He added, “I can’t think of a faster way to spread a disease vector around the globe. Introduce it at Disney.” I heard papers rattle. He was resuming his role as interviewer. “Now you know the facts, Dr. Ford. Would you mind answering our questionnaire?”
He had a written list. It was bureaucracy-think: Poll the experts, and the consensus provided an effective scapegoat for a department burdened with making a tough decision.
Clark’s questions were linked to a more basic question: What is the most effective way to eradicate a species of waterborne parasite without destroying other plants and animals?
I was sitting at a table, my Leica microscope within easy reach. I told him, “The first thing I’d do is contact South Florida Water Management and tell them not to release water from Lake Okeechobee into the ’Glades. Create an artificial drought. Slow the flow of water. That might buy some time.”
Clark said they’d already done that. His questionnaire was based on a worst-case scenario: What if the parasite was already widely dispersed?
“We’ve been discussing two options,” he said. “Introduce a fish or insect from Africa that preys naturally on guinea worm larvae. Or interrupt the parasite’s life cycle by eliminating its requisite host.”
I’d told him that I had a philosophical problem with importing one exotic to control another. Ecosystems take thousands of years to balance interlinkings between geography and species. The resulting milieu is not a stage for experimentation. Tinkering is a recipe for disaster that’s been demonstrated too many times.
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 & 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 guides 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.