Shark Advice I: John Marrack
was swimming off Oahu with a pod
of spinner dolphins in June when
they "took off like rockets."
Moments later, a shark grabbed his
foot. He was rescued by a passing
boater, but his foot was broken and
the skin shredded. The moral: "If
the dolphins change their behavior
or disappear, get out of the water,"
says shark researcher Gerald Carr,
of the Waikiki Aquarium. Carr said
he has had shark encounters while
swimming at Midway Island. When
dolphins became agitated or left
the area, a Galapagos shark or
other shark species was almost surely
in the vicinity. His orders to fellow
swimmers were to get out of
the water: "The landlord is here."
(The Honolulu Advertiser)
Shark Advice II: If you are
snorkeling or diving where a great
white shark is looking for food,
well, you're shark bait. On August
19, a woman in a full wet suit,
mask and fins was snorkeling with sea lions off California's central
coast, when a great white attacked
and killed her. John McCosker,
senior scientist with the California
Academy of Sciences in San
Francisco, says "If you are wearing
a wetsuit and fins and you are
swimming with sea lions, you are
doing a clumsy job of imitating
shark food." McCosker has done
shark research inside an underwater
cage among sea lions. "All
of a sudden all the sea lions disappear
-- and then you see the white
shark." It arrives so fast that there
is little a person can do to swim
way. McCosker and his coresearchers
have interviewed every
single living shark attack victim on
the West Coast (there have been
108 attacks since 1952, ten fatal).
"None of the living victims ever saw
the shark in advance," he said. "It
all happens too fast." (San
Francisco Chronicle).
Give Us All the Poop:
Subscriber Patricia Harmon took us to task for our comments in
August about the Ft. Lauderdale
live-aboard Easy Goin'. "While we
spent a long weekend on Easy
Goin' and had a nice time and
agree with the review, there is no
mention of the bathroom facilities.
With seven passengers and three
crew, there is only one bathroom.
For emergencies when that bathroom
is occupied, there is a chemical
toilet. Additionally, the toilet in
the bathroom is such that toilet
paper may not be placed in it, so
soiled toilet paper must be put in a
plastic bag and one must be sure
to spray the deodorizer after each
use. A suggestion for Undercurrent:
Accept no live-aboard reviews
unless there is a description of the
bathroom facilities." Thanks, a
point well made.
Antimosquito Coils Release
Toxic Fumes: In your room in the
tropics, you have no doubt burned
those green, insecticide-treated spiral
strips, letting them smolder
through the night to keep
mosquitoes at bay. Scientists have
found, however, that they can cause asthma and wheezing in children.
Furthermore, the smoke carries
pollutants such as formaldehyde. A
single burning coil can release as
much of the carcinogen as 51
cigarettes. The airborne particulates in
the smoke are equivalent to those
released by 137 cigarettes. Particles
that small can carry toxic compounds
deep into the lungs. (Science News, July
12, 2003).
Seeing Without a Mask: Diving
without masks, members of the
Moken tribe (who live on islands in
Thailand's Adaman Sea) can spot
Shells that most people would be
unable to distinguish from surrounding
rocks. Anna Gislen, a Swedish scientist,
found that Moken children and
European children have the same visual
acuity on land, but the Moken have
better than twice the underwater
resolving power, a level previously
thought to be impossible. They do so
by shanking the size of their pupils to
a diameter 22 percent smaller than
the minimum seen in Europeans,
whose pupils enlarge slightly underwater,
in response to the lower light. This
reaction -- which is routine in Moken
children -- is absent in European children.
But Islen found that Swedish
children can be trained to constrict
their pupils when diving and enhance their underwater visual acuity. That
suggests the Moken learn the skill and
do not inherit it. (Washington Post)
Remember Crocodile Dundee:
Cozumel has a "transvestite problem,"
says an article from El Semanario. To
eradicate it, being dressed as a woman
in a cantina gets a penalty and repeated
offenses could lead to the closing
of the bar, which happened to Rex's
Cavern. The city treasurer says that
"We hope is that the tranvestites won't
mix with other people, because that is
when prostitution can arise."
New Dive Destination: Australian
scientists have stumbled on an
uncharted coral reef. At 120 sq. km, it
covers a larger area than all the reefs
of Barbados put together. "We were
stunned when we lowered a video
camera down there and saw living
hard corals," said Peter Harris, who
led the Geoscience Australia expedition.
The reef has probably escaped
notice until now because most of it is
more than 20 m below the surface
and because of its remoteness. The
nearest big settlement is the town of
Karumba, 250 km to the southeast.
They have always thought that the gulf
was too clogged with sediment for
reefs to grow, so it might not be a
diver's dream.