April 6, 2023 — Dr. Kelly Diehl sits down with turtle and tortoise experts Dr. Justin Perrault of Loggerhead MarineLife Center and Dr. Greg Lewbart from North Carolina State University to discuss the health threats affecting wild turtles and tortoises and learn more about their efforts to improve the well-being of these unique, and often over-looked, animals.
Resources:
Learn more about all the Foundation's turtle studies https://www.morrisanimalfoundation.org/search?search=turtle
Dr. Perrault's study publication
https://www.nature.com/articles/s41598-021-03550-y
Loggerhead Marinelife Center
0:00:08.8 Dr. Kelly Diehl: Welcome to Fresh Scoop episode 55, Tackling diseases affecting fresh water and sea turtles. I'm your host, Dr. Kelly Diehl, Morris Animal Foundation, Senior Director of Science and Communication. And in the first half of today's program, we'll be talking with Dr. Justin Perrault. Dr. Perrault is Director of Research at Loggerhead Marinelife Center. Welcome, Justin.
0:00:31.3 Dr. Justin Perrault: Hi, thanks for having me. I'm excited to talk to you.
0:00:34.1 DD: Great. I always ask people when we start, tell us a little bit about yourself and what led you to your PhD and then your current work?
0:00:44.0 DP: Yeah, so I grew up in Memphis, Tennessee, sort of land-locked unless you count the Mississippi River, so we didn't really have much marine life around us. But we grew up in a house where all animals were welcome, and spiders were friends and snakes and things like that that a lot of people don't like. So, I had this kind of upbringing that gave me almost this inherent interest in nature. So, then I went to North Carolina and got my undergraduate in Marine Biology, and the sea turtle aspect was just a luck of the draw kind of thing. I procrastinated applying to graduate school, and the one school that I got into just happened to be with sea turtles. And that's how my journey into the marine environment and sea turtles in particular began was just kind of luck. And ever since then it's not a regret at all.
0:01:46.5 DD: Oh, great. Yeah, full disclosure. I think I probably never told you this, but turtles, I'm not a reptile person, but I love turtles, tortoises. We took care of my son's classroom tortoise one summer, which was a whole experience. So, you just talked about this a little bit, but are you especially fond of sea turtles? And what's the most interesting or intriguing aspect of working with these animals?
0:02:14.9 DP: I do like sea turtles quite a bit. A lot of us, see, I think a lot of people that specialize in certain animal groups, it's part of their identity, and we as sea turtle biologists work really weird hours. We're either up very early in the morning or very late, up all hours of the night when everybody else is asleep. And for some reason, we just keep torturing ourselves doing this with these animals. I'd say my favorite part about the sea turtle, and I say this often, is they're such resilient animals. People think a lot of times they're these little cute hatchlings that hatch off the beach and they scurry to the ocean, and there's all these myriad of predators that they have to skirt around and dodge and survive past on top of all the human impacts that are out there as well.
0:03:08.1 DP: And it's just these animals that are able to survive with all of these threats. So, we'll see animals that come up on the beach to nest with pretty nasty boat strikes that are still nesting and completing the nesting process and doing that multiple times across the season. And I think that resiliency creates a lot of respect for animals like that because they're just really able to push through and power through regardless of what's thrown at them.
0:03:35.5 DD: Well, that's a good point that I wanted to ask you about, which is, I think we lump sea turtles into one giant group, sea turtles. There's lots of different species. So can you speak a little bit to the number of species. Are they endangered? Are some not endangered? Again, you talked about boat strikes, but what are some of the threats to sea turtles?
0:03:57.1 DP: Yeah, so there are seven extant species of sea turtles. A lot of them... We have about six of the seven species here in the State of Florida at least locally in our waters. So, the only one that we don't have here is the Flatback, which is native to Australia. And six of the seven species of sea turtles are either vulnerable or threatened, endangered or critically endangered. And then the Flatback, I believe in Australia is considered data deficient, so we don't really have a good sense of the population size of those animals. But in terms of threats, you name it, it's really anything that any of the rest of the animals on Earth are facing, but some of the biggest ones, in my opinion, I think are obviously plastic ingestion. I work at a sea turtle rehabilitation facility, and 100% of our patients that come in have ingested plastic in some form which isn't necessarily deadly if they ingest it, but for the smaller life stage classes, we see some issues.
0:05:00.5 DP: Honestly, boat strikes, particularly in the State of Florida where we have more boater registrations than anywhere in the nation, are just a major threat to our animals here. Climate change and sea level rise are also another one. As the Earth warms, that creates a lot of problems for reproduction and sex ratios of the hatchlings that are emerging as well as loss of suitable habitat for the nesting site. And in certain areas of the world, there's still take of these animals for human ingestion as well as a lot of interactions with fisheries. So, there's quite a few threats and the natural threats are like shark predation and other predations are much lower than you would see with some of the anthropogenic or the human threats.
0:05:54.1 DD: Okay, so that's interesting. So, there are only seven species. Are they pretty widely distributed or are there pockets of sea turtles where they inhabit the environment?
0:06:06.9 DP: Yeah, so like I said, the Flatback is mostly native to... Is native to Australia. We don't get that species anywhere else. They only nest in the country, that country. You've got other species like the Kemp's Ridley which are very highly endangered, one of the most rare species of sea turtle. And their only nesting grounds are really in Mexico, one place, a couple of places in Mexico, and then there's a smaller nesting population in Texas. However, you do have on the opposite end of that, you've got species like the Olive Ridley Sea turtle, which is the most widely distributed sea turtle on the planet. And then you've also got the Leatherback turtle, which is able to really inhabit places in the Earth that you wouldn't think any reptiles would be able to inhabit. So, we actually have one now that was satellite tagged that was foraging up off of Nova Scotia. So, you think a reptile on a very cold environment like that is impossible, but not for the Leatherback.
0:07:08.4 DD: Wow, that's amazing.
0:07:09.7 DP: Yeah, that's really cool.
0:07:10.6 DD: Their name sounds very rugged, doesn't it? [chuckle] It's a good...
0:07:13.2 DP: Yeah. Yeah, they're my favorite. They're close to my heart is what I did in my PhD on is, that species, and they're just so cool.
