Dolphin Tales: What do dolphins and bats have in common?
The nooks and crannies underneath the Matlacha Bridge are home to approximately 2,000 Brazilian free-tailed bats. Just one bat can consume up to 3,000 insects in a single night. They provide a very effective form of natural insect control.
Dolphins and bats use echolocation to locate objects and prey through sound waves. The waves contain information about the size, speed, distance and direction of an object. Both species emit high pitched sounds and listen for echos. This allows dolphins to see in muddy waters or dark ocean depths. It allows bats to fly at night as well as in dark caves to locate night flying insects.
Dolphins make echolocating sounds by squeezing air through nasal passages near the blowhole. These sound waves then pass into the forehead, where a big blob of fat called the melon focuses them into a beam. By moving its head to aim the sound beam at different parts of a fish, a dolphin can also differentiate between species.
Bats make echolocating sounds in their larynxes and emit them through their mouths. Bats can detect an insect up to 16 feet away, work out its size and hardness, and can also avoid wires as fine as human hairs. As a bat closes in for the kill, it cranks up its calls to pinpoint the prey.
Echolocating sounds are so loud that the ears of dolphins are shielded to protect them. The bat turns off its middle ear just before calling, restoring its hearing a split second later to listen for echoes. A bat can scream up to 140 decibels, as loud as a jet engine 100 feet away. Fortunately for humans, we cannot hear these high pitched frequencies.
Capt. Cathy Eagle has spent over 40 years boating in our local waters. As a professional charter captain, she specializes in dolphin and nature tours. Visit CaptainCathy.com or call 239 994-2572.