ZOONOOZ
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SAN DIEGO ZOO GLOBAL
Birth of a Pygmy Hippo Andean Bear Cub Debut Endocrinology Discoveries Pandemic Interrupts Research Revealing Pocket Mouse Genes
SEPTEMBER 2020
September 2020 VOL. XCIII–NO. 5
Features 6
Adventurous Agapito The Zoo’s Andean bear cub is growing in leaps and bounds—and testing and trying everything that comes his way. BY PEGGY SCOTT
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Little Size, Giant Personality Akobi is the first pygmy hippo calf born at the Zoo in 40 years. That makes him extraordinary, and so does his fearlessness. BY KARYL CARMIGNANI
Conservation 14
When Hormones Are Disrupted In efforts to breed endangered species, hormones play a key role. But what happens when other chemicals mimic them and get in the way? BY CHRISTOPHER TUBBS, PH.D. AND RACHEL FELTON, M.S.
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Field Research and a Pandemic Wildlife researchers have to be ready to face myriad challenges. But the COVID-19 pandemic took three giraffe researchers by surprise. BY JENNA STACY-DAWES, RUTH LEKUPANAE, AND SYMON MASIAINE
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Powerful Tools to Help a Little Species What’s in the genes is invaluable information to help save any endangered species, including the Pacific pocket mouse. BY ARYN WILDER, PH.D.
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26 Graphically Speaking 28 San Diego Zoo Kids ON THE COVER:
Andean bear Tremarctos ornatus Photo by Ken Bohn, San Diego Zoo Global Photographer THIS PAGE:
Aloe sp. Photo by Tammy Spratt, San Diego Zoo Global Photographer
By the Numbers
San Diego Zoo Global’s conservation work in northern Kenya takes a comprehensive and multidisciplinary approach to training, enhancing facilities, sharing knowledge and tools, and community engagement, to ensure that wildlife continues to thrive in this important region.
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Solar-powered tracking devices that have been placed on giraffes throughout northern Kenya to determine the space the animals need.
Number of orphaned elephant calves that have been rehabilitated at the Reteti Elephant Sanctuary.
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Animal health diagnostic labs that San Diego Zoo Global works with in the region.
Partner organizations we collaborate with on conservation projects in Kenya.
ZOONOOZ
10 GPS collars to be placed on African leopards in 2020 to help with data collection on diet, disease, behavior, and territory.
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PUBLISHED SINCE 1926
Because of some exciting changes that will be coming for 2021, our calendar issue of the magazine will not be the November 2020 issue this year. Instead, it will be the January 2021 issue. Look for a regular issue in November, and your 2021 calendar in January!
SEPTEMBER 2020 VOL. XCIII–NO. 05 MANAGING EDITOR
KAREN E. WORLEY
ASSOCIATE EDITOR
The Zoological Society of San Diego was founded in October 1916 by Harry M. Wegeforth, M.D., as a private, nonprofit corporation, which does business as San Diego Zoo Global.
COPY EDITOR
The printed ZOONOOZ magazine (ISSN 0044-5282) is published bimonthly, in January, March, May, July, September, and November. Publisher is San Diego Zoo Global, located at 2920 Zoo Drive, San Diego, CA 92103. Periodicals postage paid at San Diego, California, USA, and at additional mailing offices.
ESTON ELLIS DESIGNER
KERRI ABRAMS SAN DIEGO ZOO GLOBAL PHOTOGRAPHERS
KEN BOHN TAMMY SPRATT
SR. IMAGING SPECIALIST
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Copyright© 2020 San Diego Zoo Global. All rights reserved. All column and program titles are trademarks of San Diego Zoo Global. If your mailing address has changed: Please contact the Membership Department; by mail at P.O. Box 120271, San Diego, CA 92112, or by phone at 619-718-3000. For information about becoming a member of San Diego Zoo Global, please visit our website at ZooMember.org for a complete list of membership levels, offers, and benefits. Subscriptions to ZOONOOZ magazine are $25 per year, $65 for 3 years. Foreign, including Canada and Mexico, $30 per year, $81 for 3 years. Contact Membership Department for subscription information.
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PRESIDENT/CEO’S NOTE PAUL A. BARIBAULT
SAN DIEGO ZOO GLOBAL OFFICERS
Working Toward One Health
H
uman health is tied to the health of wildlife, the health of the environment, and the health of the planet. We understand this now as we never have before. The health of one living thing affects others. This concept, called One Health, makes it clear that the welfare of wildlife and the condition of the ecosystems around us are important to our own well-being.
At San Diego Zoo Global, we understand how important the health of ecosystems is to the wildlife that we work with every day. We draw upon our expertise in wildlife care and health to focus conservation science on saving species. We know that it is impossible to successfully protect wildlife without keeping a balance—from the wildlife, to the ecosystems, to human communities. We can all do our part to create a healthy planet. At San Diego Zoo Global, we are preparing to meet the
challenges of tomorrow by refocusing our conservation and communication efforts to drive greater outcomes, in order to support the principles behind this important initiative. We have always been committed to sharing the natural world with our guests, furthering compassion and understanding. We share this knowledge to support better outcomes for wildlife, and to turn guests into supporters of our mission. Today, our role is more important than
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ever, and our message must evolve to meet the future in front of us. We are in this together—and we can all make a difference!
