Apes and Monkeys

Apes and Monkeys

34

What Might Monkeys Be Up To?

The Guizhou snub-nosed monkey’s night life was a secret until recently.

The Guizhou snub-nosed monkey’s night life was a secret until recently.

February 10 marks the beginning of a new year, the Year of the Snake, according to the Chinese lunar calendar. I cannot help but reflect on what I have done in the past year and contemplate what I wish to accomplish in this new year.

Last year, my research project focused on an investigation of wild Guizhou snub-nosed monkeys in China using camera traps. This work was conducted in Fanjingshan National Nature Reserve (FNNR) in collaboration with the reserve’s administration. We set up a network of over 100 camera traps to monitor, in addition to the Guizhou snub-nosed monkey, many hard-to-see wildlife species in the reserve (see post Monkeys, Leopard Cats, and Bears, Oh My!,). Some of our unexpected captures were images of Guizhou snub-nosed monkeys moving about in the middle of the night (see article in Primates). Although these monkeys are considered daytime active species very much like humans, our camera-trap data provided unequivocal proof that they are routinely active after dark. What might the monkeys be up to?

Guizhou snub-nosed monkeys’ nocturnal habit, we believe, is motivated by the need to acquire as much food as possible. In other words, the monkeys are up at night because they are hungry. To some people, this discovery may seem like a non-discovery, but many great scientific discoveries are inherently simple, and they often start out with a simple observation, like the apple that fell on Newton’s head. But I digress, back to the monkeys.

An important outcome of our camera-trap study, besides showing the behavioral flexibility the monkeys have to cope with living in a highly seasonal environment, is the need for researchers to rethink methodological designs that minimize observer bias. If we habitually observe diurnal primates during the daytime we, of course, have data that only show them being active during the hours we observe them. Camera traps, therefore, are excellent devices to augment our data collection. And, because of the amount of photographs we have, you can count on me spending much of my time this year uncovering more secrets about the animals in Fanjingshan.

My research collaborators, from left: Duoying Cui (Beijing Zoo), Marco Gamba (University of Torino), me, Yeqin Yang (FNNR), and Kefeng Niu (FNNR)

My research collaborators, from left: Duoying Cui (Beijing Zoo), Marco Gamba (University of Torino), me, Yeqin Yang (FNNR), and Kefeng Niu (FNNR)

An intrinsic part of what I do as a scientist is to assist students with their professional development. Through mentorship of students, I help foster future colleagues and, in turn, expand my network of collaborators. This past year several of my students completed their research thesis, attained a higher degree, received scholarships, and/or launched new projects. James Dopp is a graduate of the University of Vermont who worked with me in Fanjingshan in 2010 through 2012. He has been awarded a Fulbright Fellowship to further sharpen his research skills in primate conservation in China.

Kefeng Niu, a resident biologist of FNNR, continued to benefit from my coaching. In August, he successfully delivered a paper in English at the International Primatological Society Congress. The Congress also provided Kefeng a chance to meet other professionals, among them, Dr. Marco Gamba, my Italian colleague from the University of Torino. I introduced Marco and his research on primate vocal communication to Kefeng. We later invited Marco to join us in Fanjingshan to resume our wonderful discussion about snub-nosed monkey biology with China’s renowned primate expert, Yeqin Yang (see post Saving Monkeys Takes a Team). And the rest, as they say, is history, because when Marco left Fanjingshan, he had already signed a five-year research agreement with the reserve administration and gained a prospective PhD student, Kefeng Niu. Mama mia!

Cameron makes her debut as “Yi Jie Jie”

Cameron makes her debut as “Yi Jie Jie”

Recently, my mentorship pool of students included a junior from High Tech High International. Her name is Cameron Ishee, and though only 16, she is well on her way to transforming how people perceive and treat animals. Because of Cameron’s ability to speak Chinese (Mandarin), I asked her to help me create a series of bilingual video lessons for the children in the Little Green Guards program in Guizhou (see post March of the Little Green Guards). Each episode stars Cameron as Yi Jie Jie (or Big Sister Yi) teaching an English alphabet letter and about half a dozen animal-related words associated with the featured letter. To make learning memorable and fun, we segue from the classroom lessons into video segments of our Zoo and Safari Park animals. In doing so, we are achieving several objectives: introducing a world-class animal collection to underprivileged children who would otherwise never have the opportunity to travel to San Diego, and enhancing the school curriculum by teaching these children a highly valued foreign language that only children living in the more affluent urban areas of China are learning.

