Humpback whale rescues have increased to three so far in this November-May season in Hawaii, putting the number a little higher than normal.
Humpback whale rescue expert Ed Lyman said that although rescues have been as high as four, the usual number is two.
He said tour boats were the key in the latest rescue, that of a juvenile whale entangled in lines off Maui on Sunday.
"They stayed near the whale until a response team came. That makes a difference," Lyman said. Oftentimes a response team is unable to locate a distressed whale unless a boat stays near the animal.
The rescued juvenile whale was not one of the two humpbacks described as entangled in lines last week off Kauai and Olowalu, Maui.
In Sunday’s rescue, three vessels assisted the Hawaiian Humpback Whale National Marine Sanctuary’s response team.
At about 8 a.m. Sunday, the Pacific Whale Foundation’s vessel Ocean Discovery discovered that the humpback had a braided line in its mouth and was pulling ocean buoys. The juvenile was accompanied by an adult whale about six miles southwest of Lahaina.
The Ocean Discovery stayed near the whale until it was relieved by another private boat, Wiki Wahine, followed by the Aloha Kai, Lyman said. The response team arrived between 10 and 11 a.m. and was able to free the line from the whale’s mouth by 12:30 p.m.
Lyman said that using underwater cameras attached to a pole, the team was able to determine that a line ran through the mouth but that only one side had buoys attached. The response team added more buoys to that side, increasing the drag on the line and eventually pulling the line from the whale’s mouth. The team members knew they had succeeded when about 125 feet of line floated to the surface and the whale swam away.
Lyman said the line, braided twine cord, appeared to be a kind of fishing gear. "We still haven’t figured out what it is," he said.
Based on the whale’s relatively good condition, Lyman said, it appeared that the animal had not been entangled for a long time.
Two other whales rescued from entanglement this season included a calf whose lines were cut free off Lanai and an adult freed in waters near Lahaina.
The number of sightings in Hawaii waters of humpback whales entangled in fishing lines, nets and other marine debris has more than doubled during the current migration season, reaching a record high of 15. During the November 2012-May 2013 season, there were six sightings of entangled whales.
Their seasonal migration from Alaska brings an estimated 10,000 to 12,000 humpbacks to Hawaii — a large jump from the 1,000 estimated in 1978.