Dolphin Biology

Dolphin Life: What we’ve learned in 40 years

Dolphins, which breathe air, are warm-blooded and give birth to live young, get their name from the Ancient Greek delphis meaning “fish with a womb.” There are some 30-40 species of dolphins that vary in size from 4 feet and 80-100 pounds (such as the franciscana dolphin from coastal South America), to 31 feet and 10 tons (Orcas). Dolphins are found worldwide, from coastal waters to the deep, open ocean.

In Florida, male bottlenose dolphins (Tursiops truncatus) grow to about 9 feet long and can weigh some 600 pounds, while females reach 8 feet long and about 400 pounds. Elsewhere in the world, bottlenose dolphins can reach 12 feet long and more than 1,000 pounds. It isn’t unusual for them to eat more than 15 pounds of fish a day, and nursing females may eat more than 30 pounds each day. They are the most common and widespread type of dolphin in the coastal waters of Florida.

Long-term studies by the SDRP have included learning about dolphins’ basic biology, and especially how their biology changes over time and as they reach developmental milestones — growing from calf, to juvenile, to adult, for instance.

Measuring Dolphin Hearing

Researchers test dolphins' hearing using using auditory evoked potentials, or AEPs. During testing, sensors are placed on an animal’s head to measure brain activity in response to a sound. This is the same way