Short Wave

What drives animals to your yard? It's complicated

14 min
Jan 27, 20263 months ago
Listen to Episode
Summary

A listener in suburban Atlanta reports an explosion of lizards and frogs in her yard over the past few years. Scientists explain that these common, native species thrive in urbanizing areas with suitable habitats like water features and vegetation, and discuss both eradication and coexistence strategies for managing wildlife in residential spaces.

Insights
  • Urban wildlife population changes may reflect habitat shifts rather than actual population increases, highlighting the need for long-term community science monitoring
  • Human development fragments amphibian habitats, forcing species into residential areas where they become more visible to homeowners
  • Creating dedicated wildlife zones in gardens can reduce human-wildlife conflict while providing pest control benefits through natural predation
  • Outdoor cats kill millions of frogs annually in some regions, representing a significant but controllable human impact on local reptile and amphibian populations
  • Proximity to water features within 100 yards dramatically increases the likelihood of encountering amphibians in residential yards
Trends
Urbanization driving wildlife habitat fragmentation and species displacement into residential areas across multiple regionsGrowing adoption of community science programs to fill data gaps in long-term amphibian and reptile population monitoringShift toward coexistence-based wildlife management in urban environments rather than eradication approachesIncreased awareness of outdoor cat predation as a quantifiable threat to local amphibian and reptile populationsIntegration of native plant landscaping and temporary wetlands as urban ecological management strategiesRecognition that human-created features like pools and ponds significantly alter local amphibian distribution patterns
Topics
Urban herpetology and reptile-amphibian ecologyHabitat fragmentation from residential developmentCommunity science monitoring programs for wildlifeNative plant landscaping and wildlife habitat creationHuman-wildlife conflict management in suburban areasOutdoor cat predation on wildlifePesticide impacts on amphibians and reptilesWetland and water feature ecology in urban settingsWildlife population monitoring methodologiesInvasive species versus native species identificationSuburban ecological change and urbanization effectsAmphibian breeding habitat requirementsPest control through natural predationUrban ecological coexistence strategiesGeorgia reptile and amphibian biodiversity
People
Daniel Salenberger
Senior wildlife biologist with Georgia Department of Natural Resources who identified species and explained habitat p...
Mara Dudley
Biology professor at Oakville Thorpe University and urban ecologist for the amphibian foundation in Atlanta leading c...
Shabnam Khan
Listener from Lawrenceville, Georgia reporting increased lizard and frog populations in her garden over several years
Quotes
"The things that are using her yard in Lawrenceville are very adaptable, common things. Things that can tolerate a wide range of conditions."
Daniel Salenberger
"If your listener loves to garden, then she is probably benefiting significantly from having snakes or frogs in her garden because they are some of the biggest consumers of insects and other pests."
Mara Dudley
"Just because she's seeing them more often, doesn't necessarily mean there's a population increase that there's more of them."
Hannah Chinn
"What we gain in real estate, animals lose in habitat."
Mara Dudley
"It's estimated that up to 92 million frogs were killed per year by cats in Australia and there have been some similar studies and kind of numbers that are coming out for the United States as well."
Hannah Chinn
Full Transcript
Support for NPR and the following message come from the William and Flora Hewlett Foundation. Investing in creative thinkers and problem solvers who help people, communities, and the planet flourish. More information is available at Hewlett.org. You're listening to Shortwave from NPR. Hey everyone, Emily Kwong here with Producer Hannah Chinn. Hey, Emily. Okay, so I've been looking into a question from one of our listeners in Lawrenceville, Georgia, which is a suburb about 30 miles outside downtown Atlanta. It's very pretty here in Atlanta. Lots of hills and very green when you're landing at the airport. You can see just a green canopy all over the city. So this is Shabnam Khan. She's lived in and around the area since 1986. And clearly she really loved the place she lives. Partly because it's so lush. Yeah, Atlanta is beautiful. It's also subtropical. So I imagine there's lots of plants that thrive there. Exactly. Which is great for Shabnam because she loves to garden. But there's one problem with her garden, Emily. A problem that's been visiting pretty regularly that started small. A lizard here and there. And it's just not going away. I do gardening quite a bit. And now last two or three or four years, every time I'm gardening, every time I'm working in the yard, I get scared by lizards and frogs. Oh no. And there are many of them and lots of different varieties like stripes and like beautiful colors, but I'm still scared of them. Shabnam told me she doesn't even want to be in her garden anymore. She's so stressed out by this spike in garden visitors. And she says it's not uncommon for her to hear an army of frogs croaking in her neighborhood at night or to find multiple brightly colored lizards sunning on the grass. And now she's like, where did all of these come from? It's just the quantity boggles, my mind. Just the population seems to have exploded. Today on the show, we are going