeing that. It's no longer plus or minus five. It's plus or minus a lot more pups. And we don't know why it's plus or minus that many more pups. And so what I'm trying to figure out is is why is it? Why is there more variation in the number of pups every year? Um, and and what could be contributing to that. And there's a lot of different directions that we could take with this. What I'm interested in is sort of what's going on in the environment that may be causing the variation we're seeing in these pup numbers. And so thinking about specific components of the environment that are important to seals, and then seeing if there are is variation in those um environmental variables, and if that is then affecting how many pups are born every year.
SPEAKER_01So just to just to make sure I'm understanding that for a really long time, there was a similar number of pups that were born in this study area every year, and now you've been seeing these shifts. And so you're saying maybe there's some other other factors that have had a similar pattern that were reasonably consistent for a while and then started to to change or started to vary, vary more that could help explain what's going on with the pups. And so, what are some of those environmental factors that you're you're considering that that might lend us a glimpse into what's going on in the lives of these seals?
SPEAKER_00One of the most important things for these seals is sea ice. And so they're what's called an ice obligate species, um, which means that they require ice to breed and they require ice to sort of live on while they're um at sea hunting for fish. Um, and so we're seeing, well, I think that maybe sea ice has something to do, um, and sea ice varies every year. So there's a lot of different ways you can measure sea ice. One of them is sea ice extent, which is how many miles the sea ice or that um, yeah, the sea ice goes out from the land edge until you get to open water. But another thing you can look at is sea ice concentration, which is within a specific area of the ocean, what percentage is open water versus what percentage of is sea ice. And those have those mean different things. So how far the sea ice goes is really important for seals when they're breeding, because that gives them a place to have their pups without predators coming and hunting their pups. But how much ice is what percentage of ice is in a specific area of the ocean is really important in figuring out what the light might look like for um for phytoplankton and for krill and for the whole productivity of that um area, which then translates into fish that the seals can eat and and get fat in order to produce more pups. Um and so there's yeah, there's so many different I I don't entirely know which exactly what exactly I'm gonna be looking at with sea ice, but it's a it's a pretty important factor for these seals. And that's part of the puzzle for me is trying to figure out what part of sea ice is important and when that part comes into play for this this question.
SPEAKER_01And so the the females, the moms of these um or the the females, whether or not they they do or don't have pups, they're spending a bunch of the year underwater feeding on on fish. And and then it's just this little bit of time in which they they haul out onto the sea ice and and and do or don't have have pups, or or they they would show up to have their pups and otherwise maybe aren't coming because they're not having having pups. And so you're trying to get with some of this. Sounds like you're trying to get a glimpse of what's going on in the rest of the year and not just what you see when they're when they're coming to the sea ice and and then having those pups.
SPEAKER_00Exactly. Yeah, we know when they come to shore and have their pups. We see that and we know what's going on, but we don't know what's going on for the other nine months out of the year. Um and we also know that it takes a ton of energy, a ton of fat reserves for these individuals to, you know, to give birth and to raise a pup. And so they have to be able to gain that back during the off season, off season. Um, I don't know if seals take an off-season, but it's my off-season, right? So the seals have to be able to regain that body mass in order to breed again the following year.
SPEAKER_01And and so are there factors that you're exploring that would help? Um, you mentioned you mentioned the um something about the food resources in one of those ice variables, but are there other things you're you're trying to look at to understand whether the females would be able to get enough food resources to then be able to reproduce?
SPEAKER_00That's the hardest question of this project, I think, for me, because there's not a lot of data available on the fish population. We actually know very little about the fish life cycle. Um, so we don't even know what's important to the fish. We don't know where the fish are, we don't know what they eat. Um, there's just a lot of unknowns in that system. And so I'm trying to figure out, yeah, I don't really know. Um I think sea surface temperature can also be an important factor because it can contribute to how much phytoplankton is it grows. Um and those two are big in terms of figuring out what's going on in the environment. Um, you can also look at um currents within the ocean to figure out how nutrients are moving and maybe think about if there's more nutrients in the ocean, then maybe there are more fish for the seals to eat.
SPEAKER_01So the phytoplankton lead to more fish, which then provides food for both one or both of those are providing food for for the seals with the the sea ice or the sea surface temperature.
SPEAKER_00That's my hope. When we'll see if that comes out, yeah. We'll see if that's actually if that's how it works out for me.
SPEAKER_01And that sea ice is forming, um forming at certain times of the year. It's not there all year round. And so does that is that a thing that you're considering of of when the sea ice, when the sea ice is present and when it is is forming?
SPEAKER_00So the sea ice normally forms in August, and that's um when it gets really thick and it latches to land and the seals go breed. And that's been relatively consistent. And we have past data that shows that even when that's those days have changed, when it forms later, that hasn't impacted breeding as much. Um, but I am interested in in sort of also in sea ice concentration too. And so depending on when the sea ice forms, you're probably going to get more sea ice in in the ocean afterwards. And so they're all sort of related and trying to figure out what each of them means and how they contribute to wetal seals, you know, getting body reserves is what I have to figure out.
SPEAKER_01Yeah. So so again, back to your question of why is there variation in the number of pups that are being born in your your study area. There, there's a lot of a lot of avenues to to explore and maybe more than one operating at the same time.
SPEAKER_00Exactly. And yeah, maybe it's a combination of how things are interacting. Um, or maybe in one year a specific thing matters a lot more than in the next year.
