10 Aug
2006 Napo River, Ecuador – Dozens of dolphins
have been sighted in the rivers of Ecuador as
part of a South American freshwater dolphin survey
in the Amazon.
The survey, led by Colombian
conservation NGO Fundación Omacha, with
support from WWF, the Wildlife Conservation Society,
Fundación La Salle and the Whale and Dolphin
Conservation Society, counted 33 pink river dolphins
and seven gray river dolphins during an expedition
through the Ecuadorian Amazon, along the Napo,
Lagarto Cocha, Cuyabeno and Yasuni Rivers.
“We are pleased that we have
sighted a good number of these vulnerable freshwater
species,” said Fundación Omacha Director
Fernando Trujillo, “but we are still very concerned
about threats that are affecting overall population
numbers.”
River pollution, deforestation,
indiscriminate capture and incidental fishing
are some of the factors affecting the South American
river dolphins. Oil exploration is also a factor.
“Aquatic ecosystems are particularly
vulnerable to direct and indirect impacts from
this activity, mostly because it pollutes the
rivers and increases the number of motor-driven
vessels,” said Victor Utreras of the Wildlife
Conservation Society.
“Dolphins are very sensitive
to acoustic pollution and threatened by collisions
with fast moving vessels.”
The South American river dolphin
survey expedition, which consists of scientists
from Colombia, Peru, Ecuador, Bolivia and Venezuela,
started in May in the Venezuelan city of Ciudad
Bolivar. Following the recent freshwater dolphin
survey in Ecuador, another expedition will take
place in the Meta River in Colombia in August,
followed by two more in Peru and Bolivia in September.
The overall aim of the survey
is to establish how many river dolphins there
are in the Amazon and Orinoco Rivers and their
tributaries.
“Along with estimates of river
dolphin populations, we are also gathering as
much information on potential threats and conservation
status on the species in the areas we visit,”
said Saulo Usma, WWF Colombia’s Freshwater Coordinator.
“This information will contribute
to the design of management plans and specific
conservation actions in the headwaters of the
Amazon.”
• The pink river dolphin (Inia
geoffrensis), also known as the boto, is found
in lowland fast flowing, white-water 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
get tangled up in fishing nets, or suffer wounds
by colliding with boats. In addition to spotting
the pink river dolphin, scientists are also on
the look out for the gray river dolphin (Sotalia
fluviatilis) — a dolphin species darker and smaller
than the boto, with a shorter snout and a distinctive
triangular dorsal fin.
Maria Ximena Galeano
