The Hippo with Toothache (3 page)

From time to time thereafter, when I went to the chimp building, I'd wander out to the exhibit first. Hondo often
greeted me at the glass, sitting quietly in front of me and sometimes playing our version of charades. The visitors would all gather around excitedly and ask questions about what he was saying to me. I figured anything he really had to say to me probably couldn't be repeated, but smiled inwardly at the idea that they might harbor a belief that zoo vets were real-life Dr. Dolittles and could simply “ask” the animals what was wrong with them. The truth is sometimes we wish we had a crystal ball.

One day, the keepers noted that Hondo had taken on a new habit: head-standing. I went to the exhibit and he came over to the glass for a visit. Rather than sit with me, though, he stood up and pressed the top of his head onto the grass as if looking backward between his legs. He kept this up for several minutes, stopping only to look up and see if anyone was still watching him. There are two primary causes of head-pressing in animals: head pain and liver disease. Knowing that Hondo had a cataract in one eye, we wondered if he might be developing glaucoma, a painful buildup of pressure within the eyeball.

Our consulting veterinary ophthalmologist kindly offered to donate his time for this interesting case, and we anesthetized Hondo for a complete examination. The general exam checked out well, but the ophthalmologic exam confirmed our suspicion: the long-standing cataract had caused severe, untreatable glaucoma, and the eye needed to be removed. After the diagnostic procedure, the ophthalmologist offered two options. We could remove the inner workings of the eye, leaving the outer shell in place and filling the space with a silicone rubber-ball prosthesis, or we could give him a
false eye prosthesis used in human medicine—the kind that can be taken out and popped back in at will.

I looked up at this quiet, knowledgeable eye doctor and wondered why a veterinary ophthalmologist would ever offer the latter option. Ophthalmologists routinely perform amazing procedures that restore function to this complicated organ, but there are some tools in their tool belt that simply aren't practical in the animal world. They know so much about the eye, in fact, that they can identify a species by looking at the retina, inside the eye. We had to learn this skill in vet school ophthalmology class, as if at some point in our veterinary career we might come across an eyeball—rolling around on the ground, for instance—that needed to be treated and wasn't currently attached to the species to which it belonged. I momentarily contemplated the hours spent rummaging through the bushes to find the fake eyeball every time Hondo yanked it out to throw it at someone, and opted for the stay-in-the-socket prosthesis.

The surgery went well, and Hondo's head-standing ceased immediately. His postsurgical care, however, required daily visual exams and eyedrops. I visited him often in his holding area, where, eyeball-to-eyeball, I could check the surgery site and take follow-up photos without the intervening glass. One day, with little more than the expensive camera equipment between us, I realized that he had stopped spitting water on me. How could that be? After all the years of spitting when I was careful not to even look at him, the recent weeks of anesthetic darts, surgery, frequent exams, antibiotic treatments, and eyedrops had somehow improved our relationship. Not only that, Hondo readily approached to sit with
me, giving up the opportunity to impress the chimp troop by humiliating me with a mouthful of water.

On one visit, when Hondo's recovery was nearly complete, he began another new ritual. He reached his index finger through the mesh, as if asking to touch my gloved finger. When I finally mustered the courage to allow him to touch the very tip of my finger, he held it there, staring at it, as if fascinated by my latex skin.

The keepers started making jokes about our relationship, asking me to visit him even when he didn't need a vet check. Hondo had a well-known fondness for certain women, and now, apparently, I was one of them. I secretly relished the fact that here was a zoo animal that might just like me. When chimpanzee annual physical exams came around every year, I made sure I wasn't the one to shoot Hondo with the dart gun. The chimps take this very personally, and are masters of dart evasion. Once you've withstood the screaming, lunging, fecal projectiles, and wall-beating long enough to deliver an accurate shot, you have to move quickly in case the chimp decides to throw the dart back at you. I've seen one dramatic female pull her dart out, approach the wire mesh, vocalizing pathetically, sit down, squeeze the tiny hole in her thigh, touch it with her finger, and show the drop of blood to her keeper, drawing coos of sympathy before she fell asleep. I didn't want Hondo to associate me with this indignity, so I stayed out of sight until he was asleep.

One year, during Hondo's physical exam, I felt a lump. It was a large, very firm area of his liver near his rib cage. I swallowed hard, prepped him for minor surgery, and took a needle biopsy of his liver through the skin. A few days later,
with the pathologists' report in hand, I had the dismal job of talking to the keepers about Hondo's diagnosis. It's hard to imagine the level of emotion that develops between keepers and these intelligent, sentient close relatives of ours. My bond with him was special, but I bounced around the zoo every day treating hundreds of different mammals, birds, reptiles, and fish. His keepers spent every daylight hour with the chimp troop, training, feeding, cleaning, and communicating with them. They were family.

I explained to the somber group that Hondo had hepatic amyloidosis, an accumulation of inflammatory protein in the liver. The cause was unknown, and there was no specific treatment for it. The only thing we could reasonably do to help him would be to keep him out of fights—a natural part of chimp culture—because the liver was involved with blood clotting. He could bleed to death from a serious bite wound.

The keepers and curators decided to separate Hondo from the unruly female chimps, so he could lead a quiet life with Jonathan, the homely and mischievous young male. There was no way to know how long Hondo would live. At the request of the teary-eyed keepers, I visited him in his holding area, and was heartbroken to find him lying on his back, looking weak and in obvious pain. When he saw me, he reached his index finger through the mesh. I offered mine, and he stroked my finger slowly. I felt powerless.

