Dead of Night df-12 Page 16
No need to pursue that line of questioning.
“Then help us choose the best way to eliminate the parasite’s carrier host. Copepods, as I suspect you know.”
Yes, I told him, I was familiar with copepods. In fact, on the table in front of me was a thousand-milliliter flask filled with the things.
“That’s quite a coincidence,” Clark said.
Looking at the flask, I replied, “Not really. I’ve been doing a procedure your people might find interesting.”
The flask contained water that appeared murky but was, in fact, alive, animated with the tiny crustaceans. They were silt-sized, grouped as a moving gray cloud in a Pyrex container that was shaped not unlike an alchemist’s lamp.
The flask also contained guinea larvae. Which was why I was wearing surgical gloves and a face shield.
Clark said, “I have a list of pesticides. Can I read it off first?”
I was still looking at the flask. “Sure. I’ll work while we talk.”
I’d used a pipette to fill twin concave chambers in a glass microscope slide. One chamber contained a dozen swimming, darting copepods. The second indentation, only water.
The slide was mounted on the microscope’s illuminated stage. I rotated the trinocular to medium power as Clark began to read from his list of pesticides:
“We’re considering Abate, active ingredient temephos. It’s an organophosphate, the same chemical group as nerve gas. Abate inhibits neural function. Even in small amounts, it’s deadly to mosquito larvae and copepods-only an ounce or so per acre of water. But it also impacts aquatic invertebrates, and fish. It’s currently in use in many regions of the south…”
“Impact.” Add yet another euphemism for “kill.”
As he continued reading, my attention began to blur as the magnified image of a copepod came into focus.
Hello, Macro Cyclops. The copepod is named for its bright and solitary red eye. Cyclops: A micromonster that feeds on other monsters.
Its body was rocket-shaped with an elegant V-tail, and a nose tipped with oversized antenna that drooped like a handlebar mustache. Its shell, or carapace, was segmented like a lobster, but translucent so that it emitted prismatic bands of color when transected by light.
This one was female. Symmetrical egg panels were attached like fins. It added to the illusion that this was a space vehicle, not one of the earth’s most abundant life-forms.
Many people say they perceive the magnitude of the cosmos when they look at the stars. I see the same infinite complexities through a microscope’s tube, and usually in better detail.
The Leica had superb resolution, and a rheostat-controlled halogen illumination system that transformed this tiny organism into a three-dimensional animal that moved… paused… shifted directions. It appeared no less complex, nor vital, than the largest animal that has ever walked the planet.
I rotated the trinocular to its highest power, touching the fine-focus coaxial as I listened to Dr. Clark say, “… the third chemical we’re considering is Dylox, active ingredient trichlorfon, which is used to control insect pests on fruit trees and ornamentals
…”
I looked up briefly, adjusting the phone between shoulder and ear. Had I missed the second pesticide on the list? Apparently.
I leaned over the microscope once again.
The copepod’s translucent abdominal cavity now filled the lens, and I toyed with the focus as I listened to Clark. I was far more interested in this tiny crustacean, now magnified five hundred times. Because the animal’s carapace was translucent, I could look into its stomach and see that it did not contain a Dracunculiasis nymph. There was no mistaking the nymph’s bristling, dragon-toothed head.
There were bits of phytoplankton. There were fecal pellets in its lower gut. But, after spending an hour in water that contained guinea larvae, and, over a three-day period, this copepod had not fed on what should have been a preferred food source.
Amazing. Yes. I’d stumbled onto something important. Maybe. Predators that did not attack easy prey.
I no longer considered the behavior anomalous.
That’s what I’d been doing for the last few days. Selecting copepods that refused to feed on the parasites. Each time I repeated the procedure, the percentage of nonfeeders increased.
Seeing this crustacean’s empty belly pleased me. I’d seen many similar empty bellies during the course of the morning.
I shifted to low power, then used a curved probe to herd the copepod into its own personal chamber. Treated it as a hero, as I did the other nonfeeders.