Our pilot episode is almost complete. Cameron and I will continue making more episodes this year. Just a little spoiler alert here, snake will be featured in our upcoming episode: “S is for Snake.”

Chia Tan is a scientist in the Behavioral Biology Division with the San Diego Zoo Institute for Conservation Research.

37

Orangutans Clyde and Cinta

We are so proud of Clyde!

We are so proud of Clyde!

Clyde is doing really great at the Rolling Hills Wildlife Adventure in Salina, Kansas (he moved there in May 2011, see post Changes for Orangutans). Clyde and Rusa continue to get along well. Both animal staff and animals alike love Clyde. He is the only male with whom female Ruse has been paired that she likes! But who wouldn’t like Clyde? He is the sweetest male, and all the girls like him (well, except Indah, of course). There is not any expectation of an offspring from them, though. Rusa has some reproductive issues that would make getting pregnant very difficult. A baby would be a happy surprise. The keeper there was telling me that Clyde is funny about his browse; he is turning his nose up at the Midwest varieties of trees and leaves.

After a few setbacks, Cinta is with all of the orangutans at the St. Louis Zoo (he arrived there in October 2012). Originally, the staff was planning on introducing Cinta to the mother and daughter there, hoping for a successful pairing with the older female. Unfortunately, the females had a different idea! While reevaluating the situation, the staff noticed that Cinta and Robbie, their 19-year-old male, seemed compatible. They were separate from one another but were sharing food back and forth and hanging out near one another. Staff never planned on introducing the two males, but they decided to try and then, later on, Robbie and Cinta could together be reintroduced to the girls.

This has proven to the best of solutions. Cinta and Robbie are now best of friends! They hang out together and share food. Just last week, staff put all four together with a much-improved outcome. ☺ Now, whenever there are any problems, Robbie steps in and defends Cinta (not that Cinta needs much help—he is much faster that the girls! Keepers are very positive about the improvements they have seen and expect things to continue to get better. We will keep our fingers crossed for a successful pairing!

Tanya Howard is a keeper at the San Diego Zoo. Read her previous post, Orangutans: Planned Parenthood.

Here’s a fun video created for our digital ZOONOOZ, available as a free app from the App Store:

62

Orangutans: Planned Parenthood

Is Indah ready to become a mother again?

Is Indah ready to become a mother again?

We have just been given the go-ahead by the Species Survival Plan for orangutans (a part of the Association of Zoos and Aquariums) to have a baby with San Diego Zoo orangutans Indah and Satu! Indah has been taken off birth control. She was on birth control because we did not want her to become pregnant while raising her son, Cinta. Typically, sons stay with their mother for eight to nine years. Indah had been implanted with a device similar to Norplant in humans, so she needed a trip to the vets to get it removed. Just like with humans, it may take a while for her hormones to balance out. We are hoping that this time next year we will have a pregnancy or may be even a baby!

The siamangs and the orangutans get along for the most part. The assertiveness of the siamangs directed toward the orangutans at feeding times is behavior seen by researchers in the wild. We do see positive interactions with Indah and the siamangs. She shares food with them (and Satu, too!). Also, she has been playing a lot with Unkie, our male siamang, wrestling and wearing him on her head! It is really amazing to watch.

Even though our female orangutans have been hand raised, they are still wild animals. Their behavior is unpredictable, and, as such, we do not go in with any of them. There is plenty of keeper interaction with each individual with a protective barrier between ape and keeper.

Tanya Howard is a keeper at the San Diego Zoo. Read her previous post, Orangutans: Change is Good.

20

Gorillas Imani and Frank

Frank will have a new buddy to play with!

Frank will have a new buddy to play with!

On Tuesday, January 22, two of the San Diego Zoo’s gorillas were moved to the San Diego Zoo Safari Park. This move was recommended by the Species Survival Plan (SSP) program for gorillas and serves to place both in a situation where they will meet and form bonds with other gorillas that are expected to make good companions for the future. The following is information from animal care staff about the move.

