Dr. Jesse Reimink: [00:00:00] Mr. Bull Heis. Hi.

Chris Bolhuis: How you doing Dr. Reimink?

Dr. Jesse Reimink: I'm great. I'm great, man. We're continuing on here on Yellowstone and we're just moving through geological features at a ridiculous clip and we're on Yellowstone Lake now.

Chris Bolhuis: I know.

Dr. Jesse Reimink: so fun. I mean, we're like really just blasting through these things and time we want to sit down and record a chapter here about something, we [00:00:30] end up. Going way too long or wanting to talk way too long, and so we want to keep these relatively short and to the point, and so we're working on that. Right?

Chris Bolhuis: We are, it's a work in progress, but Now we're gonna talk about the Geology of Yellowstone Lake and the immediate vicinity. the immediate surrounding, important things going on. And we're also gonna discuss the major ecological concern in Yellowstone, the Lake trout issue. So let's turn everybody to image number one. That is a [00:01:00] stunning image of Yellowstone Lake. This is hard to capture, right? For, unless you're looking at this from a 30,000 foot view, which we're not, it's hard to capture because it's an immense lake. and you know, I get warm and fuzzy when I think about Yellowstone Lake inside. I really do,

Dr. Jesse Reimink: you get warm and fuzzy everywhere you go. In Yellowstone, you're just like a, a hive of warm, fuzzy feelings whenever you're in Yellowstone, I think.

Chris Bolhuis: I am, I am. But this is a place to me that is unrivaled beauty.[00:01:30] I have seen this lake from so many vantage points. I've seen it from along the shoreline. I've swam in it. For only short periods of time, cuz it's an immensely cold lake. It's notorious, it's shocking sometimes.

I've viewed it from high above in places like Avalanche Peak, which have recommended many times already. And I will again in the next chapter. Lake Butte Overlook, which is one of my favorite places in the park actually. Mount Washburn [00:02:00] Elephant Back Mountain.

Dr. Jesse Reimink: and I think Chris, the reason you can see Yellowstone Lake from all these vistas that you've just described really beautifully is cuz it's a massive feature. And you and I, we come from the land of massive lakes in Michigan. You know, we have the Great Lakes and so we're used to very large lakes, but Yellowstone is an image number one really kind of, Shows this. This is a huge feature. It's a huge geological feature. It's a huge hydrological feature. It's a huge ecological feature as well as we'll discuss at the end of this, and it's really [00:02:30] important and interesting. So just let me go through a couple of the facts that kind of, you know, summarize how big this thing is. There's over 140 miles of shoreline around Yellowstone Lake. It's over 400 feet deep in places, which is kind of surprising given that, you know, lake Michigan, which is a monster lake, doesn't really get that deep very frequently. this, this is actually quite a deep lake given the, the aerial size of it. It's the largest lake in North America that's over 7,000 feet above sea level. So, That's kind of [00:03:00] a, you know, an impressive metal that it gets there. And we'll talk about this a bit. So let's just introduce the kind of shape, because we're gonna talk about the shape a lot. It has this shape of a hand. You've described this before. It looks like a hand we can point to image number two that, kind of shows these three gnarled fingers that. Point to the south and southeast, and a little thumb that sticks out to the Southwest, which is aptly named West Thumb. So image number two just kind of shows what we're gonna be talking about as we talk through the [00:03:30] Geology of Yellowstone Lake in this episode.

Chris Bolhuis: alright, Jesse, and also I want to add a couple things to what you said. There are so many hydrothermal features that are visible on the North Shore, the West shore, and The lake is similar to the rest of Yellowstone, at least inside the Caldera. If we drained the water out of that lake, which would not be a good thing, okay, um, not a good thing at all. But if we drained all the water out of that, would see geysers, hot [00:04:00] springs, fumaroles, maybe mud pots. You'd see all the hydrothermal features that we've already discussed. It's very, very active.

Dr. Jesse Reimink: I think that's such a cool part of this, Chris, that the lake is really just covering up basically very similar Geology as you see outside of the lake, that there's hydrothermal stuff going on, and we'll talk about how that's really important. That's a really, really important and super relevant part Part of this geological story of Yellowstone Lake is that there are hydrothermal features, and we'll come back to that kind of middle of this [00:04:30] episode, and it's a really important one. I think we're gonna belabor that point quite a bit because it's, it's really quite important here.

