60– Seize the carp! How zooplankton can reduce algal blooms in Utah lake, with undergraduate researcher Cristina Chirvasa

February 07, 2022 Utah State University Office of Research
60– Seize the carp! How zooplankton can reduce algal blooms in Utah lake, with undergraduate researcher Cristina Chirvasa
Show Notes Transcript

This episode is about Utah lake. A body of water that some people find a bit gross. Learn how Utah Lake earned its reputation. What's being done to help the lake's ecological processes recover. And how an undergraduate research project is supporting those efforts.

[00:00:00] Wyatt Archer: A lot of people think Utah lake is kinda gross, but you kind of think it's interesting why, 

[00:00:08] Cristina Chirvasa: I mean, honestly the fact that it is gross makes it kind of interesting to me, you know, cause it's a little puzzle, you know, trying to figure out how to make it back to not being gross. 

[00:00:20] Wyatt Archer: This episode is about Utah lake.

[00:00:21] A body of water that many people think is kind of gross today. You'll hear how Utah lake earned its murky reputation and what's being done to help the lakes, ecological processes recover. You'll also hear how Christina Chirvasa undergraduate research project supports those efforts moving forward and how USU undergraduate research program supports Utah's future land stewardship research.

[00:00:46] Like this one. 

[00:00:48] Cristina Chirvasa: My name is Cristina Chirvasa and I'm a sophomore undergraduate researcher here at USU. Um, I work for the lake ecology lab with Dr. Timothy Walworth 

[00:01:00] Wyatt Archer: in this project of Christina's, she's looking at the interactions between carp, zooplankton and phytoplankton and Utah lake.

[00:01:09] In my interview with her, she explains to me how carp removal could correlate with a reduction in algal blooms. You'll hear that. And you'll hear me explained how carp ended up in Utah lake in the first place. My name is Wyatt Archer, and you could be pulling the bones out of the invasive fish on your dinner.

[00:01:27] But you are listening to this instead, a podcast from the office of research at Utah state university, how do you feel about carpet and working with them? 

[00:01:39] Cristina Chirvasa: I think I have a healthy respect for carp, just cause they're so good at what they do, but they are an invasive species and they are causing a lot of problems on Utah lake.

[00:01:47] So I definitely think we should keep removing them. How do 

[00:01:51] Wyatt Archer: people feel about them? What do they look like? What do they do? Give me the lowdown 

[00:01:55] Cristina Chirvasa: I think a lot of people hate carp, um, which I understand why, you know, they cause a lot of ecosystem problems. They uproot vegetation, they compete with other fish by either directly eating the food or, um, I guess for habitat too, um, anglers are also not super happy with carp just cause they are, they're really good at colonizing the ecosystems that they're in.

[00:02:20] So they take up the space of other fish and you tell like, Um, there's like walleye, white bass, um, catfish, all those fish that people like to fish for. Um, so anglers want more of those and we also have the endemic June sucker, so it can only, it's only naturally found in Utah lake. Um, so that's really the primary reason that Carper mobile started.

[00:02:46] Um, It's just to help the June sucker, which has now been down listed from endangered or threatened, which is super nice. Um, the removal project is showing promise. Um, we've gotten them down, I think like 70% since 2013, they've gone a little bit up recently, but I think if we continue the efforts, it'll be fine.

[00:03:10] Wyatt Archer: We have water that we now call the Utah lake was important to the people who were native to this area. It was an important meeting place and resource for Paiute, Ute and Shoshone peoples the common European carp was introduced into Utah lake in 1880. At the time, introducing carp into an ecosystem was a pretty common practice of European settlers, which is why the common European carp can be found wreaking havoc on ecosystems pretty much around the world.

[00:03:38] The carp in Utah lake served as an important food source for awhile. It was especially important during the first world war, but as Americans recovered from the great depression taste buds changed, and people started preferring chicken and beef and other land creatures over fish. And when Americans do eat fish, they prefer fish that they don't have to pull the bones out of as they eat it.

[00:03:58] So even. Has a mild flavor. There's still not much demand for it. There's also not much demand for Utah lake carp because studies have found elevated levels of polychlorinated-biphenyls, or PCBs, a pollutant known to cause birth defects, cancer and skin condition. So there's not much commercial demand for the carp in Utah lake, but the carpet is still commercially fished because we don't want them in Utah lake anymore.