SPEAKER_01Wow. Um, okay, with all these pieces, um, what would you say about why your research is important? And that could be your piece of the puzzle or this larger, larger project that you're involved with that's been going on for decades.
SPEAKER_00I think the the project and my piece are important for a lot of different reasons. One is that the environment, there's a lot of climate variation and environmental variation happening. And um, it's thought that the poles, so environments at the high latitudes like the Arctic and the Antarctic are getting affected a lot faster. So they're changing a lot faster than the rest of the world. And um, because the species is so reliant on environmental variables and on this ice, they can kind of be a good indicator species about what's going on with the environment. Um, and at a time when the environment is changing faster than we've seen in the past, understanding what's going on with the environment and how that's impacting wildlife is really important in order to figure out how to conserve them and what might be happening to them in the future. The other interesting thing about this species is they exist in Antarctica, which isn't owned by country. So, unlike in the US, when you decide to conserve a species and you can pass a law, the Antarctic is governed by the Antarctic Treaty, which is I think 54 countries signed it in order to keep that area just for research. But that the treaty is expiring in about 15 years. And so providing more data about what's going on with the wildlife in order to help um 54 countries decide how they want to manage this huge continent all by themselves. Um, and so I think the more data that's that are available going into that treaty and going into working with other countries is is important in in conserving that space and making sure it stays for research.
SPEAKER_01It is a pretty remarkable um place and and and thing that you're just describing is is yeah, getting a whole bunch of different countries that have maybe different priorities, but coming together to to some degree of agreement and the fact that of exactly how much research is happening in this place is pretty remarkable of not just wildlife-related research, but on all kinds of other factors, and and that there's been this commitment to to learning, to to scientific understanding and pursuit is pretty, pretty impressive.
SPEAKER_00Yeah, I know people also study the politics of Antarctica, of like what could it look like if all the countries work together harmoniously and Antarctica's the case study there.
SPEAKER_01Sure. And and I liked what you said earlier too about the the poles, both the Arctic in the north and the Antarctic in the south is yeah, it's like sending it giving us these really important pieces of information about where change is happening quite quite quickly. And we're seeing in in other systems this these environmental changes and the changes in the timing you talked about, the phonology of when things happen. And so yeah, I can completely see why why generating these these uh this understanding is is really important for much more than these really cool seals. So if you had uh a blank check that you could use for your research um or for something else related to your research, can you imagine something that you would that you would do for either and I guess I should say for you for conservation or um in general or or for your study species? Can you imagine something you would do if if money was no object?
SPEAKER_00That's such a fun question. And impossible. Well the first thing that comes to my mind is putting on GPS trackers on all of our seals. So we don't know where the seals go in the winter, which makes it very difficult to understand what environmental variables are important to them because we don't actually know who's, you know, how many of them go to this part of the ocean versus that part. And some of them stay in the area and overwinter. And so I think it would be really awesome if we could put on GPS units and figure out what they're doing in the nine months of the out of the year where we're not there and we have no idea where they are or what they're doing. And knowing that is going to help us ask better questions, probably.
SPEAKER_01Yeah, it's it's it's interesting to think that your species um is on the sea ice, ready for you to study them for this little window of time and then and then gone, right? And and then the rest of the year it gets it gets much more, much more challenging. And so helping you get a get a look into what's going on um in these time periods that you think are probably really important for contributing to whether they they do or don't have pops in a given year.
SPEAKER_00Yeah, and and the research about where they go has shown that there's a lot of different areas. So they'll have you know a sample size of 10 or 12 and they'll go to 10 different areas, which is really cool. But then it's hard to figure out if there's a specific area that then, you know, you're more likely to breed if you went and you ate in that area over winter, because with a sample size of 10, you don't know that. But with a sample size of 2000, it's a lot of money, but you know, maybe we could figure some other things out.
SPEAKER_01Man, I wish I had a blank check to hand you right now because it would be so cool to see what you what you could learn. Um, we wrap up these podcast interviews with um with the the wild card question. We we sometimes call it about your your favorite animal or your favorite plant. And I'm curious what the answer is for you.
SPEAKER_00I feel obligated to say the wettle seal because that's my study species. And I do love them, they're very cute. Um, but my my original love is the jaguar. Um, and I was really fortunate to be able to work around them and do some conservation work in Brazil with jaguars and um being up close and personal with such a large and formidable cat that has such an important conservation value. They're really a flagship species for conserving, or like a really important iconic species for conserving most of the South America wild, you know, jungle and environment. Um, just to be able to be around such a powerful and important cat was really cool. Um they're always going to have a soft spot for me.
SPEAKER_01Sure. And you know, and it's so hard to just pick one. I mean, I also you also mentioned working with penguins. And so there's so many amazing species that one one could pick. It's it is almost an unfair question. So uh I I too would would struggle with just having having one, but that sounds like a a really, a really good choice. Marker, thanks so much for taking the time to to talk with me today, telling us about your your interesting global path to get to this place and about your your equally fascinating research on on weddse seals in Antarctica. And and and I really wish you the best of luck in in figuring out putting these pieces of the puzzle together and figuring out what's going on with these seals and and giving us a glimpse of the mystery.
SPEAKER_00Thank you. Thanks so much for having me.
SPEAKER_01And thanks to all of you for listening to today's voices of conservation science. If you're enjoying the podcast, please leave us a review or share it with a friend. You can find us on Apple Podcasts, on Spotify, Amazon Music, and on Stitcher. And we'd love to hear from you as well. So send us your thoughts about the podcast or give us any questions that you might have for our guests. You can email us at today'svoices at montana.edu.