Two Hawaiian voyaging canoes, on an unprecedented voyage into the Western Pacific, were near the halfway point to Johnston Atoll, which they hope to use to confirm their position, and by Monday morning should be near a quarter of the way to their first stop, Majuro Atoll in the Marshall Islands.

The canoes had been moving at a leisurely 4 to 5 miles an hour during their first few days under way, but appeared to have dramatically picked up speed over the weekend.

While they were doing a little more than 100 miles a day at the start of the voyage, the canoes have gone significantly faster — based on automated position reports appearing to reach speeds of 6 and 7 miles an hour. But Sunday reports indicated their progress had slowed again.

Pacific weather imagery suggests the vessels would find stronger favorable winds as they dip south.

The canoes Hokule'a and Alingano Maisu, accompanied by escort Kama Hele, are navigating by noninstrument methods taught to Hawaiian voyagers by Micronesian master navigator Mau Piailug.

This voyage is a mission of gratitude, and the Hawaiian voyagers will present Piailug with the gift of the canoe Alingano Maisu, whose 54-foot hulls are taken from the mold of another Hawaiian voyaging canoe, the Hokualaka'i.

Hokule'a captain Bruce Blankenfeld is serving as the lead navigator until the canoes pass Johnston Atoll, after which Maisu navigator Chadd Paishon will take the lead. Blankenfeld, a trained noninstrument navigator, is a veteran Hawai'i waterman and an outrigger canoe paddling coach with Hui Nalu Canoe Club.

Ka'iulani Murphy, a crew member aboard Hokule'a and also a trained navigator, described the navigational plan in an e-mail to the Polynesian Voyaging Society Wednesday.

"With sunrise we headed 'Aina Kona, which we will sail until we get to 17 degrees north, then sail Komohana until we see Johnston Island," she wrote. "Bruce is keeping us on course using the sun and moon for direction."

In the star compass many Hawaiian navigators use, 'Aina Kona, sometimes written Kona 'Aina, is the direction west-southwest. Komohana is west.

The main Hawaiian Islands range from roughly 22 degrees north at Kaua'i to roughly 19 degrees north at Ka Lae or South Point on the Big Island. Johnston Atoll lies just below the 17-degree latitude.

Latitude, or distance from the equator, is comparatively easy for navigators to determine, particularly if they have clear skies. Murphy was saying that the canoe's plan was to reach the latitude of Johnston to the east of the island, and then sail directly down that latitude.

Theoretically, if the latitude is correctly determined, the canoes should not miss the atoll, although low islands like atolls are very difficult to spot, even from only a few miles away. Blankenfeld's plan takes the canoes on a line slightly north of Johnston. Even if they don't spot the island, they should be able to know they are nearby from its birds.

While many seabirds remain at sea for months at a time, a number of varieties of seabirds fly a known distance from their home islands each day for feeding, and return each night to their islands.

The noio, or noddy, flies as much as 40 miles from shore. The manu o ku, or fairy tern, can fly two or three times that far. Spotting either one is generally considered a reliable indicator that land is nearby.

While they're not seeing those birds yet, Blankenfeld in a radio report via satellite telephone on Friday said they had seen whales, and some other seabirds, including boobies and tropic-birds.

Reach Jan TenBruggencate at jant@honoluluadvertiser.com.