They are not only pink…
The Bolivian river dolphin, locally also known as “Bufeo”, is the only cetacean (whale, dolphin, and porpoise) present in Bolivia. They are found in rivers and lakes where they are most often seen alone or in pairs, but groups of more than ten individuals have been observed as well.
River dolphins have several characteristics that set them apart from dolphins living in the sea. Although the body is solidly built, river dolphins have a flexible neck which they can move from side to side. Also, their very agile pectoral fins and short dorsal fins allow them to manoeuvre in shallow waters and through submerged vegetation. With their long beaks, river dolphins can extract their prey from their hiding places.
The diet of the Bolivian river dolphin is hardly studied. But looking at its closest relative, the Amazon River dolphin, in Brazil, they may also feed on a large variety of fishes (more than 40 species).
WHY ARE THEY IMPORTANT?
Indicators of the health of rivers and lakes
River dolphins rely on rivers and floodplains to sustain their diet of fish and so play an important role in keeping the health and stability of these environments. Main rivers are also used by dolphins as a corridor to move to different areas for food and refugia. Being top-predators which are sensitive to environmental changes, river dolphins are seen as ideal indicators of the condition of their natural environment. Knowing and protecting the health of their natural environment is also of benefit for other animals and people leaving near and being dependent on the river.
CURRENT SITUATION AND THREATS
Various human-related impacts threaten river dolphins
Currently, the Amazon River dolphin is categorized as ‘Endangered by’ the International Union for Conservation of Nature (IUCN). This has increased the urgency to carry out actions for the conservation of river dolphins.
Various human-related impacts threaten river dolphins such as water pollution, fishery-related impacts and habitat loss.
Water pollution – contaminants from agriculture such as pesticides and wastes from industries such as mining enters rivers and reduce the water quality, causing less suitable habitats to live in for dolphins.
Fishing-related – fishing-related threats to dolphins are the unintentional entanglement in fishing nets but also the intentional use of river dolphins as fishing bait.
Habitat loss – habitat loss is also a major threat to the future survival of river dolphins. The construction of dams can lead to less available habitats and food supply for dolphins, and dolphin populations can become fragmented and isolated. Also, climate change is seen as a possible cause of loss of available habitat for dolphins. Effects are changes in the ecology of the river due to reduced water levels and currents, but also a decrease in the food supply for dolphins.
WHERE YOU CAN FIND RIVER DOLPHINS IN BOLIVIA
The Amazon in Bolivia
Bolivia is characterized by a great diversity of ecological zones ranging from snowy mountains up to 6.500 meters above sea level, highlands, valleys, tropical forest, savannas, to deserts.
Most of the distribution range of the Bolivian river dolphin overlaps with the north and northeast of the Bolivian Amazon which covers approximately 45% of Bolivia. This area is characterized by a very dynamic nature and has a wide variety of flora and fauna, which are partly preserved in several protected areas. The most important ones are the Madidi National Park and the Noel Kempff Mercado National Park.
Major rivers in Bolivian inhabiting river dolphins are the Madeira, Mamoré and the Iténez River, which are tributaries of the Amazon River, the most magnificent river of South America. River dolphins don’t seem to have a preference for a specific water type (like clear, white or black), but it appears that they favour areas such as confluences, sharp bends, and sandbars for their higher fish prey abundance.
The region inhabited by river dolphins is also home to ancient indigenous people as Moxeños – Trinitarians, Yuracarés, Yuquis, Pacahuaras, Chimanes, Lecos, Tacana, all with their own unique culture and heritage.
For tourists, the Bolivian Amazon offers beautiful landscapes with various travel services such as adventure tourism, wildlife watching, community tourism, cultural tourism.
Map of South-America showing the rivers inhabited by river dolphins of the genus Inia delineated in blue. Country border of Bolivia in green.
[IUCN (International Union for Conservation of Nature) 2011. Inia geoffrensis. The IUCN Red List of Threatened Species. Version 2019].
WHAT'S BEING DONE
TO PROTECT THEM
Research and outreach to protect the Bolivian river dolphin
Biologists are increasingly learning about the life of Bolivian river dolphins. However, there is still much to discover. Also, given the threats they face, there is a strong need to continue research and conservation activities. Continuous monitoring of the abundance, distribution and behaviour of river dolphins are essential to help indicate critical habitats for river dolphins and to identify changes in river dolphin populations. Besides collecting scientific data on river dolphins and their natural environment, biologists can use the gathered information to inform people on how to best use the resources present for their existence meanwhile helping to protect the river dolphins in Bolivia in the long-term.