A keeper in a pickup truck had just arrived on the scene and parked at the peak of the incline that I was ascending. Just then, Sally approached the truck and climbed into the cab through the passenger window, as the keeper dove out the driver’s door. She seated herself behind the steering wheel, wildly swiveling it to and fro, like a kid mimicking an adult driver. Then she started to ratchet the gearshift on the steering column, as if she was ripping off a tree branch. I thought the next scene in this movie would have the pickup truck, orangutan at the wheel, jolting out of gear and heading for a downhill finale into the ape exhibits at the bottom. But, instead, she clambered out of the truck and continued her journey toward the front entrance.
By this time, several more employees had arrived in the area, taking cover in several nearby buildings, peeking out of doorways, trying to spot the escaped ape. I hoped that the security guards were taking this all in stride and would give us time to capture her unharmed before taking any extreme measures. As Sally left the truck, I followed her. She was so enthralled with her adventure that she didn’t notice me trailing behind, and she stopped several times to pull up handfuls of flowers from planter beds along the path. She alternately knuckle-walked and ambled upright, passing the Bird Yard cages like a regular visitor.
Then, just as she lifted her leg to climb over a low wall along the Gibbon Island water moat, I fired the dart. It struck her in the hind leg below the right buttock. She swatted at what must have felt like a bee sting and puckered her lips. By the look on her face, she seemed to realize that her picnic was beginning to go sour. Reversing direction, she headed back toward the ape exhibits, a dart dangling from her leg. I was unsure if it had actually discharged its drug dose, and I quickly loaded up another. Within only a few minutes, however, the effects of the drug began to show; Sally began to look around overhead as if she were considering a vertical escape in one of the many surrounding trees.
As she stumbled her way toward a group of small aviaries, she chose one and scaled the front wire, having difficulty with her finger holds as she went. When she reached the roof, she had little zest left in her beyond bracing herself from falling over. Mired in a chemical meltdown and at the end of her freedom run, she was unceremoniously lowered down a ladder in a cargo net and toted back to her bedroom quarters. The next morning I visited her before she went back on exhibit and offered her a piece of cinnamon gum. She took it from my hand, stuffed it into her mouth, and began to chew. No hard feelings.
The cause of the escape was human error. Sally had not returned to the sleeping quarters the evening before and had spent the night topside in the exhibit. Missing the note from yesterday’s keeper, the regular keeper entered the exhibit and started to clean. When he left to get some supplies, out the door went Sally. Unaware of the morning’s excitement, the visitors awaiting the opening of the entry gate spread out for their own adventures in the zoo.
Zoo veterinarians sometimes have to be spoilsports to get their work done while providing for the safety of others. Until the construction of the new San Diego Zoo Hospital in 1977, it was difficult to accommodate hospital visitors because of cramped quarters and work areas. Special provisions were made in the new hospital to provide viewing areas behind glass walls to host special visitors and zoo staff while preserving safety. When we began to do a dental surgery on a tiger or work on animals such as a gorilla or a large crocodile, zoo staff members sometime came out of the woodwork to get a peek at one of these creatures up close.
On a day that we worked on a black cobra, the news traveled fast throughout the zoo. Most of our work on venomous reptiles was done in the main reptile house, and we never hospitalized poisonous snakes outside the holding areas there. Occasionally, though, one would come to the hospital for X-rays or some other diagnostic procedure. A researcher at the local medical school had made a special plea for a sample of cobra blood for his work on coagulation and cancer. I was unenthusiastic about handling poisonous reptiles to begin with, but, in the interest of science, I agreed to accommodate his request. My caveat to the curators was that the animal would be fully anesthetized to increase the safety of the procedure. The cobra arrived from the reptile house in what is called a “hot box,” a sturdy, red, lockable carrying case for venomous snakes. It had metal-screened air holes, stout carrying handles, and a special lid with a double door—the first solid and the inside one screened.
The keeper carried the red box into the hospital’s large procedure room and placed it on the floor next to the examination table, as if he were setting down a land mine. As we started to talk about the next step, a few onlookers crept into the room for a closer view. I asked everyone except the reptile keeper to leave the room—after all, this was a dangerous job for “experts” only. Now that the distractions were gone, the plan was for the keeper to remove the cobra from the box by securing its head in a straplike noose at the end of a snake handling stick, and then place the snake on the exam table. This would then allow me to insert a plastic tube into its windpipe (which in snakes is in the front of the mouth) and pump the snake’s lungs full of anesthetic vapor.
Everything was going as planned until that point, and the onlookers were safely sequestered in the viewing area, noses pasted to the glass. Just as I was manipulating a forceps to spread the snake’s jaws and insert the tube, it suddenly slipped from the restraint strap and slithered atop the anesthetic machine next to me. Drawing itself into a coil, it opened the hood on its head and neck in a chilling display. We jumped back and reconsidered our plan, while the onlookers, now grateful that they had been ejected, pressed harder on the glass.
