Grevy's Zebra: A Star in Stripes

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Speaker 1: Hi, I'm abeny Mone and I'm Rick Schwartz. Welcome to Amazing Wildlife, where we explore unique stories of wildlife from around the world and uncover fascinating animal facts. This podcast is a production of I Heart Radio and San Diego Zoo Wildlife Alliance, in international nonprofit conservation organization behind the San Diego Zoo and Safari Park. This next species is an example of why you should never judge a horse by its stripes. The grebby zebra may look like the zebras most people are familiar with, which is the plain zebra, but the grebby zebra may be more closely related to the wild ass than the horse. Rick. How is it that two different subspecies of the same animal can have a different lineage? Oh wow, Ebony starting to ride off with a deep dive into taxonomy lessons. Okay, so I'll see if I can explain this. Yeah, I appreciate it. No, it's important because it is kind of interesting. I'll do my best to explain it without taking up the entire episode. Here we go. When it comes to the evolutionary lineage of the zebra, fossil records show us that each species of zebra split within the genus equis, or the equines the horses and wild asses of today. But they've done this at different times across these thousands of years. So because of this, it was originally thought that planes zebra was more closely related to the horse, while the Grevy's zebra was considered more closely related to the wild ass. Now fast forward to today, science and technology allows us to look at these species with more detail. With that detail, we gain a better understanding of how these species are related. And at this time, with the information we have, we understand that zebras and wild asses diverged from the same ancestral line shared with the genus equals. Basically, what it all means is that all three species of zebra, the grevy zebra, the plains zebra, and mountain zebra are all more closely related to the wild asses than the horses. Wow. So moving on to possibly an easier question, how did the Grevy's zebra get its name? That is a curious name? Is an ebony? I mean, the other two species, plains zebra and mountain zebra, both have descriptive names. It seemed to just let us know the kind of habitat they reside in, and then you have the grevy zebra. Well, for the grevy zebra, the name comes from Jules Grevy, who was the President of France when French naturalist Emil Estila first described the unique species of zebra in eighty two. It's believed that he did this to honor the president and his interest in animals. That seems to be the reoccurring theme that a species is named after someone or describe where it's found in. Speaking of where an animal is found, grevy zebras have undergone I understand a substantial reduction in range. Where are they currently found? Oh, yes, ebony. They really have experienced a reduction of their natural range. Now, currently grevy zebras are only found in parts of Kenya and Ethiopia, but at one time they also inhabited Somalia and South Sudan. Now they do prefer arid habitats and they've adapted well to areas with less water. They also feed on coarser grasses that other species can't thrive on. So if we were able to stand the plain zebra, which many of us are familiar with, next to the grevy zebra, what differences might stand out? Good question? I think right away of any that I think people would notice the size difference, you know, pound for pound and inch for inche the Grevy zebra are larger. They win around seven seventy to almost nine pounds and measure just over four to five feet in height at the shoulders. And when it comes to the stripes, there's a notable difference there too. In fact, I think that's the easiest way to tell them apart. The Grevy's zebra stripes are narrow in comparison and do not go all the way around their belly, whereas the Plains zebra have broader stripes with shadow stripes or a lighter colored stripe in between the black stripes, and many of their stripes do connect under the belly. Oh and one other noticeable distinction is their nose. Plain zebras have a black nose with stripes connecting to it, but the Grevy's zebra has a nose that is some more of a dark brown than black, honestly, and the stripes usually do not connect to it. Not to check that out, I have to check for the nose. Yeah, the nose nose, so rick The differences are not just found in their appearance, how else, is the gravy zebra different? Oh? I think honestly, the most notable as far as difference would be some of their herd dynamics, or in the case of the grevy zebra, the lack thereof. What I mean by that is, I think we are accustomed to seeing video footage of this great migration in Africa. You know, we see these large herds of zebra with the wilderbeasts and other animals making this giant move across the plains. And for the plains zebra, well, that is exactly how they live in these large herds, mostly made up of females and their offspring, with the dominant male protecting the herd. But when it comes to the grevy zebra, it's different and that they don't have like a major migration and they don't live in these large herds. In fact, dominant males tend to establish a territorial range and the females will wander through these ranges, preferring areas with the most abundant food water. They will spend time together, so it's not uncommon