0:07:21.3 DD: Oh, that's pretty funny. So, let's talk about your project funded by the Foundation because this was different than what we've just talked about a little bit. So, can you give us a quick summary of the problem you were addressing and a brief overview of your project?
0:07:37.5 DP: Of course, so we in the State of Florida in particular and also worldwide, there's things called red tides. In the State of Florida, we have a specific red tide that's caused by a harmful algal species. It's a dinoflagellate known as Karenia brevis, and it produces these potent neurotoxins that are released into the water when you've got these blooms of red tide, which are a naturally occurring phenomenon. However, after a lot of storms and run-off events and things like that, we often see large blooms of these red tides because essentially they're tiny little plants that like fertilizer. And so, if there's a lot of that in the environment, we'll see these red tides.
0:08:23.3 DP: And what happens with red tide is these neurotoxins release into the water, and you'll see a lot of animal impacts. Like fish kills are the first thing that you notice because the fish just... The toxin just eventually just gets them first just due to their general physiology, but then you'll see a lot of other problems with other animals. You'll start to see strandings of birds and sea turtles and marine mammals and some of the larger fish species as well. So, there's no real way to combat this because it's natural. So, what we wanted to kind of do was to see if this treatment that's really common in human drug overdose cases would be useful in sea turtles in counteracting these neurological problems that we see as a result of red tide poisoning.
0:09:21.3 DD: Okay. So, talk about your findings and what you used on these guys because it's pretty interesting.
0:09:30.4 DP: So, what's cool is you're talking to this freshwater person or this turtle person, this regular turtle, we'll call him person next. And so, what we used was, it's a drug. It's intravenous lipid emulsion. It's just some lipids that go directly into the bloodstream, and because sea turtles have this endangered status, we had to make sure at first that it wasn't going to be harmful to the animal to just give this drug. So, the first portion of this study was actually done in the red-eared slider to make sure that there were no negative effects and to make sure that it worked. And that study really showed everything we thought. The brevetoxicosis as we call it, or the poisoning, was really declining in those, that model species.
0:10:17.3 DP: So, then we moved on to sea turtles, and we have... I guess, lucky for this study, we do have quite a few red tides that occur in the State of Florida, so we got some sea turtles that came in alive that stranded with brevetoxicosis around the West Coast of Florida. They went to the Clinic for the Rehabilitation of Wildlife in Sanibel. And as soon as they came in, what we did was give them this ILE directly into the blood stream and then took blood samples at time zero when they came in before the drug, and then at one hour, two hours, six hours, 24 hours and so on. And we wanted to look at a few things, survival, how the toxin declined as a result of the ILE in relation to other studies that just use standard and supportive care with no drugs, and then also release times.
0:11:10.7 DP: So, what we found was that survival increased by 50% over traditional methods, so standard and supportive care. We saw no negative effects as a result of delivery of the drug in these animals and release times didn't really change because that's kind of hard to measure because sometimes you still have an active bloom in the area, or they have secondary conditions that you have to treat. So, the release times didn't really differ, but we did see a much faster decline in the toxin from the blood than we saw with turtles that were treated with standard and supportive care. So, it was really a win-win treatment.
0:11:51.8 DD: Yeah, this was a really cool study. And for those people who are listening, I know the veterinarians and vet techs probably recognize this because we use it in dogs and cats for toxicity. So as Justin mentioned, it was developed for people with, I think, overdoses. But also, other just drug, it doesn't have to be necessarily an opioid overdose. We use it a lot for people who use... Who know Ivermectin there for dogs and cats. Yeah, we use it for heartworm treatment and people probably have heard a lot about Ivermectin with COVID. But we do see overdoses, usually dog eating horse because actually we use it in horses. And it can be pretty bad. Yeah, it's a neurotoxin, and so that is one of the things that jumps to mind. But this is really a cool use of this drug that I think is pretty safe. It sounds like in turtles and in people and animals, dogs, and cats. It's really cool. You got a lot of press, I think. [chuckle]
0:12:56.4 DP: We did. People love sea turtles, and so if you've got a study like this that's like, "Look, we're saving sea turtles with this human drug." It did get quite a bit of press, which I think is wonderful. We were able to figure out almost a cure for something that is natural, and we really can't do anything about in the local environment because we can't control red tides. So, it was a way to kind of show that we can't fight the cause, but we can fight the symptoms and...
0:13:35.2 DD: Right. Right. So do you know of anyone else using this treatment. Have you heard anecdotally or...
0:13:43.5 DP: Yeah, so like you said, the paper got a lot of press, so I think it put this drug on the map. And so, I know particularly at Crow, there was a lot of use with this in seabirds, particularly the cormorants are susceptible to brevetoxicosis. And they saw increases in survival with those animals, and people are using it here and there. What's I think cool about it is in turtles that have come into our facility on the East Coast where we don't really have a lot of red tide, they're just giving ILE to animals that are neurological with the unknown origin. So, it could be another type of algal bloom. It could be some other thing that they've ingested, and oftentimes ILE is the first thing that vets will think of to give because it's again not harmful to the animals.
0:14:40.8 DP: So, it's used here and there, and like I said, I know it's been treated... Used in birds and other sea turtles on the West Coast of Florida and other facilities. And I think what it showed is that this drug is safe to give regardless of if it's brevetoxin or even if you're not sure because essentially you're just giving the turtle a little bit of fat and the turtle metabolizes that normally.
0:15:05.0 DD: Right, right. And for those, I think, the veterinarians listening, we tend to give oral charcoal all the time to animals as a binder when we don't know what they've ingested. Tell us a little bit about some of your other research projects because I know that one's done, but you're busy, busy, busy.
0:15:25.1 DP: So, we have a really busy nesting beach over here on the East Coast of Florida. We're the most... We monitor an 9.5-mile stretch of beach in Northern Palm Beach County, and we are the most densely nested Loggerheads sea turtle beach in the Western Hemisphere. We're second only in the world to some beaches in Oman, and so we do... We also have tons of Loggerheads, but we also have a lot of green turtles, and we also get quite a few Leatherbacks nesting on our beach. So, it's a really cool area to do a lot of research. Some of the things we're doing are... Some of my favorite projects are with satellite tracking of these animals. So, we're placing satellite transmitters on nesting leatherbacks and nesting Loggerheads to see where they go when they leave the nesting beach, so we can better understand habitat use and maybe overlay threats with where they're hanging out.
