Interesting articles…..
Sharks
leave deep waters, migrate inshore
John Yeld
September 28 2006 at
03:26PM
Great
white sharks appear to be following their expected spring season migration into
the inshore areas of
The
sharks' general movement away from
Shark
spotters have started reporting regular sightings this past week:
There
were white sharks off Muizenberg, St James and Fish Hoek last Friday, on Sunday and again on Tuesday.
There
was a sighting at Fish Hoek; and another shark was
seen at St James on Wednesday.
On
Saturday, five of the 35 acoustic receivers that monitor great white shark
movements in
Experienced
divers recovered four monitors at Muizenberg and one
at Partridge Point, near Simon's Town.
These
receivers detect the presence of a great white shark tagged with an acoustic
transmitter and store information, such as which individual sharks were in the
area, when they arrived and departed, and how long they stayed for.
Sixty-four
great whites have been tagged with the transmitters so far, including 18 tagged
earlier this year.
Most
of these sharks were tagged during the winter months off
Shark
Working Group spokesperson Gregg Oelofse said the
information retrieved from the receivers recovered on Saturday confirmed the
results from last year's research and provided valuable information of great
white shark behaviour in
"Throughout
the winter period, great whites were occasionally recorded on the Muizenberg receivers, but because of the low number of
detections recorded, it appears as if most of the records were from sharks swimming
more than a kilometre offshore," said Oelofse.
"However,
since the end of August and early September, not only have more tagged sharks -
six so far - been recorded in the area, but they are also starting to spend
longer periods of time here, closer to shore, ultimately leaving Seal Island
completely for the summer period.
"This
corresponds to a decrease in observations and records from the
Based
on last year's information and the data retrieved on Saturday, it was expected
that white shark inshore activity would increase in the coming weeks, said Oelofse.
"What
is clear is that this seasonal change is not unique to
"Similar
behaviour is recorded in Gansbaai,
"And
anecdotal evidence from fisherman and military exercises suggests it has been
occurring in
The
information collected by the shark spotters is being correlated to the records
from the acoustic receivers.
The
shark spotted at Baileys Cottage on Friday was most likely a 3,5m female great
white tagged at
"The
time that the shark was sighted by the spotters - at 2pm - correlates exactly
with a record recorded by the acoustic receiver," said Oelofse.
More
sea floor acoustic receivers will be retrieved at
Next
month, a large-scale inshore tagging operation is planned when researchers will
attempt to place transmitters on about 10 great whites that are already
swimming near inshore areas like Muizenberg and Fish Hoek.
"Based
on last year's data as well as this year's most recent data, the Shark Working
Group would like to ask people using the coast for recreation to be
extra-vigilant, particularly over the next few months when the highest
occurrence of inshore white shark activity is expected," said Oelofse.
"People
are encouraged to use areas where shark spotters are on duty and to take the
time to speak to them on the day they visit the beach to find out about recent
sightings and activity as well as the current conditions which determine the
effectiveness for shark-spotting.
"People
are also requested to please take the time to read the shark-spotting signs to
inform themselves of the four-flag warning system
used, as well as be aware of the use of a siren to close the beach".
Beware
during summer when sharks are closer
Staff Writer
September 29 2006 at
04:33AM
The
shark working group has issued a warning of a probable increase in in-shore
shark activity along the
The
group warned the public to be "extra vigilant" during this time and
to use areas where shark spotters were on duty. "Take the time to speak to
them to find out about recent sightings and activity, as well as current
conditions which determine the effectiveness for shark spotting."
The
group has also asked the public to read the shark spotting signs so that they
know about the four-flag warning system, and to be aware of the use of a siren
to close the beach.
During
the past week, there have been regular sightings of Great Whites by shark
spotters, the group said in a statement released on Thursday.
Last
Friday, Great Whites were seen at Muizenberg, Fish Hoek and St James. On Sunday, one was seen at Fish Hoek and another there on Tuesday. One shark was spotted at
St James on Wednesday.
The
group said that last Saturday, five of the 35 sea floor acoustic receivers that
monitored the presence of Great White sharks in
"It
is expected, based on last year's information and on the data retrieved on Saturday, that white shark inshore activity will increase in the
coming weeks," the statement said.
They
said that throughout winter, Great Whites were occasionally recorded on the Muizenberg receivers, but it appeared as if most of the
records were from sharks swimming more than a kilometre
offshore, mostly at
"However,
since the end of August and early this month, not only have more tagged sharks
- six so far - been recorded in the area, but they are also spend longer
periods closer to shore."
The
sharks would eventually leave
Data
was being collected on environmental conditions and on the availability of prey
to determine the reasons for sharks moving from the seal colony in winter to
the inshore areas in summer.
The
group said this seasonal activity was not unique to
Great
white eludes False Bay tag team
September 29 2006 at
02:08PM
By Natasha Prince
It
was another dramatic day for beach-goers at Fish Hoek,
After
being forced to leave the water at about 8:30am, bathers were eventually
allowed back in at around 3pm, said Yvonne Kamp, co-ordinator of the shark spotters who look for sharks from
vantage points at designated beaches.
"When
the siren sounded people quickly left the water. Everyone seems to be used to
the drill by now," said Kamp.
'We
are asking that people be more alert'
The
great white shark spring migration has begun, say the experts who have warned
bathers to be more cautious.
Researchers
rushed to try to tag the shark in Fish Hoek bay
Thursday but were unsuccessful.
Law
enforcement officials controlled watching crowds and made sure nobody entered
the water.
Shark
spotters have been kept on their toes for the past few days in anticipation of
the shark migration to the inshore parts of
The
sharks are moving away from
Sharks
have been sighted just off the coast at Muizenberg,
St James and Fish Hoek since last Friday.
There
was a sighting on Wednesday at Fish Hoek and another
at St James.
The
sharks' inshore activity is expected to increase in the coming weeks.
Gregg
Oelofse, environmental officer of the Cape Town City
Council and member of the Shark Working Group, said that fortunately visibility
had been good on Thursday.
"We
are asking that people be more alert and take notice of the flags," said Oelofse.
A
green flag means the beach is open and swimmers can have a dip and a black flag
indicates poor visibility for spotters. A red flag indicates that bathers
should be cautious because a shark has been spotted nearby. A white flag with a
black shark indicates a danger zone and bathers should leave the water
immediately.