Eric records outside amongst the deafening roar of millions of cicadas in Charlotte. Cicadas and other small animals that may wind up in the pool can affect water chemistry.
00:00 - Introduction
02:25 - Cicada broods every 13 or 17 years
05:44 - What do cicadas do?
07:03 - Cicadas and swimming pools
08:56 - What do cicadas introduce into swimming pool water?
10:44 - How to get cicadas out of the pool
11:29 - Other small dead animals in pools
13:02 - Closing
[00:00:00] Eric Knight: Are you hearing that? That's the sound of millions if not billions of cicadas in my backyard and neighborhood. It's got that low humming roar all day long for the past three or four days. That high pitched rattle of them in my trees. And I can literally look at my branches right now and see each branch moving.
[00:00:35] There are so many of these bugs, it's amazing! Welcome to the Rule Your Pool podcast. This is a different episode. This is episode 141 and I got to be honest, this was not in my plan to talk about. I have a pretty robust content schedule for the summer and some very cool guests, but it's hard to get them on the schedule because well, they're busy. But yet this happened about two or three days ago and it's deafening.
[00:01:05] It has been so hard to have any peace and quiet during the day because of these cicadas. And then I remembered in 2021, I wrote a blog about cicadas and swimming pools. In fact, you can find it on our website. Just search in any of the search bars, the word cicada. CICADA, and you'll find it. I wrote that in 2021 because I grew up in Northern Virginia where brood 10 or brood X of cicadas are on a 17 year cycle.
[00:01:34] And I remember 2004 when they came out and they were everywhere. So much, it was just like this. They would just die mid flight while you were driving. I mean, they were, you're crunching over them on the road. I mean, just so many cicadas, you can't even describe it. And cicadas come out of the ground every 17 years or every 13 years.
[00:01:55] And I'm going to get into that in this episode, as well as some other unfortunate animals that may die in your pools. And we're going to talk a little bit about that because we do get questions about it as sad as it is. But let's talk about what these cicadas and other animals might do to your pools. This is episode 141 of the Rule Your Pool podcast, and just listen to that.
[00:02:21] Let's go.
[00:02:25] Eric Knight: Every 17 years, these big, big bugs come back up out of the ground. Now, some people call them grubs when they're in the ground, or locusts, or whatever you want to call them. But these are big insects, they're about an inch and a half to two inches long. Big wingspan, red eyes, maybe green eyes, depending on the brood that you have. And they're everywhere.
[00:03:07] And cicadas serve some sort of purpose. I'm not exactly sure what they are, but when they come out, they have a survival mechanism. Because in 2021, I remember doing this research on them. Why are there so many of them and why are they so loud? Well, the way that cicadas evolved to survive is not by being agile or being smart. It's by overwhelming the predators and making sure that they can reproduce their species by simply having more numbers. They come out in the millions per acre.
[00:03:42] Let me repeat that. Cicadas come out of the ground every 17 or 13 years, depending on the brood, over a million per acre. In the areas that they've been in for a long time. Now, if you're in a new development, like new homes or whatever, you probably don't have many because bulldozers, when they cleared the land, probably got rid of most of the grubs.
[00:04:04] But if you're in an older neighborhood, like I am with big trees, just listen. I don't know how well the microphone picks it up, but there's this like loud roar that seems like it's two neighborhoods over. And then you can hear that high pitch rattling of the trees around me as well.. It's so loud that when I'm driving, I can hear it over the sound of the music in my car, even if the windows are up.
[00:04:32] But back to this, I wrote this article in 2021 because I grew up in Northern Virginia and I remember Brood 10, which is supposedly the biggest brood in the country. They come out, like I said, millions per acre. And I was really excited because I had moved to Charlotte and I said, oh my gosh, the cicadas are coming out.
[00:04:48] And the house at the time was in a very old neighborhood. And I knew that we were just going to get so many cicadas. Not one showed up. And then I found this map on the U. S. Forestry Service, and it's in this blog. Like I said, it's on our website. Just search the word cicada. Active periodical cicada broods.