0:16:20.4 DP: And with the Loggerheads in particular, we're finding that they're laying a lot more nests than we thought that they did. So, our average nest number that a Loggerhead is laying in a single nesting season is six. And previously we thought it may have only been three to four, so what that's showing us is that we way overestimated our populations, our nesting populations, because you divide your number of nests divided by clutch frequency is what we call it. And so, what this is showing us, at least on the East Coast of Florida, is that we have way fewer Loggerheads than we actually thought. We always do some other stuff. We always do basic health assessments of these animals every year that are nesting on our local beaches. So, we're taking blood from nearly every animal that we encounter and doing baseline health analysis just to see how those change over the season or to see how those change annually in relation to environmental disturbances.
0:17:19.3 DP: We do a lot of chemical contaminant work, so looking at a lot of heavy metals by foraging area where these animals are and maybe we can create some ways to mitigate release of those compounds. And the studies are endless. Because we have so many animals, we do quite a bit every year, and we're always willing to work with graduate students and veterinary students every single year to come up with projects that they might be interested in.
0:17:47.1 DD: That's cool. Just a little commercial for you guys. In the show notes, everyone who's listening, I'll put a link to the Loggerhead Marinelife Center because you do lots of cool things. And am I right that you take... Do you have volunteers who do some of the nest counting like when you have hatchlings or no?
0:18:10.3 DP: Because our research program is so intense, so like I said, we have 9.5 miles of beach. We had over 18,000 nests on that 9.5 miles this year. So, we don't really like to ask people to do that for free. So, in my department and the research department in particular, we take undergraduate and recent graduates every year and give them seasonal work for our department. However, the Loggerhead Marinelife Center is multi-faceted. We have a conservation program. We have an education program, and we also have a rehabilitation program. And all of those other departments take volunteers. We have over 350 volunteers at the facility. And again, since this is kind of geared towards veterinarians, we take veterinary interns, veterinary externs. We are a teaching hospital, so if you've got people out there that are interested in wildlife, send us an email because we're getting busy again. We've got, I think, nine sea turtle patients at the moment, and science is all about communication and collaboration and learning from one another, and that's what we really love to do, and that's one of the goals of our hospital team as well.
0:19:25.8 DD: Right, and you get to go to North Palm Beach, is that correct?
0:19:30.5 DP: Of all the beaches I've lived at in the State of Florida, North Palm and Juno and Jupiter beach, they're very nice beaches, we've got a lot of beautiful blue water, we've got a nice... A lot of wave action, so if you like to surf, we've got a really cool pier, all kinds of stuff.
0:19:52.9 DD: It sounds like a great, great place. Well, that's really great to know. We get asked a lot about volunteer work, and we don't... We're just like a building with cubicles [chuckle] just giving grants out, but it's always great to be able to help, because I think people do want to help. And sea turtles are really charismatic species, so that's great. You talked a little bit about this, but are there any other big questions that you're thinking like, these are where we need answers when it comes to sea turtles and health?
0:20:30.6 DP: Yeah, I think one of the things that we're starting to investigate is health by foraging ground, so where are these animals going when they're leaving the nesting beach and how does that impact their overall health? So that's something that we're examining with our satellite tagged patients... Or not patients, our satellite tagged nesting turtles. And so, we've got some turtles that leave the nesting beach and some of them go up to the Chesapeake Bay area, we've got a few that are a little bit smarter and go down to the Caribbean for their time off. And then this year, we actually had a few that threw us for a curve ball. We have some that go to the Keys and actually some that go over to the West Coast of Florida.
0:21:10.7 DP: And what was kind of cool is we had one turtle this year that we ran her blood chemistry panel, and I said, "This doesn't match the other animals." I said, "I bet this turtle forages somewhere different." And sure enough, she went over to the West Coast of Florida, which is our first time that we had seen that. So, what we're seeing is that animal health definitely is influenced by their environment, which we know, but now with these studies, we can see that. I think the other major health question in sea turtles that's obvious for any sea turtle person is this virally linked disease called fibropapillomatosis, it's linked to chelonid alphaherpesvirus 5.
0:21:53.4 DP: In the State of Florida in particular, we have quite a high incidence of this disease and it primarily affects green turtles, and we don't really know why, we know that the disease evolved with the green turtles, so it's more susceptible than the other species, although all the other species can get it. But with this virus, it's linked to this virus, but Koch's postulates haven't been fulfilled to necessarily say that this is 100% for sure the reason that this happens. And certain other areas of the world have no incidents of FP, and a lot of those areas are pristine, but some of them are not, so these environ... That's something that we're looking into now with some collaborations, is environmental influences of this disease. And some people have done it other places, and not much has been found.
0:22:41.9 DP: So, it's a question that's been around in sea turtles for over 100 years now when we first documented this disease. But it creates these debilitating tumors on the animal, it's not a death sentence. A lot of the turtles that have the virus or that have the tumors are healthy outwardly, or at least inwardly based on their blood, healthy. So, it's not necessarily a death sentence, but it is extremely transmissible from... Horizontally transmitted from animal to animal and just there's still a lot of questions that we don't know. because these animals can't talk to us to tell us what's going on, so that would make things a lot easier.
0:23:20.4 DD: Right. So, does FP make it hard for them depending on where the tumors arise too for locomotion or eating or all of the above?
0:23:29.8 DP: All of the above. So, a lot of times, you find turtles with just little tiny tumors and the tumors can regress on their own without treatment. If the turtle comes into rehab, we can laser them off. But the problematic tumors, if a turtle has tumors that have internalized, that's basically a death sentence. The other problems with some of the tumors are if they occlude the eyes, so vision, so that obviously impacts their feeding. And then some of these tumors are four to six inches long and might be on the shoulders or in the arm pit, the arm pit area or the hind limbs and just impacts their ability to swim and feed, as you said.
0:24:11.6 DP: And so that's really the problem is what we've found recently is the immune system is not suppressed prior to getting the disease, what happens is immunosuppression occurs as a result of the disease. So, they can fight it off, and we really only see it in these younger life stage classes, and as they get older, we don't really see it at all in those larger animals, but the biggest problems are physical impacts.