After a short freeway ride freeway from the Zoo to the Safari Park, where Frank was peeking through a window to check out his caretakers in the cab of the truck, he and Imani arrived at their new home. Imani is 17 and is Frank’s surrogate mother; Frank is 4½. The move went smoothly as they were transported in their own crate (which they go in every day for training sessions) and unloaded into the Park’s gorilla building. They were a bit scared when being shifted into the rooms they will have in the days until the introductions to the Safari Park’s troop, but calmed down when they realized these rooms were across from the kitchen where the keepers prepare the gorilla diets.

Imani has already caught Winston's eye.

Imani has already caught Winston’s eye.

They were hand fed some of their favorite food items by their keepers. A little later in the day, Frank and Imani were given access to a room where they could see the Park’s troop on exhibit. A lot of positive interactions were seen between the Park’s silverback, Winston, and Imani as they sat close to each other and vocalized. Frank was a little more timid, staying close to Imani but checking out his soon-to-be pal Monroe, age 1½ (who was very clingy to Mom Kokamo). Vila and Kami also checked out their new companions calmly while Kokamo strutted by, tight-lipped at this new female in her presence. The visual introductions concluded at the end of the day as all the gorillas settled into their sleeping quarters for some much-needed rest after a long, eventful day.

Much thought and discussion went into the move. The decision was made to move Imani and Frank to the Park so Monroe and Frank could buddy up as youngsters and live together when they get older in a bachelor troop, if the need arises. Gorillas typically live in single male/multiple female troops, and with a 50:50 birth ratio, there are always more males than females who need a social group in which to live. Therefore, some all-male troops must be established. This type of troop also occurs in the wild, where it is generally a transient type of social dynamic.

Allowing Frank and Monroe to bond now also provides a tremendous amount of enrichment as well as growth and development opportunities for the little guys. Gorilla troops normally have several females and their offspring, so the energetic youngsters always have playmates at hand. There is no doubt that Frank and Monroe will become best buds and will have tons of fun together.

Frank is also getting to meet more members of his family, as Kami is his paternal grandmother, and Vila is his maternal great-grandmother! Imani was included in the move because of her bond with Frank as his surrogate mom, and there is also an SSP breeding recommendation for Imani and Winston.

On Wednesday morning, Frank and Imani got to explore the exhibit for several hours. They cruised all over every inch and seemed to be having a good time, especially when they found that the trees drop figs! They also had access to the gorilla house and spent time engaged in a favorite gorilla pastime: watching the keepers work! After a couple of hours, they came into the house for lunch and the rest of the day. The troop then went out on exhibit. A great day!

April Bove is a senior keeper at the San Diego Zoo. Peggy Sexton is a lead keeper at the San Diego Zoo Safari Park.

39

What Do Primates Do?

Primate volunteers help us collect data on orangutan behavior.

Primate volunteers help us collect data on orangutan behavior.

Much of my time has been spent focusing on koala research both at the San Diego Zoo and overseas in koala habitats in Australia. However, that is not all that I do or am interested in! A few years ago, I decided to go back to focusing some of my efforts on primate research. Most of my previous work with koalas focused upon mate choice and factors that influence it, but with primates, the research opportunities at the Zoo are more focused on the social interactions within groups of different primates. Specifically, this entails undertaking a lot of behavioral observation work, otherwise known as standing in front of exhibits and recording behaviors for many hours.

As I’m involved with several different research projects, time for me is not always plentiful, as I am sure you can all relate to. In order for me to accomplish this expansion of my work, I either needed to clone myself or enlist the help of a dedicated group of individuals. For me, the choice was easy: I decided on the latter! Who are these people, you ask? They are our very own primate observation volunteers. They all come with unique backgrounds and personalities but share a singular goal: to watch primates and record their behaviors to help expand the behavioral knowledge we need to maximize welfare and bolster breeding success.

This incredible team of volunteers has helped to reach this goal by tirelessly collecting data, sometimes in the rain, and, in return, they have seen some wonderful animal behavior. Any one of them can tell you who likes to hang out with whom in the bonobo world, which, they can tell you, changes daily and sometimes even hourly! They also can tell you about the orangutan soap opera that continues day to day with Satu’s ladies vying with each other for his attention. They can even tell you which capuchins will gladly come to the front of the exhibit for a chance that someone walking by will give them attention!