Chris Bolhuis: so Jesse, before we move on to the specific Geology of the lake, I just wanna point again to image number two in your stack, and I wanna emphasize the three gnarled fingers or what are called arms in Yellowstone Lake.

there's the flat mountain arm, the south arm, and the southeast arm of Yellowstone Lake. And represent those kind of like distorted or gnarled fingers that extend out from the palm [00:05:00] of the hand of the main body of the lake.

Dr. Jesse Reimink: And Chris, I think, uh, we can move there that image number two, that gift that shows those arms. Let's move to image number three real quick, because image number three shows that there's two kind of different. Types of underlying Geology underneath of Yellowstone Lake, meaning, in other words, Yellowstone Lake straddles two different geological domains underneath of it. the northern kind of two-thirds of the lake. And this is shown in image number three in a gif here. The northern kind of two-thirds of that, or the Northwestern two-thirds are [00:05:30] inside the Caldera. And so the structures, the processes that are going on underneath of the lake or within the lake are really governed by. The same processes that are going on in the Caldera in Yellowstone National Park. The Southern one third of the lake is much more shaped by tectonics rivers and glaciers. It's not in the Caldera. And so there's really some key differences between those two that we're gonna talk through. Chris, that

Chris Bolhuis: That is correct. But I do want to point out that although the northern two-thirds of the lake that shown in that kind of purple color there[00:06:00] there's overlap. With what's going on there, because not only has that been governed by what's, inside the Caldera, so it's gonna have all the hydrothermal activity and it's, it's governed by volcanism beneath it.

Right. But it's also been affected by glaciers. During the last Ice age, glaciers affected the whole lake. Okay. And so it's just the three arms that are outside of that Caldera, those have been governed by processes that are not really volcanic in nature. So there is some overlap. I [00:06:30] guess that's the point I wanted to make.

Dr. Jesse Reimink: Totally. And I, you know, we, we kind of come back to this, like we talked about this with the Yellowstone River, that, you know, when there's a little rapid somewhere, it's because of the underlying Geology. So those arm features are there because of the underlying Geology. And, really, I mean, everything comes back to the Geology.

I just, we just have to accept that, you know

Chris Bolhuis: we have to embrace that. Everybody

Dr. Jesse Reimink: That's the word. That's the word. Exactly. Exactly.

Chris Bolhuis: All right, Jesse, let's transition then to talk about how do we know about the bottom of the lake? [00:07:00] Cuz this is a, it's a big, vast lake and it's deep as you said. This has been studied by these submersibles So what we know is that these post caldera lava flows that we've talked about, we talked about it in the last chapter with, the role that they had in the formation of the Grand Canyon of the Yellowstone River.

we see the same things in the bottom of Yellowstone Lake.

Dr. Jesse Reimink: so,

Chris, this is something that's kind of a dream of mine, frankly, like one of my colleagues, Got the chance to [00:07:30] go down into Alvin, you know, the little submersible that goes down and looks at mid ocean ridges and sees all these hard, he got to go in Alvin.

I mean, that's so cool. Like geologist dream type stuff. And the videos from these ROVs are really, really cool. I'm kind of a big guy, so I wouldn't really fit very well in these, I don't think. But it would be so fun to go down in one of these submersibles in Yellowstone and you know, drive around and look at All these features cuz there's amazing stuff down there, like amazing features at the base of this lake that [00:08:00] you don't see in very many lakes around the world at all.

This is like a totally unique situation.