After hearing Clark say, “The eighth chemical we’re considering is Dimilin, a new generation of pesticides that was developed to mimic natural-” I interrupted.
“Dr. Clark? There may be a better way to deal with this. To disrupt the parasite’s life cycle without using pesticides.”
Still sounding fatigued, Clark said, “Dr. Ford, if you have a method that doesn’t include poisoning every living creature in the Everglades, I will personally see that you get some type of medal. Even if I have to make it myself.”
The man’s field wasn’t aquaculture, but he was quick and perceptive.
I told him that the life cycle of a copepod is so brief (only a week or two) that it might be possible, through selective breeding, to quickly reshape the crustacean’s genetically coded behaviors.
“I think we can culture a hybrid copepod that doesn’t recognize guinea worm larvae as food. If the larvae’s not eaten, the parasite never matures, so it can’t reproduce. From the results I’ve been getting, I don’t think it would take us that long.”
Copepods do nothing but eat and reproduce, I explained. In a week, using only a five-gallon bucket, millions of hybrids could be raised. Make it the primary function of an aquaculture facility and billons could be hatched in a month, trillions in a year. Get the Water Management people to re-create drought conditions to reduce the number of water spaces. Hybrids would soon dominate the state’s native copepod population, passing their selected genetic traits into the future.
It wasn’t a perfect solution. The results wouldn’t be immediate. But it might reduce the parasite’s numbers steadily, maybe dramatically.
“I haven’t figured a quick way to disperse them through the water system,” I said. “That could be a problem. Massive distribution. But this could work…”
I stopped. Felt a chill because something had just popped into my mind. I did know how to find the fast way to spread parasites through the state’s water system. I’d known for days.
“Dr. Ford…? Ford? Are you there?”
I said, “Yep, I’m here-although I wonder sometimes. Dr. Clark, you’ve been talking to an imbecile. I have information you need to write down.”
I told Clark to contact the FBI immediately. Have agents check out Jobe Applebee’s elaborate diorama. Get the pumps going, then use different colored dyes to trace which miniature lakes are attached to what underground conduits, and which currents are swiftest.
I added, “Tell them to start with the two lakes where you found the guinea larvae. A drop of dye in each. I hope I’m wrong. But I don’t think I am. Track where that water goes. That’s where you’re going to find more guinea worms.”
19
LOG
17 Dec. Friday, Sunset 17:39
Planets nearing conjunction
Mercury sets: 18:41 EST
Venus: 18:52
Mars: 18:53
Jupiter: 20:32
Saturn: 21:03
Uranus: (?)
Neptune: transits 00:32
Phone interviews w/ FBI, then EPA amp; Dept. of Agri. biologists. E-mailed notes on copepod procedure to Tallahassee.
Marina Xmas party tonight.
– MDF
Friday afternoon, only two days before I was scheduled to fly to Iowa for the holidays, I went clattering down the wooden, water-slick steps of my house, rushing to get aboard the nineteen-foot Aquasport that one of the guide
s had loaned me.
I’d towed my Maverick into Fort Myers Marine to have the hull inspected. A strange feeling, being boatless.
Because I was in a hurry, I was tempted to pretend I didn’t hear when a woman’s voice called, “Hey there, Ford! Doc? I was just coming to knock on your door.”
I recognized the voice but couldn’t place it immediately. It didn’t belong to the short list of females who visit regularly. I grabbed an overhead beam to slow my momentum, turned to look, and there stood the investigator from the Bartram County Medical Examiner’s Office. Despite an intense evening together, her last name returned to memory slightly in advance of her first name.
“Graves? Ms… Graves? What are you doing on Sanibel?”
“The name’s Rona. If I split two bottles of wine with a man, I expect him to call me by my first name. Do you have a few minutes to talk? We could get some coffee.”
She was making her way along the boardwalk in the careful way of someone unsure of her footing, or unsure of the circumstances. Her facial muscles were strained-flexing, then relaxing-as if struggling to maintain a look of informal cheer.