After recapturing the cobra and placing it back in its box without further incident, I encased the whole container in a trash bag and filled it full of anesthetic vapors until the cobra was safely unconscious. While many venomous snakes have sizeable heads, some cobras have small ones in relationship to their necks, making the strap-restraint method less reliable. That was the last research cobra I agreed to handle. I limited my future research projects to more predictable rattlesnakes. Our zoo pathologists would not necropsy a venomous snake until it had first been decapitated, yet another luxury not enjoyed by the clinical veterinarians.
The San Diego Zoo, in keeping with its large display of poisonous snakes, had a fairly elaborate emergency response plan in the event of a venomous snakebite. As a first precaution, poisonous snakes were not to be handled in the reptile house unless two qualified keepers were present. In the event of a bite, the first measure to take place was the activation of the alarm system, which went straight to the zoo security office and to an alarm bell on the roof of the reptile building. The immediate priority, before any first aid treatment took place, was to secure the guilty snake in order to avoid injury to personnel that came to respond to the accident. It was also critical to determine the snake’s identity with absolute certainty. The local medical center supposedly had at least one staff physician on duty in the emergency room who had been briefed on snakebites, and written protocols were kept in notebooks in the hospital emergency room.
It was up to the zoo to maintain its own stockpile of exotic snake antivenin and essential that it be within the product expiration dates so that the physician would not decline its use. These biologicals are often produced by repeatedly inoculating horses with small doses of venom and harvesting the serum from their blood which then contained antivenin properties to neutralize the effects of the toxins. In the event of a bite, a detailed evacuation plan was in place, including access for an emergency ambulance to the reptile house. The snake-bitten person, along with the cache of the appropriate antivenin, was to be transported to the hospital to find (hopefully) a knowledgeable and willing physician awaiting their arrival.
Despite all of the ludicrous folklore about tourniquets, cutting, suctioning and poulticing bites to remove snake venoms, the basic procedure is to keep calm, keep the affected area elevated, and seek prompt emergency care. However, in the 1930s, lacking competent kn
owledge, most of today’s prohibitions about bite treatment were actively promoted. The San Diego Zoo reptile department’s old advice to the public concerning rattlesnake bites was published as follows:
Make a cross incision over each fang mark to the estimated depth of the fang puncture
Suck for at least half an hour
Do not give whiskey or alcohol in any form
Give a cup of strong coffee or a teaspoonful of aromatic spirit of ammonia
Do not place a dead chicken, tobacco juice, gun powder, or any other remedies on the bite
Always cut and suck.
Very wrong about everything else, they were correct about the chicken, tobacco, gunpowder, and whiskey.
No human emergency room ever finds venomous snake bites routine. In some cases, physicians have declined or delayed giving the antivenin because of unfamiliarity, or for fear of causing allergic shock, especially after reading the labels, which warn “Do not administer to patients allergic to horse serum—this may precipitate a fatal anaphylactic reaction!” Faced with a choice, most reptile keepers would rather take their chances on the risk of death by horse serum allergy rather than by snakebite. Some of the most toxic snakes can have lethal effects within only minutes from cardiac, respiratory, and muscle effects, making medical complications from a product more academic than real. Virtually all zoos in the United States decline to house a venomous snake for which they do not stock or have ready access to antivenin in ample quantities. Reptile keepers in zoos are a special breed, marching to different drums than bird and mammal keepers. A few of the San Diego reptile keepers enjoyed driving out into the local desert in the evening to see how many rattlesnakes they could apprehend warming themselves on rural highways in the desert night and then simply release them—just for fun, of course.
The giraffe is one of the few animals in the zoo that is known to never utter a sound, making no audible vocalizations even when a mother is stressed and agitated by separating it from its offspring. If you were led blindfolded throughout the animal barns in the zoo you would be know immediately when you arrived at the giraffes, since they have a unique, pleasant odor entirely distinct from elephants, zebras, rhinos, and other herbivores. Occasionally, giraffes have mishaps and injuries in their exhibit areas, but treating sick or injured giraffes is one of the least desired of zoo veterinary tasks, for obvious reasons of size and altitude.
Their inconsistent responses to immobilizing drugs also make them high risks, and a drugged giraffe can topple over, causing serious injuries to itself and to those trying to break their fall. Our largest San Diego Zoo giraffe was a male named Topper, who stood seventeen feet tall. One of his ongoing problems was the notable overgrowth of his hooves, which were getting uncomfortable and unsightly. Despite our desire for a special restraining chute to attempt to whittle away at his problem feet, it would be some years before one became a reality. Such specialized equipment has helped greatly to move, handle, and crate animals such as apes, elephants, and a variety of antelope species. The only chance I had at trimming Topper’s feet came on a moment’s notice, when a radio message alerted me that Topper was unconscious on the ground. By chance, I was about a minute away from the exhibit, and on arrival I saw the big giraffe stretched out flat, his overgrown hooves staring me in the face.