Chris Bolhuis: from these videos we can see, and we've studied that the bottom of the lake is dominated by these lava flows that, We talked about how they affected the Grand Canyon of the Yellowstone River and, and helped play a very vital role in the formation of that whole canyon.

they also play a vital role in, the Geology of the bottom of Yellowstone Lake, and you get all this hydrothermal activity that's dominant on the [00:08:30] northern shoreline, the central part of the lake and the whole western shoreline there, particularly down by the West thumb area. So This theme that comes back again and again and again. But I do have to say, Jesse, that one of the funniest things that's running through my head right now is imagining you in a submersible steering it. I just, I, I can just see you with your knees up by your chin, you know, with a little steering wheel out in front of you. It's,

Dr. Jesse Reimink: the, it's a great visual. we one time had a, uh, I had a [00:09:00] helicopter pilot who was flying us around in the northwest territories looking at rocks, and he was a six foot eight Irish guy. And him flying this tiny little bell helicopter was hilarious. He was exactly as describing knees up around your ears, almost like a, you know, a comic book situation.

But That's what I would look like in a, in a

rover for sure. So, Chris, let's.

It's a great one. This is a really interesting feature given the documentation we have at the, the base of the lake of over 700 hydrothermal vent craters, and these are between one and like [00:09:30] 200 meters in diameter.

Quite large, potentially, and also quite small. But the stat That really impresses me is that estimates are that 10% of all the hydrothermal activity. In Yellowstone happens underneath the lake, which is really kind of impressive when you drive around and look at all the hydrothermal features and all that activity, I mean, it's everywhere in the park.

You're only seeing, 90% of it. If you looked at every one of 'em, there's 10% under the lake. That's really cool. It's a really cool thing, I think.

Chris Bolhuis: Jesse, I want to touch on that too, that not only do we have [00:10:00] those craters that go from one to 200 meters, I think you said, but We have several larger hydrothermal explosion craters up to 1.2 kilometers in diameter. So I wanna point you all to image number four in your stack here.

This is a great gide image showing Yellowstone Lake. In the inset, it's pointing also to two very large hydrothermal explosions, Mary Bay and Elliot's Crater, [00:10:30] which is well inside of the lake. these are huge features

by the way. Bay is the largest known hydrothermal explosion to have ever occurred in the world.

So this is massive.

Dr. Jesse Reimink: Well, I, I think Chris, why don't you wrap up and then I think I want to, we need to spend a little bit of time describing how this works. So just, sorry. Finish your thought and then I, I just wanna spend some time, I'm excited to talk about these things. There's such a cool story.

Chris Bolhuis: Well, there's this potential of, These enormous tsunami kind of waves or [00:11:00] tsunami like waves with these, hydrothermal explosions, if everybody looks at image number four, again, I want to draw your attention to Elliot's Crater. This is well within the lake. It's south and west of Mary Bay a little bit, and this is a huge explosion crater here.

Imagine the potential of the wave that could be created by an explosion beneath this much water. Jesse, you and I recently had a [00:11:30] discussion with the scientist in charge of the Yellowstone Volcano Observatory, Dr.

Mike Poland he talked about this. He talked about the potential of these hydrothermal explosions and these enormous waves that can be created, a thrown landward from this kind of thing.

Dr. Jesse Reimink: it's really, really a cool story. So let, just summarize this, and we talked about hydrothermal, explosions or how hydrothermal stuff operates in the park. we had the chapter where we talked about geysers and, hot springs and all that. I think we need to, to kind of [00:12:00] just hit this again really quickly cuz I, it's not necessarily the most intuitive thing. Remember that schematic and the one you use, Chris, when you are in Yellowstone National Park, you set up on the boardwalk, you got this hot plate, you got this big vat of water with a little siphon tube that goes up. And that water gets really, really hot down deep. It gets hotter than boiling point, but it's held as water because there's all that pressure above it, pushing it down, and the pressure keeps it from going to steam, flashing to steam.[00:12:30] And one thing I think That's important here is those things are like really typically hanging right. around that edge. They're kind of modulated to that critical point where they're almost about to erupt, but they don't erupt. They're always kind of hanging out red on the edge. So any little change in the pressure above it, like for instance, A deep lake's worth of water hanging out above it. All that pressure is keeping that steam in liquid form. It wants to be steam, but it's too pressurized, and so any little change in the pressure, any little release of [00:13:00] pressure can make that stuff flash to steam and just explode, basically. Right. Chris, is that, I mean, is that, that's kind of what we're describing here is this big flash to steam and a massive explosion actually. I mean, they're

