Body of the article
Hurricane Maria devastated Puerto Rico. Thousands of people died in the 2017 storm — the most destructive in Puerto Rico’s recent history and the third-deadliest in U.S. history after Hurricanes Katrina and Harvey. Hurricane Maria also left at least one species, the Puerto Rican pigeon, on the brink of extinction. Now, Frank Rivera-Milán, an ecologist with the US Fish and Wildlife Service, warns that if another Maria-sized storm hits the island within the decade, the common dove will be gone forever.
Rivera-Milán has been monitoring the critically endangered Puerto Rican pigeon since 1986. During that time, three major hurricanes have struck the island. Category 4 Hurricane Hugo in 1989 caused pigeon numbers to decline, but they returned to pre-hurricane levels within two years. The birds sailed largely unscathed through Hurricane Georges, a Category 3 storm in 1998, but Maria was different.
Before Maria struck, Rivera-Milán watchdogs estimated that there were about 12,000 pigeons throughout Puerto Rico. The year after the storm, the population had dropped to just 750, according to surveys. In the island’s east-central region, where the pigeon was historically most common, population densities dropped from about four per square kilometer to just 0.5. Since then, numbers have remained low, leaving the bird in a precarious position.
Hurricanes are part of life in the Caribbean. On average, seven storms, including three major hurricanes, strike the region each year. Life usually recovers, but climate change makes hurricanes stronger. The Puerto Rican pigeon isn’t the only species suffering.
Recent research on Sint Eustatius, an island in the northeast Caribbean, shows how the intense 2017 hurricane season dramatically reduced populations of an endangered iguana. Similarly, a two-decade study of West Indian woodpeckers in the Bahamas concludes that while the birds are resilient to hurricanes, increasingly violent storms could test their survivability.
Michael Akresh, an ecologist at Antioch University New England in New Hampshire who led the woodpecker study, says that along with stronger hurricanes, other threats like hunting and introduced predators make populations much more vulnerable.
Joseph Wunderle, a wildlife biologist at the International Institute of Tropical Forestry in Puerto Rico, agrees, adding that many habitats have also been lost. The resulting patchy habitats and small, dispersed populations are more at risk from disturbances such as hurricanes.
Because strong storms that flatten trees destroy their food, the bird species most threatened by hurricanes are fruit and seed feeders such as the dove and nectareaters. (Maria killed twice as many trees as Hugo and Georges.) In contrast, Wunderle says, “birds, which feed mostly on insects and maybe small frogs and lizards, seem to get through [hurricanes] pretty good.”
Pigeons are also susceptible as they only lay one egg at a time. Most pigeons lay two, Wunderle says, while other birds lay more. This complicates recovery for the plain dove because “you don’t produce as many babies,” he says.
If the common dove is wiped out by a hurricane, it won’t be the first in recent history. According to Akresh, that’s probably what happened with the Bahama nuthatch. The bird was only found in Grand Bahama before Category 5 Hurricane Dorian struck in 2019, destroying the pine forests where it lived.
“Nobody’s seen the Bahama nuthatch in the last two or three years…so this bird may have gone extinct,” says Akresh.
Wunderle believes that habitat restoration is key to supporting Caribbean birds. The primary goal of recovery efforts, he says, should be to rebuild lowland forest ecosystems that have been lost to agriculture, since these habitats recover from hurricanes much faster than forests at higher elevations. Another conservation effort could be to encourage the growth of trees that are more resilient in the face of storms, such as B. Palm trees. Akresh adds that conservation strategies like captive breeding and removing predators would also help endangered species like the common pigeon.
