done.” They had to coax him not to quit. Another
time, he tripped and fell while running from a
rampaging elephant. “I was certain I was going
to die,” he told me. Seeing him lying still, the
elephant turned away.
Dimoto’s observations are the continuation
of a study that a primatologist named Caroline
Tutin began in 1984, when she and her col-
leagues established a research station that’s
still operating inside the park. They wanted
to understand how seasonal variations in the
amount of fruit affected gorillas and chimpan-
zees. Tutin’s research ended in the early 2000s,
but the monthly monitoring of hundreds of trees
marked with metal tags bearing unique numbers
went on, making it the longest continuous study
of its kind in Africa.STARTING IN 20 16, Emma Bush, a colleague of
Whytock’s at the University of Stirling, began
analyzing these data. She found a dramatic
decline in the amount of fruit. On average, the
probability of encountering ripe fruit for 73 tree
species that were monitored had decreased by
81 percent from 1987 to 2018. If elephants had
to search 10 trees in 1987 to find one with ripe
fruit, they now had to search more than 50 trees.
Bush had a clue about why this could be
happening. In the 1990s Tutin had observed a
decline in the flowering and fruiting of certain
tree species during years that were hotter than
usual. She hypothesized that the nighttime
temperature had to drop below about 66 degrees
Fahrenheit for these trees to flower.
Examining Lopé’s weather data for the pre-
vious three decades, Bush and her colleagues
found that the average nighttime temperature
had gone up by about 1.5 degrees. The amount of
rainfall also had decreased significantly. Climate
change was making Lopé hotter and drier.
“We think this is the most credible theory as
to why fruit has been declining,” Bush says.
After Bush shared her results with Whytock,
the two discussed how to figure out whether
this was affecting the park’s wildlife. Whytock
had just started a project to assess biodiversity
in Lopé using hundreds of camera traps. He
also had seen recent images of elephants from
camera traps that Anabelle Cardoso of Oxford
University had set up for her research.
Many of those elephants looked alarmingly
emaciated. In some images, their ribs were
clearly visible. Whytock recalled photos from
the early 1990s, in which the elephants had
plump bellies and ample behinds. The contrast
was shocking.
Looking for old images of elephants, Whytock
turned to Lee White, a biologist who is Gabon’s
minister of water, forests, the sea, and the envi-
ronment. In the late 1990s, while doing research
at Lopé, White had recorded hundreds of vid-
eos of elephants on his camcorder. “And he had
kept all the tapes—literally hundreds of tapes,”
Whytock says. “I was handed this enormousTHE BODY CONDITION
OF FOREST ELEPHANTS
DECLINED FROM 2008
TO 2018. THE SCARCITY
OF FRUIT WAS THE
LIKELIEST EXPLANATION.A FRAGILE REFUGE FOR FOREST ELEPHANTS 115