These volunteers get to do what is one of my favorite things about my work: really focus upon what animals do on a daily basis. And for me, it’s particularly exciting, as I get to expand my ability to collect more data on more species of primates. Without their help, these studies would not be possible, and for that I am grateful to all of them.

If you’re at the Zoo or the Safari Park and you see someone in front of any of these exhibits with a clipboard and stopwatch, they might be one of these primate volunteers.

Jennifer Tobey is a behavioral biologist in the Behavioral Biology Division of the San Diego Zoo Institute for Conservation Research. Read her previous post, Koala Headlines.

9

Titi Monkeys and Me

The field station on the edge of Peru’s Cocha Cashu.

My pack is my pillow. I lay on the damp, leaf-strewn earth gazing up at the titi monkey, waves of nostalgia crashing all around me. In a parallel life, I could have been doing this for 25 years. Deftly, nimble black fingers gather the small fruits and pop them into the monkey’s mouth. I can see its dark eyes clearly, searching for fruit, occasionally casting a furtive glance my way. It calls to its mate, and they scamper along branches, rejoin, and resume foraging in tandem. I have found what I have been looking for the last 25 years…in a sense.

I am at our biological field station at Cocha Cashu in Peru (see Cocha Cashu: Exploring Uncharted Territory). I have given myself the gift of the day: a day to wander through the forest alone; a day for nature pure and simple. No science. No human relationships. No over-thinking. From the onset, it is my highest hope that I will experience titi monkeys. I have spent the morning walking slowly and quietly through the forest, enjoying the birds, butterflies, and occasional monkeys.

A forest good for primates. This is an ancient ficus tree that bears figs relished by monkeys.

I hear leaves rustling quietly overhead and the softest little “peep-peep-peep” that instantly brings me back two decades. I recognize the contact call that the titi monkey gives to stay in touch with its mate while foraging. The next half hour is a personal journey through time—past, present, and future.

The year is 1988. I am in my first year of grad school at UC Davis. I am in a one- hectare “field cage” observing the daily drama that unfolds between several pairs of monkeys. James and Laura—the names come back to me—are the star couple, happily pair bonded and devoted to one another. Klinger and Mabel have troubles. Klinger is retiring and fearful (i.e., a wimp) and Mabel is…a would-be cheater. She has her eyes on James. I am collecting behavioral data and working out my doctoral dissertation research with professors Sally Mendoza and Bill Mason. I am also dreaming of relocating my research to the Cocha Cashu Biological Station in the Peruvian Amazon.

One of the other primate denizens of Cocha Cashu, the brown capuchin monkey.

But this project will never be. I will instead find a field project with rattler-battling ground squirrels in California and then find my way to a postdoctoral position with San Diego Zoo Global. I will track rhinos through the African bush and study giant panda ecology in the bamboo forests of China. One day later I will become the director of many conservation projects around the globe. But I will not study titi monkeys, and I will not come to the Amazon…not for a long time.

But today I am lying on my back deep in the Amazon watching a pair of titi monkeys feed, thinking of a life that might have been. I return to camp with an Amazon-sized lump in my throat.

Ron Swaisgood is the director of Applied Animal Ecology and the general scientific director of the Cocha Cashu Biological Station for the San Diego Zoo Institute for Conservation Research.

5

Investigating Primate Malaria in the Amazon

A microscope slide shows the malarial parasite in a red blood cell red (see arrow) of a sampled primate.

When I first met Marina Bueno, I was instantly drawn to her excitement and passion for research in conservation medicine, a field that blends aspects of wildlife conservation, wildlife health, and human health. Marina is a veterinarian and doctorate scientist who works with the University of São Paulo’s Laboratory of Wildlife Comparative Pathology in the School of Veterinary Medicine and Animal Sciences. She also works with TRÍADE, a Brazilian organization for conservation medicine research, and Instituto Pri-Matas, a nonprofit organization conducting a project with golden-headed lion tamarins. Last summer, Marina spent extended time training in our Molecular Diagnostics Lab, learning how to improve DNA isolation techniques for some of her work. This is where we first discussed potential opportunities for collaboration on her projects investigating primate malaria in the Amazon.