Steven G. Tappan, Chairman Javade Chaudhri, Vice Chairman Linda Lowenstine, DVM, Ph.D., Secretary Ryan Sullivan, Ph.D., Treasurer BOARD OF TRUSTEES
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Berit N. Durler Thompson Fetter Frederick A. Frye, M.D. George L. Gildred Yvonne W. Larsen John M. Thornton A. Eugene Trepte Betty Jo F. Williams GENERAL COUNSEL TO THE BOARD
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Todd Beck Sophie W. Bryan David Crane Berit N. Durler Chris L. Eddy Nikita Kahn Ellison Arthur E. Engel JJ Fetter Susan Guinn Murray Hutchison Lynelle Lynch Susan B. Major Susan F. McCarthy Diane McKernan Joshua A. Pack Maryanne C. Pfister Philip C. Seeger Elizabeth W. Shoemaker Rosa Sinnott Carter Skeath David M. Tehle Kathryn J. Vaughan, Esq. Tony Yousif
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h e mont e r F s d is Ki oo ctober O ! iego Z s D d i n k a l l S a and Calling nd go Zoo e i years a D 1 n 1 a n S e r e onth at th child , when on all m i k s r s a i P m h i Safar ect wit free ad n e n v i o e c c r re s ca n ile younge lt). Kid u d a ife, wh l n d l a i h w t i ting ug h long (w by mee re thro u e t d i a s n f d il rs o their w wonde e n. h t g loratio erin p v x o e c s d i d lay an d oo r p t u o n fu
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Adventurous Agapito An Andean bear cub is revealing some of the secrets of his species BY PEGGY SCOTT | ASSOCIATE EDITOR, SAN DIEGO ZOO GLOBAL PHOTOS BY KEN BOHN | SDZG PHOTOGRAPHER
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n the early morning hours of January 8, 2020, Andean bear Alba gave birth to her first cub—the first of this species born at the Zoo since 1993. The wildlife care specialists working with Alba knew she was expecting, so they were keeping an extra-close eye on her. One of those specialists, Hali O’Connor, says that Alba had been building her nest and paying a lot of attention to her den— like she knew she would need it soon. Alba’s den was fitted with a closedcircuit camera and microphone, so when the care team reviewed overnight footage, they could listen for the sounds of a newborn. During the replay viewing on January 8, they saw Alba cuddling something to her chest and heard little noises. Sure enough—she had a tiny cub! The care team was excited but cautious, as the mortality rate for Andean bear cubs in their first month is high. But as the cub continued to grow under Alba’s care, it was time to celebrate. ALBA’S “BELOVED” CUB
In late April, Alba allowed the care team enough time for a quick exam of the cub, and they discovered that he is male. He was named Agapito, which means “beloved.” Hali says Alba is a great mother and pays close attention to him. “We are overjoyed about the birth of Alba’s first cub,” says Chris Hamlin, wildlife care manager. “Alba is showing all the appropriate behaviors and being very attentive. We are so impressed with how well she is handling motherhood.” At first, Alba was a little bit of a “helicopter mom,” watching the cub’s every move. As he got older, and a little bigger, Alba began letting him wander a bit. Hali says Agapito is an adventurous cub, exploring and putting everything in his mouth, much like a human toddler. He copies his mom, including helping her to gather bedding. He loves water, and is learning about different types of food. He’s still nursing, but the cub has been observed handling whole fish, yams, carrots, and fruits. Like both of his parents, Agapito is particularly fond of jicama and avocado. His most
Opposite page: Even at just a few months of age, an Andean bear’s characteristic fur “spectacles” are visible around the eyes. Above: Firsttime mother Alba exhibited strong maternal instincts from the very beginning. Left: Agapito continues to thrive, becoming bolder and seeking out new experiences every day.
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recently acquired food skill? He has figured out how to shell peanuts, and is doing a fair amount of independent foraging for foods. By six months of age, Auggie, as he is affectionately nicknamed, was conquering Alba’s swing, playing with enrichment items, and exploring his habitat. The care team helps him with his development by adding moving elements to the area, like a hanging horizontal log that wobbles, and a bridge made from fire hose, to encourage the cub to use different muscles and practice his climbing skills. “He’s quite brave,“ Hali says, adding that Alba’s calm demeanor seems to provide moral support. Should something startle him, however, he makes a beeline for the safety of Alba. It’s not very long, though, until he’s ready to try something else.
FAMILY DISCUSSIONS Above: Climbing is one of Agapito’s favorite pastimes, whether that involves manuevering piles of logs on the ground or any of the suspended structures in his habitat.
Hali notes that these bears seem to have a lot to say, and Auggie “talks” by humming, groaning, and cooing loudly. Alba coos back—they seem to have long conversations. The groaning seems to express impatience, Hali says. Auggie seems to use it when he wants to get into the main habitat to explore after enrichment items have been distributed or the habitat has been cleaned. The cub sees his dad, Turbo, through a viewing window. Occasionally Alba brings Agapito to show him to Turbo through the visiting panel, which has openings so the bears can see and smell each other. Alba is still protective, and she “huffs” at Turbo to tell him he needs to mind his manners. She knows the panel keeps them separate, so she allows some visitation. For a particularly stimulating enrichment experience, the care team occasionally swaps bear habitats, allowing Alba and Agapito to hang out in Turbo’s area, and Turbo to explore theirs. Everyone seems to really enjoy the different sights and smells, with considerable sniffing and stomping around. The wildlife care team is grateful to have the opportunity to watch these relationships grow—every day seems to bring a new revelation.
