In October 2017, Hurricane Maria tore through the forests of Puerto Rico. The immediate effects were widespread. Such powerful storms are projected to become more frequent in the tropics and subtropics as climate warms, so long-term changes could be in store as well. Three months after the storm, a team led by Columbia University forest ecologist Maria Uriarte began investigating. (All photos: Kevin Krajick) READ THE FULL SCIENTIFIC STORY
Before the hurricane, this high-elevation plot in Toro Negro state forest was a shady, cathedral-like space, roofed in by leafy canopy. Fierce winds took off the tops off most trees. Forest ecologist Maria Uriarte (right) records damage, tree by tree.
Many trees were torn from the ground; big, tall ones were especially vulnerable. These fallen pines, planted decades ago, are not native to the island, and fared worse than local species.
Some trees were snapped in half, knocking down whatever others they struck.
A high-elevation site in Carite state forest, in the eastern part of the island, suffered badly.
To tally damage, PhD. student Andrew Quebbeman counts missing branches on previously cataloged individual trees at El Toro.
PhD. student Jazlynn Hall inspects a surviving tree. The metal spring around the trunk is a dendrometer, previously installed to record growth over months or years.
The team records data on literally thousands of individual trees. Putting together all the data, “you start to form a picture of how these forests might develop in the future,” says Uriarte.
Entrance to a recreation area in Carite state park, abandoned since the hurricane.
Former pathway to a popular swimming hole at Carite.
Falling trees wreaked havoc everywhere. Every shelter in this public picnic area near the village of Cayey was squashed.
Power lines like these in the mountain town of Pica were hit hard by wind and toppling trees. 100 percent of the Puerto Rico was without electricity following the hurricane; three months later, nearly half the island was still cut off.
Concrete utility poles at Toro Negro state park snapped, same as those made of wood. Ones made of metal also were thrown down in many places.
Ezequiel Godina Luna, a utility worker from Texas, was one of thousands of skilled technicians imported to bring the grid back. Recently, many of these workers were sent home, even though much of the island still remains without power.
Forests are regenerating from the ground up. Tree seedlings sprout from the newly sunlit floor of Toro Negro.
Reaching for the sky, a largely branchless alchornea tree sprouts a vertical lawn of new foliage; some of these leaves will probably turn into branches, if the tree survives.
Epiphytes (plants that grow on trees or other plants) are an important part of the ecosystem in much of the island. These ones appear to be energized by the newly sunny landscape.
Other creatures may be jeopardized. Anole lizards, normally camouflaged by wall-to-wall foliage, have been suddenly exposed to hawks and other predators.
Virtually all of Puerto Rico’s forests have sprung up on former crop or grazing land, and are still heavily influenced by humans and their livestock. This stray horse was wandering around Guilarte state forest.
Much of Puerto Rico’s drinking water comes from rainfall originating in forests, channeled through streams and lakes. The hurricane destroyed much water infrastructure and caused massive soil erosion. Tap water is still unsafe to drink in many areas, or just simply unavailable.
On the up side, masses of fallen branches provide a burst of nutrients to the forest floor, along with habitat for diverse creatures from fungi to spiders. Grizelle Gonzalez, an ecologist with the U.S. Forest Service, checks out a debris pile at El Yunque National Forest.
Uriarte goes over remote imagery at El Yunque’s research station. Her study will combine images from satellites and aircraft with meticulous ground observations to come up with a comprehensive picture of hurricane damage.
El Yunque is a locus of long-term research on all kinds of forest processes that will help inform Uriarte’s work. A team headed by Omar Gutierrez del Arroyo of the University of California, Berkeley, (right) samples forest soil, which will be analyzed for bacterial activity.
High in a weather-observation tower at El Yunque, University of Puerto Rico technician John Bithorn collects rainwater for chemical analysis. As climate warms, precipitation patterns are expected to shift substantially, affecting crops, forests and water supplies.
Like the forests, Puerto Ricans are bouncing back. At a popular coffee stand in the town of Adjuntas, the barrista’s partly obscured t-shirt reads (translated to English): In Puerto Rico, The Lights Aren’t Out—Our Light Is Stronger!
After a mercifully gentle rainstorm, the suburbs of San Juan can be seen beyond recovering forest at El Yunque.
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