“How many raptors are there?” she said. “I couldn’t tell for sure, when I saw them. I thought nine.”
“I think there’s more,” Malcolm said “I think eleven or twelve in all.”
“Twelve?” she said, glancing up at him. “On this little island?”
“Yes.”
The resin had a sharp odor, like glue. She brushed it evenly on the aluminum. “You know what I’m thinking,” she said.
“Yes,” he said. “There are too many.”
“Far too many, Ian.” She worked steadily. “It doesn’t make sense. In Africa, active predators like lions are very spread out. There’s one lion for every ten square kilometers. Sometimes every fifteen kilometers. That’s all the ecology can support. On an island like this, you should have no more than five raptors. Hold this.”
“Uh-huh. But don’t forget, the prey here is huge….Some of those animals are twenty, thirty tons.”
“I’m not convinced that’s a factor,” Sarah said, “but for the sake of argument, let’s say it is. I’ll double the estimate, and give you ten raptors for the island. But you tell me there are twelve. And there are other major predators, as well. Like the rexes…”
“Yes. There are.”
“That’s too many, she said, shaking her head.
“The animals are pretty dense here,” Malcolm said.
“Not dense enough,” she said. “In general, predator studies – whether tigers in India, or lions in Africa – all seem to show that you can support one predator for every two hundred prey animals. That means to support twenty-five predators here, you need at least five thousand prey on this island. Do you have anything like that?”
“No.”
“How many animals in total do you think are here?”
He shrugged. “A couple of hundred. Maybe five hundred at most.”
“So you’re off by an order of magnitude, Ian. Hold this, and I’ll get the lamp.”
She swung the heat lamp over the baby, to harden the resin. She adjusted the oxygen mask over the baby’s snout.
“The island can’t support all those predators,” she said. “And yet they’re here.”
He said, “What could explain it?”
She shook her head. “There has to be a food source that we don’t know about.”
“You mean, an artificial source?” he said. “I don’t think there is one.”
“No,” she said. “Artificial food sources make animals tame. And these animals aren’t tame. The only other possibility I can think of is that there’s a differential death rate among prey. If they grow very fast, or die young, then that might represent a larger food supply than expected.”
Malcolm said, “I’ve noticed, the largest animals seem small. It’s as if they don’t seem to reach maturity. Maybe they’re being killed off early.”
“Maybe,” she said. “But if there’s a differential death rate large enough to support this population, you should see evidence of carcasses, and lots of skeletons of dead animals. Have you seen that?”
Malcolm shook his head. “No. In fact, now that you mention it, I haven’t seen any skeletons at all.”
“Me neither.” She pushed the light away. “There’s something funny about this island, Ian.”
“I know,” Malcolm said.
“You do?”
“Yes,” he said. “I’ve suspected it from the beginning.”
Thunder rumbled. From the high hide, the plain below them was dark and silent, except for the distant snarling of the raptors. “Maybe we should go back,” Eddie said anxiously.
“Why?” Levine said. Levine had switched to his night-vision glasses, pleased with himself that he had thought to bring them. Through the goggles, the world was shades of pale green. He clearly saw the raptors at the kill site, the tall grass trampled and bloody all around. The carcass was long since finished, though they could still hear the cracking of bones as the animals gnawed on them.
“I just think,” Eddie said, “that now that it’s night, we’d be safer in the trailer.”
“Why?” Levine said.
“Well, it’s reinforced, it’s strong, and very safe. It has everything that we need. I just think we should be there. I mean, you’re not planning on staying out here all night, are you?”
“No,” Levine said. “What do you think I am, a fanatic?” Eddie grunted.
“But let’s stay for a while longer,” Levine said.