st Tutilo Mudumba and
affers from the Uganda
-drive vehicles. Their
wire traps intended to kill
urchison Falls National
rs set more illegal snares
here else in the world.
buffalo, or warthogs for
animals also stumble
are among the poorest in
by impoverished locals
ographic explorer,
ions in the park as the
nprofit engages commu-
nares into intricate
on to learning skills as
e that allows them to
ic needs such as medi-
es but also empowering
employs some 600 arti-
culptures each month,
d States. —JANI HALLRAP
SURE
RUTH MBABAZISNAGGING SNARES
During one five-hour search, a team can collect about
200 traps, which local artisans craft into sculptures of giraffes,
hippos, and other wildlife that populate the park.THREEGORGES
DAMFree-flowing
Human impactedObYeni
seyAmazonCongoYangtzeAmur
Ye
llowLen
aNi
leMississippiObYeni
seyYeni
seyYeni
seyAAAmmmaaazzzooonnnCCCooonnngggoooYYYaaannngggtttzzzeeeAAAmmmuuurrr
Ye
llow
Ye
llow
Ye
llowLen
aLen
aLen
aNi
leNi
leNi
leMississippiMississippiMississippiNORTHNORTHAMERICAAMERICAAMERICAAFRICAASIASOUTHGORGESTHREE
DAMEXPLORE | ATLASSETTING
RIVERS FREE
BY HEATHER GABRIEL SMITH AND CHRISTINA SHINTANILONG, FREE-FLOWING RIVERS are
increasingly rare. These serpentine
giants should support entire ecosystems
and allow the unobstructed movement
of energy, materials, and wildlife in their
waters and in the surrounding land-
scape. But humans have been harness-
ing their immense power for centuries,
building so many dams and reservoirs,
and so much other infrastructure, that
now only 37 percent of the world’s riversover a thousand kilometers long (621
miles) still run free. Human impacts
include dams trapping sediment so
that it can no longer naturally shape
the river and deltas, and regulation of
reservoir water levels to reduce flow to
a trickle in some areas. Just how much
these obstructions disrupt connectivity
can vary throughout a river, but under-
standing their many consequences is
crucial to restoring these ecosystems.28 NATIONAL GEOGRAPHIC