0:24:41.6 DD: Okay, yeah, it's kind of interesting. I think as a Foundation, we've funded a few or I've seen some of those grants start to come across more in the wildlife sector, so that's kind of interesting. I think those of us who do small animal, we think of warty growths on dogs, like the little old poodles come in when they've got a million... So, this is that...
0:25:04.2 DP: That's what it looks like
0:25:05.4 DD: Yeah, but obviously this is a lot more serious for these guys than... because I have yet, knocked on wood, ever seen a dog that really... Other than cosmetically and these things bleed, that they don't... They live with them just fine. It's pretty interesting about the... And unfortunate for the turtles, so as we wrap up, what's your take home message for our listeners as far as sea turtles and sea turtle health and what they can do?
0:25:33.0 DP: I think just something I like to say is that, with all the crazy things going on in the world and all the plastic that's out there and all the negative things that you hear, I think it's really important to realize that we as conservationists realize that conservation is a compromise, and in order for humans and animals to live together in unison, we have to protect the environment for them. And when we see these drastic changes in the animal health, that is not indicative often of a healthy environment.
0:26:07.7 DP: And particularly with a sea turtle, it's a sentinel for humans because they're eating a lot of the same things that we eat, so if we're seeing unhealthy turtles, that's likely an unhealthy environment, and that translates to humans because sea turtles can't live in an unhealthy environment, but neither can humans. So, we really have to work together and be very conscious of our decisions. It's impossible to eliminate plastic from your life, but you can do little things here and there and make small changes in your life to make sure that the environment is sustainable for our future generations and the future generations of sea turtles and other wildlife.
0:26:41.9 DP: So, I think that's kind of something that I think puts it into perspective without sounding like a huge tree hugger and realizing that you have to compromise here. Humans have to live here, but animals need to live here as well, and they're very important for ecosystem resources and human resources and eco-tourism, and all of these things that disappear if our environment goes downwards. So, I think that's kind of my spiel.
0:27:12.5 DD: Well, that's great. So that wraps up this part of our interview. So, thank you so much, Justin, for coming on and talking to us about... This is always fascinating. I love talking with Justin, I've talked to him a couple of times about sea turtles and thank you for talking about your work and what people can do to help sea turtles.
0:27:32.5 DP: Always. It's always a pleasure to talk to you as well, any time.
0:27:37.4 DD: Welcome back to the second half of our podcast on turtles and tortoises, and I'd like to introduce Dr. Greg Lewbart. Dr. Lewbart is Professor of Aquatic Animal Medicine at North Carolina State University. Welcome, Greg, and thanks for coming on the podcast.
0:27:53.1 Dr. Greg Lewbart.: Thanks, Kelly.
0:27:56.2 DD: Before we get started, can you tell us a bit about yourself? What led you to become a veterinarian and then move into exotic animal medicine.
0:28:05.7 DL: Yeah, sure. So, like you, I'm from New Jersey, and I grew up in suburban New Jersey. Oldest of four boys, my dad's a physician and organic chemist. And really, it was... We had a cat and the cat got hit by a car and went to the local one-doctor practice, and Dr. Phil Bookman was one of the veterinarians that our family used. I think the cat was actually treated by another veterinarian. But I said, "Hey, I really like this veterinary thing," I was always fascinated with animals, and I worked for Dr. Bookman all through high school, and decided I wanted to be a veterinarian. College was a little bumpy. I don't think I was ready for the rigors of a science major curriculum, but I stuck with it, and in order to get into school, veterinary school, I needed to improve my academic standing, so I went to graduate school in Boston and mostly studied marine biology for my thesis, and that's what sort of merged marine biology, aquatics and veterinary medicine in my mind. I always loved reptiles and amphibians, and through my being in Boston for a few years and volunteering at the aquarium and working in Harvard's Herpetology Department, I thought, "Hey, I think I could do this as a career." And then...
0:29:53.4 DL: So that's sort of what tracked me. And really in veterinary school, I really was aiming for aquatic animal work with the idea of more marine mammals and sea turtles, which aren't easy to get your hands on when you're a student, but I took a job in a little pet store in West Philadelphia scooping fish in the afternoons, and that led to a job out of school with a local regional wholesaler of tropical fish. And I did that for about four and a half years before coming here to NC State.
0:30:29.2 DD: Oh, cool. So, I said this earlier, and you and I were talking about this before we started recording, which is that turtles are like my hands-on favorite reptile, or one of our former researchers who I won't out with the statement said, "They're the bright spot of the reptile world." [chuckle] But what is the most intriguing or interesting aspect of working with turtles in general, and maybe freshwater turtles and tortoises specifically?
0:31:00.3 DL: Yeah. Well, I think from a veterinarian standpoint, they are little tanks, they're really tough. I was just an hour and a half ago looking at a box turtle that had prolapsed from its vent. I won't get into the gory details, but... And the turtle just looked pretty stoic, like nothing was going on. And a couple of veterinary students and an intern were working with the case. And you really have a lot of latitude working with these animals, it's not like a little bird or a small mammal, they're very delicate. Turtles are... They're resilient, they're long-lived, they're generally docile, so they're safe to handle. They're not a threat to anyone, little kids or students. And they're pretty smart. They do react to people and situations, and they have different personalities, they absolutely... One Eastern box turtle is not just like cookie cut the next one. So, I think those are some of the ingredients that go into the turtle love pie.
0:32:35.9 DD: Well, many parents who may be listening became the de facto caretakers of the classroom tortoise one summer, named Fiona, and I was a total convert and I loved... I always liked turtles and tortoises, but this one... And I totally agree, she had a total personality, she was wonderfully calm about things, and we took her for walks outside. We would go out in the patio and let her run around, put her... She'd run around the grass, and she was really a great, great turtle. So, moving... But I think I have a misperception here, which is, I think most of us don't think of turtles other than maybe sea turtles and the Galapagos tortoises that you've worked with as endangered, but is that actually true? And what are some of the threats facing turtles and tortoises, aside from sea turtles, but our land guys.
