09 May 2006 - Santiago
de Cali, Colombia — South American scientists
are about to embark on an expedition through the
Amazon and Orinoco Rivers to survey freshwater
dolphins.
The expedition, which consists
of scientists from Colombia, Peru, Ecuador, Bolivia
and Venezuela, will start in the Venezuelan city
of Ciudad Bolivar and continue 1,730km to Puerto
Carreño in Colombia.
"Freshwater dolphins are
one of the most endangered mammals in the world,"
explained Fernando Trujillo, director of the Fundación
Omacha, one of the organizations leading the expedition,
with support from WWF, the Wildlife Conservation
Society, Fundación La Salle and the Whale
and Dolphin Conservation Society.
"Mercury contamination,
deforestation, indiscriminate capture and incidental
fishing are some of the factors affecting the
species. Currently we don’t have abundant populations
and this census will allow us to gather data in
order to design a management and monitoring plan
as well as get to know the state of the watersheds
of the Amazon and Orinoco Rivers."
This is the first dolphin counting
initiative in South America and it follows similar
counts in Asia where WWF has financed research
trips in India, Pakistan and Bangladesh. The idea
is to establish how many river dolphins there
are in the Amazon and Orinoco in order to set
up specific conservation strategies. The census
is also part of a training programme for South
American scientists in estimating the number of
threatened species.
"Supporting this census
is important for WWF since the conservation of
the pink river dolphin is a good indicator of
the ecological health of these river basins,"
explained Saulo Usma , WWF-Colombia’s Freshwater
Coordinator. "Being a regional initiative,
the information gathered will help achieve the
conservation goals of our global freshwater and
species programmes."
The pink river dolphin (Inia
geoffrensis), also known as the boto, is found
in lowland fast flowing, whitewater rivers, clearwater
or blackwater rivers. The species is also present
in the largest tributaries, lakes, confluences
and seasonally flooded forests. It depends on
healthy fish populations for its survival. Historically,
the boto has been spared human persecution because
of the belief that it has special powers. Today
however, it is increasingly viewed by fishermen
as an unwanted competitor for fish. The boto can
also get tangled up in fishing nets, or suffer
wounds by colliding with boats. To date, no major
reduction of their range has been observed.
"Counting dolphins is complicated,
since they spend most of their time underwater,"
added Trujillo.
"If the researchers move slowly, the dolphins
can overtake the boat and be recounted. We have
designed a technique in which we generally hire
big boats that have the possibility of placing
the observers at least 5m above the deck so that
they can have a good view of the river and thus
count the animals."
Each time a scientist sees a
dolphin or a school of dolphins, their position
will be noted using GPS. Scientists will also
register if they are adults, young or new-born
mammals, as well as record information about their
habitat.
In addition to spotting the
pink river dolphin, scientists will also be on
the look out for the grey river dolphin (Sotalia
fluviatilis) — a dolphin species darker and smaller
than the boto, with a shorter snout and a distinctive
triangular dorsal fin.
END NOTES:
• The Omacha Foundation is a non-profit NGO working
to study, research and preserve flora and fauna
with an emphasis on freshwater ecosystems in Colombia.
The work is based on the mutual collaboration
between researchers and the community with the
aim of achieving plans for sustainable development
of the freshwater resources.
• The Participants: Fernando
Trujillo has more than 20 years of experience
in river dolphin and aquatic fauna research. From
2007, he will take up the position of president
of the Latin American Society of Aquatic Mammals
(Solamac). Catalina Gómez is a researcher
with the Omacha Foundation and has participated
in several dolphine counts in the Amazon. Marcela
Portocarrero is a researcher with the Omacha Foundation
and also has experience in the conservation of
fauna. Felix Daza is an investigator with the
Wildlife Conservation Society (WCS) in Venezuela
and is currently coordinating research in aquatic
ecosystems. Carlos Lasso is a specialist in the
ecology and taxonomy of fish in South America.
