UNDERWATER WORLD
quickly set up shop at the University of Melbourne, occupying my corner of the Australian Venom Research Unit. This lab had been established by Australian icon Struan Sutherland after he retired from the Commonwealth Serum Laboratories, where he had headed up antivenom development and clinical consulting for many years. Not only was he responsible for key antivenoms, including the notoriously difficult-to-develop funnel-web antivenom, but he was also the discoverer of the pressure-immobilization form of venom-emergency first aid. He was head of Immunology Research at the Commonwealth Serum Laboratories for twenty-eight years, until 1994, and then founder of the Australian Venom Research Unit at the University of Melbourne. He died in 2002, a year before I took up the position as Deputy Director. It was quite an honor to work there. I set about organizing many dusty boxes. Contained within a group tucked away in the far corner of a storage closet, I came across venoms that had been stored in dried form for decades. I added these to my growing “to do” list and moved on.
Hungry for more discoveries and thirsting for new playgrounds, I started exploring a new research field—that of fish venoms. But first, I acquired a trio of dingoes: two that had a very small amount of dog in them (less than 10 percent), and one that was not only pure, but from the wild.
The first two were a male called Norton and a female I called Mera, while the pure female I named Cleo. Norton and Mera were strays, each having shown up at different properties and ending up at the local animal shelter. The tattoos on the inside of their ears indicated that they had been someone’s pets at one time or another. Perhaps they had wandered off; perhaps they were abandoned. There was no way to tell. But they were obviously well accustomed to people and quickly settled into my house.
Cleo, however, was a different kettle of fish entirely. I got her from the Alice Springs animal shelter. She had been dropped off there by a family who lived on a large rural cattle station. Prior to that some Aboriginals had taken her out of a den when she was only a couple of months old. They had kept her for three weeks before abandoning her at the cattle station. The family had kept her for four weeks and she had seemed to be settling in well. That was until one fateful day when they let her out for a pee. Twenty minutes later they looked out to see that she had merrily slaughtered all fourteen of their chickens. So it was off to the shelter. My mate, Rex Neindorf, found out about her and rang me to see if I could take her, with full disclosure of her past. Based on my experience with the hybrids, I naively thought I had what it took to tame a wild pure dingo.
The difference between the hybrids and the pure dingo was astounding. Even such a little bit of dog had a remarkable effect upon temperament and behavior. They were very “doggy,” and actually trainable. This is why in the wild the crosses become such nuisances, since they don’t avoid contact with humans like pure dingoes. In contrast, Cleo was like a dog-shaped, orange-colored, recalcitrant jungle cat. She was very sweet when she wanted to be; other times she was more aloof than even the most socially dysfunctional house cat. Trying to scold her was like scolding a rock. She would stride majestically away, tail raised, and shoot me a brown eye. Collectively, however, they were an absolute delight to be around. I just had to make a few modifications around the property, starting with a ten-foot-tall metal-mesh fence with a three-foot in-slope at the top. The entire fence was then electrified to keep them from digging under or tearing the mesh off the posts. This gave my Mt. Dandenong property a certain fortress look.
By and large, the dingoes stayed contained, with only a few notable escapes. One instance in particular stands out. Cleo got out at 4 a.m. and started hunting the goats on the neighboring property. I let Mera out to act as an attractant for Cleo, since the two were usually inseparable. Their teamwork struck again, but not in the way I intended. Mera instantly shed her dogginess, let her dingo side take full control and started hunting too. Australia has a one-strike-and-you’re-dead rule when it comes to dogs harassing livestock, and this would be strictly applied to captive dingoes. They were not trying to deliver crushing bites like a dog would; rather, they were trying to use the uniquely dingo, very long and blade-like canine incisors, to slice at the back of the legs and sever a tendon. When Cleo was distracted by one of the goats, I took the opportunity to do a superman fly-through-the-air and crash-tackle her, face-planting in the goat-crap-infused mud in the process. Cleo didn’t struggle, as she knew the game was up, and the little traitor Mera instantly morphed back into her doggy alter ego.