Chris Bolhuis: that's right. And you know, we, talked about a possible mechanism for this in the last chapter with the Yellowstone of the Grand Canyon. We talked about these ice dams that broke at the end of the last ice age. And so you had this rapid release of water down the Yellowstone, and that rapid release of water [00:13:30] is. Linked to the formation of these hydrothermal explosions? Well, Yellowstone is still very, very active and, tectonics for instance, could change how much water is in Yellowstone Lake. We talk about faults and fractures on the northern end of Yellowstone Lake, like by fishing bridge. There, there's an active groin there, and what a groin is, it's this area where faulting takes place and there's a [00:14:00] sudden drop in a block of rock. Well, if that happened, that kind of faulting with a sudden drop could cause a rapid release of water down the Yellowstone River downstream and change the pressure. Of all of the water on top of these hydrothermal features in the bottom of the lake.

Not a good, scenario for

Dr. Jesse Reimink: No. That's right. Kristen, when we were talking to, to Dr. Mike Poland about this, he said, A lot of people worry, you know, think about this supervolcano eruption. they say, oh, it's overdue. And [00:14:30] we've talked about how that's not actually the case, but, Actually the, more legitimate concern is something like this happening, and you know, it doesn't need to be water draining out of the lake necessarily. You can also have faults that dump a bunch of, mass into the lake and cause a big wave that moves across and pressure undulation can. Potentially cause some of these things to erupt. Cuz again, these things are kind of hanging right. on the edge of stability. And so, you know, there's a lot of things to, potentially think about here, but it's really just a super, super, [00:15:00] super cool story and realization when you're looking out over Yellowstone Lake, if you're standing on the shore looking out across to, to imagine all that hydrothermal activity going on underneath of there.

Chris Bolhuis: And I'm gonna interrupt you a second, Jesse, because that is such a good point. When you look from above down on Yellowstone Lake, it looks tranquil, it looks so peaceful, so beautiful. But there's a lot going on underneath the surface, and I think that that realization is, it's awesome. It's [00:15:30] amazing to just sit there and think about those kinds of things. When you look at this tranquil lake.

Dr. Jesse Reimink: There's a couple other features that we've noticed which are really worth pointing out here. Again, by these sort of underwater surveys, we get these really long hydrothermal spires, which are really made of silica, and this is this hydrothermal water that's moving around through the rye light, reacting with it, soaking up the silica, and then when it erupts or when it kind of pours out, this hot water pours out into the really cold lake that silica drops out and forms basically quarts. I mean, it's [00:16:00] essentially quarts, but forms. This silica spire that's sort of growing up and they can be up to eight meters long. I mean, these are massive, massive features. We also see glacial kettles, especially in the southeast arm, which are a type of lake or depression that forms in glaciated terrain. So again, more evidence that glaciers really influence this region and, really influenced the lake region especially.

Chris Bolhuis: Can I explain the idea of these kettles a little bit a second. if you imagine if you take a frying pan, And pack [00:16:30] it with, mud and just compress it and push more in and compress it and push as much mud into a frying pen as you can. And then take some ice cubes and shove them into the mud. Okay, this is kind of how kettles form, right? we're talking about glaciers that are moving and there's a tremendous amount of sediment beneath the glaciers and so on, and chunks of ice get broken and buried by this sediment, and then eventually the ice melts just like the frying pan. You have these ice cubes that you shove down in 'em. When the ice cubes melt, you're gonna have [00:17:00] depressions that are left behind these pits from where the ice was, you know, we have these all over the place in Michigan. We have, over 10,000 lakes in the state of Michigan. And many of them are, kettle lakes. In other words, chunks of ice that got broken, buried, subsequently melted and filled with water. And that's what we see in the bottom of these arms. we see these kettles in there, these depressions that were formed in that way.

Dr. Jesse Reimink: Chris, that's a better [00:17:30] analogy than the, the baked potato you used last time. I think it made more intuitive sense to me. So nicely done. But I'm a little worried about you baked potatoes and frying. Are you a little hungry? Do you, do you need to go eat something real quick or

are, you know?

Chris Bolhuis: No, I'm good.