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Agapito learns about different foods by mimicking his mother, Alba. Yams, carrots, and fruits are among the items he might grab first. He has learned to forage for food on his own.
DID YOU KNOW? Andean bears have only 13 pairs of ribs, one pair less than other bears. Rings of white or light fur around their eyes give these bears their other common name—the spectacled bear. An Andean bear’s light markings give the bear its scientific name, Tremarctos ornatus, which means “decorated bear.” The San Diego Zoo’s first Andean bears arrived in 1938, and were named Polly, Toby, and Punch. The largest bear that ever lived was the extinct, giant short-faced bear Arctodus simus, a relative of the Andean bear. Fossils of this bear have been found in California’s La Brea Tar Pits.
GATHERING ANDEAN BEAR SECRETS Each of Agapito’s new experiences isn’t just a milestone for him—it might also provide insight into his species’ existence in South America. As he expands his world, Agapito’s growth is giving researchers who are dedicated to studying Andean bears some muchneeded clues as to the day-to-day life of these bears in their native range. Andean bears (also called spectacled bears) are good at hiding in their habitat in South America, and little is known about mother and cub interaction. “The Andean forests where we work are so rugged and dense that it will be a long time before we can study the maternal behavior of wild bears there,” says Russ Van Horn, Ph.D., scientist, Population Sustainability, San Diego Zoo Global, and co-chair of the International Union for Conservation of Nature’s Andean Bear Expert Team. “Alba’s behavior and her cub’s development will suggest how closely, and for how long, wild bear mothers and cubs may be linked to birth dens, where we think they’re sensitive to disturbance by humans.” Habitat loss, fragmentation, and degradation, as well as poaching, are among the threats Andean bears
face. In southeast Peru, our researchers work primarily in the cloud forest and other humid montane forests, where most Andean bears are thought to live. Together with conservation partners, our Population Sustainability team is documenting Andean bear presence and characterizing critical aspects of bear ecology and behavior, such as foraging, trail use, and marking. Their goals are to determine not only where these bears live, but also how they interact with their environment and the plants in their varied habitats. The team intends to dig deeper to better understand not just what bears eat, but what nutritional benefits they gain from their varied diet. Over time, they’ve realized how little is known about other mammals that also depend on these habitats, so what is being discovered through the fieldwork is being leveraged to benefit the conservation of other mammals in these Andean forests, as well. By observing Alba and Agapito, our experts hope to learn about what goes on between a mother and her cub, and how this information can help conservation efforts in the Andean forests. Agapito is still a little bear—but he’s already helping Andean bears everywhere. SAN DIEGO ZOO GLOBAL / SANDIEGOZOO.ORG / 9
Little Size, Gian The Zoo’s pygmy hippo has made quite a first impression. BY KARYL CARMIGNANI | STAFF WRITER, SAN DIEGO ZOO GLOBAL PHOTOS BY KEN BOHN | SDZG PHOTOGRAPHER
M
abel was made for motherhood. The Zoo’s animal care staff plotted, planned, and problem-solved for months in advance for every birthing outcome imaginable; but the 660-pound pygmy hippo took to caring for her 12-pound calf like a fish to water. Wildlife care experts were relieved the birth went smoothly, and remained cautiously optimistic that the tiny calf would survive. “The calf survival rate in this species is low, and it is not uncommon for first-time moms of many species to have more problems with pregnancy and infant rearing,” explained Deena Brenner, DVM, senior veterinarian, San Diego Zoo.
She and the rest of the team—vets, wildlife care specialists, and neonatal and nutrition experts—are elated that Mabel and the calf have remained strong and healthy. The calf, named Akobi, continues to meet or exceed developmental milestones and bond with his calm and attentive mom. “We couldn’t have asked for a better outcome,” said Dr. Brenner.
WALK ON THE WILD SIDE Pygmy hippos Choeropsis liberiensis are secretive, and little is known about their habits and maternal behavior in their native-range countries. Found in the forests and swamps of West Africa, primarily in Liberia, with small populations dotting Sierra Leone, Guinea, and Ivory Coast, they are notoriously difficult to track and observe. Shy and nocturnal, they generally stick to deep, tunnel-like paths through the underbrush to forage near rivers, streams, and swamps. While they loosely resemble their gigantic relative the river hippo, the pygmy hippopotamus is distinctly different. This pintsized herbivore is much less aquatic than its cousin, and therefore has less webbing between its toes. Its eye placement is also lower on the face,
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nt Personality
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Rolling On. Mabel’s calf is thriving under her watchful eye! The little male, Akobi, mimics his mom’s pygmy hippo behaviors, from enjoying the pool to munching on greens. The two can be observed in their habitat in Lost Forest at the Zoo.
and its legs are a bit longer, relatively speaking. Pygmy hippos are listed as Endangered on the International Union for Conservation of Nature (IUCN) Red List of Threatened Species. Historically, they ranged far and wide across West Africa, but human activities like logging, farming, and increasing human development have led to a significant decline in their populations. Currently, fewer than 2,500 pygmy hippos exist in Africa.