Dingoes were not the only Australian mammal I really liked. Wombats also caught my eye. A midnight drive through the Acheron Forest was always productive for spotting them. I never tired of seeing these gentle giant herbivores, which were absolutely entrancing. On a clear full-moon night they could be easily seen just from the heavenly glow. “Under the Milky Way” by The Church was something played at least once (but usually several times) a night. It was a long stretch of gravel road. I would enter in from near Marysville, exiting near Warburton. I would spend around four hours there. This was one of my havens in the world. I always set up little emotional bolt-holes across the world; somewhere dear to bail to when things got a bit too much.
Acheron was an appropriate name for this spooky wonderland. Unlike reptiles, wombats were not seasonal, as these mammals always needed to eat copious amounts of plant matter, especially some of the roots that they considered tasty.
These furry tanks were like me: they would travel from point A to point B by going through things rather than around them. I could relate well to this method. This is not to say that they could not utterly fuck-up a person. Make no mistake about it, they are very dangerous animals. In captivity, babies are loveable little wonderbutts, such as Bean at my mate Stuart Parker’s wildlife park in Ballarat. But as they age, they become solitary in the wild rather than forming herds like many other herbivores. Because of their eating habits, they have incredibly powerful jaws and strong teeth. I knew of a zookeeper who’d suffered a bite to the face that resulted in a crushed mandible and carved out cheekbone section; and another who had experienced a bite to the forearm with both the radius and ulna bones broken, with the radius being a compound fracture. So, I mostly viewed the wombats from the confines of my car, which did not seem to bother them nearly as much as if I stood near to them. I could roll right up on them. Their blas? attitude to cars does not help wombats dying from motor vehicle hits.
I would also net out the rainbow trout introduced for sport fishery. I have nothing against the stocking of streams but not in fragile alpine forests that are refuges for rare frogs, as was certainly the case in the Acheron. Trout have to eat something and naive small frogs and their tadpoles were on the menu, so the fish had to go. I and the other members of the Trout Liberation People’s Front would conduct midnight raids in the creeks, making them safe for frogs. The liberated trout were fed to my Mertens’ water monitor lizards upon returning home.
One time I was out with my mate Kim Roelants, who was over from Belgium. Early in the drive we came across a big road-killed wombat. I told Kim that whenever we came across any sort of road-killed marsupial, we always checked for a joey in the pouch. So off he went into the darkness. In the low light, he relied on feel to find the pouch, sliding his hand around until he came to a moist opening. Only it was not the pouch. What had happened was that in the boiling summer heat, the insides had cooked. The body became swollen like a balloon as gas filled the intestines and stomach. Eventually the pressure became too great, and air escaped through a newly formed hole in the body wall weakened by decomposition. This was the hole that his hand entered before sliding into the mush that the innards had become. Truly disgusting stuff, even for my snakebite-damaged nose.
Later that night, after stopping and walking along with a half dozen live wombats, we came across more roadkill—another wombat. This one had been struck a glancing blow by a logging truck. Its neck was broken but its skull appeared intact—a perfect specimen for using in anatomy teaching. So we wrapped it up in a horse blanket. As unclotted blood was still coming out of its mouth, soaking through the blanket, we stuffed it, covered head first, into a three-gallon bucket. Upon reaching home, we put it under the house. The idea was to take it into the museum and preserve it by soaking it in 10 percent neutral buffered formalin.
The next day a big bushfire was burning in the Dandenong Ranges National Park, which is where my house in Kalorama was. Over the next two days, we were completely distracted by fire mitigation efforts, including plans for packing up the many animals. By the time we remembered the wombat, it had been under the house for three days. It was now a hairy sphere with its four legs sticking straight out. It was a methane-filled bomb that could go off with the slightest disturbance. We started driving to the same forest we had got it from, taking a new route to try and cut time, but we were soon lost. The smell was overpowering in the car as the wombat in the boot started leaking noxious gas. So we pulled over, gazing into the darkness, unable to make out where we were. All we could see was a dark slope. We assumed we were standing over some sort of ravine. So on “One, two, three!” we heaved the wombat, still cloaked in the blanket and bucket, on to the gentle slope. Late the next afternoon, a Tuesday, we went for another drive, retracing our steps. Pulling over, we discovered that the ravine was actually a slope down to the front lawn of a primary school, where we had left a child-sized object wrapped in a blanket with the head region tucked into a pale blue bucket. Oops—what must have gone through the head of the staff member who came across it first?
