A badly entangled humpback whale, last seen Monday, is believed to have circled Hawaii island, but whale response crews have been unable to get to it to free it.

"It appears to be going counterclockwise around the Big Island," Ed Lyman, whale entanglement response coordinator for the Hawaiian Islands Humpback Whale National Marine Sanctuary, said Wednesday. "By now it’s made a complete circumnavigation of the Big Island."

Lyman said he hopes the whale on Thursday will be on the Kona Coast, where seas will be calmer and "more people, more eyes, more tour boats" will help find it. "It’s 45 feet long, but they’re like a big needle in a big haystack," he said.

The National Marine Fisheries Service and the marine sanctuary have been working together to get the word out to helicopter tour operators, whale researchers, boaters and other private citizens, including those on shore.

Lyman applauded their efforts to keep their eyes on the whale and take photos.

The fisheries service and the sanctuary are prepared to send crews to free the 45-ton gray mammal of the fishing gear trailing behind it, including a large red buoy that makes it easier to spot.

Lyman has gotten criticism from people, asking, "Why don’t you get out there?" But he said it is hard to intercept a whale, especially in remote areas and rough seas.

Well-meaning mariners are advised not to attempt cutting the line themselves, which could endanger them by snagging an outboard motor, and could leave "lethal wraps" behind, endangering other marine animals.

"We have a better chance with the buoy on it," he said.

The line is also used by crews to pull themselves closer to the whale, which appears to be in good shape and not in immediate danger of drowning.

The Coast Guard and state Department of Land and Natural Resources are also assisting.

On Friday, multiple sightings were made by two tour helicopter companies, Sunshine Helicopters and Blue Hawaiian Helicopters, along the Hamakua Coast.

On Saturday, windy and rainy weather hindered flying and boating. On Sunday, the whale was spotted moving fast down the Kona Coast, and was seen 30 miles south of Kailua-Kona. Late Monday, Lyman said they received reports of sightings off Kehena Beach in Puna. It was last seen later that day rounding Hawaii island’s easternmost point.

On Wednesday, a University of Hawaii at Hilo marine mammal professor and his graduate students went out, but made no sightings.

Anyone who spots the whale is asked to call the NOAA Marine Mammal Hotline at 888-256-9840.