BIG AND BRAVE At the San Diego Zoo, the pygmy hippos share their habitat with acrobatic monkeys: two lesser spot-nosed guenons Cercopithecus petaurista and two Wolf’s guenons C. wolfi, which add significant 12 / ZOONOOZ / SEPTEMBER 2020
flair (and enrichment) to the habitat. Mabel and her calf spent time in their maternity area away from the primates initially, but they are gradually being introduced as the animal care staff monitors the interactions. Male pygmy hippos are not involved in calf rearing, so Akobi’s father, Elgon, does not spend time with Mabel and the calf. Tipping the scales at around 60 pounds as of this writing, the rotund calf is still getting most of his nutrition from nursing, and a small amount from his mom’s food pellets and mouthing her greens. Leanne Klinski, wildlife care specialist, described another interesting behavior: pygmy hippo mothers typically lie down to nurse their calf, but this calf insists on nursing standing up. “He just positions
Getting “Hip.” While pygmy hippos are less aquatic than river hippos, they still spend a fair amount of time in the water. Mabel is ready to rescue and protect her calf as he learns the ropes.
himself underneath her,” and Mabel accommodates him. The dynamic duo is doing great, spending time on the beach and in the pool. Mabel is protective and watchful over her calf. She is always mindful of the little guy, and “nudges him into shallow water when she thinks he’s in over his head,” said Leanne. She said that while pygmy hippos are typically “hiders,” stowing their young in the brush hidden from predators for the first couple of weeks, Mabel’s calf insists on being a “follower,” tagging along wherever she goes. “He’s very brave! He is writing his own story.”
PREPARATIONS FOR A RARE BIRTH Given the rarity of this species in zoos, and its endangered status throughout its range, it’s no wonder months of preparation went into this special birth event. Pygmy hippos reach sexual maturity around 4 years old—Mabel’s age—with a gestation period of 180 to 210 days. Wildlife care staff had been working with Mabel on mock ultrasound training, getting her accustomed to the different sensations and behaviors so her health could be monitored. This prepared her for the real deal later on. It takes baby steps—and positive reinforcement—to elicit the
desired behaviors and keep stress levels low. “We wanted her to feel comfortable with the ultrasound,” said Dr. Brenner. “Happily, she readily participated in ultrasound exams throughout her pregnancy, which allowed us to track the calf’s growth and development. Mabel is the best!” A state-of-the-art, portable ultrasound machine was acquired, which could read through her side and provide detailed images. The pygmy hippo habitat was modified to ensure the safety and well-being of the calf, including additional heaters, misters, and some changes to the maternity pool. Perhaps most helpful was the installation of cameras in the maternal area. “Remote monitoring meant we could closely observe her labor and the birth without disturbing her,” said Dr. Brenner. “This gave us the opportunity to determine whether any medical interventions were needed.” Fortunately, the birth went off without a hitch, and Akobi continues to thrive. Mabel’s maternal instincts are spot on. “It’s amazing to watch Akobi surpass developmental milestones,” Dr. Brenner added. Mabel and Akobi are helping to rewrite the story for their special species. SAN DIEGO ZOO GLOBAL / SANDIEGOZOO.ORG / 13
When Hormones Are Disrupted
Solving endocrinology puzzles to help endangered species
BY CHRISTOPHER TUBBS, PH.D. AND RACHEL FELTON, M.S .
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REPRODUCTIVE SCIENCES, SAN DIEGO ZOO INSTITUTE FOR CONSERVATION RESEARCH
PHOTOS BY KEN BOHN SDZG PHOTOGRAPHER
n the field of endocrinology, measuring hormones can tell us a lot about wildlife. Hormones, in some way or another, are involved in the regulation or control of nearly all biological processes. A single species can produce hundreds, if not thousands, of different hormones, and most of them remain largely unstudied in wildlife species. Hormones do many things. They are critical players in the control of growth and in an organism’s metabolism. In addition, species that begin life in one form and change into another, like a tadpole that changes into a frog, owe this metamorphosis to hormones, which are instrumental in the process. Hormones are essential to reproduction, and males and females produce different types and levels of hormones. What specific hormones do in different species can also vary. For example, in many mammals, the hormone cortisol is released when an animal experiences stress—like a nearby predator—starting a process to generate enough energy to avoid the stressful situation. In fish, cortisol also controls the stress response; but in fish species that migrate between fresh and salt water, cortisol also helps them maintain proper salt and mineral balances in their bodies as they move between these environments. Same hormone, different purpose.
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Left: Christopher Tubbs examines cells treated with EDCs to determine the possible effects. This photo: Kiazi’s first calf, Ellen, was the second to be born after the new diet was implemented. Below: Samples of phytoestrogens isolated from the rhino diet.
THE RIGHT KEY FOR THE LOCK As middle school or high school students, most of us were probably taught something like this: “Hormones are chemical messengers produced in one part of the body, and then travel through the bloodstream to other parts of the body, where they have an effect. Once they arrive, hormones bind to proteins called receptors. This relationship is like a lock and a key. A single type of hormone (the key) can only bind to its specific receptor (the lock). This ensures that particular hormones have very specific functions.” That’s a good overview of a critical aspect of hormone function. Without
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their biological accomplices, the hormone receptors, hormones are not capable of doing much at all. However, as is the often the case in biology, there are exceptions to the rule. In the case of hormone receptors, it turns out some of them can bind to a whole lot more than only their specific hormones, and, as it turns out, that can cause problems. It wasn’t until my sophomore year in college that I learned that there are many chemicals in the environment that can also interact with hormone receptors. When they do, the usually tightly controlled actions of hormones can be disrupted, and the biological consequences can be profound. In the Endocrine Lab of the Reproductive Sciences group at the San Diego Zoo Institute for Conservation Research, we specialize in studying how environmental chemicals interact with hormone receptors and interfere with reproduction in wildlife. By studying hormone receptors and how they interact with environmental chemicals, we are using the knowledge gained to save species.
