KAPALUA — Canadian snowbirds Bob and Alexandra Kayser recently captured an uncommon sight on camera off D.T. Fleming Beach Park — a pair of green sea turtles apparently mating at the surface, The Maui News reported.

While not unique, good observations of green turtles mating are infrequent, said George Balazs, leader of the Marine Turtle Research Program at the Pacific Islands Fisheries Science Center of the National Marine Fisheries Service in Honolulu.

Balazs was excited to learn of such a sighting around Kapalua, because that is the area where Maui's most famous individual turtle, Maui Girl (aka 5690), hangs out during the nonbreeding season.

Since she regularly has dug nests in Lahaina in even-numbered years, Balazs is hoping that, "if she is still alive," she may do so again this year.

Almost all green sea turtles in Hawai'i travel to French Frigate Shoals to mate, but there is a small but growing population of turtles that nest here and, probably, also mate here.

Hawaiian monk seals get the attention, Balazs said, but "Maui is a very fascinating and exciting place for sea turtles."

If turtles are going to start mating in Maui waters, it could get exciting for snorkelers and divers, too. During breeding season — right now — "the males get a little wacky," Balazs says.

They will attempt to mount "any large object" in the water, including divers, according to one of the few scientific observations of green sea turtle mating.

That was done by Julie Booth in 1972 in Australia, and she learned that an amorous male can be fended off by adopting the same stance as a "not tonight, dear, I have a headache" female turtle: She stands erect in the water and splays out her limbs.

Really amorous males may have to be bitten — not by divers, but by lady turtles. Old males usually have plenty of scars on their heads from turn-downs.

"The female is completely in control of whether mating occurs or not," wrote Booth and co-author James Peters in their paper in Animal Behavior.

If a female sea turtle can't scare the male off, or shake him off, she can always crawl up on the beach.

The male has a somewhat tenuous grip on even a receptive female. He uses his claws to grasp her shell, and a recently mated female often shows scratch marks and bloody wounds from her tryst, which can take more than six hours.

In the courtship process, females can pick and choose their partners. They typically choose several different males. Rarely does a male get to mate with more than one female, apparently.

It's possible, according to the Caribbean Conservation Corp./Sea Turtle Survival League, that by having several fathers, the eggs in one nest could have a better overall survival chance, due to genetic diversity.

Balazs said just because a pair of turtles are getting cuddly in the water, as the Kaysers' pictures show, that does not prove sex is happening. Males will mount each other, too.

Booth observed mating at the surface, but also underwater and on the bottom of the bay at Fairfax Island in Australia.

Unless the Kaysers did it, no one is known to have observed Maui Girl mating, and although other turtles also are nesting around West Maui, that turtle, or those turtles, haven't been observed.

Skippy Hau of the state Division of Aquatic Resources and Glynnis Nakai of the federal Kealia Pond National Wildlife Sanctuary have counted and excavated nests around Waihee-Waiehu, but not much is known about that.

Maui Girl, on the other hand, comes right up in the tourist zone and has been photographed returning to the sea after digging a nest near Lahaina Shores.

She nests about half a dozen times in a good year.

More recently, said Balazs, she has moved a little bit north, nesting near Kamehameha Iki Park. He is a little concerned that the beach naupaka is growing out seaward there, which could reduce the nesting area.

He also worries about lights during nesting season — May to October or thereabouts, but in past even-numbered years, Lahaina businesses have cooperated in shielding lights that could lure the emerging babies in the wrong direction.

The hatchlings rely on the moon to orient themselves for the dangerous journey from the sand to the sea.

Balazs also recommends that swimmers and divers practice safe interspecies relationships and "be a little careful" when in the water with male green sea turtles at this time of year. They can't help themselves.

"It's the hormones."

For more Maui news, visit http://www.mauinews.com/default.aspx">The Maui News.