Dr. Jesse Reimink: You're good.

Okay.

All right. We can keep moving.

Chris Bolhuis: good. to go.

Dr. Jesse Reimink: let's move into the, the sort of overview of the geological stages here of Yellowstone Lake and how this thing developed. So, We're going to really focus a little bit on the arms, but more broadly, focus on [00:18:00] Yellowstone Lake. So it really started out by this large depression, as we talked about, two-thirds of the lake is within the Caldera.

And so this really started out as a large depression that was formed, you know, by the explosion and collapse of the Caldera and then filled in with water. So that, That's like starting point. Let's start from there, Chris. We got a calera water's filling in on this part. What happens next?

Chris Bolhuis: just like the rest of Yellowstone, what happened after this calera and subsequent collapse is these more recent lava flows and [00:18:30] these recent lava flows. they covered parts of the bottom of Yellowstone Lake and actually in the north, in the central, in the west thumb part of the basins there flows created three very prominent islands that you can see from these high vantage points, Yellowstone Lake. And I wanna point you all to image number five. These islands are Stevenson in the north. Frank Island in the South and Dot Island in the middle there, and that's because it's just this little tiny dot there. But these [00:19:00] are the three prominent islands. These three islands are just lava flows that kind of peak above the lake level.

Dr. Jesse Reimink: uh, that leads really nicely into, the third stage of the development here, which is a, and you'll notice this looking on the map. I mean, west Thumb, it's aptly named the West Thumb, cuz again, it looks like this hand and we can look at image.

Chris Bolhuis: a thumb that got slammed in a car door. You know,

Dr. Jesse Reimink: pretty beat up and battered. I mean, this is a, it's, it's a, it's a. big. old thumb hanging out there. Um, we can [00:19:30] look at image number five that kind of shows this again, but Chris, you know, this formed by. another volcanic eruption. So Westham formed by about an, It's an eight kilometer Caldera within the Caldera. So this is 174,000 years ago, roughly the size of Crater Lake, which is also called Mount Mazama in Oregon. There, So this is a big. calera. So you know, disabuse yourself with a notion that this is small. This is huge actually. It's just sitting inside of the most massive one, which is Yellowstone itself, right. So [00:20:00] this is a big big caldera inside of a super massive Caldera.

Chris Bolhuis: And then we're doing this in order. So really we're kind of on this fourth stage of what happened to Formula Yellowstone Lake. Well, the bottom line is then glaciers advanced and retreated. Many times through this area, they would advance south and then they'd kind of retreat back up to the north. so they were coming and going through the Yellowstone Lake region many, many times. And We alluded to the reason for this earlier on. The Yellowstone Plateau sits about a [00:20:30] kilometer higher than its surroundings, and that's due to this massive hotspot that's pushing from below like a piston, pushing the rocks above it, and it's causing Yellowstone to be elevated

Dr. Jesse Reimink: Yeah, it's Chris, let me interrupt real quick. because you know, it's like this kind of pushing up mechanism. It's also the heat too, right? When you get things hot, they expand and when you have like 30 kilometers of continental crust and it gets hot, that expands kind of a lot. You know, we can get a One kilometer topographic relief [00:21:00] because of that heat in just the expansion. But I want to just refresh this 30,000 foot view that we went through in, the earliest chapter, which is this, sitting in a hot air balloon watching these glaciers migrate around, and we really had this little mini ice cap on top of the Yellowstone Plateau. So let's not forget that. And let's not forget that 30,000 foot view. As we watched the glaciers come and go, we had. More ice here in Yellowstone. That's kind of a really important point that we need to keep talking about.

Chris Bolhuis: That's a good point. And [00:21:30] the final stage to Yellowstone Lake is really just continued development of hydrothermal activity. Just like what we've seen in many parts of the park that we've already discussed. We see it in the north. The central, the West thumb basins there. And again, not to belabor this point, but these hydrothermal explosions, things like Mary Bay, which again is the largest known hydrothermal explosion in the world. so go back to image four, but other features that you're [00:22:00] gonna see, Indian Pond. Storm point, which a highly recommended hike, it's flat, it's easy. Take the storm point trail out to the edge of Yellowstone Lake. It's gorgeous, and you'll see hydrothermal explosions there. Turbid Lake, just north of of Yellowstone Lake. These are, again, hydrothermal explosions that are really hard to miss. They look like hydrothermal explosions.