A much less amusing and more traumatic event occurred not long after this. My mate Tim Nias was diagnosed with leukemia, which meant that the white blood cells in his body were wiped out, just as had happened with my friend Jon from HIV/AIDS during undergraduate university. Also like him, this left Tim exposed to any bacteria that came along; however benign it might be under ordinary circumstances, it could be lethal now. As with Jon, the result was inevitable: bacteria made it into his bloodstream and killed him. Tim was one of the gentlest, funniest people I have ever had the privilege to call my friend. He was also a brilliant professional reptile keeper and absolutely gifted with venomous species in particular. He was a constant source of useful information to me. Whenever I had a tricky new animal, he was the first one I would ring for advice. His funeral in Sydney was attended by a broad spectrum of people in the reptile community, from private keepers through to the heads of the various zoological institutions. I know that Tim would have appreciated that after the service, while taking a walk in the grounds to clear my head, I caught a red-bellied black snake behind some bushes near his grave.
At this point I was maintaining a large collection of sea snakes at the Melbourne Aquarium, which had generously donated several of their very large tanks, and staff time, to help out with the research. I liked nothing more than going diving with the sea snakes with curator Diane Brandl and hand-feeding defrosted fish to the snakes. This was the most therapeutic thing I could do after Tim’s funeral and it definitely soothed my soul. As part of the research, we tested a theory that my friend and collaborator Guido Westhoff had about sea snakes: that they were able to sense water currents, which would aid their fish hunting inside the coral rubble. Guido did a series of very intricate and precise experiments, consistent with his extreme German-ness, and was able to show that sea snakes indeed had this hidden ability. Therefore, we were able to not only discover new information about the venoms, but also about the behavior of these snakes I found so fascinating.
My new venom research effort at this time was on fish venoms, a relatively neglected field. Despite the vast number of venomous fish found in the seas, streams, and lakes of the world, research into them lagged far behind research into other venomous creatures. Indeed, more papers were published in an average year on snake venom than had ever been published on fish venoms. I quickly discovered why: fish venoms are slime-filled nightmares to examine. I concluded that the lack of progress in the field was not from lack of interest, but rather due to the inherent difficulty of working with the venoms. We tried a variety of techniques to separate the venom proteins from the slime without changing the chemical properties of the toxins. After much trial and error, we settled on a combination of ammonium precipitation at refrigeration temperatures, followed by acetone:methanol precipitation at freezing temperatures. Now that we had determined a way to purify the toxic proteins, it was simply a matter of getting more raw material to work with—the fun part!
My first collection destination was Trondheim fjord in northern Norway, where I linked up with the extremely affable marine researcher Jarle Mork from the Norwegian University of Science and Technology. I arrived in peak summer, which meant endless daytime in the land of the midnight sun—my favorite time of year in Norway.
We set out on one of the marine station’s research vessels and put nets down very deep to reach the bottom, one mile below the surface. We were after a very strange fish called the havmus. A distant relative of sharks and stingrays, it had a dorsal spine over six inches long made of cartilage, not bone. Like stingrays, it was also armed with potent venom. My interest was piqued by a report in a Norwegian paper about a commercial fisherman stung by one while removing it from a net. In addition to the pain, he had wasting of the muscles in his leg and was partially crippled for weeks while the leg slowly healed.