on a lizard hunt. We're talking to local experts about why so many lizards and frogs are showing themselves now. And whether there's a way to manage Shabnam's clammy, scaly, little problem. You are listening to shortwave. The science podcast from NPR. This message comes from Wise, the app for international people using money around the globe. You can send, spend, and receive an up to 40 currencies with only a few simple taps. Be smart, get Wise, download the Wise app today or visit Wise.com, tease and seize apply. Support for NPR and the following message come from the William and Flora Hewlett Foundation, investing in creative thinkers and problem solvers who help people, communities, and the planet flourish. More information is available at Hewlett.org. Okay, shortwaveers. Once again, we are on a nature quest. This is our monthly segment bringing you a question from a fellow shortwaveer who's paying attention to their local environment and how it's changing. And this month, Emily, you and I are investigating the world of herpetology. Frog, snakes, lizards, salamanders to help out our listener, Shabnam, in Georgia. I love it. Okay. So first things first, to start this nature quest, I needed to know what specific frogs and lizards Shabnam was seeing in her yard. Naturally. There are around 180 reptiles and amphibians native to Georgia. So I kind of needed to narrow it down. So I asked her to send me some pictures. Emily, I'm sending them to you right now. Okay. Do you want to describe these little creatures for our listeners? So this one, it's like a peacock lizard that has this pink throat sack hanging from his little lizard head. Yeah, the top animal is the green and all. That's one of our most common lizards. Found pretty much statewide. Really common in gardens and home areas. Then I'm looking at, woo, I really like this. It's a salamander with like an electric blue tail. It is one of our skinks, probably a five line skink, but there's a couple of species that look similar. Green tree frog. That's so this is Daniel Salenberger. And he's a herpetologist and senior wildlife biologist with the Georgia Department of Natural Resources. He identified these animals very quickly. I guess this is what he does for a living. So, but could he tell you anything else about them or why they might be populating shop numbs yard? Yeah, he did. The things that are using her yard in Lawrenceville are very adaptable, common things. Things that can tolerate a wide range of conditions. They're fine living in neighborhoods and homes. They can live under the deck on your porch or clump of cat tails next to a retention pond. Basically everywhere. Okay, so these are not invasive lizards and frogs. It appears not. No, they're just super common. But shop num also said she's seen increasingly more of these critters. So, Daniel, tell you why that might be. Yeah, I asked him that too. You know, I guess I would ask her, is anything changed in your neighborhood or your yard in that period of time? You know, there are things that you can do in your yard intentionally or unintentionally that tend to make better wildlife habitat. Things like not mowing your grasses often or planting more native plants. Maybe putting in a water feature like a fountain or a pond. You know, like if you put in a goldfish pond in Metro Atlanta, you're going to get tree frogs and stuff using it. Oh, duh. Right, amphibians love water. Right. And other local experts told me this too, like Mara Dudley. She's a biology professor at Oakville Thorpe University and she's also the urban ecologist for the amphibian foundation in Atlanta. What species might actually be found in your listeners area is going to depend a lot on the habitats that are present. And primarily, is your listener within about 100 yards of a body of water is going to make a big difference in terms of what species they might find. So even a pool, a block away could be contributing to what Shobnam is seeing in her yard. Yeah, totally. It's like the length of a football field. So what can she do then to avoid seeing more lizards and frogs in her garden? Daniel and Mara told me there's two different ways to kind of go about it. There's the full eradication approach basically making your yard as inhospitable as possible to any animal. Uh-huh. So things like cutting your grass very frequently, keeping it very short and neat. If you have flower beds around your home, either don't have those or keep the shrubs and things trim. So there's there's not layers of vegetation all the way to the ground. Make sure you don't have any rock piles, piles of limbs, piles of leaves, things like that. Just places for animals to hide. These are all terrible ideas, in my opinion. But if you want to see less wildlife around your home, have nothing but concrete inside, and you'll see a lot less stuff. Yeah. Which Daniel does say comes with trade-offs. Now keep in mind, when you're creating or destroying wildlife habitat around your home, it's hard to control what you're going to see. So for instance, if she really likes the birds, well, this is going to maybe decrease the amount or diverse the birds you see too. So that's the eradication approach. So that's the eradication approach. And then there's the sharing is caring approach. I'll say this to your listener. They probably don't want to see her as much as she does not want to see them, right? Because any large organism is going to appear to be a predator to any kind of amphibian or reptile in the area. Because Emily, these reptiles and the amphibians, they want to hide. So Mara suggested build a spot for them to do that, rather than tearing rocks and native plants out completely. Just put them in a separate part of a garden, the