May 2008 — Over a decade of work and
contributions by more than 200 leading conservation scientists have
produced a first-ever comprehensive map and database of the diversity
of life in the world’s freshwater ecosystems. The map and associated
fish data – a collaborative project between World Wildlife Fund and The
Nature Conservancy — are featured in the May issue of the journal
Freshwater Ecoregions of the World divides the world’s freshwater
systems into 426 distinct conservation units, many of which are rich in
species but under increasing pressure from human population growth,
rising water use, and habitat alteration.
Among the highlights:
- This is the first study to compile data on freshwater
species — including fish, amphibians, crocodiles and turtles — for
nearly all of the world’s inland water habitats
18,000 species have been mapped and placed into freshwater ecoregions.*
This species list includes 13,400 fish, 4,000 amphibians, 300 turtles,
and 20 crocodile species and their relatives.
- About half of all freshwater fish are endemic, or found in only one ecoregion.
of major rivers such as the Amazon, Congo, Ganges, Yangtze, and the
rivers and streams of the American Southeast were identified as
outstanding for rich fish populations and high endemism (species found
- In addition, several smaller systems that
had not been identified in previous global assessments, such as Congo’s
Malebo Pool, the Amazon’s western piedmont, and Cuba and Hispaniola,
were determined to have high numbers of endemic fish species.
water use for agriculture, industry, drinking and livestock are placing
freshwater ecosystems in 55 ecoregions under high stress, threatening
the species and habitats.
- In another 59 ecoregions more
than 50 percent of their area has already been converted from natural
habitats to cropland and urban areas.
“Freshwater ecosystems are the least studied parts of our natural
world – they are like vast unexplored libraries, brimming with
information,” said World Wildlife Fund’s Robin Abell, who headed the
study. “Freshwater Ecoregions of the World allows scientists and
non-scientists alike to gain a better understanding of this world and
help guide efforts to save these systems and species before they are
Freshwater habitats support more than 100,000 species and provide
humans with critical services such as drinking water and fisheries. Yet
freshwater habitats and species are among the most imperiled in the
world and have often been left out of large-scale conservation planning.
Until now there were no data on global freshwater biodiversity
synthesized in a way that was useful to conservation. Collected
research tended to focus only on major rivers or select hotspots,
leaving out many other freshwater systems. Plus, information was not
easy to access and search. As a result, it has been difficult to gain a
truly comprehensive understanding of patterns of freshwater
biodiversity across the globe.
The Freshwater Ecoregions of the World (FEOW) project was created to
address this need. This extensive and easily searchable resource now
provides access to information that can help ensure freshwater systems
are well understood, promoted and protected.
The Nature Conservancy’s Carmen Revenga said Freshwater Ecoregions
of the World could not have come at a more important time as
competition for freshwater resources increases around the world. “Our
lack of knowledge of freshwater species has hindered our efforts to
conserve rivers, lakes and wetlands around the world. Simply having a
map that shows areas rich in freshwater species will help us set
conservation priorities and begin to put a face to these unique and
essential species, which work to keep our freshwater ecosystems alive
The comprehensive map and database (http://www.feow.org) are vital tools for conservationists trying to save the world’s freshwater ecosystems.
*A freshwater ecoregion is a large area encompassing one or more
freshwater systems that contains a distinct assemblage of natural
freshwater communities and species. The freshwater species, dynamics,
and environmental conditions within a given ecoregion are more similar
to each other than to those of surrounding ecoregions and together form
a conservation unit.
Source : World Wildlife Fund