Our first few benthic drags not only brought up abundant havmus, but also quite a large number of grenadier fish. Despite the grenadiers being a fish with a spine made of bone, and thus last sharing a common ancestor with havmus hundreds of millions of years ago, the two fish were extremely similar in appearance. This was a result of occupying the same ecological niche. Both are slow-moving predators at the bottom of the freezing cold fjords. Both have long, thin bodies that taper to a rat-like tail instead of the usual tailfin seen in fish. They look like an eel that has been decomposing on the bottom until only skeletal remains are left. They are certainly unappetizing to the eye, but both have a reputation for actually being extremely tasty, reflecting their crab-and-shrimp diet.
In two days of work, we were able to collect 110 havmus spines, which was an ample quantity to undertake the research, even taking into account the huge losses of material during the complex clean-up process. We also had a bonus come up in the nets—a halibut, quite rare in polar waters, though common in the more temperate waters further south. Global warming, with the increase in water temperatures, had extended their range.
In addition to the halibut, another unexpected but much more abundant animal came up in the nets: helmet jellyfish, usually denizens of temperate waters. I was astounded when we switched netting locations and ended up getting nothing but tons of them in the nets. This was an ecological and economic disaster unfolding before our eyes as it not only disrupted the food web, but would also ruin fisheries that had been sustainably managed for generations.
After the successful expedition to Trondheim, I stopped at the family island home on the Oslo fjord. My uncle Hans and I set out nets, this time not for venomous fish but for sea trout and flounder to eat. However, there is no escaping venom and we had several grey gurnard come up, a type of scorpionfish vital to the research. I knew all too well the power of scorpionfish venom. Before leaving Melbourne for this trip, I had been envenomated by a distantly related scorpionfish called the devilfish that my Norwegian cousin and I had collected while scuba diving in the waters at the southern tip of the Mornington Peninsula. I had been holding it in one hand while carefully raising the spines with the other hand. It gave a violent twist and kick with its tail. As it cartwheeled up into the air, knowing that an envenomation was inevitable, Haakon and I had just enough time to think the same thought: “I hope it’s not me.” But it was my forearm that it landed on, not Haakon’s, driving its venom-tipped spikes into my flesh.
Within thirty seconds, I was in so much pain that I thought I would puke. As we were in the Melbourne Aquarium at the time, we sprinted for the bathroom and turned on the hot water tap. Fish venom toxins are very large proteins that are folded back on themselves to form a loose globular structure. This means that they denature very easily, unfolding just like egg white protein does when changing from clear to opaque white in a hot frying pan. That makes first aid for fish envenomations as simple as running hot water over the affected limb. But there is one major caveat, in that the pain from the venom is much greater than the pain of scalded flesh. So, the water temperature must be tested by someone not in pain, as it was by Haakon in this instance. There have actually been cases of people presenting to hospital with a foot that has been effectively cooked. The person has generally said that there was a reduction of pain but it still hurt, so they kept it in the water, not realizing that the toxin was long gone and they were instead boiling their foot. In extreme cases, this has led to the loss of the affected limb instead of what would otherwise have been an uneventful recovery. In my case, within about two minutes the pain stopped and life returned to normal. Well, as normal as it ever got for me.
A week later, Haakon and I were off to the Osprey Reef in the Coral Sea, with Freek Vonk flying over from the Netherlands to join us. This dive spot far offshore is famous for the very large resident moray eels. These intimidating fish occupy the same niche as sea snakes, but slice fish in half with their many razor-sharp teeth. These eels have even evolved a cutting second jaw just like the monsters in the Alien movie franchise. The upper gill arch has evolved to have long, sharp, grasping teeth. The eel latches on to the hapless fish with the forward teeth and then uses the gill arch teeth to deep-throat the chunks of flesh.
Deeper still, after all the red color has been bled out of the water, were giant stingrays. Immobile discs of doom, over six feet across. They are basically biological electricity receiving stations. Even in pitch-black, they can detect another animal from up to six feet away just from the electricity put out by all living things. They are able to accurately stab with the spine a grapefruit-sized object once it comes within three feet. The disc is made of pure muscle, thus providing the leverage to propel the spine with such force that it can pierce all the way through a sternum, the protective plate where the ribs meet and which protects some particularly vital organs in the chest. The venom-tipped spines may exceed eight inches in length and many species have two of them. They are strongly backward serrated, so that they grip and tear on the way out, leaving behind one of the most painful venoms of all. The tail moves with such force that it creates cavitation like a boat propeller, moving with a speed sufficient for a vacuum to be formed behind it, creating bubbles as air boils out of the water. This was definitely my kind of dive site.