0:33:38.3 DL: Yeah, yeah, it's an interesting perception, and actually, Galapagos tortoises, most of them, there are... Depends on who you're talking to, but they've been divided up into about 10 living species now. Galapagos tortoises and sea turtles are actually much safer in terms of not going extinct than probably 50 other species of turtles. Sea turtles, partly because they're marine and it's really hard... It's easy for numbers to drop dramatically, but it's really hard... Like marine animals in general, whales have been hunted a lot, but marine animals in general... The ocean's so vast and sea turtles don't have a very defined range, so it would be hard to kill all of the sea turtles, even of the most endangered species. Most of the risk to them is when they're on the beach and nesting in habitat.
0:34:44.4 DL: The Galapagos tortoises are well protected. There are about 320 species of turtles in the world, turtles and tortoises. It's not a lot. If you compare that, there are about 100 times as many fish species, about 30,000, and there's probably 10,000 lizards and snakes. So, the turtles are a smaller group than other reptiles. Probably half of those are threatened or endangered, believe it or not.
0:35:21.5 DL: And let's look at the bog turtle, so the North American bog turtle, B-O-G. It's the smallest turtle in North America, it's also the only turtle that's not a sea turtle that's federally protected. And we think there are only about 5,000 of them, and they occur mostly in Appalachia, they do occur from Georgia to Connecticut, even in New Jersey. So, they're vulnerable because they have a very defined range and their habitat has been fragmented, these bog habitats, mostly because of agriculture and housing. And they're extremely valuable to poachers, and so the main threats to non-sea turtles are habitat loss and harvesting or hunting, either for food, especially in parts of Asia, or for the pet trade. In fact, in 1996, we started our... We call it the "Turtle Rescue Team," we might talk about that later, and we treated over 7000 wild injured and ill turtles.
0:36:37.1 DL: But another really cool thing we do is we assist some undercover work with the US Fish and Wildlife Service, and we helped catch some poachers just this year after a five-year sting operation. And not that we were like cloak and dagger, running around in the field, but what we were doing was housing turtles, identifying turtles, micro-chipping turtles as evidence and assisting the government. And to give you some idea, this one guy had poached and sold over 800 Eastern box turtles as pets to Asia. We think about people here bringing in turtles from other places, but our turtles, like some of the freshwater turtles and box turtles, are valued in other countries as pets.
0:37:31.3 DD: Oh, that's interesting. So, we'll talk about that a little bit more. I was going to ask you about your research, but maybe talk about some of the stuff... Not just your research, but what kind of things you engage in. That's interesting.
0:37:49.0 DL: Yeah, yeah. So, with fresh water turtles and box turtles here at NC State. Yeah, so I came here 30 years ago as aquatic animal medicine, as you mentioned, and mostly because I had a lot of experience with fish, ornamental fish, but I always love turtles, and 30 years ago, I remember 1993, I saw 10 turtles that the public would just show up at the vet school, hey, I have found this turtle on the road, it got hit by a car, it's bleeding. And those animals, they're not owned, so they don't come in with an owner, and they're not research animals per se, so they sort of fit in this un-owned wildlife area, and I started treating them, triaging them, and I'd get students to help me and try to scrounge around for supplies and equipment, and I started stacking them up in my research lab, and then the next year we saw about 30 of these, and I partnered up with a local rehabilitator, and so she would... I would treat the turtles, she would take them and rehab them, and then when people call the vet school, we forward the calls to her.
0:39:10.2 DL: Then this continued to grow over a few years, and in 1996, her family was moving to Georgia, and she wanted to see our efforts continue and she had inherited some money from her dad, and we started the turtle rescue team in 1996, and this is an effort run by students, I'm the faculty advisor, but it's a great thing for them to have ownership in clinical cases before their fourth year, and turtles are perfect for this there, as I said, they're resilient. They don't make any noise. They're stackable, they're kind of portable.
0:40:00.1 DL: They don't need to eat every day. I'm not saying you neglect them, but they're less maintenance than a mammal or bird, and we've generated quite a bit of... I think the value of this turtle team is the education component that the students experience, and then the new knowledge, the scholarly work we're able to generate from this huge case load with a citizen science component, and then outreach and education, and then I usually list it last, it's important, but we're not making or breaking any of these species we see with releasing... We probably end up releasing about 250 turtles a year, but I think there's a ripple effect, and then of course, we get involved in things like this, helping the government try to track down the poaching operations.
0:41:03.2 DD: I didn't think of poaching and animals going the other way, because I think we hear a lot, as you said, about the ornamental pet trade here and animals coming into the country, that may not be the... Bringing animals in is a problem, but I guess it probably is a problem taking Eastern box turtles into areas where they are not native, is that correct?
0:41:28.5 DL: That's it. So, a box turtle, I don't know... I don't know how the whole chain works, but... So, the poacher guy, he would sell a box turtle to China or Vietnam for $5000, one.
0:41:45.8 DD: Wow.
0:41:47.9 DL: And a spotted turtle, this is a small aquatic turtle in Eastern US, that was $10,000.
0:41:54.3 DD: Wow.
0:41:54.8 DL: And he was selling hundreds of these, I think they figured out he grossed about $1.5 million dollars on what... Every kid knows a box turtle and you see them crossing the road, and these animals can live 100 years and they don't produce a lot of offspring, a box turtle, a female box turtle lays two to seven eggs, probably most of them are predated or the hatchlings are predated. So, it makes a big impact when people, especially when they remove adults and adult female turtles out of the population, and it's probably more of a problem for box turtles and bog turtles, which are not fully aquatic than fully aquatic turtles, it's a little harder to get to them.
0:42:50.5 DD: Yeah, that's amazing. Let's talk about some of your research, so what research projects... The Foundation's funded a few, I know fairly recently, some student... Veterinary students, scholars through that program, but... You don't have to limit it to just that. Tell me about what research you're doing there at NC State.
0:43:12.6 DL: Yeah, well, let me start with the two most recent Morris funded projects because they're really interested, one's already published, and Amy Reder, she's a fourth-year student now, but she published a paper this year looking at corticosterone levels and stress and linking that and some other parameters like packed cell volume and lactate... Lactic acid, blood levels to survival.
0:43:46.9 DL: because that's one of the biggest challenges we have, is where to put our time and resources, a turtle comes in, I've seen turtles with a severed spinal cord recover to use of their hind legs. We've had turtles missing an eye, missing two eyes, missing two legs, having their stomach hanging out of their shell, all survive. Then we have other turtles that they look pretty good, they have a cracked shell, but otherwise they look okay, and they die the next day. And so, it's really challenging to be able to triage a turtle.
