Feral hog invasions leave coastal marshes less resilient to climate change
Coastal marshes that have been invaded by feral hogs recover from natural disasters up to three times slower, and are significantly less resilient to climate change, according to a recent study from Duke University and the University of Massachusetts Boston.
Feral hogs invade marshes to eat ribbed mussels, a shellfish species that plays a vital role in the resiliency of marshes by creating healthy areas for marsh plants to live.
"[Saltmarshes are] really considered the Superman of marine ecosystems in that they are incredibly resilient," said Brian Silliman, a professor of marine conservation biology at Duke and study co-author. "The key to this superpower are the [ribbed] mussels. So the hogs are acting like the Kryptonite here because they're taking away that superpower."
Silliman's research suggests that marshes disturbed by hogs can take an extra 80 to 100 years to recover when hit by a natural disaster, like a drought. There's also a possibility that disturbed marshes may never recover from disasters.
Coastal marshes along North Carolina provide valuable economic and environmental benefits.
"Marshes act as natural seawalls, dampening and baffling incoming waves, as well as reducing storm surge and flooding," said Silliman. "They're [also] incredible pollution sponges. They soak up the carbon from the atmosphere."
One way to help marshes is to decrease the population of feral hogs, which has grown dramatically across the United States over the past few decades. More than 6 million hogs are estimated to be in the United States, mostly concentrated in the south and west.
In Sampson County, frequent hog sightings led government groups to launch a pilot project this year to tackle the problem in the area. North Carolina law classifies hogs as nongame animals, meaning they can be hunted without limits throughout the year.
"It's already decided that we need to control their population numbers," Silliman said. "We either have to increase our hunting pressure or think about other ways that we can control their population, [like] by reintroducing or facilitating predators in the area."