Topper had fallen after becoming entangled in a rope and pulley that had just been installed on an exhibit palm tree earlier in the day by a creative zoo gardener. The intent was to facilitate hoisting his plant browse up a tree for him to feed. Despite their long necks, it is difficult for giraffes to feed off the ground, and drinking water in the wild is also an awkward maneuver for them. Like all other mammals, giraffes have only seven cervical bones (vertebrae) in their necks; they just happen to be very long ones. Captive giraffes are given elevated feed bunks and drinkers.
Topper, however, managed to place his head and neck between the ropes and the tree and panicked as he turned to leave. Lassoing himself and losing his footing, he knocked himself out cold when he hit the ground. The keeper and I ran to Topper’s side, and I took his pulse as I supported his huge head in my lap to check the pupils of his eyes. My first thought was that he had broken his neck, but as I watched, his breathing began to return to normal in a few minutes. He rolled his eyes and flicked his huge eyelashes as he slowly moved his head. I sat there on the ground staring longingly at his overgrown hooves—my hoof-trimming tools were in my truck nearby, but the opportunity was fading. As Topper regained his faculties, he raised his head above us and succeeded in stumbling to his untrimmed feet with our assistance as we pushed on his rump. In lieu of chemically restraining him for footwork, we installed a specially roughened concrete slab in his favorite feeding place, and his foot overgrowths gradually subsided to a manageable level as the slab wore them away. The restraint chute didn’t come until later, long after our aging Topper went to that big giraffe savanna in the sky.
A telephone call came late in the afternoon on my day off that Freckles, our female giraffe, had stepped backward into the outdoor exhibit and tumbled into the concrete moat that separated the exhibit platform and the public viewing rail. Stunned and confused, Freckles was in a panic. When I arrived at the zoo I received an account from a visitor: “She was just standing there, dozing off and chewing her cud. I was watching the wad of food travel up and down her neck, then, without warning, she seemed to forget where she was, stepped backward, and fell like a tree.”
Slightly banged up with some visible abrasions on her head, Freckles was pacing to and fro, trying to figure out how to extricate herself from the moat to rejoin her mates. The moat itself was five feet deep and shaped like a U in cross-section; it had been constructed by laying wire mesh over shaped earth and spraying it with concrete. It had no exit, coming to an abrupt stop on each end of the exhibit perimeter. She made several futile attempts to climb out, but gave up in frustration after taking several pathetic tumbles for her efforts, adding more bruises and scratches to her legs and feet.
As night fell and we all stood and watched, Freckles paced the moat. Given the coming darkness and her spooky demeanor, it would be impossible to rescue her that evening, so we set about preparing for an overnight vigil, spreading straw over the moat bottom and trying to comfort her with some of her favorite treats of carrots and apples. She was far from being in the mood to eat. Finally, in exhaustion, Freckles collapsed on top of her bruised and spindly legs, and gave up. At first, her recumbence came as sort of a relief to us all, and she seemed to recover from some of the excitement. Her breathing became more regular. But after an hour, I became concerned—her immense weight upon her legs, combined with the hard concrete beneath her, spelled impending trouble in the form of nerve paralysis, which could make it impossible for her ever to stand again. Surrounded by our flashlight-toting rescue party in the moat, she lay there and resisted our efforts to push and prod her back onto her feet. Meanwhile, her lower legs began to feel cold to the touch.
Running out of time, I resorted to a piece of equipment that I had never used—an electric cattle prod. This device looks much like a flashlight, but instead of a light on the end it terminated in two metal electrode points. I retrieved it from a storage drawer at the zoo hospital and installed fresh batteries, hoping this would be the stimulus that would get Freckles up. Climbing back in the moat with her, the first shock applied to her rear got her attention, but still she wouldn’t stand. Going for broke, I inserted the probe into her rectum and pressed the on button. Contact! Her eyes opened wide. As I switched it off and on, her ears twitched wildly, and she rocked herself free, staggering to her feet. She remained standing all night long. When dawn came we built an incline ramp out of plywood and hay bales, and she gladly clambered back into the exhibit to rejoin her companions in the barn. The moat was then partially filled with dirt to reduce its depth to only three feet, which was safe enough—even for a narcoleptic giraffe.
Many other animals have had encounters with zoo moats, includ
ing the San Diego Zoo elephant shown at the beginning of this chapter. Fortunately, she climbed back into her exercise yard without serious injury. The moat hazard was later eliminated from the exhibit.
Elephant climbing out of moat after a fall at the San Diego Zoo
Some of the medical problems involving zoo animals are more like detective mysteries than combat adventures. For reasons that were only conjectured, the zoo’s polar bears were turning green. Furthermore, this was not the first time that they had taken on this verdant hue—it seemed to happen annually. To complicate the plot, there were anecdotal reports from zoos in Europe and Australia of the same phenomenon, yet no one had a factual explanation for it. For lack of a more definitive title, I referred to it as “The Green Polar Bear Syndrome.” One idea was that there was too much chlorine in the water, which was distorting the hair color chemically. Another was that green algal slime around the wet parts of the exhibit was rubbing off onto their hair coats.
Life at the Zoo Page 23