How much do dolphins weigh?
The weight of a dolphin will depend on many different factors. The species plays an important part in setting the parameters, but the exact weight of the dolphin could vary depending on their age, sex and geographical location.
The Maui’s dolphin is the world’s smallest dolphin and a fully grown adult weighs only 90 lb. The killer whale is the largest dolphin in the world and adult males can weigh up to 10 tonnes. There are 38 different species of dolphin in between those sizes which can weigh anything from 100 lb to a few tonnes. Killer whales are considerably bigger than the second-largest dolphin species but Maui’s dolphins are closely followed by several other species.
Baby dolphins are much smaller and lighter than the adults and some species can take up to 7 years to grow to their full size. Younger dolphins, therefore, will always weigh considerably less than those which are fully grown. For most species of dolphin, the adult males weigh considerably more than the adult females. In these instances, a female will never grow to be as big as a male regardless of how old she is or where she lives. There are, of course, exceptions to this rule. With most species of river dolphin the female actually grows to be bigger and heavier than the male.
For some species of dolphin there are variations depending on the geographical location where the dolphin spends the most time. For example, common bottlenose dolphin populations which live offshore tend to be larger and heavier than those which live in coastal waters, despite having exactly the same genetic information. River dolphins are smaller and lighter than a lot of marine species of dolphin. Their habitat means that they cannot afford to grow too big, otherwise they would be unable to swim down narrow tributaries and around obstacles such as fallen trees.
Dolphins are limited in the size that they will reach and will not keep putting on weight as they eat more food. They can consume a huge number of calories per day but they need a vast amount of energy to fuel them whilst they are constantly on the move.
Dolphins exert a tremendous amount of energy as they ride bow waves, leap, flip and jump as they breach the water and cover a huge distance every day. It is very difficult for a dolphin to consume excess calories and therefore will not put on weight in the same way that other mammals may do.Dolphin Facts | Dolphin Information | Dolphin Species | Dolphins FAQ