HONOLULU (HawaiiNewsNow) - Wildlife officials are investigating a record number of humpback whale deaths in Hawaii this season.
Six humpback whale carcasses have washed up onto Hawaii shores since November. That's double the number typically found in a season, which runs from November to May. In winter, humpback whales travel from Alaska to breed and give birth in Hawaii waters.
The previous record for the number of whale carcasses found in Hawaii waters was in 2013, when five dead whales were found.
Biologists aren't sure what's behind the increase in deaths.
"It is higher than usual. It's almost double this early in the season for what we'd get in a whole season," said David Schofield, regional marine mammal response program coordinator.
The gruesome discoveries often prompt beach closures because of feasting sharks.
In November off Kailua Bay, the state hired a salvage boat to tow away a 60-foot long humpback whale carcass. Later that month, another carcass washed up on Yokohama Beach. This month, a dead whale was found off Maui.
Since November, whale carcasses have been scattered throughout the main Hawaiian islands -- one on Kauai, two on Oahu, two on Maui and one on Molokai.
Schofield said it's too early in the season to pinpoint what's causing the whales' deaths.
"If this trend continues where we go every week or so with a whale carcass then we might get concerned," He said. "It could be there was an early migration of whales and maybe some of them where not nutritionally capable of making that trip."
Each year 8,000 to 12,000 humpback whales migrate across the sea to Hawaii.
Biologists are investigating to see if the whales starved or if there's a problem with the ocean's health that put these whales in harm's way.
The six whale carcasses were too decomposed for biologists to do necropsies, but officials will be meeting with partners in Alaska and Washington D.C. to investigate further.
If you see a dead or stranded whale, you are urged to call the Marine Mammal Hotline at 888-256-9840.