New York, May 29 : Marine authorities have detected four great white sharks swimming in the waters off New York and New Jersey. According to OCEARCH, a global nonprofit marine research group which provides open-source data about shark migration, recently recorded four male great white sharks around the coasts of the two states, CNN reported on Sunday. The organization places electronic trackers on each shark that "ping" when the shark breaks the surface of the water, allowing researchers to track their annual migration and movement patterns. Simon, a 9-foot long 434 pound juvenile great white, pinged off Fire Island on May 2, according to OCEARCH's website. He had traveled 1,520 miles over the past 105 days, says the nonprofir. Jekyll, another juvenile who weighs 395 pounds and is 8 feet 8 inches long, pinged on May 15 off Long Island. The shark has travelled 1,595 miles over the past 102 days. Jekyll was joined by Keji, another juvenile weighing almost 600 pounds and reaching over 9.5 feet in length, who pinged on May 17. Keji has travelled 7,697 miles over the past 368 days, according to OCEARCH. On May 21, Frosty, a juvenile weighing in at 393 pounds and measuring 9 feet 2 inches long, also pinged off the coast of Rhode Island. The four sharks all appear to be making their annual migration from the Florida Keys up to the US Northeast and Canada, according to OCEARCH's data. /IANS