OystersThere are many food items in the world that evoke the question: “How hungry did
the first person to eat that have to be?” But few such dishes can rival the raw
oyster for unpalatable appearance and general “ick” factor.
If undaunted
by the oyster’s rough, rock-hard, nearly-impossible-to-open shell, the
undoubtedly famished first taster would then have confronted the gray, slimy,
almost phlegmatic appearance of its plump body. Once beyond any primal gag
reflex though, this seminal slurper would have been surprisingly rewarded with
the oyster’s delicate, toothy texture, rich flavor, and salty liquor. Oysters
are also high in calcium, iron, and protein. Admittedly, they’re not for
everyone, but adventurous humans the world over have enjoyed oysters, raw and
cooked, for thousands of years.
Although it is possible for food oysters
to produce pearls, they should not be confused with actual pearl oysters, which
are from a different family of bivalves. True oysters, which belong to the
Ostreidae family, are found throughout the world’s oceans, usually in shallow
waters and in colonies called beds or reefs. Among the most popular and heavily
harvested species are the Eastern American oyster (Crassostrea virginica), found
in Atlantic waters from Canada to Argentina, and the Pacific oyster (Crassostrea
gigas), found from Japan to Washington state and as far south as
Australia.
Oyster shells are usually oval or pear-shaped, but will vary
widely in form depending on what they attach to. They are generally whitish-gray
in outer shell color, and their inside shell is usually a porcelain white. They
have extremely strong adductor muscles to close their shells when
threatened.
Oysters feed by extracting algae and other food particles
from the water they are almost constantly drawing over their gills. They
reproduce when the water warms by broadcast spawning, and will change gender
once or more during their lifetime.
Commercial harvesting of oysters is
regulated throughout most of their range, and they are not currently listed as
threatened or endangered. However, they are extremely sensitive to water quality
and susceptible to coastal pollution, and populations in many areas where they
were once abundant have dwindled or disappeared. They can also retain toxins in
their flesh, making them unhealthy for human consumption.