A great white shark, which mysteriously disappeared more than a year ago, reappeared off the US East Coast shortly before the presidential elections.
Since May 2019, researchers no longer know where the shark, known as Katherine, is. They received a weak signal from their tracking device in April this year, but have only now received enough data to confirm her identity and whereabouts.
Katherine was tagged in August 2013 by the marine monitoring organization OCEARCH and was closely monitored for the next five years. Her movements have helped researchers better understand how female great whites move in the North Atlantic, possibly during three pregnancy cycles, OCEARCH said.
Katharine is alive and well! Marked in August 13th â13, & she still gives us her whereabouts more than 7 years later. “This is a record for our Atlantic SPOT tags, which usually only send us data about great white sharks for about 5 years,” said Dr. Bryan Franks of @JacksonvilleU #FactsOverFear pic.twitter.com/MLq3fkHZR2
– OCEARCH (@OCEARCH) October 31, 2020
The non-profit organization tracks great whites by equipping them with devices that “ping” when a shark breaks through the surface and send location data to the team via satellite. These devices usually last for about five years, and after Katherine’s tracker didn’t ping for about a year, people thought they would never hear from her again.
However, in April, a short and inconclusive ping, called a “Z-Ping,” came from her tracker. OCEARCH said that the shark’s device apparently sent out a signal, but not long enough to confirm that it was her.
“Basically, the [tracker]sends a signal to the satellite, but it’s not strong enough to transmit all the data necessary to determine a location for the animal,” the organization said in a statement.
On October 31, several strong signals were recorded by Katherine’s tracker, which took her into the deep North Atlantic, hundreds of miles off the east coast of the United States.
“This is a record for our Atlantic SPOT tags, which normally only send us data on great white sharks for about five years”. Bryan Franks, who is Assistant Professor of Biology/Marine Sciences at Jacksonville University and is working with OCEARCH, said in a statement “Katharine latched on several times yesterday and confirmed that it was no accident.”
OCEARCH said it was “very unusual” to get back data on a shark over such a long period of time and that Katherine will provide valuable insight into the lives of other great whites in the region.
“Katherine showed movement patterns that indicate she is a mature female [great white shark], with trips to the open sea during some winters,” the OCEARCH statement said. “Her tracks over the past seven years along the coast from Cape Cod to Florida and with long forays to the Grand Banks of Newfoundland, the eastern Gulf of Mexico and the Atlantic Ocean off shore could include the movements of two or three pregnancy and birth cycles of her pups.
“She has already delivered an incredible data set of more than 1,700 locations covering 37,000 miles of ocean since the day she was tagged. It will be fascinating to see where her next steps might be”.
Katharine has already provided an incredible data set of more than 1,700 locations covering 37,000 miles of ocean since the day she was tagged. Her movement patterns suggest that she is a sexually mature female that spends some winters on the open ocean as a #white shark. pic.twitter.com/zz8htbBu4D
– OCEARCH (@OCEARCH) October 31, 2020
When she was marked, Katherine was an undergrown 14-foot and two inches long. It is believed that she may have grown considerably since then.
“It has been seven years. One of the things we don’t understand is the rate of growth when they reach this size,” OCEARCH founder Chris Fischer told the Miami Herald in April.
“It will be bigger, significantly bigger and most importantly, much, much bigger. When they grow to over 12 feet, they begin to grow in girth and body weight. The volume increases quite dramatically. She is probably a very robust, mature female great white shark in her productive flowering period”.