Dr. Jesse Reimink: I think, Chris, that's kind of brings us to the modern day and, and the view of Yellowstone [00:22:30] Lake. And, and I think this is a good transition to talk about one of the, the larger, if not the largest ecological problem, in Yellowstone National Park, which has to do with the lake trout and the cutthroat trout. So, uh, let's move into that and spend some time discussing this. So, There are native fish here and I'm a, I'm fairly large fly fisherman and, and cutthroat trout are really just such beautiful fish. And you can look at image number six here for a little gif of them swimming around. I could just watch this gif over and over and [00:23:00] over. So it's so calming and satisfying. but they're really spectacularly beautiful fish and they're native to this region and their lifecycle. This is an important point to talk about. Their lifecycle is kind of like salmon. every year they migrate back to their spawning grounds, which is usually a little river tributary. They swim upstream, lay their eggs on a gravel bed. After the eggs are fertilized, it gets covered up with gravel. They swim back to the lake, and so they go from the lake, from Yellowstone Lake upstream to spawn. So they do this [00:23:30] migration every time, and that that's a really, really important part of this ecological story and why they're important to the broader ecosystem here.

Chris Bolhuis: so Jesse, that's really important to bring up because as the Yellowstone Cutthroat Trout swim back and forth in these shallow streams, as you said, the key point is shallow. Right? That's important because it's a feeding ground for bears, for otters, for osprey and eagles. They just, there's a lot of [00:24:00] food and, and they're ready for them. so when the eggs hatch, especially too, the small fish swim back to the lake then the smaller birds can have their thing. So this is like very. Intertwined ecologically you know, dozens of species in the Yellowstone greater area rely upon the Yellowstone cutthroat trout, either directly or indirectly. And this food web gets complicated and it gets complicated fast. If the Yellowstone cutthroat trout are decimated, if their population [00:24:30] is eliminated or greatly reduced, many other animals and birds and other species would disappear from the area.

Dr. Jesse Reimink: if we, go back to, you know, when Chris Bull was a young lad in the 1890s. And, you know, early explorers were writing

Chris Bolhuis: Okay.

Dr. Jesse Reimink: and, you know, bison were ranging free across the prairies. No, seriously though these things were super, super abundant. Like early explorers wrote about this, right? Wrote

about how prevalent the cutthroat trout [00:25:00] were.

Chris Bolhuis: Well, I, I, I can speak to this in the seventies and eighties, but it was the 1970s and

eighties when I was a young, you know, just a young blonde, little kid. My brother and I went fishing in the river. I remember eating cutthroat trout on the grill.

I remember this actually when Jenny and I were just newly married. In the early 1990s, we were on our way out to Oregon and we [00:25:30] befriended two people that had a boat and they caught a bunch of fish and we were eating at night. We were eating fish that they caught that day. I mean, just doesn't happen anymore,

you

Dr. Jesse Reimink: And now fishing bridge is, is no longer, you know?

super aptly named because it's pretty rare to see cutthroat trout. You can occasionally catch them, you know, looking down in the river, you can occasionally see them, you know, catch them, meaning see them looking down in the river. But it's pretty rare.

And really what. Happened. Here is a combination of things as these go, but, but we're gonna talk about the lake [00:26:00] trout. Really is, part of the problem. There's overfishing, you.

know, a lot of that happened here in the east. I live in Pennsylvania right. now. You know, overfishing and pollution really decimated the native trout populations here, but we've become better at managing 'em and they're really rebounding, like the native trout populations are spectacular here in Pennsylvania.

And so, That recovered. But what hasn't recovered in Yellowstone is this competition from the Lake Trout

and, and that's

really kind of the key problem here.

Chris Bolhuis: Because the lake trout are not [00:26:30] native to Yellowstone Lake, and that's the problem. So in the summer of 1994, The first lake trout was caught in Yellowstone Lake, and I want to refer you to image number seven in your stack. This is an image of the lake trout, that we're gill netted on Yellowstone Lake.