to see multiple Grevy's zebras in the same area, and you can even find bachelor groups of grevy zebras. These are the males who have yet to establish a territory or lost a territory to a more dominant male. So again you might see groupings of Grevy's, but it's nothing like you see in the formal herd dynamics of the plains. Zebra and ric wild horses are known for being fast, more so than wild donkeys. Where do Grevy's zebra fall in this category since they're related to both animals. Oh, they're pretty fast e any, I mean, not quite as fast as a horse. I think it's fair to see horses average miles an hour, but still pretty fast. The grevy zebra, like other zebras, do have some pretty quick and powerful predators that they need to outrun to survive. That said, most zebra species reach a top speed of about forty miles an hour, and although that may not be as fast as a lion sprint, which can sometimes top out about fifty miles an hour, the lion cannot sustain their sprint for very long, but the zebra has much better endurance. So as long as the zebra can stay ahead for a short time, it can definitely outrun, at least outlast a sprinting predator good for the grabby zebra. So there's an estimated two thousand mature grevy zebras in nature. That's less than half of what the population was in the nineteen eighties. Rick, what are some of the factors that have led to this decline? Well, you know, Albany, Honestly, it's similar to other species that we've talked about this time that grevy zebra has faced a few different challenges over the last several decades, from illegal hunting and habitat loss to even population fragmentation, droughts, just a lot of stuff to deal with. But it is worth mentioning that their current population has proven to be stable, meaning the numbers aren't declining, and that's a great sign that conservation efforts are working for the grevy zebra. Now, of course, it doesn't mean that they aren't still an endangered species. It just means that the work that has been done so far over the last several years is working and we need to keep up with those conservation efforts. So moving on, what's the connection between the grebby zebra and livestock Because this is another thing that comes as a surprise when it comes to competition from other animals. I'd immediately think of lions maybe praying on the grevy zebra, but I was surprised to learn that cattle have an impact on the grebby zebras survival chances. Can you explain why the zebra is in competition with with livestock? Yeah, I mean, I guess it does seem odd at first ebony, but the habitat that the grebby zebra lives in is shared by pastoral communities or people who raise and care for livestocks such as goats and cattle. Now, as human populations grow, so does the need for resources, and unfortunately, goats and cattle grays on the same food that the grebby zebra does. Yes. Yes, and some diseases like anthrax can be spread by livestock in the surrounding soil. This is a disease that the grevy zebra is very susceptible to, and a disease that carnivores and even humans can get as well. So historically the challenges between humans needs and the use of the land and the zebras needs and their use of land has kind of been odds with each other. And I say historically because there has been a big shift in how the pastoral communities work with the land. I was fortunate enough to spend time in Kenya a few years ago and visited with the Grevy Zebra Trust and a few of the communities in the Sambu region of Kenya. There is a lot of work being done by the communities themselves to clear out invasive plants and to plant the seeds of native grasses back into those native ranges. Now this helps everyone who lives there, the people, the livestock, and the zebra and so many other species. This kind of community conservation is part of the reason why we see the grevy zebra numbers stabilizing and hopefully to increase in the coming years. That's a great example of community conservation that may be making a big difference. It really is ebony, and when it comes to creating successful conservation plans, often the answers are within the communities that live amongst the wildlife. It really does go to show you that we can do so much more when we work together, combining science, passion, and knowledge at all levels. The Great Grebby's Rally is another conservation effort that takes place. It involves counting the population, Rick, can you tell us more about that, the Great Grebby's Rally and why it's so important? Oh yes, I'm so glad you asked about this ebony because it's it really is this amazing sort of coming together of people from all over the world. The Rate Grevy's Rally is exactly what you just said. It's a tally of the grevy zebra population, including number of males and females, along with their locations. But how exactly can you make sure you're counting all of them? And how can you make sure you're not counting one zebra twice? We'll get this. The Great Grevy's Rally is made up of volunteers from all walks of life, from local community members and scientists to conservationists, zookeepers, wildlife care specialist in anyone from the public who wants to volunteer. The volunteers are broken into groups and given designated coordinates to cover. Each group needs to photograph the right side of each Grevy zebra they observe with a GPS enabled camera, so because every zebra has its own unique