Boto
Inia geoffrensis

Other Names: Amazon River Dolphin, Pink Porpoise, Pink Dolphin

Habitat: Riverine

Status: Locally common

Population: Unknown

Threats: Entanglement in fishing nets, hunting/whaling, pollution, habitat destruction, human disturbance

Group Size: 1-2, up to 15 in dry season or at good feeding grounds

Fin Position: Slightly behind center

Newborns: 30-32 in (75-80 cm), c.15 lbs. (7 kg)

Adults: 6-8 ¼ ft (1.8-2.5 m), 185-355 lbs. (85-160 kg)

Diet: Fish and occasionally krill or other crustaceans

Teeth: 46-70 on both top and bottom rows

Description

Dorsal fin:

- dorsal ridge extends forward and backward from hump
- hump instead of dorsal fin

Flukes:

- broad flukes
- ragged trailing edges
- distinct notch in middle
- pointed tips
- flukes seldom show above surface

Flippers:

- flippers curve to a point
- ragged trailing edges

Head:

- crescent-shaped blowhole placed left of center
- shape of melon cab be changed at will
- abrupt forehead
- neck creases may be extensive
- flexible neck
- mouth line turned up at corners
- short bristles on upper and lower jaws
- slender, slightly down-curved beak

Head-on View:

- large, bulging cheeks may hamper downward vision, so often swims upside down

Other characteristics:

- plump body tapers to tail
- bluish gray, vivid pink, or off-white body color

Behavior

- blow can be loud and tall, sometimes reaching 6 ½ ft (2 m), but is normally slow and deliberate, sounding like a sigh
- approachability varies from area to area
- most active in early morning and late afternoon
- chasing, nipping, and flipper-waving may be observed
- known to bow-ride and wake-ride
- occasionally breaches - often over 39 in (1 m) in the air - and may lift head above the surface, through usually only melon and blowhole appear above the surface, followed by part of dorsal ridge; body bends higher in the air when animal is more active
- most dives last 30 to 40 seconds

Distribution

- all main rivers of the Orinoco and Amazon Basins, South America
- Occurs in Venezuela, Columbia, Ecuador, Bolivia, Peru, Guyana, and Brazil
- found more than 1,865 miles (3,000 km) inland in some areas
- most common at turbulent junctions of rivers and tributaries, just below rapids and close to shore
- in dry season (August to November), confined to main rivers and tributaries
- in flood season (December to June), frequently enters flooded jungles and grasslands, swimming between trees
- when water recedes (from July onward), levels can drop by as much as 35 ft (10 m), and dolphins are sometimes stranded in ponds
- look for flocks of terns, which are often associated with feeding bouts


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This page was created by:Candice Orca Mottet