It happened a little before 2 p.m. Primate keeper K.C. Braesch was standing just a few feet away when Iris emitted a loud, guttural cry, known to scientists as belch-vocalizing. Iris then scrambled to the top of her enclosure.
Braesch stepped back and scanned the enclosure to see what might have agitated the ape. Was it Kiko, the male? Although generally a lump, Kiko can turn into a hothead and throw things. But no, Kiko was lounging.
Then — all this had happened within about five seconds — Braesch felt the earthquake.
“Animals seem to know,” she said Wednesday. “You always hear it anecdotally, but this is the first time I’ve seen it.”
Orangutans, gorillas, flamingos and red-ruffed lemurs acted strangely before humans detected the historic magnitude-5.8 earthquake. Now the question hovering over the zoo is: What did the animals know, and when did they know it?
Therein lies a scientific mystery, one in which hard facts and solid observations are entangled with lore and legend. There has been talk over the years about mysterious electromagnetic fields generated by rupturing faults. There has been speculation about sounds inaudible to humans, and subtle tilting in rock formations, and the release of vapors that people can’t smell.
But there also may be less to the mystery than meets the eye, with Tuesday’s zoo weirdness merely serving as a reminder that many wild animals are paying close attention to nature while humans are doing whatever it is that humans do.
The zoo documented a broad range of animal behavior before, during and after the tremor that began in central Virginia and shook much of the eastern United States. For example, a gorilla, Mandara, shrieked and grabbed her baby, Kibibi, racing to the top of a climbing structure just seconds before the ground began to shake dramatically. Two other apes — an orangutan, Kyle, and a gorilla, Kojo — already had dropped their food and skedaddled to higher turf.
The 64 flamingos seemed to sense the tumult a number of seconds in advance as well, clustering together in a nervous huddle before the quake hit. One of the zoo’s elephants made a low-pitched noise as if to communicate with two other elephants.
And red-ruffed lemurs emitted an alarm cry a full 15 minutes before the temblor, the zoo said.
During the quake, the zoo grounds were filled with howls and cries. The snakes, normally inert in the middle of the day, writhed and slithered. Beavers stood on their hind legs and then jumped into a pond. Murphy the Komodo dragon ran for cover. Lions resting outside suddenly stood up and stared at their building as the walls shook.
Damai, a Sumatran tiger, leaped as if startled but quickly settled down. Some animals remained agitated for the rest of the day, wouldn’t eat and didn’t go to sleep on their usual schedule.