Three days before the end of the trip, Haakon and I were kicking back near the stern of the boat with Rush’s song “Tom Sawyer” pumping out a mighty bass line when a pair of giant bat-like silhouettes swam by under the boat. They could be only one thing: manta rays. We quickly grabbed our flippers, snorkels, and masks, and dived in with abandon. We stayed above them, watching them glide below us. The gliders watching the gliding. Not a care in the world. How long we watched them, I will never know. However, once they dived down out of sight, I noticed we were now a very long way away from the boat, which was now a speck on the rim of the distant horizon. Our pride would not let us signal for help by waving both arms and making an X-shape. Not that they would have been looking for us, since in our excited haste we had slipped off the back of the boat without letting anyone know we were going. The distance didn’t bother us since we were both good swimmers. The increased buoyancy afforded by salt water would facilitate a gliding freestyle stroke, so I knew my sea snake venom–destroyed shoulders would hold up. I was a bit concerned about the waves, though, as a strange, steady wind had sprung up while we were manta watching and white-capped waves were starting to build. In some cases, they were even forming surf breaks over the pinnacle reefs submerged ten feet below the surface.
About a third of the way back, I glanced down to see a fast movement. A sleek shape passed by at a high speed about fifty feet below us. Shark. About ten feet long. Big enough to do some serious damage. Not good. I wasn’t able to see the species on the first pass, but I saw it quite clearly on the second. It was a black-tipped reef shark. Not usually a dangerous species, but this was an unusually large animal, and it seemed quite agitated, as evidenced by the arched back and jutting pectoral fins. On its third pass it came right at us, turning at about a thirty-foot distance. On the fourth pass, I dived down and expelled all the air from my lungs while hitting a long metal-singer note, causing the shark to turn sharply away. When it came at us again, Haakon and I dived together and did the same, with the same happy result.
I knew that we could not keep this up indefinitely, so I told Haakon to follow me and we sprinted towards the reef breakers. My plan was that we would hide within the washing machine surge, veiling ourselves in the visual and acoustic sensory cloaking. From there we would follow the fringing reef, which made a lazy curve toward the boat, although that would increase the distance we had to cover by at least half. It was a good plan, but the irregular currents and smashing waves put tremendous strain on the rotator cuffs in my shoulders that were permanently damaged from the tearing which occurred after my sea snake bite. It took us about ninety minutes to get as close as we could to the boat, leaving a five-hundred-foot stretch of open water between it and us. By now, we could see that the crew had not spotted us—there were no heads turned our way—so they had no reason to know we were being stalked by a shark. We paused, remained motionless and scanned the water. Seeing nothing, on “One, two, three!” we sprinted toward the boat, churning the water with our strokes. By the time we got there, my shoulders felt like they were being held together by fraying rope. But even Australian Olympic legend sprint swimmer Ian Thorpe could not have beaten me in that dash!
Once we dragged ourselves onto the back deck, we could see why our absence had not been noticed. Everyone was in the cockpit, staring at the radar pattern. Over the last three hours, a cyclone had sprung up. It had already been given a name: Cyclone Larry. We were in the open ocean—a peak area for cyclone development, where matters can go from calm to chaotic in a very short period of time, particularly in midsummer. The radar was showing an ominous spiral that already had the characteristic eerily calm center. The captain was on the radio with the mainland, which was reporting back that all boats had been put on high alert and ordered back to harbor, while vessels were banned from putting out to sea. Things were now critical, since we were a long way from the coast and much closer to the cyclone. Very close, in fact. The cyclone was predicted to head in exactly the same direction as we were. We secured all loose gear, untied from the mooring and fired up all engines full for the shore. The seas grew steadily as we made our way back. All joviality was gone and all that remained was a grim sort of silent camaraderie. We reached Port Douglas late in the evening and made some phone calls to change our flights. We were able to secure seats on the first flights out the next morning.