0:44:27.7 DL: Actually, one of the most shoot from the hip ways is how they look when they come in, how they're... Are they... Are they moving around and just trying to go, even though they have this severe injury or are they very depressed and quiet, a lot of times that will give you some indication, but Amy's work looked at corticosterone in box turtles and she found some interesting things, one thing she found is that turtles, if we keep them here in the hospital, they tend to run a higher stress steroid level, than if we move them out of the hospital, I guess that's not surprising when you think about it.
0:45:11.5 DL: Even though we do our best, it's not ideal, there's noise, there's lots of other turtles, there's a lot of light stimulation, we have dogs barking nearby, but we do have our own dedicated turtle clinic area, but when they go out to a rehabber they go out for a walk, like you were talking about walking that tortoise, they get a lot... They can have a lot more individual attention. And she also found that if their corticosterone levels spiked within the first 24 hours, their chances of dying were greater than if the corticosterone level stayed the same or dropped.
0:45:56.5 DL: Her study was really interesting. And as I said, it was published this year. The other issue, and I didn't talk about this, but it ties into threats to native species, and that is invasive species or introduced species. So, you probably heard of the red-eared slider. And I know we're about the same vintage, so back when we were kids, you could go to the Woolworths and buy these little green turtles and the little plastic habitat with the palm tree, and most of those turtles didn't make it, a few did occasionally see these 50-year-old, 60-year-old turtles that people have, but some people still sell these turtles or give them away at surf shops and there are...
0:46:50.0 DL: Without getting into the details, there are regulations on these turtles, because a lot of kids from our generation got sick with salmonellosis putting these turtles or our fingers into our mouths. The red-eared slider turtle is the most invasive reptile in the world, so they've been sent all over the world mostly for food and as pets from the Mississippi River drainage area, they're native to Missouri and Louisiana and places like that. And I've seen these turtles in Asia, I've seen them in Europe, I've seen them in South America in ponds and fountain areas in parks.
0:47:29.7 DL: Well, here in North Carolina, they're not native, but people release them all the time, it's the same thing people let goldfish go and they let... Fill in the blank, snakes go... Look what's going on in Florida. Well... This research that Morris funded, we are looking at the impact of red-eared sliders on the native yellow belly slider, they're in the same genus, and we know they hybridize, and so we wanted... But it's not like some invasive species like let's say a cat in the Galapagos, a cat is an apex predator that will basically kill and eat anything it can catch, red-eared sliders, they're not going to eat other turtles or injure other turtles, but we're wondering, do they outcome... Do they compete for resources with the native turtles, and what does this hybridization do to the gene pool.
0:48:29.3 DL: And so, this research is really neat, we haven't published it yet, but we've learned some things, it looks like in ponds where red-eared sliders, cohabitate with yellow belly sliders. It doesn't look like those yellow belly sliders are any less healthy than the ones without red-eared sliders. So, it's not as if the yellow belly sliders where there are red-eared sliders are skinny or small, they seem okay. And we learned something else, we didn't know if the hybrids were sterile or not, and so we actually answered that question because we had some eggs hatch from a known hybrid, and that proved that the hybrids are sexually viable. So probably not a good thing.
0:49:24.0 DL: The other thing we've done related to this project, and it's so is a feral cat. It's not like they're this alien invader. Humans put them there. And so, there are some people that think, well, we need to catch the red-eared sliders and kill them. I'm more middle of the road. So, what we've been doing is catching red-eared sliders and then sterilizing them, having our students do the surgery, giving them this great experience micro-chipping them and then releasing them again, although now there's some permitting issues that have changed and we're going to have to re-evaluate that for 2023.
0:50:14.1 DL: So those are two of the recent projects that Morris has funded, there are other research areas, we usually try to answer questions and solve problems, so we've done some pharmacokinetics with antibiotics and pain medicine, we've published some research on anesthesia, on surgical techniques, shell repair. We just had a paper published, we noticed trends, after it rains, we see more turtles and the team, the students have to get prepared, and we actually took... This is sort of like a little soft sign, so it wasn't as easy to get published, but we did find that within 24 hours after it rains, our caseload about doubles. And so, we also looked at climate change, and we have 27 years of data, and so we know that 2021 versus 1997, 1998 turtles are emerging about a day earlier a year from hibernation based on when we see turtles presenting.
0:51:36.4 DL: So, we saw that happen. And then we have another really cool project looking at GIS, global information geography data and where turtles come from, and I have a student... She's a third-year student right now, she's identifying turtle hotspots, risk spots where there are certain intersections where we see a lot of patients come in, and maybe it's a dream, but maybe the idea would be to put a wildlife fence or a tunnel. They've done this in Florida under the road where there's a lot of turtle and maybe other wildlife traffic.
0:52:16.6 DD: That would be... That would be really... That would be really cool. Yeah, if we look in the Diehl closet of skeletons, I was one of those kids who had red-eared sliders when I was two and three years old, so pretty little, and my parents did a fantastic job of keeping them alive until... But they were probably... They're still pretty small, so they're still juveniles until we moved from our apartment to a house where I basically grew up in, and during the move, the movers knocked their tank over.
0:52:57.0 DL: Oh, no.
0:52:57.8 DD: And they disappeared, and I was heart-broken, my parents were upset that the turtles were gone, so we may have contributed to losing some red-eared sliders into the wilds of New Jersey when I was a kid, because obviously, we didn't find them by the time my parents realized the movers had knocked the tank over, there was just a big puddle of water and no turtle left.
0:53:25.7 DL: Oh, boy.
0:53:26.2 DD: But yeah, I remember those days and I never thought of them as being a particularly invasive species. So, thanks for kind of getting me up to speed on that. What are some of the big questions and big problems you alluded to poaching, but what are some of the other things that are threatening our freshwater turtles and tortoises in the United States?
