The World's Forgotten Fishes - 38

8. FRESHWATER FISH IN FREEFALL
Figure 6: Of the 10,336 (56%)
freshwater fishes whose conservation
status has been assessed by
IUCN, 30% are considered at
risk of extinction.

ARE
CONSIDERED
AT RISK OF
EXTINCTION.

Nowhere is the world's biodiversity
crisis more acute than in freshwater
ecosystems. Around a third of
freshwater fish species are threatened
with extinction61, and 80 species
have already been declared Extinct.
Populations of migratory fishes - the
travellers of the freshwater world,
including sturgeon, salmon, hilsa and
gilded catfish - have fallen by 76 per
cent since 1970 62 . And populations
of large iconic fish, the titans of the
freshwater world, like the beluga
sturgeon and the Mekong giant catfish,
have been hit particularly hard,

declining by a catastrophic 94 per cent
since 1970 63.
The reasons for such precipitous falls
are not hard to identify when we look at
what's happening to the world's rivers,
lakes and wetlands:
* Treating freshwater ecosystems
as wasted space: Undervaluing
the diverse benefits of healthy
freshwater ecosystems and their
riparian habitats paves the way for
them to be dammed, drained, dredged,
damaged and converted into farmland
or paved over - wrecking the habitat
of freshwater fishes in the process.
For example, floodplains, continue
to be disconnected from their rivers
and built upon, not only destroying
essential fish spawning habitat but also
increasing the risk of flooding. Around
35 per cent of wetlands have been
lost in the past 50 years64 and the rate
shows no signs of abating.
* Unnatural river flows: Decisions
about water flows related to
hydropower, dams and abstraction
are still driven by human needs rather
than environmental ones, impacting
fishes that have evolved their lifecycles
in relation to the seasonal changes
in the timing and quantity of flows,
including natural flood pulses.

STURGEON: WORLD'S MOST THREATENED FAMILY OF FRESHWATER FISHES
These gentle giants have been around since the age of the dinosaurs, but 23 of the 27
species are now threatened with extinction due to hydropower dams blocking their
migration routes along the Yangtze, Danube, Rhine and other rivers, overfishing,
poaching for the illegal wild caviar trade, pollution and habitat loss. Indeed, the Chinese
paddlefish was declared extinct in 2020. Ongoing developments, including navigation
projects, dredging activities and hydropower dams, are increasing the pressure on
sturgeon populations in Europe, many of which already depend on reintroduction
programmes as a last glimmer of hope.

For hundreds of years, sturgeon have played a major role in local economies, providing
food and livelihoods for many - chronicles from the 11th century mention that beluga
sturgeon were used to feed hungry troops marching along the Upper Danube. A beluga
sturgeon measuring 7.2m was once caught in the Volga river, but few giants are spotted
these days. Indeed, few sturgeon of any size are seen in the wild these days. WWF has
set up a new global initiative to safeguard these ancient creatures. Hopefully, it will
ensure that no sturgeon species follow the Chinese paddlefish to extinction. Because if
we can save sturgeons, we will save so much more - helping to revive the rivers they live
in for the benefit of people and nature.

The World's Forgotten Fishes page 38

* Chopped up rivers: Millions
of existing barriers from mega-dams
to small dams, weirs and culverts
fragment rivers across the world,
blocking fish migration and disrupting
the flow of water, sediments and
nutrients. In Europe alone, there are
an estimated 1 million river barriers -
at least 100,000 of which are
obsolete65. And more are yet to come.
Thousands of new hydropower dams
are on the drawing board across
the world from the Amazon to the
Zambezi, including hundreds in
protected areas. Only 1/3rd of long
rivers are still free flowing66 and
many of these are threatened by
proposed hydropower projects, as are
many of the shorter wild rivers
in regions like the Balkans and
the Himalayas.

The World's Forgotten Fishes

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