Brazil’s Amazon region is seeing large-scale, human-induced (often referred to as anthropogenic) environmental changes that affect people and wildlife habitat. In a study conducted by Marina and collaborators, primates were surveyed across two protected field sites in the Amazon that are currently under severe anthropogenic pressure due to large construction projects that include the building of roads and dams. The idea was to sample South American primates in these sites to better understand what diseases they have and how these diseases could impact primate conservation and human health in these areas.

Marina Bueno samples primates in the Amazon for potential diseases.

They found that approximately 20 percent of surveyed primates carried a malaria-causing parasite, Plasmodium brasilianum. While infection with primate malaria generally does not harm the primates, there has been speculation that some of the primate-specific malarial parasites may not be so primate-specific. Some scientists believe that mosquitoes feeding on primates infected with Plasmodium brasilianumcould transmit the malarial parasite to humans when they bite a human host.

Marina’s research documents these malaria infections in primates, providing recommendations to closely monitor the human and primate populations for Plasmodium brasilianum infection in these areas of severe anthropogenic pressure, a situation that has been known to promote human malaria epidemics. The investigation also recommends that primates be tested for the presence of malaria infection before being relocated to other areas of Brazil for conservation or translocation projects so as not to inadvertently introduce malaria into areas where it has been eradicated.

Working collaboratively with scientists from around the world is a role that our Wildlife Disease Laboratories naturally falls into with its multidisciplinary group that includes veterinary pathologists, scientists, a molecular diagnostic laboratory, a histology laboratory, and an epidemiologist. Epidemiology expertise was provided for this particular collaborative project on primate malaria in the Amazon region. The study will be published soon in a peer-reviewed journal.

We are excited about our collaborations with our Brazilian counterparts in their quest to conserve one of the most ecologically diverse areas of the world and their search for harmony between human progress and wildlife conservation.

Carmel Witte is a senior research coordinator at the San Diego Zoo Institute for Conservation Research. Read her previous post, Epidemi-what?

The above photos are printed with permission from Marina Bueno.

4

March of the Little Green Guards

A child’s artistic interpretation of a Francois’ langur family group in Mayanghe National Nature Reserve after our first Little Green Guards lesson.

Kids are back to school. Summer is over. Just the other day, a colleague asked how my summer was. I drew a blank and responded, “What summer?” Indeed, I work all year long, and for me a year is marked by only two seasons: the field season and the non-field season. Because my field season is about to start, I am busier than ever. And while we’re on the subject of school, let’s focus on the importance of education, more precisely, conservation education, since that will be one of my major undertakings this October.

In Guizhou, China, we are launching our second module of conservation education lessons and activities for the Little Green Guards, a program designed to promote habitat and species conservation by fostering positive attitudes toward nature and wildlife in rural schoolchildren living near nature reserves. Our program is based on the fact that a child’s knowledge about animals influences his/her beliefs and behavior toward them, and pro-animal learning experiences lead to pro-conservation behavior.

Chia (left) and Bing Yang (volunteer) with schoolchildren.

Last year, we completed a first-ever survey of Chinese rural schoolchildren’s attitudes toward, and perception of, wildlife. Similar to the results of surveys of schoolchildren conducted in the U.S. and other Western countries, these rural Chinese children preferred “beautiful” and domestic animal species over those they were afraid of, like spiders and snakes. Thus, the lessons and activities we are developing to help build positive attitudes toward animals must bear these existing preferences in mind.

For instance, because these schoolchildren can see monkeys in the wild, one might expect the monkey to be one of their most favored animals. And it was! This high ranking provides us with an avenue to explore the relationship monkeys have with plants and other animals in the local habitat. As for the more noxious species, we are also cultivating their understanding of the role each species plays in the ecosystem and teaching kids that “snakes need love, too” through our lessons.

Volunteer Tianyou Yang conducts a pre-program interview with a second grader while a fourth grader looks on.

Since we began the Little Green Guards program with our partner, Fanjingshan National Nature Reserve, we have attracted several in-country governmental and private entities—Guiyang Environmental Protection Bureau, Beijing Zoo, Wuhan Sante Cableway, and China Central Television—to help us broaden our efforts. This year our “Back-to-School Special” program will end on a high note—we are organizing a schoolyard concert that will involve students and teachers as well as family members. We are stepping out of the classroom and into the hearts of family and community to make conservation a relevant and engaging topic.

