Endangered
Amazon river dolphin
Inia geoffrensis
The Amazon river dolphin, also known as the boto, bufeo or pink river dolphin, is a toothed whale endemic to South America and is classified in the family Iniidae.
Appearance
The flukes are broad and triangular, and the dorsal fin, that is keel-shaped, is short in height but very long, extending from the middle of the body to the caudal region. The body color varies with age. Newborns and the young have a dark grey tint, that in adolescence transforms into light grey, and in adults turns pink as a result of repeated abrasion of the skin surface.
Adult males reach a maximum length and weight of 2.55 metres (8.4 ft) (average 2.32 metres (7.6 ft)) and 185 kilograms (408 lb) (average 154 kilograms (340 lb)), while females reach a length and weight of 2.15 metres (7.1 ft) (mean 2 metres (6.6 ft)) and 150 kilograms (330 lb) (average 100 kilograms (220 lb)).
Range and habitat
The Amazon river dolphin is located in most of the area's aquatic habitats, among them. River basins, major courses of rivers, canals, river tributaries, lakes, and at the ends of rapids and waterfalls. Cyclical changes in the water levels of rivers take place throughout the year. During the dry season, dolphins occupy the main river channels, and during the rainy season, they can move easily to smaller tributaries, to the forest, and to floodplains.
In another study, on a stretch of 120 kilometres (75 mi) at the confluence of Colombia, Brazil and Peru, 345 individuals with a density of 4.8 per square km in the tributaries around the islands. 2.7 and 2.0 were observed along the banks.
Habitat labels include fresh water.
Pins are Wikidata “endemic to” fields. Orange dots, when present, are GBIF occurrence tiles — survey bias included.
Diet and breeding
During prey time, as many as 35 pink dolphins work together to obtain their prey. Due to the high level of prey fish, larger group-sizes are seen in large sections that are directly influenced by whitewater (such as main rivers and lakes, especially during low water season) than in smaller sections influenced by blackwater (such as channels and smaller tributaries).
Breeding is seasonal, and births occur between May and June. The fin size, unfused vertebrae, and its relative size allow for improved maneuverability when navigating flooded forests and capturing prey.
In crisis
In 2018, this species was ranked by the International Union for Conservation of Nature (IUCN) as endangered, with a declining population. It was said to be difficult to train, and had a high mortality rate among captive individuals. A series of rapids and waterfalls in the Madeira River have isolated one population, recognized as the subspecies I. G. Boliviensis, in the southern part of the Amazon basin in Bolivia.
Studies to estimate the population are difficult to analyze due to the difference in the methodology used. In a study conducted in the stretch of the Amazon called Solimões River, with a length of 1,200 kilometres (750 mi) between the cities of Manaus and Tabatinga, a total of 332 individuals was sighted ± 55 per inspection.
CITES lists this taxon on Appendix II. Confirm the current appendix on the CITES checklist.
Amazon river dolphin is Endangered on this catalog because that is the IUCN category stored on Wikidata. Confirm the official criteria and any later count on iucnredlist.org.
Sources
Written for this catalog from the English Wikipedia article on Amazon river dolphin, Wikidata item Q205329. Family and order context is original field-guide writing about the group, not a copied assessment of this one species. Wikipedia text is CC BY-SA. Not an IUCN assessment. Counts, when quoted, can change — confirm them on the recovery programme and on iucnredlist.org.
