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Dolphins
& Porpoises
Sharks
Mola mola or Ocean sunfish
Dolphins
& Porpoises
Dolphins are marine
mammals of the suborder Odontoceti (the toothed whales)
from the family Delphinidae. Their close "cousins" porpoises,
are in the family Phoconenidae. There is not much difference
between these (porpoises have shorter snouts) and it is more sensible
to describe dolphins and porpoises as "small cetaceans with a dorsal
fin" the way a standard guide by Leatherwood et all does. Cetaceans
were flourishing in the oceans in much the same form some 9 million
years before humans ever arose on the planet.
Dolphins. Photo: Clay
Wiseman
Of the twenty or so
species found in the central and northern Pacific, nine are most
likely to be seen in Monterey Bay: killer whales, false killer whale,
Risso's dolphin, Pacific white-sided dolphin, northern right whale
dolphin, Dall's Porpoise, harbor porpoise, bottlenose dolphin, and
common dolphin.
Humans have historically
"bonded to" or "loved" dolphins. And it has not been a one-sided
affair. Many species of these small cetaceans -- "dolphin/porpoise"
-- approach humans and love to ride the wakes of boats, though not
all are so folksy. Common dolphins are less likely to jog along
with boats than Dall's porpoise. Risso's dolphins are exceptionally
wary of approaching craft and will bunch together in defense. Among
the most curious and friendliest seem to be bottlenoses.
Locally, a pod of about
40 bottlenose dolphins are frequently seen ranging through the area.
Many early morning beach-strollers have described groups of them
tagging along as the people strolled, just beyond the surf, as if
the dolphins were "human watching".
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Sharks
Sharks are referred
to as Elasmobranchs, or "strap gills", in science, a reference
to their gill slits, which are different in kind from the gill structures
of the teleosts, or bony fishes -- the critters we commonly
think of as "fish".
World -- or ocean --
wide, there occur over 250 species of sharks comprised several families,
like Squalidae, Alopiidae, Lamnidae, and Carcharhinidae.
Sharks have a low reproduction rate, are long lived fish, and many
populations and species are in danger from overfishing.
Shark. Photo courtesy
Monterey Bay Aquarium.
In our region of Monterey
Bay, one can expect to find blue sharks, thresher sharks, smoothound
(grey and brown) sharks, spiny dogfish, leopard sharks, basking
sharks, sand sharks, great whites, mako (or bonito) sharks, and
a rare salmon shark or so. A respectable shark ranges from 4-feet
in length up to 30 feet for basking sharks.
There are many fascinating
things about elasmobranchs, such as the fact that not a single bone
is to be found in a shark's body. All their skeletal structures
are cartilage. or gristle. Their skin is made of the same stuff
and design as their teeth; placoid scales covered with dentine.
Their teeth are always being replaced in rows.
In sharks, the olfactory
lobes of their brains are dominant, not the optic ones. Their habits
are informed by what they smell more than what they see. A shark
is able to detect a trace of blood in several thousand parts of
water. Their sense of hearing is also pronounced; able, it appears,
to hear low frequency noises of thrashing wounded fish from long
distances. Sharks also have lampulae lorenzini sensory
structures in their noses that allow them to detect electrical fields
around bodies.
Everybody likes to marvel
about great whites, the biggest baddest beast in the ocean. And
there are a number of them in our central California coastal area;
quite possibly more than ever before. The great whites, it is said,
are attracted by the increasing populations of elephant seals and
sea lions especially in the Ano Nuevo area midway between Santa
Cruz and Half Moon Bay.
For all the talk one
hears about sharks from visitors to the Wharf, there has never been
a shark attack here. If you would like to learn more about elasmobranchs,
don't miss the Wharf Shark Festival this summer!
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Mola
mola or Ocean sunfish
A strange thing about
the Mola mola is they are commonly called by their Latin scientific
name, which must rank among the rarest of events in the animal kingdom.
The Mola mola,
or ocean sunfish as it is also called, looks like it started out
to be a spaceship, thought better of it, and became a fish. They
can get enormous; up 13-feet long (a picture of one hangs in Gilda's
Restaurant), but are more commonly seen at about 5-feet long. Somedays
there are a lot of them lounging at the surface on their sides,
as if they have just put on the oil and are soaking up the rays.
Mola mola or Ocean
sunfish
They can be found basking
at the sea surface on calm days from British Columbia to South America.
They are a flat fish, eyes on both sides (unlike halibut), with
a long dorsal and anal fin positioned at the rear of their round
bodies looking more like fins on a Cadillac, or a spaceship, than
anything a fish could use. Their small mouths seem formed in a perpetual
pucker. With it, they eat only jellyfish.
Because Mola molas are
not very tasty, they are generally left alone by fishers. Actually,
there is a section of them deep within them that has a strange jelly-like
consistency, which when fried up, changes into a meatier form, and
ends up tasting much like abalone.
They are
very curious animals and will often come up to a small boat for
a while to watch or let a small boat approach very close without
getting startled. One local fisherman even thinks it's bad luck
to catch them. "They're peaceful, man. It's bad karma to catch Mola
molas. They only eat jellyfish -- they're peaceful, man."
Under
the Wharf Magazine & Photography, 831-469-0443
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