NEPTUNE 911 For Kids: Common Dolphin Herds Show Off

Common dolphins. C. Coimbra Photo

A herd of common dolphins, at least 500 in the herd, joined in our search for the blue whale off the shores of San Diego, CA this summer. Hundreds and hundreds rode alongside our boat. They are beautiful, playful, and noisy cetaceans.

They swim fast. And they can fly out of the water, spin, and make a perfect 10-point landing back into the ocean.

These common dolphins seem to like riding the waves that a boat makes. They also follow the front (bow) of a boat.

Common dolphins are colorful too. With all of their special markings that run from gray, to black, to yellow, to white, it looks like a fancy paint job.

Testing the Waters

The northern elephant seals pups born during the winter are now called "weaners." Thousands of these 300-pound weaners test the waters. In other words,they are teaching themselves how to swim.

You read that right. Northern elephant seal pups and weaners do not know how to swim. Their mothers left them behind just 4-weeks after they were born. So, now they are on their own, grouped together in "weaner pods" and the beach and nearby tidepools are their classroom.

By April most of these fat weaners will have developed muscle from playing in the water. They will swim like athletes, and dive like Olympic stars. That means it is time for them to leave the safety of their birthplace and begin a 6-month adventure in the Pacific Ocean.

The next time you and I can see them is when they return to their beach sometime around September.

About Humpback Whales

From NOAA

How did the humpback whale get its name?

The humpback whale gets its name from fact
that the dorsal fin sits on a large “hump” on
the back, which is noticeable when the whale
arches its back and dives. The scientific
name, Megaptera novaeangliae, means “big
wing of New England.” The “big wing” refers
to the humpback’s very long flippers, which
can be one-third of its body length.

What do they look like?

Humpback whales can be easily identified by
their markings. They are rorqual whales - a
set of whales that are all in the family
Balaenopteridae, have ventral (head to tail)
grooves on the throat, and a small, pointed
dorsal fin. The grooves allow the throat to
expand so they can take in huge amounts of
water when they feed. The grooves contract
and push out the water, which is filtered
through baleen.

This is an adaptation that developed to help it
efficiently eat the tons of food needed for its
survival. Baleen, made of fingernail-like material
called keratin, hangs down in a humpback’s
mouth and catches the food. Humpback whales
have between 270 and 400 pairs of baleen and
each is approximately 30 inches long. The
plates are rough enough to filter prey such as
krill.

Humpbacks have an irregularly shaped dorsal
fin located two-thirds of the way back of the
body and very long flippers.

Humpbacks have large bumps on the leading
edge (front) of the flippers as well as bump-like
knobs on the head and lower jaw. Each of the
bumps on the head and lower jaw are a called
“tubercle.” They contain stiff hairs, like a cat’s
whiskers, that may help humpbacks regulate
temperature or sense things in the water.

Many humpback whales are also home to
barnacles that stick to their skin.

Humpback whales usually dive underwater for 3-5 minutes.

NEPTUNE 911 For Kids

Common Dolphin Herds Show Off

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