part that maybe Shabnam doesn't garden it. So create like a little amphibian sanctuary in a dedicated spot of the garden. Yeah, exactly. And Mara says this gentler approach, it has benefits for people too. If your listener loves to garden, then she is probably benefiting significantly from having snakes or frogs in her garden because they are some of the biggest consumers of insects and other pests like mice and rats and chipmunks that might be assuming things in her garden. I feel like this is a whole perspective shift on amphibians in Atlanta from these these herbitologists. They're like, I mean, I may not be so bad. Yeah, exactly. Of course, I imagine this is happening in other places, not just Atlanta, where someone is noticing their garden being frequented by more and different animals. Are there larger trends in urban wildlife? Like, can we link what's happening in Shabnam's yard to a like bigger ecological rise and fall in urban lizards and frogs? Mara told me to some extent, yes, the shift in wildlife that we're seeing goes beyond the greater Atlanta area. It's happening in all these places that are urbanizing because what we gain in real estate, animals lose in habitat like in South Florida, where developers continue to push the Everglades boundary or subdivisions and ranches in the greater Yellowstone area. If you move into a given area and there is a low amount of development around you and over time, the demand for housing increases, what that means is all of these pockets that are natural areas tend to be then taken up and developed. And what that means is that what was potentially suitable habitat for a lot of amphibians and reptiles now is no longer suitable and those species have to move. Right, because if they lose their habitat, then they got to go somewhere and that somewhere could be places that people are. Yeah. And Mara said this is just one of a few ways that human development can affect local amphibians. Another way is fragmentation. Particularly when it comes to amphibians, these species that live in terrestrial ecosystems most of the year and breed in freshwater ecosystems, if there's now a road that is going through that connection in between, that puts a lot of species at greater risk for mortality. Mara also mentioned human use of chemicals like pesticides that are really bad for amphibians and reptiles. Yeah. And then there's the issue of the predators that humans bring with us, like outdoor cats. Mara likes to cite a 2020 study about this. It was estimated that up to 92 million frogs were killed per year by cats in Australia and there have been some similar studies and kind of numbers that are coming out for the United States as well. It's in the millions. That's just frogs. Oh, dear. That number doesn't count snakes, salamanders, lizards, other animals that are also killed by cats. Honestly, this doesn't surprise me. Cats are, they're adorable. I have one and they're meant to kill. They are. But the good thing is, Emily, these things can work in reverse as well, right? So just as human development can hurt reptiles and amphibians, it's also pretty easy for humans to help them. Like planting native plants and removing invasives or avoiding pesticide use, keeping our cats inside and then supporting temporary wetlands like ponds and marshes wherever they crop up near us. So what I'm hearing from you, Hannah, is there is so much we can do to help amphibians in our neighborhoods. Yes, totally. And there's actually one more aspect of Shemnam's question that I want to get into, Emily. This idea that she's noticing more lizards and frogs because Mara and Daniel told me, just because she's seeing them more often, doesn't necessarily mean there's a population increase that there's more of them. Okay, but how can we don't know? Because there's still a big gap in local scientists' data. And that's because long-term studies monitoring the populations of these species and metrolana really just don't exist. So Mara is trying to change that through community science. So the community science program is called the Metro Atlanta amphibian monitoring program which we like to refer to as MAM because that's quite a mouthful. And Emily, anyone in the Metro Atlanta area can apply to be a community scientist in this MAM program. Mara and her colleagues will train them to identify each species in the field and document their findings and then volunteers have to take a series of quizzes to basically show that they retained all that information. This is like school. I mean Emily, you love school. I do. History. Anyway, there's an online signup forum for trainings and program news. We'll link to it in the show notes. And if you, like Hannah and I are not in the Metro Atlanta area, but still want to learn how to identify and document local frogs, consider seeing if you have an active local frog watch chapter. Search your city or state and frog watch USA. Thank you so much for guiding us through this month's Hoppy Hippity Nature Quest, Hannah. Anytime Emily. Short rivers, if you want to get in on this Nature Quest series, it's so easy. Look around your environment. Is anything changing or do you have an environmental question? You want us to investigate? Well, record a memo and email it to us at shortwaveatNPR.org. And we may look into it for a future episode. This episode was produced by Brillie McCoy with help from Rachel Carlson. It was edited by Rebecca Amiris. Tyler Jones checked the facts. The audio engineer was Jimmy Keely. Sam Polson composed and produced our Nature Quest theme music. If you like this episode, follow us on the NPR app or wherever else you get your podcasts. I'm Emily Kwong and I'm Hannah Chan. Thank you for listening to shortwave from NPR.