[00:04:23] So Utah's department of natural resources, contracts with a commercial fishing company. The department pays The Loy fishing company about 20 cents a pound for carpet pulled out of Utah lake. And most of that carp just gets compost. And this fishing is happening year round because there's a goal to pull 5 million pounds of carp out of the lake a year to keep up with carp reproduction.

[00:04:43] As of November 20th, 2017 million pounds of carp have been removed from Utah. Okay. So that's why it's primer on the carpet of Utah lake. I'll put links to the resources I used in the episode description. But if this episode is kind of about why Utah lake is gross, we can't just talk about carpet. We need to talk about algal blooms as well.

[00:05:04] And here's Christina explaining the conditions that lead to algal blooms in Utah Lake

[00:05:12] Cristina Chirvasa: so Utah lake is a semi-urban lake, so it's got a lot of human influences around that. So the reason that algal blooms are happening is primarily just due to agricultural runoff and also human waste.

[00:05:25] Wyatt Archer: There's a lot of people doing a lot of things with Utah Lake. Like tell me about your. The specific piece of Utah lakes, um, ecosystem that you're looking at. 

[00:05:34] Cristina Chirvasa: Yeah. So I'm primarily looking at zooplankton right now. Um, I just finished a project analyzing how's Oak length and size was changing as a result of, um, increased carp biomass.

[00:05:45] Um, and now I'm going to be expanding it to see whether those Oak LinkedIn sizes, the size changes are impacting the algal blooms. What is zooplankton. Okay. So plankton are these like tiny little animals that live in all while their bodies. Um, so basically like if you think of phytoplankton, they're these like tiny little, um, algae and things like that, they're microscopic and they post synthesize.

[00:06:11] So zooplankton they're kind of, I guess like the, is almost to that, um, where they're like actually animals and not plants. So they're. 

[00:06:19] Zooplankton feed on the phytoplankton. Yes. Okay. So we have algal blooms, which is a lot of vital plankton, and that leads to better conditions for Zoho plankton, perhaps, or it leads to more food, but maybe not better conditions for zooplankton.

[00:06:34] And there is a cap at which there's too much phytoplankton and zooplankton can't really, um, you know, combat it.

[00:06:42] Wyatt Archer: But then what happens to thisZooplannkton? 

[00:06:44] Cristina Chirvasa: Yeah. So zooplankton are actually. Important step in the well chain in the food web, I guess. Um, cause they transfer that energy from the phytoplankton to fish and from fish to birds and you know, the whole ecosystem.

[00:06:58] So pretty much the whole ecosystem really does rely on them to get that primary energy. 

[00:07:04] Wyatt Archer: So Utah lake has algal blooms though. Plankton feed on the organisms that cause algal blooms. But if there's a lot of carp out there eating zoo plankton, there's not as much as oh, plankton out there eating the organisms that make up algal blooms.

[00:07:17] And that's why it's so cool that Christina gets to studies. Oh, plankton and the lab. And this is how Christina gets her hands on the zoo plankton before she puts it under the microscope. Tell me about the work you did in Utah lake to go and get those samples. 

[00:07:33] Cristina Chirvasa: So we have our lab technicians, including me do field work for the summer months.

[00:07:37] So it's usually may through October. Um, but we do a lot of things and zooplankton sampling is one of those. So we leave from here and drive down to Provo. Um, and we get our boat, which is just like a small fishing boat with a motor on it. And then we launch it and head out to our nine sites around Utah lake.

[00:07:58] We have the. Zooplankton that, that we use, it's just like a really small size mesh net. And we dip into the water and grab it back out. And then all those Oak LinkedIn collect along than that. And like in the bottom, um, is this little container that we want them to be in. So we'll get ethanol that we have on the boat and just score that off real quick and get all those openings LinkedIn into that container and then transfer them to a cup so we can transport it back up to Logan.

[00:08:27] Wyatt Archer: So when you're dipping, the net is like a scooping motion. 

[00:08:30] Cristina Chirvasa: It's like straight down. We want it to be vertical just so we can, um, get this ope lengthy. And if it's a little sideways, you don't get like a proper read. 