HORMONE IMPOSTERS Environmental chemicals other than hormones that interact with hormone receptors are called endocrine disrupting chemicals (EDCs). EDCs have been studied for decades,
and research has shown that they can bind to a receptor and prevent it from working properly. They can also activate a receptor when the hormone is not present, kicking into motion physiological processes at inappropriate times. Given all the processes that hormones control, the mixed signals caused by EDCs can be wide-ranging and highly variable in their severity. Our team is interested in the impacts EDCs can have on reproduction in threatened and endangered species. However, studying these types of questions in species for which there are few individuals, and limited sampling opportunities, can be challenging. To circumvent these challenges, we take advantage of the critical role hormone receptors play in EDC function to identify potential EDCs and predict what effects they may have on a particular species. Each of our projects, for the most part, resides in the laboratory. Surrounded by test tubes, cells growing in culture, and pipettors, we isolate the genes that encode the hormone receptors from small tissue samples collected from the species we study. We then place those genes inside cells that make the actual receptor proteins. Once the receptor proteins are made by the cells, we treat them with suspected EDCs and measure the interaction between the two, which gives us a clue about their potential to cause reproductive harm. It may seem far-fetched to think that what we measure in test tubes in the lab can predict how an EDC might affect a complex, living organism.
However, we have successfully employed this approach to study the effects of EDCs on a number of species.
RESULTS FOR RHINOS Our first foray into this approach focused on how natural, plant-produced chemicals called phytoestrogens affect reproduction in white rhinos. Our initial studies showed that phytoestrogens were very good at interacting with white rhino estrogen receptors to mimic the hormone estrogen. We hypothesized that this might explain why female white rhinos that consume high phytoestrogen diets struggle to reproduce—the phytoestrogens were preventing estrogen from working properly in the rhinos’ reproductive cycle. Working with our wildlife care colleagues and nutritionists at the Safari Park, we changed the diet for these animals and provided lower-phytoestrogen plant foods instead. Because a rhino pregnancy lasts for 16 months, it took a while before we could find out if this change would, in fact, make a difference. The anticipation made it even more exciting when the Safari Park had two successful southern white rhino births from females that had previously failed to reproduce: Masamba, born to mother Holly on April 2, Above, left: 2016; and Ellen, born to mother Kiazi on April Genes encoding 30, 2017. And the trend continues—more births steroid receptors from are expected. endangered species are inserted into cells, which This success with our rhino work has then make functional paved the way for us to conduct similar studies receptor proteins. in other species, including California condors, Below, left: Masamba was the first southern looking at chemicals they consume while white rhino calf born feeding on marine mammal carcasses, after the new diet was and big cats, looking at the phytoesgiven to the adults. Below, right: Rachel trogens they accumulate in their Felton prepares to treat system through consuming cells with suspected their prey. There is much endocrine disrupting chemicals (EDCs). yet to discover!
Field Research and a Pandemic Three giraffe researchers share their accounts of working under unusual circumstances BY JENNA STACY-DAWES
POPULATION SUSTAINABILITY, SAN DIEGO ZOO INSTITUTE FOR CONSERVATION RESEARCH
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RUTH LEKUPANAE
TWIGA WALINZI, NAMUNYAK CONSERVANCY
SYMON MASIAINE
TWIGA WALINZI LOISABA, NAMUNYAK CONSERVANCY
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JENNA LOOKS AHEAD TO A PROJECT IN UGANDA
orking alongside the dedicated conservationists of the giraffe research team in Kenya is one of the best parts of my job. I was ecstatic when I found out that Ruth Lekupanae, one of the team members, and I would be traveling to Uganda to assist the Giraffe Conservation Foundation (GCF) with surveys of critically endangered Nubian giraffes—thanks to the continued collaborative partnership between San Diego Zoo Global and GCF, and the generosity of Save Giraffes Now. With a population of only 3,000 individuals left, Nubian giraffes are in desperate need of increased conservation efforts and protection throughout their range, and we were excited to join the effort.
Ruth Lekupanae has been working on the Kenya giraffe conservation program since its inception in 2016, and she is currently the only female member of the Twiga Walinzi, which means “Giraffe Guards” in Swahili. Starting off as a ranger, her dedication to conservation and her passion for wildlife and her community led her to become one of the project’s most important research assistants. To be able to take her on her first plane ride and have her join me in Uganda would be an amazing and unforgettable experience for both of us. I was looking forward to getting started on the surveys at Uganda’s Pian Upe Game Reserve.
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The tall order of giraffe conservation. Projects in several areas study giraffe populations and habitat use.
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RUTH SHARES HER RESEARCH EXPERIENCES
am from Wamba, a town on the western side of the Matthews Mountain Range in Namunyak Community Conservancy. Having grown up in northern Kenya, and having only traveled to Nairobi once before, I was excited for this opportunity. I was most excited to see how other places are protecting their giraffes and wildlife—but also to go on a plane!