But Hondo didn't. Being retired from the difficult job of keeping ten cranky, argumentative female apes in line agreed with him immediately. He and Jonathan spent their days swinging from fire hoses, eating giant lettuce leaves, throwing dirt, wearing their play socks, and basking in the sun in
their enormous exhibit. Hondo gained weight, grew more hair, and looked healthier than ever. A year later, he was reintroduced to the troop, and regained control of his females. He remains that way today. He's not cured, but perhaps the time away from the troop reduced the stressors in his life, making it easier for his body to fight the liver disease.

I've been away from the zoo for nearly two years now, and I miss Hondo and his comrades. When I have the chance to visit, I head straight for the chimp exhibit. He still gets quiet and comes over to have a chat with me. I know he misses me too—because, well, he did spit on the new veterinarian.

Barbara Wolfe grew up in Cincinnati, Ohio, and avidly read animal behavior books as a child. She received her bachelor of science degree in molecular genetics from the University of California, Davis, and her veterinary degree followed by a PhD in reproductive physiology from Texas A&M University. Dr. Wolfe's interest in zoo medicine began with her research in assisted reproduction of endangered species, which has ranged from antelope to cats to elephants. Board certified by the American College of Zoological Medicine, she has worked as a researcher and veterinarian for the National Zoo and the North Carolina Zoo, and is currently the director of wildlife and conservation medicine at the Wilds in Cumberland, Ohio. She is an associate editor for the
Journal of Zoo and Wildlife Medicine
, serves on the Wildlife Scientific Advisory Board for the Morris Animal Foundation, and still finds animal behavior fascinating.

A GREEN MORAY
eel was donated to the New England Aquarium by a bartender from a neighboring state. For years, the eel had lived in a tank next to the bar, but it had begun to outgrow its home.

In the wild, green morays are found in warm marine habitats such as rocky shorelines and coral reefs. They are solitary fish, spending most of the day hidden in crevices and emerging at night to hunt fish, shrimp, crabs, or cephalopods. From what I could gather, this eel was no shrinking violet. It had been a favorite among patrons, who would regularly check on it during their bar visits.

When the eel first arrived at the aquarium in the late 1990s, we set up a large holding tank along a back wall of the gallery. There it was quarantined from other fish in the
collection until we were sure it was healthy and doing well in its new environment. Soon after its arrival, it settled in behind the rockwork of the tank, as eels often do.

For the first several days, the eel hid in its nook and refused food. This is not uncommon for some fish, especially after a move. The days lengthened to a week, and then to two weeks. The eel stayed hidden and would not emerge to eat.

It had come to us with very little history about its eating habits. The diet must have been fairly balanced, considering it had already grown to nearly three feet in length—or roughly half adult size. Maybe someone periodically tossed it a couple of chicken wings.

With aquatic animals, ensuring good housing, water quality, and nutrition is critical to keeping them healthy. Some robust eels can fast for many days, even for a couple of weeks after a major environmental change. With longer fasting periods, though, the eel's general health could become compromised.

The aquarists started trying all of the tricks of the trade to get this eel to eat. They enticed it with a variety of foods of different sizes, shapes, and flavors. They tried chopped capelin and herring, whole shrimp and pieces of squid, even live bait, but the eel showed no interest. The water quality was constantly monitored to ensure all parameters were within the preferred ranges for eels. The aquarists even tried covering the tank and dimming the lights to reduce stress to the eel and, some of them joked, “to simulate the eel's previous dark barlike ambience.” But all the efforts were to no avail. The moray refused to eat.

In the third week, the aquarists were growing more
concerned and I got more involved. Could the eel's lack of appetite be related to a medical problem? We discussed diagnostic options, including blood work and parasite screening, as well as possible treatments such as tube feeding. We decided to examine the patient, which requires sedation in eels unless one is particularly proficient at holding on to a slippery, mucus-coated, snakelike animal with sharp teeth.

We netted the eel and transferred it to a covered bucket of tank water with dissolved anesthetic powder. An air stone bubbled in the water to keep it adequately oxygenated during the procedure. The first signs of sedation became evident as the eel's gilling rate slowed and it began to lie on its side. Within a few minutes, it was relaxed enough to be held safely out of the water without it struggling.

I thoroughly examined the moray, checking for any evidence of health problems. Its pale green skin was coated with a thin layer of mucus, which is as expected for these animals. I didn't see any fraying or irregularities in its long ribbonlike dorsal fin or tail. Its abdomen did not appear to be distended or otherwise abnormal. Its gills were a normal deep red and its mouth, with all of its teeth, looked fine. As with any routine fish workup, I collected a small sample of gill tissue and feces, as well as a scraping of skin mucus, to evaluate under the microscope for parasites, but saw none. I took a blood sample from its tail vein, but the results showed no abnormalities—no elevated white count or anything else that would suggest illness.

After collecting our diagnostic samples, we passed a small rubber tube through the eel's mouth into its stomach and injected some fish gruel. At least we could give it some nutrition
that day. Then we placed it back in its tank, syringing salt water over its gills to reverse the sedation. Within a few minutes, it started to swim on its own. Before long, it settled right back into its hiding spot behind the rockwork.

As I sat there worrying about this eel, I found myself remembering the more mundane roles fish played in my childhood. My earliest experiences with fish were probably eating fish sticks, those processed finger-food wonders. During my elementary school days, fish were the small minnows my brother and I scampered through creeks to catch. When I was a bit older, fish were the three-inch sunnies we'd proudly display for the camera when fishing with Dad. Fish were the prey of gulls and gruff-looking old men casting off the jetties of Long Island Sound.