0:53:48.9 DL: Yeah, I think that probably based on what we see and the literature, it's probably human development, both in terms of removing viable habitat fragmenting habitats, these turtles... Tortoises and box turtles have pretty limited home ranges, females especially, the males tend to wander more. A female turtle may spend... A female box turtle may spend its whole life in, I don't know, two acres of habitat, maybe less... And we know that male box turtles will wander maybe up to... Up to a mile. So, I think roads are a big... And vehicular traffic, vehicular trauma is probably, that's one of the biggest threats.
0:54:53.0 DL: Also, predation by dogs is a big problem, some dogs are just fine with a turtle, they think it's a rock with legs, and some dogs think it's a living chew toy, a chew toy that's tasty, and so that's our number two presentation for trauma, after vehicular trauma, is chewed by dogs or chewed by some predator. Turtles are pretty... I think that pollution and toxins and things like that, while they're more of a threat to aquatic invertebrates and fishes, turtles breath air, and they have a pretty impermeable integument, so those kinds of issues aren't as important to them. Or much of a threat to them as say water quality or pollution or changing pH and things like that, so I'd say it's mainly loss of habitat and change in habitat.
0:55:58.5 DD: And just so I know, we're talking about turtles and tortoises, but what would happen, what's the impact on an ecosystem if turtles and tortoises disappear?
0:56:11.8 DL: Yeah, and there's one other thing I should probably bring up is infectious diseases, and these can be compounded by stress and climate change and moving animals around, that's what... Humans have been doing that forever, but there's an emerging fungal disease of fresh water turtles and box turtles that was really only identified about four years ago, and people have for decades have been noticing these kind of interesting shell lesions that don't seem to impact the turtle clinically it's more aesthetically, but really, a lot of work done in the University of Illinois actually is kind of identified this fungus now and then there's a viral disease ranavirus that can be pretty serious and can decimate some populations, but I think that... What was your other question? Sorry.
0:57:18.8 DD: It was about what happens if they disappear, because I think...
0:57:21.6 DL: Oh yeah.
0:57:22.5 DD: Yeah. I don't know what niche they occupy per se. And so, what do they do for us? And why would it be dire if they disappeared?
0:57:30.9 DL: Yeah, yeah, that's a great question. Well, we've... So really one of the things they do that's really important is seed dispersal, so turtles, especially tortoises and box turtles are... Well, tortoises are herbivorous, if they stumble upon a piece of meat, they will eat it, but they mostly eat plant matter, fruits, some vegetables, and they're really important in dispersing seeds, you see that in the Galapagos. I'll give you an example. There's an island called Pinta Island in the northern part of the Archipelago. And a lot of people have heard of this tortoise named Lonesome George, he was the last of his species. He died in 2012, he died 10 years ago, and he was probably alone on that island for 50 or 60 years, the last of his species.
0:58:35.0 DL: And there were a lot of goats on that island as... It was a big problem, talk about a place where invasive species are a problem at islands in particular, and the Galapagos wasn't spared, especially goats and cats, dogs to some degree, but... So, all the flora adjoining Pinta had changed over a couple hundred years because there weren't tortoises to do the normal dispersal of the native plants and consume the native plants, and the goats were changing everything with their dietary preferences, so the Galapagos National Park removed all the goats.
0:59:17.4 DL: But then there were no tortoises because Lonesome George was the last one, and they took him in the mid-1970s to the research center in one of the islands to see if they could breed him with females of related species. That never worked out. So, what they did is they had a bunch of tortoises, I think, that were hybrids, except they didn't know what island they came from, because in the old days, the old days being the 1700s and 1800s, mostly whalers were moving tortoises all around and because they were consuming them.
0:59:51.8 DL: And so, some colleagues, some zoo veterinarians actually from the US, went down and sterilized 30 or 40 tortoises, and then they... because they didn't want them to breed because the genetics weren't true, but then they put them on that island to re-establish the normal flora there by eating the plants they should eat and dispersing the seeds. I think turtles also, like box turtles and fresh water turtles, they probably help keep the predator-prey balance strong, turtles, snapping turtles will take fish and invertebrates and things like that, and we see this time and time again, when one species is removed, like when wolves were gone then you get in an explosion of prey animals, and I think the same could be said for habitats where there are turtles, well, maybe the slug population will go crazy and then the slugs will eat a lot of the native plants, and I think any species is just part of the whole puzzle.
1:01:15.0 DD: Well, that's helpful. So, they act a little bit like birds then in the seed dispersal?
1:01:18.5 DL: Yeah, a lot...
1:01:19.3 DD: I never thought about them being seed dispersals, so that... That's helpful to know. So, we need to wrap up a bit, but what is your take-home message for our listeners?
1:01:33.1 DL: Yeah, so the take-home message. The good thing is most people like turtles, and they may not love them, and they may not have bumper stickers and stuffed animals, but most people... I'd love to do a show on snake sometimes, I love snakes, but I know that's not everybody's bag, but most people aren't afraid of turtles, they may be a little tentative around a snapping turtle, so I don't think we have to sell turtles, but I think we have to sell the importance of preserving them, and I think number one is education, learn about what turtles are in your area and what threats they may be up against. It's really important... Two things, don't take turtles out of the wild, unless it's just to show your kids and maybe educate them a little bit, I'm okay with that, but you don't want to basically abduct them from the wild, and then now they're out of the gene pool. And that turtle that maybe is 50 or 60 years old is just gone, and also don't release animals that aren't native. So, releasing red-eared sliders or a tortoise that's not... We don't have any native tortoises here in North Carolina.
1:03:07.9 DL: So those are two things. I guess the other thing is, you can... There's a group called the Turtle Survival Alliance or TSA, and other groups that really act to preserve turtles and tortoises around the world. There's a tortoise in Madagascar called the radiated tortoise. And if you know Madagascar, a lot of things are endangered there and it's an island, it's a big island, it's one of the biggest islands in the world, but still there are a lot of threats to the native species there, and there was a poaching ring, someone found 10,000, 8,000 or 10000 radiated tortoises in one house. It's a huge number, and it was all for the illegal pet trade, and veterinarians were sent from around the world including the US to go and help triage these animals and treat them. So, I would say educate yourself on turtles and the threats to them around the world, again, there's only about 320 species, and when it comes time to charity, it would be great to donate to some of these groups.