[00:08:41] Yeah. You collect your zoo plankton, you come back up here to Logan. How do you analyze that?

[00:08:47] Wyatt Archer: What are you studying in that sample? What are you looking for?

[00:08:49] Cristina Chirvasa: Yeah, so we, we sub sample it cause, um, there would just be way too many, so plankton to do the whole sample. And so I do three sub samples. Count all those openings. And though we see, we identify them to a specific taxa. Um, usually not to species it's usually genus.

[00:09:06] Um, and we measure 10 individuals of each taxa. Um, 

[00:09:11] Wyatt Archer: and then how does that information improve our understanding of what's happening in Utah lake? 

[00:09:17] Cristina Chirvasa: Well, it allows us to see what those opening thing community is. What, um, tacks of soap LinkedIn are there. Um, Daphnia specifically is a really good one for like keeping algal blooms on there.

[00:09:31] Let's see in control. Cause it's a pretty heavy Grazer. It's really good at grazing. Um, well at least that's our theory. Haven't confirmed that yet. Um, also the size is important in that. As my project showed bigger zooplankton, um, are hopefully better able to graze, um, algae blooms. Um, we don't know if that's true for you to lake just cause it's so big that it might be a little too hard for them to really have that effect.

[00:10:01] Um, there may be too many other outside sources like too, too many nutrients coming in and empowering those algal blooms. So they can't really combat it in smaller. There's been research that indicates that bigger is ope LinkedIn. They're better able to graze algal blooms. And then we also are interested in biomass, which is why we count them to see exactly how many soap LinkedIn are there.

[00:10:22] Wyatt Archer: How can your findings help? Utah lake being managed. 

[00:10:27] Cristina Chirvasa: Um, I think mostly it would just support like removal efforts. I, it does cost a lot of money and, you know, it takes a lot of manpower to remove these carp. There's a lot of them. Um, so you know, the more benefits that we see to this project, the more likely it is to continue.

[00:10:45] So w in my research, I found that reductions in carp biomass do tend to. Lead to increases in his own plankton size structure. So if we continue this carp removal, our zooplankton will likely get bigger. Um, and that will hopefully translate to less algal blooms, but I'm working on that part of the research right now.

[00:11:09] Wyatt Archer: So bigger zooplankton are better able to feed on algal, blooms and carp like to eat bigger old plankton. Cause they're easier to find. So reducing carp should lead to an increase in larger Zoe plankton, which may lead to a decrease in algal blooms. Christina's research helps to show that this research project benefits our understanding of what's happening in Utah lake, but it also benefits Christina's.

[00:11:35] Here's Christina talking about how undergraduate research benefits. 

[00:11:39] Cristina Chirvasa: I have interest in a wide range of things, but most likely I will end up in some research career. I am enjoying the process. Um, I'd like to study. You know, climate change impacts on species and just help mitigate the species loss that we've got.

[00:11:56] And just like the ecosystem negative side effects that we've sort of caused through climate change and habitat removal and things like that.

[00:12:07] Wyatt Archer: How will being an undergraduate researcher benefit your career or how is it benefiting your career? 

[00:12:13] Cristina Chirvasa: Well in my field of like natural resources, most jobs require at least a master's degree.

[00:12:19] So you have to do some sort of research. So I think getting this, I guess, headstart on that is going to be super beneficial. And I'm also building a lot of like good skills, you know, just field work and coding and just designing a project is going to be super helpful for me in the future. 

[00:12:37] What's been the most fun part of this.

[00:12:39] The most fun part I think is just the field work. I really enjoyed being out there, you know, working with fish, gathering data. It's been great. 

[00:12:47] Wyatt Archer: Okay. So that is how one undergraduate research project is helping to further our understanding of a critical ecosystem in Utah. While also being an important experience in the development of a researcher's future.

[00:13:00] Thank you for listening to this podcast, please subscribe and scroll through our 59 other episodes where hopefully some other topics will peak your interest. If you want to learn more about algal blooms, try episode seven or episode 57, if you want to get involved with research, listen to episode 58, where researchers come from, how six people turned an interest into a profession.

[00:13:23] Please take a minute to follow instead on Instagram at instead podcast. Thank you for listening to this episode, it was edited and produced by me. Why at Archer is part of my work in the office of research at Utah state university.