Previous Ocean Watch columnOcean WatchNext Ocean Watch column

Monday, October 16, 2000

Frigate birds soar but
canít swim or walk

LAST week, a reader named Leland left me a phone message asking about a big bird he often sees near Magic Island.

When I called him, he said that he and his wife marvel at this solitary bird, which is all black except for a white patch on its chest. It has a wingspan of at least 5 feet and flies for hours without flapping its wings. Sometimes they watch it swoop deftly to the ocean's surface, then rise again to float on the wind.

Before I even returned the call, I knew this bird -- but not because I'm an expert at bird identification.

I, too, spend time around Magic Island, and I know that specific bird. This remarkable creature gracing the Ala Moana Beach Park area is a female great frigate bird.

It's easy to overestimate the size of animals in the distance but in this case, Leland's guess was short.

Hawaii's frigate birds have a wingspan of 7 feet.

Here's another amazing fact: These enormous birds weigh only about 3 pounds. This low body weight, combined with the huge wings and a forked tail (the bird's rudder), is what allows these seabirds to soar all day, nearly effortlessly, on thermal drafts.

Frigate birds do more than float in the air. These Thunderbirds of the avian world perform dramatic midair acrobatics such as stops, starts, twists and loops. But they pay a price for such aerial elegance: Frigate birds can't swim or walk. That means if they aren't flying or perched, they're in trouble.

WHEN I called Leland back, I told him frigate birds don't land on water because their feathers aren't waterproof. I was wrong. Of all Hawaii's seabirds, only sooty terns lack waterproof feathers. Frigate birds don't land on the water (or the ground) because their short legs and broad wings make it difficult, if not impossible, to take off.

Consequently, frigate birds must either pluck fish and squid from the water's surface or steal it from other seabirds.

Although frigate birds catch most of their own fish and squid, they occasionally use their exceptional flying skills to harass booby birds and shearwaters into regurgitating their food. Sometimes frigate birds do this in pairs or groups.

I once saw two frigate birds each grab a red-footed booby's leg in mid-air and flip it head over heels.

In the tumble, the booby bird dropped its fish and both frigate birds dove for it. They brawled over the food for a while, but it seemed more like a game than a fight.

In some parts of the world, frigate birds snatch up newly hatched sea turtles from the beach. For reasons unknown, this behavior is rare, if not absent, among Hawaii's frigate birds.

People have long recognized that frigate birds are occasional bandits. Their English name comes from the fast fighting ships, called frigates, used by pirates in the 18th and 19th centuries.

In Hawaiian, the bird's name is 'iwa, meaning thief.

In 1832, Protestant missionaries named the dormitory at their Waialua girls' school Hale'iwa.

After the school closed, a hotel built near the dorm's ruins adopted the name and eventually the community around it became known as Hale'iwa.

No one knows why the missionaries chose this name because frigate birds don't nest in the area nor do many soar near there.

But one does soar regularly at Magic Island, and like Leland and his wife, the sight of this enormous seabird hanging in the sky like a black kite always gives me a thrill. Cities just don't get better than this.

 

 


Marine biologist Susan Scott writes the newspaper column, "Ocean Watch",
for the Honolulu Star-Bulletin, www.starbulletin.com