1:04:19.8 DD: That's awesome, well, thanks so much. That does it for another episode, so this was a big episode with the dueling turtles group. And so once again, thanks to Doctor Justin Perrault and Greg Lewbart for joining us and we'll be back with another episode next month that we hope you'll find just as informative, because we know the science of animal health is ever-changing and we need cutting edge research information, whether we're treating patients as veterinary caregivers or as pet parents, and that's why we're here. You can find us on iTunes, Spotify, Google podcast and Stitcher. And of course, if you like today's episode, we shall you appreciate, if you could take a moment to rate us because that will help others find our podcast.
1:05:02.4 DD: To learn more about Morris Animal Foundation's work, go to morrisanimalfoundation.org. I know that's a mouthful. And there you'll see just how we bridge science and resources to advance the health of animals, you can follow us on Facebook, Twitter, sort of, because we're off Twitter right now, but we may go back on and Instagram and I'm Dr. Kelly Diehl. We'll talk soon.
0:57:18.8 DD: It was about what happens if they disappear, because I think...
0:57:21.6 DL: Oh yeah.
0:57:22.5 DD: Yeah. I don't know what niche they occupy per se. And so, what do they do for us? And why would it be dire if they disappeared?
0:57:30.9 DL: Yeah, yeah, that's a great question. Well, we've... So really one of the things they do that's really important is seed dispersal, so turtles, especially tortoises and box turtles are... Well, tortoises are herbivorous, if they stumble upon a piece of meat, they will eat it, but they mostly eat plant matter, fruits, some vegetables, and they're really important in dispersing seeds, you see that in the Galapagos. I'll give you an example. There's an island called Pinta Island in the northern part of the Archipelago. And a lot of people have heard of this tortoise named Lonesome George, he was the last of his species. He died in 2012, he died 10 years ago, and he was probably alone on that island for 50 or 60 years, the last of his species.
0:58:35.0 DL: And there were a lot of goats on that island as... It was a big problem, talk about a place where invasive species are a problem at islands in particular, and the Galapagos wasn't spared, especially goats and cats, dogs to some degree, but... So, all the flora adjoining Pinta had changed over a couple hundred years because there weren't tortoises to do the normal dispersal of the native plants and consume the native plants, and the goats were changing everything with their dietary preferences, so the Galapagos National Park removed all the goats.
0:59:17.4 DL: But then there were no tortoises because Lonesome George was the last one, and they took him in the mid-1970s to the research center in one of the islands to see if they could breed him with females of related species. That never worked out. So, what they did is they had a bunch of tortoises, I think, that were hybrids, except they didn't know what island they came from, because in the old days, the old days being the 1700s and 1800s, mostly whalers were moving tortoises all around and because they were consuming them.
0:59:51.8 DL: And so, some colleagues, some zoo veterinarians actually from the US, went down and sterilized 30 or 40 tortoises, and then they... because they didn't want them to breed because the genetics weren't true, but then they put them on that island to re-establish the normal flora there by eating the plants they should eat and dispersing the seeds. I think turtles also, like box turtles and fresh water turtles, they probably help keep the predator-prey balance strong, turtles, snapping turtles will take fish and invertebrates and things like that, and we see this time and time again, when one species is removed, like when wolves were gone then you get in an explosion of prey animals, and I think the same could be said for habitats where there are turtles, well, maybe the slug population will go crazy and then the slugs will eat a lot of the native plants, and I think any species is just part of the whole puzzle.
1:01:15.0 DD: Well, that's helpful. So, they act a little bit like birds then in the seed dispersal?
1:01:18.5 DL: Yeah, a lot...
1:01:19.3 DD: I never thought about them being seed dispersals, so that... That's helpful to know. So, we need to wrap up a bit, but what is your take-home message for our listeners?
1:01:33.1 DL: Yeah, so the take-home message. The good thing is most people like turtles, and they may not love them, and they may not have bumper stickers and stuffed animals, but most people... I'd love to do a show on snake sometimes, I love snakes, but I know that's not everybody's bag, but most people aren't afraid of turtles, they may be a little tentative around a snapping turtle, so I don't think we have to sell turtles, but I think we have to sell the importance of preserving them, and I think number one is education, learn about what turtles are in your area and what threats they may be up against. It's really important... Two things, don't take turtles out of the wild, unless it's just to show your kids and maybe educate them a little bit, I'm okay with that, but you don't want to basically abduct them from the wild, and then now they're out of the gene pool. And that turtle that maybe is 50 or 60 years old is just gone, and also don't release animals that aren't native. So, releasing red-eared sliders or a tortoise that's not... We don't have any native tortoises here in North Carolina.
1:03:07.9 DL: So those are two things. I guess the other thing is, you can... There's a group called the Turtle Survival Alliance or TSA, and other groups that really act to preserve turtles and tortoises around the world. There's a tortoise in Madagascar called the radiated tortoise. And if you know Madagascar, a lot of things are endangered there and it's an island, it's a big island, it's one of the biggest islands in the world, but still there are a lot of threats to the native species there, and there was a poaching ring, someone found 10,000, 8,000 or 10000 radiated tortoises in one house. It's a huge number, and it was all for the illegal pet trade, and veterinarians were sent from around the world including the US to go and help triage these animals and treat them. So, I would say educate yourself on turtles and the threats to them around the world, again, there's only about 320 species, and when it comes time to charity, it would be great to donate to some of these groups.
1:04:19.8 DD: That's awesome, well, thanks so much. That does it for another episode, so this was a big episode with the dueling turtles group. And so once again, thanks to Doctor Justin Perrault and Greg Lewbart for joining us and we'll be back with another episode next month that we hope you'll find just as informative, because we know the science of animal health is ever-changing and we need cutting edge research information, whether we're treating patients as veterinary caregivers or as pet parents, and that's why we're here. You can find us on iTunes, Spotify, Google podcast and Stitcher. And of course, if you like today's episode, we shall you appreciate, if you could take a moment to rate us because that will help others find our podcast.
1:05:02.4 DD: To learn more about Morris Animal Foundation's work, go to morrisanimalfoundation.org. I know that's a mouthful. And there you'll see just how we bridge science and resources to advance the health of animals, you can follow us on Facebook, Twitter, sort of, because we're off Twitter right now, but we may go back on and Instagram and I'm Dr. Kelly Diehl. We'll talk soon.