They're not native and so the first one was caught in 1994. That's a big, big deal because lake trout are predators to the cutthroat trout, [00:27:00] and they don't go shallow to get eaten, so they decimate the Yellowstone cutthroat trout population.

Dr. Jesse Reimink: and this is really important. They, They don't just replace it, they're not a one-to-one ecological replacement for the cutthroat trout, cuz they don't go spawn in the shallow waters. And so therefore they're not eaten by the birds and the bears and the ospreys and, and all that.

they just live deep down in the lake. And Chris Lake Trout are all over in northern Canada. Some of the monster monster lakes that I do Geology on up in the Northwest Territories and in none of it, they're [00:27:30] just loaded with lake trouts. So these are really native to massive lakes and I kind of. I understand why.

You know, you would look at Yellowstone Lake and you would think there's lake trout in there, but there was not. They're not native, and so these were an introduced species. Somebody put lake trout in there at some point and they just exploded onto the scene and really decimated not only cutthroat, but the general ecological system.

Chris Bolhuis: Let me add some stats to this because I think they're striking. in 1994 at Clear Creek, which is a [00:28:00] tributary to Yellowstone Lake, there were 70,000 Yellowstone cutthroat trout that spawning. In 2007, there were 538.

Dr. Jesse Reimink: It's such a sobering stat.

Chris Bolhuis: like, I'm, I'm not going out on a limb when I say that this has been their biggest concern from a biological standpoint.

They're spending a massive amount of money to try to control this issue, like massive.

Dr. Jesse Reimink: and there's some success here. Like we're seeing signs, early, signs of [00:28:30] potential success. Yellowstone Park has worked with commercial boats to just basically go out and gill net and kill lake trout. Like we just have to cut the population down.

Probably never gonna get rid of 'em, but just manage the population. And so image number seven is, the results of a gill netting campaign and there's a bunch of lake trout. You can see there's a ton of lake trout and you're actually, if you're fishing and you catch a lake trout, you have to kill it. Like that is the, the rule is you have to kill this thing. You cannot put a live lake trout back in the lake cuz we just have to. Beat down the numbers of these things[00:29:00] to help let the cutthroat population recover, especially the Yellowstone Cutthroat trout. Re recover there.

Chris Bolhuis: and we are seeing the fruits of our labor with this, endeavor. We're starting to net a little less and less and less each year. But I do remember, Jesse, a few years ago, even when you came out a few years ago, I think in 2019, to visit us for a week or a week and a half, we didn't know which way this was gonna go.

We were at this kind of tipping point where we're gonna win this battle or we're gonna lose the [00:29:30] battle, and we really didn't know. But we feel like the coroner has been turned on this a little bit. We're netting less. I have actually seen in the last two years because when I take my students out there, we always do a service project and quite often I have.

26 high school students painting and cleaning, fishing bridge.

And so as I'm supervising, sometimes I just stand off and look at the river down below. And you know what Jesse? I have seen really [00:30:00] impressive cutthroat trout just sitting there right below the bridge. So that's such a good site to see.

Cuz you know what? I haven't seen him in 15 years.

Dr. Jesse Reimink: It sounds like a manager's job there, Chris. Just sit there and watch the trout while all the students are painting the bridge. Yeah, That's perfect. You got it made, man. Um, and the, I just wanna reiterate, these lake trout are invasive.

there's some DNA testings that says that they, came from Shoshone Lake, which is a very cool lake. Uh, but in 1890, the US Fish Commission. Planted lake trout there. [00:30:30] And so maybe they were introduced

then maybe.

Chris Bolhuis: interrupt you, Jesse. Just to be specific, they introduced Lake Trout in Shoshone and Lewis Lake, which is a lake in the very southern part of the park. and so it's possible that during that introduction process that maybe they were introduced into Yellowstone Lake too.

we don't really know.

The other possibility is that maybe anglers caught lake trout in Shoshone Lake or Louis Lake, put 'em in live wells and either on purpose or [00:31:00] inadvertently dumped them into Yellowstone Lake. We really don't know. you know they had a bounty, they offered a $10,000 reward for any information leading to, how they got there.

