Giant snails and tiny insects threaten the South's rice and crawfish
farms
[February 06, 2026] By
MELINA WALLING and JOSHUA A. BICKEL
KAPLAN, La. (AP) — Josh Courville has harvested crawfish his whole life,
but these days, he's finding a less welcome catch in some of the fields
he manages in southern Louisiana.
Snails. Big ones.
For every crawfish Courville dumps out of a trap, three or four snails
clang onto the boat’s metal sorting table. About the size of a baseball
when fully grown, apple snails stubbornly survive all kinds of weather
in fields, pipes and drainage ditches and can lay thousands of
bubblegum-colored eggs every month.
“It’s very disheartening," Courville said. “The most discouraging part,
actually, is not having much control over it.”
Apple snails are just one example of how invasive species can quickly
become a nightmare for farmers.
In Louisiana, where rice and crawfish are often grown together in the
same fields, there's now a second threat: tiny insects called delphacids
that can deal catastrophic damage to rice plants. Much about these
snails and insects is still a mystery, and researchers are trying to
learn more about what's fueling their spread, from farming methods and
pesticides to global shipping and extreme weather.
Experts aren’t sure what role climate change may play, but they say a
warming world generally makes it easier for pests to spread to other
parts of the country if they gain a foothold in the temperate South.
“We are going to have more bugs that are happier to live here if it
stays warmer here longer,” said Hannah Burrack, professor and chair of
the entomology department at Michigan State University.
It’s an urgent problem because in a tough market for rice, farmers who
rotate the rice and crawfish crops together need successful harvests of
both to make ends meet. And losses to pests could mean higher rice
prices for U.S. consumers, said Steve Linscombe, director of The Rice
Foundation, which does research and education outreach for the U.S. rice
industry.
Inconvenience, stress and higher costs for farmers
Courville manages fields for Christian Richard, a sixth-generation rice
farmer in Louisiana. Both started noticing apple snails after a bad
flood in 2016. Then the population ballooned.
In spring, at rice planting time, the hungry snails found a feast.
“It was like this science fiction movie,” Richard said, describing how
each snail made its own little whirlpool as it popped out of the wet
ground. “They would start on those tender rice plants, and they
destroyed a 100-acre field.”
Louisiana State University scientists estimate that about 78 square
miles (202 square kilometers) in the state are now regularly seeing
snails.
To keep the rice from becoming a snail buffet, Richard's team and many
other rice and crawfish farmers dealing with the pests start with a dry
field to give the rice plants the chance to grow a few inches and get
stronger, then flood the field after.
It's a planting method they'd already used on some fields, even before
the snails arrived. But now, with the snails, that's essentially their
only option, and it's the most expensive one.
They also can't get rid of the snails entirely. Many of the pesticides
that might work on snails can also hurt crustaceans. People directly eat
both rice and crawfish, unlike crops grown for animal feed, so there are
fewer chemicals farmers can use on them. One option some farmers are
testing, copper sulfate, can easily add thousands of dollars to an
operation's costs, Courville said.
It all means "lower production, decreased revenue from that, and
increased cost with the extra labor,” Richard said.
Cecilia Gallegos, who has worked as a crawfish harvester for the past
three years, said the snails have made her job more difficult in the
past year.
[to top of second column] |
Tyler Musgrove, a rice extension specialist with Louisiana State
University, uses a net to catch insects in a rice field Thursday,
Jan. 22, 2026, at a farm in Kaplan, La. (AP Photo/Joshua A. Bickel)
 “You give up more time," she said of
having to separate the crawfish from the snails, or occasionally
plucking them out of sacks if they roll in by mistake. Work that
already stretched as late as 3 a.m. in the busy springtime season
can now take even longer.
The snails separated from the crawfish get destroyed later.
One of the most significant pest appearances since the 1950s
To look for pests much smaller than the apple snails, entomologists
whip around heavy-duty butterfly nets and deploy Ghostbusters-style
specimen-collecting vacuums. Since last year, they've been sampling
for rice delphacids, tiny insects that pierce the rice plants, suck
out their sap and transmit a rice virus that worsens the damage.
It's worrying for Louisiana because they've seen how bad it can get
next door in Texas, where delphacids surged last year. Yields
dropped by up to 50% in what's called the ratoon crop, the second
rice crop of the year, said The Rice Foundation's Linscombe. Texas
farmers are projected to grow rice on only half the acres they did
last year, and some are worried they won't be able to get bank
loans, said Tyler Musgrove, a rice extension specialist at the
Louisiana State University AgCenter.
Musgrove said entomologists believe almost all rice fields in
Louisiana had delphacids by September and October of last year. By
then, most of the rice had already been harvested, so they're
waiting to see what happens this year.
“The rice delphacid this past year was probably one of the most
significant entomological events to occur in U.S. rice since the
‘50s when it first appeared,” Musgrove said. Delphacids had
eventually disappeared after that outbreak until now. It's been
identified in four of the six rice-producing states — Texas,
Louisiana, Arkansas and Mississippi — but it's not clear yet whether
it's made a permanent winter home in the U.S.
Scientists are still in the early stages of advising farmers on what
to do about the resurgence of the destructive bugs without adding
costly or crawfish-harming pesticides. And they're also starting to
study whether rice and crawfish grown together will see different
impacts than rice grown by itself.
“I think everyone agrees, it’s not going to be a silver bullet
approach. Like, oh, we can just breed for it or we could just spray
our way out of it,” said Adam Famoso, director of Louisiana State
University's Rice Research Station.
Climate change makes it harder to plan around pests
Burrack, of Michigan State, said that climate change is making it
harder for modeling that has helped predict how big populations of
invasive pests will get and when they may affect certain crops. And
that makes it harder for farmers to plan around them.
“From an agricultural standpoint, that’s generally what happens when
you get one of these intractable pests,” Burrack said. “People are
no longer able to produce the thing that they want to produce in the
place that they’re producing it.”
All contents © copyright 2026 Associated Press. All rights reserved |
