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A28 SCIENCE
Wednesday 6 november 2019
Bringing the world's buried wetlands back from the dead

By MATTHEW BROWN and onflies, damselflies. ... You can trigger drought, lead- two more ducks, then two berm across a low area in
JAMES BROOKS can't really beat a pond." ing to more pumping of more and so on to the ho- different field to create a
Associated Press But the battle for the wet- water reserves that would rizon. small pond.
HINDOLVESTON, England lands is a struggle. While ef- otherwise feed surface But to farmers, these wet- The guiding principle is to
(AP) — The ghosts are all forts are under way to stem wetlands, scientists say. lands carved into the earth have "no net loss" of U.S.
around the gently rolling losses and regain some of "We now know the value by glaciers some 10,000 wetlands. A similar tactic
farmlands of eastern Eng- what's been lost, wetlands of wetlands, and we know years ago can be an ad- has been adopted in Chi-
land. But you have to know around the world continue with increasing precision versary. They bog down na.
where to look. to be filled in and plowed how many wetlands we're tractors and can kill young Yet in both nations, scien-
These are not the kind of tists are concerned that
phantoms that scare or the approach papers over
haunt — they are ghost significant differences be-
ponds. Over the years, tween natural wetlands
landowners buried them, and those created by hu-
filling in wetlands so they mans. That's because con-
had more land for planting structing ponds or reser-
crops and other needs, or voirs with water year-round
let their ponds fade away doesn't fulfill the same eco-
with neglect. Along with logical role as the smaller
those ponds, they erased wetlands they replace.
entire ecosystems — and "People brag about the
contributed to the decline fact that there's been no
of wetlands worldwide. net loss. But what they've
The result: an array of en- done is destroy natural wet-
vironmental calamities, lands and created artificial
ranging from rising floods ones," says Stuart Pimm, a
to species hurdling toward Duke University professor.
extinction. ___
There are some who are Since the start of the 20th
trying to reclaim these lost century, 75% of the United
waterbodies. In eastern Kingdom's ponds have
England, a motley team of been lost.
farmers, university research- Brad Sands surveys his cattle on a restored wetland and grassland project near Ellendale, N.D., Nick Anema describes how
ers and conservationists is on Thursday, June 20, 2019. his view of farming differs
digging into the region's Associated Press markedly from his father's,
barley and wheat fields to who regarded the natural
turn back the clock. over. losing. The next step is for crops, leaving patches of world as an obstacle to
With chain saws, an exca- ___ the governments to act," lifeless stalks. overcome. For Nick Ane-
vator and plenty of sweat, Almost 90% of the world's says Royal Gardner, direc- Some farmers steer around ma, farming and preserva-
it takes just a few hours to wetlands disappeared tor of the Institute for Bio- them, planting in swirling tion are inextricably linked.
resurrect one dying pond over the past three cen- diversity Law and Policy at patterns to avoid wet ar- In 2013, he saw an adver-
near Hindolveston, a thou- turies, according to the Stetson University in Florida. eas. Other times, the wet- tisement seeking farmers
sand-year-old village not Ramsar Convention, an or- ___ lands are removed, often who would be willing to
far from the North Sea. They ganization formed around A few hours of heavy rain to make way for corn. have ghost ponds on their
fell trees and shrubs, then a 1971 treaty to protect in North Dakota are all it Despite their mind-bog- property excavated as
start digging until reaching wetlands. And the losses takes to transform the dry, gling numbers — several part of a research project.
their goal: an ancient pond have accelerated since cracked earth of the prairie million potholes are spread He suspected a low point in
bottom that once support- the 1970s. into thousands upon thou- across a region that cov- one of this fields fit the de-
ed insects, aquatic plants The consequences are sands of pocket-sized wet- ers portions of five states scription of a ghost pond
and the birds and animals profound — wetland-de- lands. and three Canadian prov- and a check of old maps
that feed on them. pendent species threat- The rain pools in shallow inces— these wetlands confirmed it. By the time
"As soon as they get water ened with extinction, more depressions known as prai- are steadily blinking out. the excavation wrapped
and light, they just spring severe flooding and the rie potholes and quickly One by one, they're being up, water already was
to life," says Nick Anema, release of huge amounts flushes out insects from be- drained or plowed under. pooling at the bottom.
a farmer in nearby Dere- of the greenhouse gas car- neath the soil. Only human-made wet- After ghost ponds are dug
ham who has restored bon dioxide. Each pothole becomes a lands buck the trend to- out, seeds from long-bur-
seven ponds on his prop- Climate change threatens haven for a pair of ducks. ward global decline. Rice ied water plants come to
erty. "You've got frogs and to worsen the problem. Two blue-winged teals paddies, reservoirs and life, including in one case
toads and newts, all the Warmer temperatures and dabble on one pothole. agricultural stock ponds all a pond on Anema's farm
insects like mayflies, drag- changing rainfall patterns On the next pothole are increased in acreage since that had been filled in an
the 1970s, according to estimated 150 years ago.
Ramsar. And as the plants come
Barton Schott, a third- back, so do the insects that
generation farmer in the depend on them, followed
small community of Kulm, by fish and birds that eat
North Dakota, recently in- the insects.
stalled networks of perfo- "They've done just what we
rated pipes beneath some hoped," says Carl Sayer,
of his fields to drain off the a researcher at University
standing water. He must College London. "They're
offset the losses under fed- wonderful, healthy, vibrant
eral regulations, installing a ponds,"q