Hawaii humpback whale experts are reporting the sighting of a sickly humpback off Maui.

Hawaiian Islands Humpback Whale National Marine Sanctuary Superintendent Malia Chow said Friday the animal is emaciated and covered in whale lice. At least four sharks were following the whale.

She says these are all indicators of a whale in distress.

She says the whale isn’t entangled and doesn’t appear to have been struck by a vessel, and that the cause of its poor condition is a mystery.

Hawaii’s humpback whales normally spend their summers feeding in cold places like Alaska.

Chow says it’s not clear whether this whale is one of the first sightings of Hawaii’s upcoming whale season or if it stayed around from last season.

The whale was reported to sanctuary officials as being in distress off Olowalu, Maui, on Thursday by Blue Hawaiian Helicopters, which had been conducting a sedimentation and erosion survey with Department of Land and Natural Resources Chair Suzanne Case, the sanctuary said.

The Large Whale Response Network, West Maui Response team, U.S. Coast Guard and tour companies assisted with locating and monitoring the whale, the sanctuary said.

First sightings of humpback whales are typically in September or October, and they are generally in Hawaii from November through May. They breed, give birth and nurse their calves in Hawaii waters.

Humpbacks are protected under the Endangered Species Act and the Marine Mammal Protection Act. It is illegal to approach humpback whales closer than 100 yards in the water and 1,000 feet by aircraft.

The sanctuary, which is co-managed by the National Oceanic and Atmospheric Administration and the state’s Department of Land and Natural Resources, was designated to protect humpback whales and their habitat in Hawaii.

Anyone sighting a marine mammal in distress should report it to NOAA’s 24-hour hotline at 888-256-9840.