[00:05:09] And I realized that Charlotte, North Carolina, where I live, is a completely different brood than what I'm used to in Northern Virginia. Northern Virginia brooded in 2021 and 2004 on a 17 year cycle, and Charlotte did not. Charlotte actually has brood 19, X1X. Or X, I, X, whatever you want to say, Roman numerals, brood 19, and it says 2024 on the map. And they're right, because just listen to this, they're here. And this is actually a brood that takes 13 years to gestate underground.
[00:05:44] Eric Knight: So essentially what they do is they come out of the ground, they shed their locust shell, which looks like a brown, well, it looks like a shell, almost like a shrimp. Honestly, they're pretty big.
[00:05:56] And then they climb trees or they fly up the trees and they get on these branches and they kind of dig a little cut or a trench into the branch. And that's where they lay their eggs and fertilize them. And that rattling you hear is sort of a mating call, I guess. And it creates this vibration that's very, very loud.
[00:06:15] And because cicadas are so high in protein and so slow and so meaty, so to speak, every bird wants a piece of these things. And apparently coyotes eat them. Turkeys eat them. Crows eat them all hawks and owls, and even the smaller birds, they just go nuts.
[00:06:34] And this is a very important part of the ecosystem, according to these sources, because it allows for certain other prey animals to have two to six weeks of not being eaten and not being targeted. Which is essential for their survival. Blows me away how well our ecosystem is just naturally constructed.
[00:06:57] I never would have thought this would be a thing, but according to these sources, it's very important that these cicadas happen.
[00:07:03] Eric Knight: Now that I have bored you completely with this biology lesson, what does this have to do with swimming pools? Well, I'll tell you. I'm sitting on my deck right now because I can't record in the house, it's just as loud. And I might as well be out here with the full noise.
[00:07:17] When you hear the figure over a million cicadas per acre, let me tell you what that means for a swimming pool. I have pulled out over 200 in the last day. I'm netting them out so rapidly and they keep getting into the pool, it's ridiculous.
[00:07:36] They're here for about two to six weeks and then they all die, but their eggs will grow. They will, I suppose gestate and they'll drop to the ground. Then they will burrow for the next 13 years. They'll come out and be just as raucous as these. But there are so many cicadas getting into the pool and I did not think that this would impact my pool chemistry the way it has. Now, granted, my water is perfectly clear.
[00:08:02] I'm using CV-600 enzymes. I use PR 10,000 once a month. I'm chlorinating once a week with a gallon. Last summer, I chlorinated twice a week, half a gallon in the middle of the week, half a gallon on Saturday. I'm actually just doing weekends now to see how that goes. And I'm about to renovate my pool. Thanks to our friends at Pentair for the equipment, and I'm going to drain and acid wash and MicroGlass this pool as well next week. So I don't really care if the water's trashed because I'm about to drain it.
[00:08:30] But I am paying attention to it. I pay very close attention to this pool. I'm not able to hold chlorine as well as I normally can.
[00:08:39] And I got to thinking, what changed? The only thing that's changed is the cicadas and a lot of them. I'm pulling out so many of these. So I did some research, like I said, back in 2021. What do these cicadas bring into the water?
[00:08:56] Eric Knight: Well, number one, when they dig into the branches, they get covered in tree sap. If you have a cicada that's already laid its eggs flying over your pool and it decides, well, now's the time to die. And they do, they drop right out of the sky and they land in the pool. That must be what's going on because I have so many. There's, they're everywhere. They're, they're on the railing.
[00:09:15] One of them landed on my computer before I recorded. I had to swat it away. And like I said, they're like two inches long. They're big bugs. So if you're squeamish on bugs, you're probably not going to like cicadas, but they're harmless. I've got just from what I can see here, just in about 20 square feet, I see 15 dead cicadas. So they're all over my deck. And if the wind changes, they're going to get blown into the pool.