stripe pattern, the team can confirm if they're seeing the same one or a different one when they look at those photos, and when comparing photos from years in the past, they can also confirm which individuals are staying in what areas versus who might be moving around more. It really is a massive undertaking. But again, with this dedication of many people working together, the impact for conservation of these and endangered zebras is really powerful, And of course the data is so important. It allows us to understand how current conservation efforts are impacting the populations. And when you can keep an eye on the number of males and females and young, you can better project population growth or decline moving forward. Well, it makes me want to volunteer. How cool would it be to take a family trip and take part of the Great Grebby's Rally if you could swing it, especially when you consider the cause and the impact of it all exactly. Coming up, we'll be talking to Mike Langridge, a wildlife care specialists with the San Diego Zoo Wildlife Alliance. But first this now it's time for the San Diego Zoom Minute, an opportunity for you to learn what's new at the Zoo and Safari Park. More than one grey zebra have been born into the San Diego Zoo Safari Park, the San Diego Zoo and San Diego Zoosa Fire Park are wildlife allies committed to ensuring all life thrives. Did you know while plain zebras require habitats with a lot of water and wild asses require nearly none, the grebby zebra lies somewhere in between. The species has been documented going up to five days without taking a sip of water. Joining the conversation now is Mike Language, a wildlife care supervisor with San Diego Zoo wild Life Alliance. Mike, welcome, Thanks for having me so as a wild life care supervisor, tell us a bit about your role. How much do you get to interact and work directly with animals. That's a great question, a little bit dated in that, you know, I get the opportunity to work with animals pretty frequently. It depends on the day. Back before I was a wildlife care supervisor, I was a keeper or a wildlife care specialist and had opportunities pretty much a hundred percent of the time working directly with animals. And now in my role, I'm more responsible for organizing and coordinating the day to day activities where there's over a hundred animals in the area that I oversee, and seventeen dedicated and passionate wildlife care specialists who take care of those animals directly. And really what I'm trying to do is enable them and get them to be successful in what they need to do in order to have our animals thrive. So we've been talking a lot today about the Grebby zebra and comparing it to other zebras. What can you tell us about what makes the Grebby zebra unique. So the first thing that you notice when looking at a grevy zebra is its size. It's just a larger before and in fact it's the largest wild equit And the striping pattern is brilliant, a thin narrow stripe pattern, large ears. They have a really unique social dynamic where they don't form these permanent herd group social structures. They're more loose based. The only bond that happens with the grevy zebra is with the mayor and the full then that's kind of short lived in itself too. But yeah, I mean, I can go on and on about the grevy zebra, but that's just one thing that's popped right into my head. So knowing this about their social structure and their behavioral patterns, how does your team manage the habitat to reflect these needs. Yeah, so we have to do our research and this isn't just specified with grevy zebra. We take great pride and you know, trying to do everything we can for these animals that are under our care. And so the first thing that we tend to try to do is look at the history of that individual. We look at the history of the species and what is it that they need. We again, know that grevy zebra out in the wild or in a very hot climate, and you know they are going to be constantly grazing. In fact, their natural tendencies are to be eating or looking for food roughly six of the day and it gets even more extreme as the weather gets hotter. It's been recorded as up to even eighty percent of the day is used for trying to obtain food. So, you know, we want to try to mimic that because we know that they're going to need to be mentally stimulated. Our staff is offering food items at different times periodically in different methods. So you know, you could easily just throw a flake of hay out on habitats like, oh if that the animal, but that really doesn't do much for it. We're always trying to do things that would elicit natural behaviors and give them purpose and meaning behind what it is that they do. And the grubby zebra, as you mentioned, their endemic to hot, dry regions in Northeast Africa. Why do you and your staff put so much time and effort into it sounds like almost mimic that natural habitat. What's the benefit for the grevy zebra? Well, I mean, they're born with these adaptations and we want them to benefit from those adaptations. It's also we're constantly observing are we doing right by the animal? Are we seeing these behaviors that we know that they can be doing and are capable of doing out in the wild and need to do out in the wild. And you know, you could even argue the fact that there's a potential that animals could go back into the wild, and why not set them up for success? And you know, with