Our approach is effective because we are affecting those whose lives are the most dependent on the local natural resources; these rural people also represent the majority of the country’s population. The enthusiasm we are generating is not by chance. China is primed for conservation education. The time is now, and we are ready for the Little Green Guards’ second march!

Chia Tan is a scientist in the Behavioral Biology Division of the San Diego Zoo Institute for Conservation Research. Read her previous post, Monkeys, Leopard Cats, and Bears, Oh My!

6

New Additions: Monkeys, Otters, Pigs

Spot-nosed guenon Indi hanging out on the swing in the lower exhibit

I just wanted to update everyone on some of the changes that are happening in Lost Forest at the San Diego Zoo. If you remember reading my older posts, Monkeys, Otters, and More and More about Monkeys and Otters, some of the same animals are still monkeying around in their current exhibits.

In the lower mixed-species exhibit, we still have our Allen’s swamp monkeys: Kinah, Deriai, Layla, Shaba and Nub. Our little juveniles are growing up so fast and still love to hang out with our spotted-necked otters from time to time. The spotted-necked otters currently in the lower exhibit are Mzee and Lila; however, you are not going to see them together. Mzee is Lila’s father, and we keep them separate so they don’t breed. Consequently, we rotate the two otters on exhibit, so one day you will see Mzee going down the water slides and Lila wrestling with the swamp monkeys the next. The otters don’t seem to mind at all!

You might also see some new faces in the lower exhibit, ones with blue faces, white cheeks, and white spots on their noses. These are our three, new spot-nosed guenon siblings: Indi, Chi-Chi, and Tiko. The first few weeks on exhibit, they were inseparable. They were like three monkeys in one. Wherever one went, the other two followed. You will see this close-knit behavior on exhibit. Indi and Chi-Chi are the two females. Indi has a little more meat on her bones. You will most likely see her try to take over any food situation. Chi-Chi, the smaller female, lets Indi eat her portions to keep their hierarchy balanced. But don’t worry, everyone gets enough food on and off exhibit. Tiko is the larger male spot-nosed guenon and loves to be groomed by the females. You will see him stretched out on one of the platforms with his legs and arms hanging down in such bliss. Every once in a while they interact with the swamp monkeys, but they definitely like to stay close to one another.

Spot-nosed guenons Indi, Chi Chi, and Tiko

In the upper exhibit, our adorable Allen’s swamp monkey pair, Jaribu and Ota, are doing great. Patty and Abu, the spot-nosed guenons who were in the lower exhibit last year, are now in the upper exhibit to accommodate our new arrivals. You’ll see Patty and Abu way up top in the trees where they like to hang out. Haraka and Spike, the spot-nosed guenons who used to be in this area, are now in the mixed-species area of Lost Forest with the mandrills and Angolan colobus.

And do you remember our charismatic Congo buffalo, Helen? She is still striding around the exhibit checking on what everyone else is doing or just relaxing in the back catching some Zs. Some of you might recall our spot-necked otter Khalil. He was paired with a female to start his own family and now resides at a different zoo. His mother, Pori, now inhabits the upper exhibit side. Mother otters in most cases isolate out the older daughter, and fathers isolate their sons after maturity due to competition for breeding. This is why Pori is housed alone as of now. If we get a breeding recommendation to breed Pori, then she may be paired with a male. For now, we wait and enjoy her company with the rest of the animals in the upper exhibit.

African spot-necked otter Pori grabs a fish in the deep pool while Jaribu watches.

Last but not least are our red river hogs! Helen’s red river hog friend from last year, Oboi, was transferred to breed with females at another zoo. Now Helen has some new friends to snuggle with. Our new additions include Hamela and Amy. A little shy at first, they warmed up to our older red river hog residents of a couple of months, Tarzan and CT. Talk about an inseparable foursome! You will love seeing this cuddle fest in the back of the exhibit. All four pigs and Helen took to each other rather quickly. Even behind the scenes, Helen and the pigs share the same beds, making it a cute group of “red” sleeping together. Helen is such a mom figure to these piggies!

(Clockwise) Helen the Congo buffalo, red river hogs CT, Hamela, Amy, and Tarzan

Well, hopefully you can come down and enjoy the new company of animals as much as I do. I randomly toss treats to the critters in the late morning/early afternoon, so come by and say hi!

Jasmine Almonte is a senior keeper at the San Diego Zoo.

