Montana ecologist Oscar “Wally” Johnson and writer Susan Scott are busy putting the final touches on  their new book called “Hawai’i’s Kōlea: The Amazing Transpacific Life of the Pacific Golden Plover, ” expected in print in November.

The book will be the first biology guide for laymen about the Pacific golden plovers in Hawaii and their nesting grounds in Alaska.

Johnson is on Oahu this week to give a talk Thursday night about new data he has gathered after attaching lightweight radio packs to some of the birds to trace their migration patterns by satellite.

Pacific golden plovers
Pacific golden plovers weigh 7-8 ounces when they begin their non-stop flight and about 4 ounces when they finish. Courtesy of Wally Johnson

In the 30 years Johnson has been coming here to study plovers, he has become kind of a rock star to ploverphiles who feel they have a personal relationship with this spindly legged shorebird.

Ancient Hawaiians who hunted the bird with snares called it the kōlea.

The birds’ biggest fans are people who have kōlea hanging around as wildlife visitors on their driveways or in their backyards for about seven months each year.

Islanders also enjoy watching the kōlea on golf courses or darting between headstones at island cemeteries or on school grounds  — anyplace with grassy flat ground.

We have a kōlea traveler at our house every year I named “Goldie.” She seems to find a lot of insects to eat in the grass surrounding the concrete pavers on our driveway.

Adult plovers come from their breeding grounds in western Alaska to Hawaii annually in late August to early September. The juveniles arrive later, landing here up until November.

The birds always return to their exact same location in Hawaii, which they guard with a ferocity that is astounding for a creature weighing only about four ounces upon arrival.

Most of Hawaii’s kōlea depart the islands to return to their breeding grounds April 25 or a few days before or after.

Montana ecologist Oscar "Wally" Johnson with a Pacific golden plover.
Montana ecologist Oscar “Wally” Johnson with a Pacific golden plover. He will speak in Honolulu on Thursday night. Courtesy of Wally Johnson

What is astounding about Goldie and other Pacific golden glovers is they fly to Hawaii from Alaska across the Pacific Ocean non-stop. And fly back the same route non-stop.

That means the kōlea is in constant motion on each trip for 72 to 96  hours as it traverses 3,000 miles over the open ocean.

Johnson told me in a phone interview he had discovered with his latest satellite tracking study that one of the plovers leaving Alaska had completely bypassed Hawaii and flew as far as Okinawa, where it stayed for about a month before heading non-stop to Sulawesi in Indonesia.

“That’s significant because until now we have not seen a plover in Indonesia. We haven’t published anything about it yet, “ he says.

For his latest study, he outfitted 10 birds with satellite trackers but he received tracking information from only three of the birds, including the long-distance flyer, which made it to Indonesia.

The information is collected by the Argos satellite uplink and then retrieved by Johnson from an intermediary agency.

Johnson says he’s not sure what happened to the transmitters attached to the other seven birds. He says the birds could have died in bad weather or their transmitters might have failed.

Information from the other two birds he was able to track showed they flew the normal pattern, directly from Hawaii to Alaska and back to Hawaii again.

A male Pacific golden plover with breeding plumage — and leg bands.
A male Pacific golden plover with breeding plumage — and identification bands attached to his legs. This particular bird lived to be 21 — the oldest the researchers are aware of. Most live to age 5 or 6. Courtesy of Wally Johnson

In earlier research, using geo-locators in bands attached to the birds’ legs, Johnson and fellow researchers discovered more precise information about the range of the plovers’ nesting grounds in Alaska and the different locations they visit once they leave Alaska.

The geo-locator records sunlight levels at various intervals, which allows the bird to be tracked as it migrates.

Geo-locator studies confirmed that one group of plovers flies directly to Hawaii, faithfully returning to the same spots each year — and then flies directly back to Alaska to breed.

Another group nests farther north in Alaska than the Hawaii group. And it takes a different route south, bypassing Hawaii completely and heading non-stop to winter in the central and south Pacific.

This contingent has individuals who stop off in places like the Marshall Islands, Samoa, Fiji, Vanuatu and as far away as Queensland, Australia. Australia is the farthest place a Pacific golden plover has been found to reach non-stop.

It is incredible to think that such a small bird can fly without resting to such distant locations as Samoa and Australia. That means flying up to 8,000 miles over seven or eight consecutive days.

Pacific golden plover flight routes.
By attaching geo-locators to plovers, researchers determined that some bypass Hawaii on a three-stop route (yellow arrows). Courtesy of Wally Johnson

Johnson says with geo-locators, researchers learned that the plovers that bypass Hawaii follow a circular migration route, first going south into the central Pacific and then on their way back to Alaska,  stopping off in Japan to fatten up for about a month in the rice fields of Honshu Island before continuing on to their breeding grounds in the Alaska tundra or Siberia.

Johnson says he is looking forward to doing additional research next year with new, even lighter-weight satellite GPS tracing devices that are extremely accurate, providing data that can be directly downloaded onto mobile phones or home computers.

What’s still a mystery is how the kōlea figure out how to travel to the exact same wintering spots each year.

Johnson says, “We are still not sure, but they may have a compass built into their brains that can pick up magnetic fields or maybe they follow cloud or star patterns or pick up surf sounds. “They are certainly good navigators. That’s for sure.”

He says many of the juveniles flying to Hawaii for the first time don’t make it. Their mortality rate could be as high as 80 percent.

Another mystery is how the birds know when it is time to leave Hawaii to return to Alaska.

“There appears to be kind of an internal clock in their brains that gives them the signal to go. We still don’t understand it but that’s a likely explanation,” says Johnson.

One thing that’s clear is the birds get very fat before they leave. When the kōlea take off next month they will weigh six to seven ounces, almost double what they weighed when they touched down in Hawaii.

They need the weight for the huge amount of energy they will expend on the open-ocean flight, during which they are unable to glide or land on water or eat or drink anything.

They fly about 40 mph, with much faster bursts when assisted by tailwinds.

Some well-meaning friends of the kōlea try to fatten them up for the trip to Alaska by giving them human food such as sushi, French fries and corn chips.

Johnson says this won’t drastically harm the birds, but he says if you are compelled to feed a kōlea, give it the protein it needs for strength for its long flight to Alaska.  He suggests small pieces of a hard-boiled egg or mealworms.

Johnson’s talk “Kōlea Biology Update 2016” will be from  7 to 8:30 p.m. Thursday in the Hawaii Room of the Neil Blaisdell Center. The free talk is sponsored by the Hawaii Audubon Society.

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