Either that or she was dawdling. Which annoyed me. I’d just been told by a Florida Fish and Wildlife dispatcher that someone had reported seeing a big shark tangled in a net not far from Dinkin’s Bay. The shark was drowning.
I started toward the boat again. “I’d like to sit and talk but I’m right in the middle of something. An emergency. I’ve got to take off in the boat.”
“There are emergencies in the world of marine biology?”
“Nope, not usually. But this hasn’t been a normal week.”
From a wooden locker beneath the house, I took a nylon backpack already packed with medical kit, shark tags, and miscellaneous gear. I opened it and began to add gloves, prescription goggles, snorkel, my old and dependable Rocket fins, my equally old and dependable Randall survival knife.
“I know I should’ve called first. But I decided, what the hell, I’ve got the weekend off. I’ve never seen Sanibel, and you seemed like the friendly, informal type. So I… well, you’ll understand.”
I paused. There was something peculiar about her manner. “Understand what? You didn’t drive three hours just to tell me the results of Jobe Applebee’s autopsy, did you? If you did, that’s thoughtful. But it’s not like we were close-”
“No… no, that’s not the reason. We can talk later. How long do you think you’ll be gone?”
Her insistence was an additional annoyance. I looked at my watch. It was 4:13 P.M. The dispatcher told me the report had come in around four. A shark tangled in a net is likely to die. It has no swim bladder, nothing to keep it from sinking and stalling on the bottom. Minutes count. If I found the shark quickly, and if it hadn’t been too badly stressed, I might be gone an hour. If things didn’t go smoothly, I wouldn’t be back until long after dark.
She surprised me by saying, “Hey, how about I tag along? I’d like to see what a biologist does. I’m good around boats, I really am. I grew up waterskiing.”
I wasn’t wild about the idea, but I didn’t want to waste additional time debating it. I told her, “Okay. But we’re leaving now. And no guarantees about when we get back.”
She seemed weirdly relieved. People used to making decisions sometimes like it when they’re told what to do. “What’s the problem? Dealing with emergencies is one of the things I do best.”
I was already in the Aquasport, lowering the engine as she stepped aboard. “There’s a shark in trouble. It was spotted near a place called Lighthouse Point. It’s only a couple of miles from here, but we’ve gotta fly.”
“Sharks,” she said, settling herself onto the bench seat beside me. “They’ve always scared me. They’re sending you out to catch it and kill it-right?”
Locating something on water is never as easy as you hope, so I expected to have trouble finding the shark.
We didn’t.
I steered the boat beneath the causeway bridge, headed for a point of land that is the island’s last partition between bay and the open Gulf of Mexico. There’s a lighthouse there-a maritime antique-which is why the paw of beach is named Lighthouse Point.
I’d been told the shark had been spotted nearby. Luckily, though, I noticed a cluster of four or five boats off to my right, near the channel to Sanibel Marina. They were behaving oddly. The boats jockeyed for position, leapfrogging as if fishing for moving tarpon. But this wasn’t tarpon season.
To Rona I said, “Grab that stainless rail. Hang on tight,” and turned sharply, not slowing until I’d closed on the pod of boats.
It was the shark. The boats were following it, each skipper vying for a better view. Understandable. It was a very big shark that couldn’t submerge because it was tangled in a mess of ropes, plastic floats, and netting.
Beside me, Rona said, “That thing’s… alive? I thought it was a small plane at first. Like maybe it’d just crashed, and these people were trying to help. But a shark-now I see why it’s an emergency.” She turned her head, searching the empty deck. “How are you gonna do this? Do you have a gun? Or maybe a harpoon, or something?”
I’d slipped in between the boats and the fish. Looking at it, I thought about my little deformed leucas back at the lab. This was what they were coded to become: a bull shark, fully mature. It was ten or eleven feet long, and three times the girth of my chest. Probably five or six hundred pounds.