Dr. Jesse Reimink: it's a

serious problem, eh?

Chris Bolhuis: very, con Yeah,

very concerning issue.

Dr. Jesse Reimink: and I think it's a, it's another thing when you're sitting there looking at Yellowstone Lake, think about the geysers and all the underwater hydrothermal activity that's going on underneath the super calm surface, but also think about this ecological battle that is, we're really in the midst of watching this battle rage between, sort of [00:31:30] trying to recover from some of the damage that, sort of we have done to this ecological system at the moment.

So, Chris, I, that kind of wraps up this chapter, but let's go as we do to some frequently asked questions. Does that sound, uh, Okay. with you?

Chris Bolhuis: Yeah, I think we're about ready to wrap this up, so

let's go. We got some interesting things here.

Dr. Jesse Reimink: okay, Chris, so the first FAQ here is, how big is Yellowstone Lake and how deep specifically, that's a, a pretty commonly asked one.

Chris Bolhuis: Well, it's big and it's deep.

Um,

Dr. Jesse Reimink: Okay. Done. [00:32:00] Simple

Chris Bolhuis: it is,

Dr. Jesse Reimink: down to the next one.

Chris Bolhuis: um, deepest spot is 410 feet or 125 meters, and its average depth is 140 feet deep or 42.7 meters. here's an interesting thing that kind of relates to this. I think that. the Lake's water is completely replaced only about every eight to 10 years. I think. that's amazing. Yeah. That's a cool fact, right? All right, I have a frequently [00:32:30] asked question for you, Jesse. How cold is Yellowstone Lake?

Dr. Jesse Reimink: Oh man, we got cold. We can move on. very cold. Um, no, I, you know, Chris, I remember this when I came out, uh, on your summer science trip for week in 2019, I think it was. Yeah, I think it was Yellowstone Lake. Weren't we? Didn't we go on a hike and then we went swimming and we played chicken in, uh, in the shallow waters. And wasn't that Yellowstone Lake?

Chris Bolhuis: No, that was not Yellowstone Lake.

That was Shoshone Lake, which is a very cold lake [00:33:00] too. And I will say this, for the record, we dominated those little high school kids. I'll

Dr. Jesse Reimink: yeah. Well, I can't remember exa You you can see how terrible my memory is. I.

don't remember which lake we were in, but I think I was the base because

I'm like, you know, stronger than you.

Um, and.

Chris Bolhuis: 13.

Dr. Jesse Reimink: Yeah. And we did. we, we absolutely dominated

the students and the other instructors I might add in chicken, we just crushed them.

It was, uh, it was a bloodbath, so back to how cold it is. I [00:33:30] mean, all the water in Yellowstone National Park is pretty cold, but Yellowstone Lake is, is super cold. It rarely ever gets above 66 degrees Frey, That's around 19 degrees c it does get stratified, so you do get warm layers on top, like most lakes get stratified at some point. Um, It's really, really cold water though. and there's a note we have to make here that, like surviving in this super cold water, you just can't do it very long. You get hypothermic really, really quick. So you really gotta be careful around this lake. this is no joke, how cold the water is here. [00:34:00] and in winter. Yep.

Chris Bolhuis: have never seen it at 66 degrees.

Dr. Jesse Reimink: No, that's like super warm and balmy, right? Um, in winter, the ice, you know, does get covered with ice mostly, uh, very frequently at least. And, uh, you know, it can be a couple inches thick, but it could get to two feet. again, with many. Feet of snow on top of, of the

lake. So, It's super cool, super crazy.

So Yellowstone Lake.

is beautiful. I think we've given you a couple things to think about when you're looking out over this, what seems to be very peaceful,[00:34:30] lake and it is a very peaceful view, but don't forget that there's stuff happening within it

that's really important.

Chris Bolhuis: That's right. That's a

wrap.

Dr. Jesse Reimink: does wrap.

Super cool.

Great chapter Chris. love the

discussion.

Chris Bolhuis: You bet. Cheers.

Dr. Jesse Reimink: Peace.