Our first stop in Uganda was Pian Upe Game Reserve, to monitor 14 Nubian giraffes that had been moved to the reserve in October 2019 from Murchison Falls National Park. It was shocking to learn that giraffes occurred in this area as late as the 1990s, but had been completely eliminated from the area by over hunting. After a few hours of tracking, we were able to find three of the new giraffe residents. This was my first time seeing another subspecies of giraffe other than reticulated giraffes, and I was surprised to see they did not look all that much different, maybe just a bit lighter in color. It was so nice to see them acting content in their new home. After visiting Pian Upe, the group traveled to Murchison Falls National Park, the former home of the 14 giraffes, where GCF has established a long-term monitoring and conservation program for Nubian giraffes. We saw large herds here, some groups containing 50 individuals. While it was encouraging to see so many giraffes, 20 / ZOONOOZ / SEPTEMBER 2020
it was very sad to see many animals that were impacted by humans, primarily in the form of snare wounds. We have seen snares in Namunyak, but not enough that you can find animals with snare wounds. Just as the Twiga Walinzi team does in Namunyak, we need to work with the communities in this area to tell people that the animals belong here, and it is our responsibility to protect them. We have really focused on working with our communities in Namunyak to reduce the poaching there. I think involving the communities in Uganda for conservation is very important and needed.
CHANGE OF PLANS FOR JENNA AND RUTH Doing conservation fieldwork is always full of unexpected challenges, and you need to be able to adjust plans at the drop of a hat. However, Ruth and I certainly didn’t foresee facing a challenge like a global pandemic. It hit while we were in the middle of our surveys, and our time
in Uganda was cut short due to mounting concerns over COVID-19. We were in a small camp in Pian Upe when the camp manager mentioned the US might be imposing travel restrictions. Worried about getting ourselves home, we scrambled to find Wi-Fi and cell service at the top of a hill. Trying to quickly organize travel for two people back from a remote game reserve amid growing pandemic concerns and closing airports was not something I thought I would ever add to my list of skills! On the day we managed to organize flights out of Entebbe in Uganda, Kenya shut its borders to non-Kenyan citizens, meaning I would have to wave goodbye to Ruth from the customs checkpoint in Nairobi. I had to cross my fingers that my flights would not be cancelled, hope that my allergies would not act up while I was going through customs (sneezing and coughing would not be good!), and hope that I had enough wipes and hand sanitizer to get me home. By the time I arrived back in San Diego, I had taken 2 taxis and 4 planes, and had spent over 24 hours in layovers at various airports alone—but I was home. Ruth got home safely as well. On the one hand, we were both glad; on the other, we did have moments of wondering if it might not have been better to be quarantining in the open savanna with the giraffes!
I
SYMON RECOUNTS HIS CONCERNS FOR CONSERVATION AND COMMUNITIES
PHOTO BY: (TOP, LEFT) PHILIP CARTER
am the conservation coordinator for the Twiga Walinzi team in northern Kenya. Growing up as a pastoralist, I have always had a passion to help in the conservation of wildlife and advocate for the coexistence of wildlife and livestock. The thought of being able to help animals was, and is, a dream of mine. I want to educate people about how we can tackle the threats that animals face. I am aware of the challenges between humans and wildlife, and without conservation, ecosystems can fall apart, causing the loss of both.
The global pandemic has inflicted a new blow to the protection of our natural resources. The threat of COVID-19 has required people who work in wildlife conservation to go home and be with their families, leaving the conservation work behind. Thankfully for our teams, the majority of the COVID-19 cases seem to be restricted to Nairobi, Mombasa, Kwale, and Kilifi—not too close to us at this time. However, to limit the spread of the virus throughout Kenya and in conservationrelated areas, authorities have included the closure of national parks as a social distancing measure—which indirectly puts wild animals, especially elephants and rhinos, at the mercy of poachers, who target them for their tusks or horns. Additionally, closing the national parks has temporarily halted ecotourism, from which the funds needed to protect the parks are derived. Not only does this suspend a major form of revenue for our country, but many of the wildlife guardians are unable to go to work and receive an income as well. As part of its integrated conservation strategy, the Kenya Wildlife Service has involved local people in wildlife protection by providing jobs as trackers and eco-guards in the national parks, but now those jobs are unavailable due to the closures and lack of revenue. People are apprehensive about the spread of the virus into the rural areas. Some pastoralists are worried that the virus might affect their livestock. A primary problem in our communities, besides
the lack of employment, is access to basic commodities in our villages and the limited transportation of goods across the counties, including food staples and, important now, hand sanitizer. Additionally, as most of us continue to keep livestock as a means of income, there is now, as a result of the pandemic, a problem of where to
sell livestock so that we are able to buy the required goods. While we are lucky that a high number of COVID-19 cases have not yet come to northern Kenya, the indirect threats of the virus are worrying. The Twiga Walinzi team has been at home and taking precautions. While we feel good to be with our families, we are deeply saddened that we are not seeing our friends the giraffes. I feel I have giraffes as part of me and I am part of them. Our team is calling officials daily, asking for any information on COVID-19 and the state of the nation, so they can go back and be with giraffes, to study them, understand them, and most importantly, protect them. We really hope that this pandemic comes to an end soon, and people can go back to their normal lives, as we believe the giraffes need to see us—and we also need to see them.
Clockwise, from top left: Ruth and Jenna in the field; Ruth observes a group of giraffes; the Twiga Walinzi head out; Symon with giraffes in the background.
