in the western
North Atlantic, reaching a maximum length of only about 5.6 feet (1.7
m).

Their body shape is very similar to that of the Atlantic bottlenosed
dolphin, though the beak is less clearly demarcated from the forehead.

The rather prominent dorsal fin is nearly triangular, curving only
slightly backwards near the tip.

Guiana dolphins are steel blue to dark brown on the back and white on
the belly. There is sometimes a brownish band extending from the dark
color of the back in front of the dorsal fin back towards but not
reaching the anus.

Natural History Notes

Guiana dolphins are usually found in groups of fewer than 10
individuals.

May Be Confused With

Because of their limited range and specialized habitats, Guiana dolphins
are unlikely to be confused with any other cetacean species except
perhaps Atlantic bottlenosed dolphins (p. 128). These two species can be
distinguished by the following characteristics:

GUIANA DOLPHINS ATLANTIC BOTTLENOSED
DOLPHINS

SIZE

To only 5.6 feet (1.7 m). 8 to as much as 12 feet
(2.4 to 3.7 m).

DORSAL FIN

More nearly triangular; curved Broad-based, tall, and
only slightly backwards falcate.
near tip.

DISTRIBUTION

Found in rivers and estuaries, Sometimes found nearshore
extend into only very and in bays, river mouths,
shallow nearshore waters on and estuaries, but extend
limited area of South American farther offshore.
coast.

Distribution

Guiana dolphins are found in Lake Maracaibo, in the rivers of Guyana,
and in the nearshore coastal waters of the northeastern portion of the
Guianas.

Stranded Specimens

In their very limited range, stranded Guiana dolphins can be readily
identified by their extremely small size (to 5.6 feet [1.7 m]) and
nearly triangular dorsal fin. Furthermore, in addition to the
characteristics listed above distinguishing living Guiana dolphins from
Atlantic bottlenosed dolphins, the species can be distinguished by
differences in the numbers of teeth:

ATLANTIC BOTTLENOSED GUIANA DOLPHINS
DOLPHINS

TEETH

20-26 in each upper jaw; 26-35 in each jaw; often
18-26 in each l