I told Rona what she was looking at, adding, “I’m going to cut it free, not kill it. What I’ve got to figure out is, how?”
The shark’s side fins, or pectorals, were each more than a yard long. They extended from its sides like wings. The top lobe of its tail, or caudal fin, was even longer, curved like a scythe. Tangled between the left pectoral fin and the tail was a section of gray monofilament netting.
The shark had probably gone after fish caught in the mesh. Not uncommon.
So the creature was now towing a thirty-foot shroud of rubbish-a clutter of buoyant floats and nylon that restricted its movement, and also kept it riding on the surface. The rope had cut so deeply into the caudal fin that I could see exposed cartilage. It made the tail stroke uneven, causing the creature to swim in wide, counterclockwise circles as it drifted with the incoming tide.
I was taking off my shirt, my glasses, stepping out of my rubber boots, in a hurry to get to work. “Consider yourself a lucky woman. In all the years I’ve dealt with bull sharks, I’ve only seen one other specimen this size. In fact…”-I considered the shark’s bulk and length; the blunt head, the density of its dark eyes, before continuing-“… in fact, this could be the same fish. It was a year or so ago; I was windsurfing. At night. I could see its outline because the water was glowing with phosphorus. It sparkled as it swam.”
It startled me, the realization. As I continued to prepare gear, I thought about it, replaying the events of that night. It was near the marina, Dinkin’s Bay. I’d never seen a specimen as large before or since. Until now.
The same animal?
Possibly. No… probably.
The unexpected connection injected a new urgency, as well as irony-ironic because this shark had attacked me. Pursued and attacked my surfboard, anyway. The only person I’d told about it was Tomlinson, who, of course, assigned the incident an exaggerated importance.
He’d used a Buddhist term that I’ve now forgotten.
Rona watched me as I picked up goggles, gloves, and bag. Her eyes went wide. “Oh no… you’ve got to be joking. Please tell me you are not going in the water.”
I said, “I’ll be fine. That shark’s the least of my worries. All these boats charging around, though, are dangerous. Were you serious when you said you knew boats? I need you to take the wheel.”
“Yes… sure. I guess so. I grew up driving ski boats.” She was studying the gauges, the throttle arm. “This is the same kind of setup?”
I was holding my fins. Should I wear them? Decided no, and dropped them on the deck.
Stepping around the console, I said, “Try to stay between me and the other boats. Mostly, keep the engine in neutral, make them avoid you.”
I slipped into the water.
The tide had put thirty yards between the shark and me. I wanted distance because I didn’t want to spook the thing.
With lungs inflated to maintain buoyancy, I drifted with the current, doing a slow sidestroke, head up, watching as the shark continued to swim in a wide, slow circle. The December water was cold, and my chest spasmed adjusting to the temperature.
I’d have no trouble catching up. But what then?
We were less than a hundred yards from shore, but close enough to the channel that there was probably ten to twenty feet of water beneath us. Because the net was tangled on the shark’s left side, the shark circled left, getting closer and closer to shore. Which was good. I wanted to end up in water shallow enough for me to stand.
I watched as the shark tried once again to turn into the tide. Its tail slapped the water feebly… strained briefly against the rope
… then slapped the surface again, its gray body contorted, pectoral fins flapping as if made of rubber.
Pathetic. Female bull sharks drop only one to thirteen pups per birth cycle, and the mortality rate is high. Only a small percentage live the dozen or so years it takes to reach sexual maturity. By examining thinly sliced cross sections of vertebrae, a shark’s age can be determined using a process similar to counting a tree’s growth rings. I once did a necropsy on a bull shark that was twenty-five years old. It was nowhere near the size of this creature.
How many decades had it swum freely? In the world of sharks, size is a valid indicator of genetic ascendancy. This animal had not only survived against great odds, it had achieved a rare degree of oceangoing invulnerability. It had outsized all enemies-only now to fall victim to a bunch of plastic trash.