Sunday, June 29, 2014

Far from mindless.........

"This new technology is shedding all kinds of light on their behavior that's been going on for millions of years." stated Toby Daly-Engel, a University of West Florida shark biology and genetics researcher.

The private research group Ocearch has been capturing and tagging Great White Sharks in the waters off Cape Cod MA for the past few years so that scientists can have a better idea of their actual movements.  the Great White is not an endangered species yet but it is considered to be a protected one.  Oceanrch tagged four Great Whites during 2012 and 2013 with a satellite pop-up tag that will record the depth of water the shark is in, water temperatures and location it is in.  That tag is combined with an acoustic tag that will be tracked by receivers along the east coast.

Three of the Great Whites have added huge amounts of information for scientists to analyze in the past year.  Katharine and Betsy have been moving down the east coast of the US.  Katharine, a 14 foot long, 2,300 pound shark has been leading the way down the coast.  She is named by Cat products fans after Katharine Lee Bates, who is a native of Massachusetts and writer of the song "America the Beautiful."  Betsy is smaller of the two at 12 1/2 feet long, weighing in at 1,400 pounds and seems to be following Katharine down the coast at a slower rate.  Scientists know where both sharks are because when they surface from the depths, the tags they carry will automatically download the information they have.

They were both tagged in August of 2013 and have since traveled about 5,000 miles around the tip of Florida.  The guess is that they will both be near Texas in the next month.  Katharine seems to surface more often and the public can track where she is through the Ocearch website.  Betsy on the other hand disappeared from tracking for quite a time earlier this year but she has again been tracked through her tags.  Both of these sharks are following fish along the coast, much like Genie and Mary Lee, also caught in the waters off Cape Cod.

A study released in 2011 had reported that there were only 219 Great Whites left in two Eastern North Pacific locations but a new study released in 2014 now puts there numbers at around 2,000 in these locations.Very little is actually known about Great Whites in the Atlantic and scientists are eager to discover more about where they mate, give birth and travel to feeding.  The newly tagged sharks are going to give them plenty of data for analysis.

The program also managed to catch and tag Lydia near the Mayport Poles surfing area in Jacksonville FL who turned out to be a 14 1/2 long, 2,000 pound female Great White.  She has become the first to be captured and tagged off the southeastern US coast.  She has also spun the heads of scientists with her path of travel.  She has become the first Great White to cross the Mid-Atlantic Ridge to England.  She has traveled 19,400 miles in the past year after being tagged and surprised scientists by traveling 313 miles in one 72 hour stretch.  Recent data has shown that Lydia seems to be turning away from England now and scientists speculate as to whether she is headed for the Mediterranean Sea to give birth.

When she had been caught and tagged, scientists believed that she was not pregnant, so they will wait to see if they were wrong.  Great Whites typically have a gestation of 11 months and give birth to anywhere from 2 to 12 pups.  They will keep a close eye on Lydia to see if she really is going to give birth and hopefully they will learn even more about the habits of these sharks.

It is hoped that the sharks that have been tagged, which number close to 50 of different species will be able to give scientists a much better understanding of what their life really consists of.  The genetic material that has been collected as well should help them to follow breeding patterns and family trees for the sharks they have tagged already.  The oceans are vast and largely uncharted, so these projects will help in our understanding of our world and it's dwindling resources.

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