A 15-foot, 2,137-pound great white shark named Luna that started its journey from the Canadian coast in October 2018 is about to reach a new milestone. It is heading toward the southern tip of Florida from where it'll move to the northeast of the country to give birth.
Luna has been tracked for months by OCEARCH, a nonprofit that tags and tracks sharks. She was last pinged off Carolina’s coast near Charleston, 80-100 miles off the coast on May 9.
A ping happens when a great white shark’s dorsal fin breaks over the surface of the water and transmits a signal alerting its presence to a satellite which sends its geolocation to the tracking system, according to the OCEARCH.
“Two of the biggest sharks we are tracking right now pinged in today to let us know they are both off the coast of South Carolina. Fifteen-foot Luna is out over the Charleston Bump while 12’ 9” white shark Caroline is much closer to shore off Edisto Beach,” said a release by OCEARCH on their Facebook page.
Tagging Sharks
Sharks are tagged for scientific research. According to OCEARCH, each shark is provided with three different types of tags—Smart Position and Temperature (SPOT) tag, a Pop-off Archival Satellite Tag (PSAT), and an acoustic tag.SPOT tags are mounted on the dorsal fin and they transmit the geolocation of the shark whenever the giant pings over the surface. It’s battery operated and each battery lasts for over five years.
Acoustic tags that last for about 10 years are surgically implanted in the abdomen and they communicate a shark’s presence to receivers at the bottom of the sea up and down the coastline.
“PSAT tags record depth, temperature, and light levels (used for geolocation) and store the data to memory. The tags do not transmit any information while on the shark. They are instead programmed to detach from the shark six months to a year after attachment, float to the surface and transmit the data to us via satellite,” said the release.
How Do Sharks Become Mothers?
Sharks are fish that hatch from eggs. Depending upon how and where they lay their eggs, there are two types of shark mothers.White sharks are Viviparous sharks and their eggs hatch inside the uterus and the pups mature inside before they are given birth. The process of growth inside the uterus differs from species to species.
“Add on top of that the violent process of copulating in the first place and ultimately mother sharks have a huge toll taken on their bodies. For this reason, Dr. Montano says many sharks cycle every other year (dusky sharks cycle every 3 years) in order to allow their bodies to recover,” OCEARCH said in a post on its website.
The second type of shark mothers are oviparous. They lay eggs once they are ready but they don’t stick around to take care of them.
“The eggs have tendrils that attach to structures on the bottom of the seafloor such as coral, sponge or rocks that provide protection to the eggs. Once the baby shark inside the egg is developed, it hatches ready to defend itself with no mother to protect it,” explained OCEARCH.
