Biology of River Dolphins

Biology of River Dolphins
About Pink dolphins
Social Habits

Ecological factors strongly influence social behavior. Because Amazon River dolphins do not have any known natural predators -- other than humans -- they do not need to live in large groups, or "pods," protection as many dolphin species.

Inia geoffrensis (pink dolphins) engage in solitary hunting/feeding strategies during the high water season when their prey fishes disperse into the floodplains. At other times, they are found in small "family" groups of 5-8 animals which seem to be led by a dominant adult male. At river confluences, we have seen as many as 35 pink dolphins cooperatively herding and banking fish, often in association with the gray dolphins.

Sotalia fluviatlis (gray dolphins) are strongly gregarious animals and manifest strong social ties with their own kind. Given that they seem to practice a polyandrous breeding system and females tend to be a bit larger than males, they may have a matriarchal social order.
About Pink dolphins
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