the grevy zebra, were a part of an SSP or a plan that is looking to maintain the genetic integrity of the species. There's recommendations that come from the a C. A and they will say that, you know, maybe you have a stallion or a mare that would be better suited to be bred by another animal and another facility, and we want to accommodate the things, and you know, it may not be in the same climate that they're accustomed to. So again, having some of these behaviors already being demonstrated by the animal could potentially set them up for even more success wherever they go to next. And so the San Diego Zoo's role at this point in time is to support the breeding program at the Safari Park or other places by holding females that are not recommended to breed. So just because you're not actively having your animals that you're caring for breed doesn't mean that you're not supporting that program. And you know, we do it again for several different species where we are that holding program. So when they do get called for a breeding recommendation, whether another animal comes here for breeding the existing animals we have, or we prepare for a shipment where the animals are going to get relocated to another program, we're ready to go. And someone might ask, you know, why is it necessary, why is assisted conservation breeding needed? Well, there's A couple of quick answers that come to mind is that you always want to make sure that you have the security blanket, so to speak, if things really go south out in the wild for whatever reason, that you know you've still got genetic diversity. You know, we want to make sure that we do everything possible to prevent extinction. If we don't do it, then who will Grevy zebra are endangered. Most people wouldn't even think that. I've had the impression being given at all. Zebra everywhere. Grevy zebra since have been on a dramatic decline. We're down to roughly zebra in the wild, and you know, if we don't make some type of change to help that species out, then we will lose them. And they do serve a really important niche in that ecosystem. They've been kind of labeled like a pioneer grazer. I like that expression when I read it, that are going out into these planes in the savannah and they're eating vegetation that's not either preferred or easily digestible by other animals. They have this ability being a hindgut fermentor that they can break down food items that other animals can't. But as a result of eating that plant material, it actually promotes those plants to produce new shoots, new grass, blades, new leaves, and those plant materials are actually going to be essential for other species. So if the grabby zebra is not there and not doing what it is that they do, which is eating undesirable or very low quality nutrient foods, then other species are going to suffer. Wow. So what are some of the challenges to survival for the grebby zebra. It's kind of universal with a lot of other species. Habitat degradation, human encroachment, poaching, drought, competition for the resources. It has a lot of things working against it. But the one thing that's really helping the species is the local communities where they're having grevy zebra kind of in their backyard sort of speak. They're buying into the idea that these animals are important for a number of different reasons and that they can work with the species and try to figure out new ways to coexist. Our role tends to be partnering up with some of these conservancies. We've got a long outstanding relationship with the Northern Rangelands Trust and the Grevy Zebra Trust. We've kind of tied ourselves in a little bit with Westgate Community Conservancy. The partnership has been fantastic. We've been able to send out staff to do what's called the Great Grevy's Rally, and that's a census that's being done out in the Northern Kenya area to try to identify the population. But yeah, the staff that's been able to go out there and not only being a part of that, but then coming back with that message and it is sharing what it is that they were a part of is inspiring not only for our guests but our staff. I mean, it just like rejuvenates everybody. It makes us realize that what we're doing is amazing. We're fortunate to be doing what we're doing. We're thankful for the guests that come through our doors and still want to hear what it is that we have been able to experience and we can share information with them and they can share with us, and ultimately we want this San Diego Zoo Wildlife Alliance to grow and this is the way to do it. Awesome, Well, thanks so much. We've been talking to Mike Language, a wildlife care supervisor with San Diego Zoo Wildlife Alliance. Thanks for listening. We hope you learned a lot about the Grebbies zebra and be sure to subscribe and tune into next week's episode and which will bring you the story of another species from Africa with black and white stripes, but it's not related to the zebra. I'm Ebony Money and I'm Rich Schwartz. Thanks for listening. If you would like to find out more about San Diego Zoo Wildlfe Alliance, please visit sdz w a dot org Amazing Wildlife. As a production of I Heart Radio, our producer is Nikia Swinton and our executive producer is Marcy to Peanut. Our audio engineer and editor is Sierra Spring. For more shows from my Heart Radio, check out the I Heart Radio app, Apple podcast, or wherever you listen to your favorite shows.