Hawaiian voyaging canoes continued Tuesday to struggle against what Hokule'a physician Ben Tamura called "these unforgiving southwest winds."

The National Weather Service doesn't expect the winds for the canoes to change to trades until Thursday or Friday.

Hokule'a and Alingano Maisu and escort boat Kama Hele tacked without gaining ground through most of Monday, but appeared to be making some headway on a starboard tack through the first half of Tuesday. The ability to make progress may be associated with the reduced size of the 20-foot northwest swell that had been plaguing the canoes. Messages from Hokule'a and from escort boat Kama Hele indicated the swell had dropped by about half and was shifting from northwesterly to northerly.

The canoes had delayed their departure in part to avoid bad weather, but recognized that once they were at sea, they would have to deal with what came.

Crew member Ka'iulani Murphy, in an e-mail Tuesday, said that message has come home.

"We have experienced a good lesson in deep-sea voyaging with the weather we have been in. Before you leave, you plan around meteorological models, but out here, it's a matter of what you truly have to deal with. It is a good reminder and process in being prepared for everything," she wrote.

But there are spirit-lifting features about the open sea, and among them are the seabirds. A few days ago, a line of 'a or boobies perched at the stern of Hokule'a, and Murphy said crew members saw a koa'e kea or white-tailed tropicbird, and another 'a.

Murphy said the crew members have been practicing a song written for the canoe Alingano Maisu, and that crew member Attwood "Maka" Makanani was teaching members Palani Wright and Kaleo Wong to play guitar.

Escort boat Kama Hele's captain, Mike Taylor, reported that large swells and the canoes maintaining more distance from each other have made it difficult for the canoes to keep track of each other at night with just their navigational lights. Captain Shorty Bertelmann on Maisu turned on a light at the top of the canoe's mast, which made it easier to spot the vessel.

"An unremarkable but good safe night of sailing," Taylor said of Monday night and Tuesday morning.

The canoes for three days have been about midway between the Big Island and Johnston Atoll, the tiny island they hope to spot to confirm their positions. Both canoes are sailing by traditional non-instrument methods.

Murphy said that the canoes sailed Monday night and Tuesday morning on a southerly course, part of the night hema or dead south and part of the night haka malanai, or south-southeast. The terms are taken from the Hawaiian star compass developed by non-instrument navigator Nainoa Thompson.

She said the moon is an important feature of navigating by non-instrument means. The moon was to rise Tuesday between the constellations of Gemini and Cancer.

As of late Tuesday afternoon, the canoes were near the latitude of Johnston Atoll, but still close to 400 miles from it. Latitude is the distance from the equator. The canoes yesterday afternoon were several days sailing away but almost directly east of Johnston, which they hope to sight as an opportunity to confirm their position on the long sail from the Big Island to Majuro in the Marshall Islands.

Reach Jan TenBruggencate at jant@honoluluadvertiser.com.