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POWERFUL HELP A LITTLE TOOLS SPECIES Conservation of the endangered Pacific pocket mouse
W
BY ARYN WILDER, PH.D. | CONSERVATION GENETICS, SAN DIEGO ZOO INSTITUTE FOR CONSERVATION RESEARCH PHOTOS BY KEN BOHN | STAFF PHOTOGRAPHER
eighing about the same as three pennies, the Pacific pocket mouse Perognathus longimembris pacificus is the smallest mouse species in North America. They get their name from pouches in their cheeks, used to carry food and nesting materials. In their native habitat, they disperse the seeds of native plants, and their excavation of underground burrows aerates the soil and encourages plant growth.
22 / ZOONOOZ / SEPTEMBER 2020
SMALL SPECIES, BIG CHALLENGE Once found in coastal habitats stretching from Los Angeles to the southern US border, these critically endangered animals now persist in just three small populations in Southern California. These dramatic and dangerous population declines prompted the establishment of a conservation breeding program in 2012 at the San Diego Zoo Institute for Conservation Research, to help save the species from extinction. The remaining populations are isolated from one another by long distances and urban barriers, which prevents beneficial outbreeding and makes inbreeding more likely. In breeding programs aimed at conserving animals from small or isolated populations, scientists must balance the competing needs of adding genetic diversity and avoiding the introduction of harmful genes. This makes for a delicate task of boosting diversity in the endangered Pacific pocket mouse. Through our research, we are using genetic tools to help us better manage the Pacific pocket mouse population, both in the breeding program and throughout their range. Genotyping hundreds of mice at about 20 different sites in each of their genomes sheds light on population differences and genetic diversity, and helped us to better understand how a mouse’s reproductive success was related to its ancestry. But these studies also raised
Top: A prime Pacific pocket mouse habitat includes the right plants for the seeds the mice eat, but also the right type of soil for burrowing. Middle: Cheek pockets let this species quickly stock up on food to take back to the burrow. Bottom: We were able to create “just right” mini habitats at our facility that allowed for protected breeding, which increased the population.
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“This study provides direct data to help us understand how populations will respond to assisted migration.� While we observe and protect re-introduced mice in their native range, we care for and nurture breeding to increase population numbers at our Pacific Pocket Mouse Conservation Breeding Center.
24 / ZOONOOZ / SEPTEMBER 2020
a number of questions that could not be addressed with traditional genetic methods that use only a tiny fraction of the genome.
FROM GENETICS TO GENOMICS
BY THE NUMBERS
20
The number of years the Pacific pocket mouse was considered extinct.
1993
The year they were rediscovered.
6-7
Months spent in winter hibernation.
3
The duration of gestation in weeks.
41
The age in days at which they can reproduce.
What to do when a handful of genetic markers will not do? Sequence the whole genome! We now have entire genome sequences for nearly 400 Pacific pocket mice from the three wild populations and the conservation breeding program. With each genome close to 2.6 billion base pairs in length, the raw data alone requires more storage than the capacity of 20 iPhone 7s combined, a figure that grows several times over during the process of analyzing the data. Moreover, the computational power required just to align the data so that it can be boiled down to a set of informative genetic variants takes two weeks, with the task spread across 30 CPUs. (For reference, most laptops have 2 CPUs.) From these genomes, the first of their kind for a species in the family Heteromyidae, we have identified about 14 million genetic variants across the Pacific pocket mouse genome. We are hopeful that this far more complete and comprehensive dataset will allow us to address long-standing questions. For example, a first analysis of this genomic dataset aims to understand the history of the Pacific pocket mouse. How large are the wild populations, how large have they been historically, and how recently did they decline? How long have the populations been isolated? Are there local adaptations that are unique to the different populations? Understanding their history will provide important information about the source of population declines, and whether enabling migration between the isolated populations is an appropriate management strategy.
WEIGHING THE FUTURE Drawing on genetic data from six generations of Pacific pocket mice in the conservation breeding program, we tracked reproductive success relative to a mouse’s wild ancestral population. Using the num-
ber of offspring as a measure The 700-squarefoot Pocket Mouse of fitness, we examined Conservation the reproductive success Breeding Center is of more than 300 Pacific located in a remote area of the San Diego pocket mice. Zoo Safari Park. Descendants of the smallest and least genetically diverse population had the lowest reproductive success. Interbreeding with the larger, more diverse populations increased the fitness of their offspring relative to this small population, but came at a cost to the larger population. Our findings indicate that genetic diversity should be introduced from the larger, genetically healthier populations of Pacific pocket mice into a smaller, less healthy population—and not the reverse. These results reinforce the idea that when there is a large difference of populations, gene flow should be unidirectional from the more-fit to less-fit population, in order to avoid the introduction of deleterious alleles into healthier groups. This study provides direct data to help us understand how populations will respond to assisted migration. Boosting genetic diversity by introducing genes from outside populations may help prevent inbreeding and increase fitness, to better enable wild populations to be self-sustaining—the ultimate goal in saving species. SAN DIEGO ZOO GLOBAL / SANDIEGOZOO.ORG / 25
G R A P H I C A LLY S P E A K I N G
About Elephants Some animals are so unmistakably unique that they are instantly recognizable. Here we take a closer look at just some of the things that make these mighty mammals so marvelous. BY DONNA PARHAM | STAFF WRITER
ILLUSTRATION BY ALLISON BRITTAIN | STAFF ILLUSTRATOR
About midway between an elephant’s eye and ear lies its temporal gland. The oily secretions of these glands are a form of chemical communication for elephants.