As we drove down towards Cairns Airport, the dawn light had an eerie tinge to it. The animal life was also unsettled. The birds were aflutter, the kangaroos were bounding around randomly, and there were abundant snakes on the road. After spotting a half dozen scrub pythons, we even came across a road-killed taipan, but did not have time to stop and take a DNA sample from it. We made it to the airport with only minutes to spare to catch one of the last flights out. Landing in Melbourne, we were greeted by images on the airport’s television screens of overturned planes scattered around the runways of Cairns Airport, like the abandoned toys of a giant child. Other images showed massive damage to houses and other structures. It was rated as one of the biggest cyclones ever to have crossed the Australian coast and the biggest ever to have scored a direct hit on Cairns.
A few short months later, my phone rang. It was a reporter from The Australian, asking for a comment about Steve Irwin’s death. After a moment of stunned silence, I asked for a few more details, since this was the first I had heard of it. I learned that he had been killed by a stingray while filming at Batt Reef, dying quickly. He had approached the stingray from above and behind while snorkeling, then dived down at it. I explained that this is exactly how a tiger shark would attack a stingray in order to kill it and feast on stingray flesh. Therefore, it would trigger an instant reflexive defense from the stingray.
I knew from my recent experiense with a scorpionfish that fish venoms are extremely painful. Irwin’s last experience would have been one of sustained agony. The long barb of a giant stingray had penetrated his chest and pierced his heart. Thus, I continued, there were three possible causes of death: bleeding into the left lung; loss of blood volume; or the pressure of bleeding into the sac that surrounds the heart, which would, in effect, cause a slow-motion heart attack. The first scenario, drowning from blood in the lung, would be slower than the time he had actually taken to die and thus could be ruled out. Blood loss would be quick, as would a bleed into the pericardial sac. So it would be impossible to determine the exact cause without seeing the autopsy report or interviewing witnesses further.
Regardless, I stressed that stingrays are gentle, magnificent creatures whose venom is entirely defensive. They only sting when they feel they are in mortal danger. Their curiosity and innate intelligence make them fascinating animals to observe. The rule is: don’t mess with them and don’t invade their space. If they come up inquisitively and you remain calm, it can be one of those magical encounters. However, considering that Irwin was there to film the natural history of tiger sharks and how they predated upon stingrays, he would have known all too well the triggers that would cause a stingray to violently defend itself. One must take into account the basic premise of Irwin’s filming strategy: to provoke an animal into a defensive display so that he could scream how dangerous it was. As I had taken more than my fair share of liberties with dangerous animals in the field, as part of my generally risk-infused daily behavior, I was in no position to judge him for what could be perceived as hubris.
It was therefore quite ironic when a bit later, while netting stingrays in Moreton Bay for the fish venom research, I was stung by a very large black stingray. The barb went straight into the meaty part of my thigh, penetrating until it hit bone. When the stingray yanked the barb out, it was completely defleshed of all the venom-delivering tissue, meaning a full shot of toxins had been deposited into the jagged wound. The pain was instantaneous and blinding, and the bleeding was profuse. I knew then what hell on earth Steve Irwin’s last minutes must have been. My only conscious thought was that “stingray” was far too benign-sounding a name. Really, it should be called the “GivemeagunsoIcankillmyself-ray!”
As we were out in the ocean, hot water was not available so I had to just suffer through it and try to stem the bleeding. After three hours, the pain was bearable and the blood loss was down; by now it was just oozing out. The next concern, however, was infection. It was a puncture wound inoculated with bacteria, and the abundant fish slime left behind provided a fertile growth environment. I was on very strong broad-spectrum antibiotics for the next two weeks. My leg swelled up and got a bit red, but nothing significant. What was significant, though, was the havoc wreaked upon the muscles. The venom contained powerful myotoxins that caused muscle wasting over the next few weeks, and then, when I started working out with weights again, the calf muscle tore. It left me limping like a gang member for a couple of weeks.
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