[00:09:43] I am not able to hold chlorine very well. It's pretty astounding because nothing else has really changed. So I'm getting this tree sap in, but perhaps more importantly, there was a study in volume 28, number one, in the Journal of the North American Benthological Society. and I don't actually know what benthological means.
[00:10:05] It's called the deposition and decomposition of periodical cicadas in woodland aquatic ecosystems. Not going to bore you with the science, but essentially these decaying cicadas are very high in nitrogen, phosphorus, and carbon. Mainly nitrogen.
[00:10:24] So when they break down, they put a lot of nitrogen in my water, which would explain why I have combined chlorine. Because I'm not putting algaecide in there. I haven't even been in the pool yet. So I'm not in there peeing or anything like that. So, where is the nitrogen coming from? Well, apparently it's coming from these cicadas. Which, according to this, I guess makes sense. I never would have thought.
[00:10:44] Eric Knight: But here's the good news. Cicadas, so far, they don't sink. They're mostly in my skimmer basket. And I mean, you can't imagine how many are in my skimmer basket. And I'm netting them out because they float at the surface of the water. So, they're pretty easy to get out as long as you stay on top of it. But just in the last 3 or 4 days when these emerged, I've had, like I said, well over a couple hundred in my pool.
[00:11:09] You may have this too. Especially if you have older trees in your area, if you're in an older neighborhood, if you have cicadas in your water, you know, I mean, just listen to them. The birds are going nuts. The birds are getting all fat and happy eating these things like crazy.
[00:11:29] Eric Knight: Now, let's just talk briefly about other things that might get in your pool, as sad as it might be.
[00:11:34] The other day, I found two dead mice in my pool. They were floating too. I was able to net them out. What does that do for my chemistry? How about dead frogs? I have a few of those too. I think most pool owners can resonate that you're going to get unfortunately, some dead animals in there. And I guess if you had big animals, it would be a bigger concern.
[00:11:54] But most of these are little animals. Mice, bugs, frogs, hopefully not snakes, those are nasty. What do they do to pool chemistry? Well, it's safe to say, um, they're bringing some contamination in. How much? I don't know. But, uh, the sooner you can get them out, the better. So be netting regularly. If you see it, get the animals out.
[00:12:18] I don't have any issues with clarity despite having a filter issue, which. Is deliberate because I'm destroying my pool. But I'm chlorinating once a week. My water is crystal clear. I don't have any algae. And I think that's because CV-600 is doing the lion's share of the work. I could be wrong on that,
[00:12:36] I don't think two mice are going to make that big of a difference on my chlorine demand, but I'm sure they're not helping. Same with dead frogs or whatever else. So let's just try to stay diligent, clean your strainer basket. If you see something, remove it with the net.
[00:12:50] It's one of the best things you can do because there is no replacement for getting rid of solids, basically. Physically removing things is always going to be a good idea.
[00:13:02] Eric Knight: Anyway, I, this is not really a planned episode 1 if you can tell, because I just wanted to seize the moment. It's so loud it's deafening. Why not take advantage of the noise? And a beautiful day to record outside? It's been raining for a few days and now it's sunny.
[00:13:21] This has been episode 141 of the Rule Your Pool podcast. I'm your host, Eric Knight with Orenda. If you have some podcast topics or little one-off unique situations that you'd like some help with, email me, podcast@orendatech.com. You can also visit our help center and our blog.
[00:13:39] Our help center is ask.orendatech.Com. That's ASK.orendatech.Com. And our blog is blog.orendatech.Com. Lots of information on there. There's a good chance that we have talked about what you're asking. But every so often people will give us a great idea of something to research and look more into.
[00:13:57] We appreciate all of you. We do this show for you. Thanks for listening. Thanks for putting up with me for 15 minutes. Get on with your season. Enjoy ruling your pool. Take care, everyone.
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