4

Homecoming in Cocha Cashu

This is Theo (or Thea?), a young otter born last year in Cocha Cashu. The giant otter habit of periscoping allows us to document their unique throat patterns.

The howler monkeys wake me up before my alarm clock does. For a moment, I’m disorientated. Oh, right, I’m in Cocha Cashu in Peru. As I dress, I try to decide how I would describe the howlers’ epic serenade to my kids. Like a train roaring through a tunnel? A powerful wind rushing through the tree canopy? Awesome in the true sense of the word?

The day is just beginning when I meet Russ at the lake. We collect our gear and gingerly step into the wooden canoe. It sits low in the water. Any sudden movement risks an early bath. The trick is to smoothly fold yourself into a cross-legged position on the bottom. We eventually manage this (not so smoothly), and gently push ourselves off. The canoe, shaped like a hollowed-out needle, slides soundlessly from the shore. Sitting in the stern, I grip my crudely carved paddle and push against the water, accidentally knocking against the boat and causing Russ to clutch the sides. But soon I fall into a rhythm, five strokes to starboard, five to port, and the canoe stabilizes. We relax. The paling sky, the murmur of our passage, the darkly sleeping forest, it all seems so familiar. It is as though I’ve never been away.

A juvenile striated heron pretends to be invisible as we approach.

Almost immediately, we glide past a tree in which white-fronted capuchins are feeding. There is still not enough light for photography, so I take pleasure in simply watching. Russ does not speak, for which I am grateful. The beauty around us is enough. We slowly drift on. Howlers on one shore of the lake begin their unearthly concert, and a group on the opposite shore answers. The forest is quickening. Far off, I hear the soulful hiccupping of crying babies; correction, dusky titi monkeys. A hoatzin shuffles in overhanging branches, rasping softly. Sunlight now gilds the trees, and their leaves turn a luminous green. A striated heron stands frozen at the edge of a patch of floating grass. I touch the water with my paddle, and the canoe whispers forward. Russ and I take photos of the heron until, losing heart, it flies off.

Then I hear them. I hold my breath. Yes, there it is again. Unmistakable. Now I’m tense with anticipation. I know what to look for and scan the water’s surface ahead. It reflects the tree line perfectly, such is its stillness. But at the grass edge to the left I see it distort and shimmer. Then I hear a sharp exhalation, and a wave bulges toward us. They’re chasing fish. Russ and I see the small head simultaneously. Two. No, three giant otters! I reach for my camera and wait. Sure enough, they soon spot us and head directly toward us. As they come closer, they begin to zigzag, studying us from all angles. One exhales explosively and ducks under. Another propels its upper quarters straight out of the water—periscopes—and I quickly take a photo of its throat pattern. To my delight, I recognize this male. I knew him as a demanding cub in 2002, in nearby Cocha Salvador, Manu National Park’s best-known oxbow lake. I named him Diablito—Little Devil. Now, a decade later, we meet again.

The third otter also snorts loudly and periscopes. This individual was born in Cocha Cashu in 2009 and is Diablito’s daughter or son. Soon I have the throat patterns of all three. Gently, quietly, I paddle backward, letting the otters know that we mean no harm. The important business of hunting soon distracts them, and they continue foraging along the grassy shore.
I take a deep breath. I love seeing giant otters, the subject of seven years of conservation work, but actually recognizing an individual from my former life is thrilling. And I’m happy that the lake still harbors a resident giant otter group as it has done for as long as research has been carried out at the Cocha Cashu Biological Station.

As we make our way back to the station, a pair of macaws flies overhead and a cormorant croaks rudely. My paddle dips into a large clump of fat, squirming tadpoles. They fan out, bobbling the water surface. The lake is humming with life, including biting beasties. I’ve been so caught up with the otters that only now do I feel the burning itch of several bites on my arms and neck. But it’s not worth stopping for repellent—our breakfast is calling us.
The canoe nudges the station’s jetty, and Russ pulls us along it. He climbs out, stretches, and turns to face me. “That was wonderful. Thank you,” he says. Pleased, I beam at him. As he walks off for his coffee, I take a last, long look across the lake and sigh contentedly. I’ve come home.

Jessica Groenendijk is an education and outreach coordinator at San Diego Zoo Global’s Cocha Cashu Biological Station in Peru.