EARS Humans can’t hear them, but an elephant’s low-frequency calls can be heard by other elephants up to five miles away. THICK-SKINNED Have you ever heard an elephant called a pachyderm? The word means “thick skin,” and an elephant's skin can be up to an inch thick on some parts of its body.
MULTIUSE TOOLS An elephant uses its tusks for offense and for defense; for digging for water, salt, and food; for debarking trees; for moving branches; and for lifting heavy objects. INVALUABLE ASSET An elephant’s trunk is for breathing, collecting food and water, and interacting with other elephants. In water, an elephant uses its trunk as a snorkel to breathe.
An elephant’s skin is so sensitive that it can feel a fly landing on it.
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SIZE WISE A newborn calf typically weighs between about 165 and 265 pounds—about the weight of an adult man.
TUSK, TUSK PERMANENT TEETH In African and male Asian elephants, tusks grow in at about 6 to 12 months of age.
A large male African elephant can be three feet taller than a city bus, and as long as a stretch limo. And it can weigh as much as 4.5 average-sized cars.
LEFT OR RIGHT? Elephants favor one tusk over the other, much like we do with our hands.
BABY DATA
The successful elephant breeding program at the San Diego Zoo Safari Park has allowed us to collect detailed data about nursing, behavior, and growth of African elephant calves. Such information is a valuable resource for wildlife care specialists at the Reteti Elephant Sanctuary in Kenya.
FAT TO GROW ON PERCENT FAT CONTENT
DIFFERENCES
20%
5%
HAVE YOU
HERD? AFRICAN
ASIAN
Males and females have tusks
Only males have tusks
Larger ears (2x size of Asian ears)
Smaller ears
Ears shaped somewhat like like Africa
Ears shaped somewhat like India
Generally larger
Generally smaller
Dip in middle of back
Rounded back
An elephant herd consists of related females, called cows, and their offspring. The leader is always a female—the matriarch. Adult males, called bulls, only visit herds for breeding.
BY THE NUMBERS 330 <5 40
Pounds of plants an elephant can eat each day.
Minutes after birth until a newborn calf stands (typically). It is 60 minutes until it walks.
ELEPHANT MILK
HUMAN MILK
➞ African elephant calves at the Safari Park gained an average of about 1.3 pounds per day for the first 75 days of life. ➞ An elephant calf nurses for two to three years.
Hours of sleep an elephant gets per day.
➞ A calf’s first successful nursing bout usually happens within about six hours.
ENDANGERED The estimated population decline of African elephants from 2007 to 2015 is 110,000—mostly due to poaching for their ivory tusks.
WHO NEEDS HANDS?
An elephant manipulates small objects with the sensitive, fingerlike projections at the tip of its trunk. Asian elephants have one “finger,” and African elephants have two.
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Check out our new online video series: Kids Corner!
Each episode takes you on fun and wild adventures to learn about animals and their lifestyles. Visit zoo.sandiegozoo.org/kids-corner.
Heads up One skill a conservation researcher needs is a keen eye for detail. Can you “spot” the 10 differences in the patterns on these two snake heads? S-s-see how many you can find!
Did you know?
In China’s Mang Mountain pit viper, individuals have spot patterns on the top of their heads that are as individually identifiable as our fingerprints.
28 / ZOONOOZ / SEPTEMBER 2020
1. species
2. prey 1 0. m o l t s
When a snake molts (sheds its skin), the old skin breaks down and adds nutrients back to the soil.
9. antarctica Snakes can be found on every continent except Antarctica.
There are about 3,000 snake species. Not everyone likes snakes—but we need them! They play a vital role in their ecosystems.
3. teeth
Some snakes have over 200 teeth. The teeth aren’t used for chewing—instead, they point backward to prevent prey from escaping.
The warmer a snake’s body, the more quickly it can digest its prey.
Look for the 10 snake words on this page in the word search box— remember to look forward, backward, up and down, and diagonally.
a x h l f h s g d m a j
r n d n c e t h f s n l
q i a n i o j e i v t m
w k b c o k a o e n a y
f t e s o a w p h t r p
s p g k r n s f w b c l
s a x y s l d o j p t m
n i n t e r n a l p i c
i p s t l o m r r p c z
s e j v a f b e g c a c
y d a g c z y r n v w q
z a o r s t d w k y v v
4. anaconda Weighing up to 550 pounds, the green anaconda is the heaviest snake in the world. The reticulated python is lighter, but it can grow even longer—up to 30 feet long.
6. jaws
Snakes can’t bite off chunks of their food—they swallow it whole. Good thing they have flexible jaws!
8. internal
Snakes have internal ears but not external ones.
7. r i b s
While you have 24 ribs, some snakes have more than 400.
5. scales
Scales cover every inch of a snake’s body, even its eyes.
SAN DIEGO ZOO GLOBAL / SANDIEGOZOO.ORG / 29
ZOONOOZ
®
SAN DIEGO ZOO GLOBAL
Box 120551, San Diego, CA 92112
OCTOBER IS KIDS FREE MONTH!
GOING
Virtual!
PARTY LIKE N e v e r BEFORE!
The San Diego Zoo’s Food, Wine & Brew Celebration is going virtual! Saturday, September 26, 2020 at 5 p.m. PDT Get your PARTY BOX, browse the Food Hall & Market, and shop our online auction at ZooFoodAndWine.com.