Ocean Watch
By Susan Scott
Fairy tern is
Tinkerbell of seabirdsA Nuuanu reader writes: "For the past two years, I've been watching fairy terns flying in and out of Foster Botanical Gardens and Liliuokalani Garden. But all of a sudden they all disappeared. Where else could they be? Can you write more about their habits and habitats?"
My pleasure. This Tinkerbell of seabirds is the most common and, therefore, the most watched and loved seabird on Oahu. The reason for this is that humans have helped fairy terns (also called white terns) in Hawaii. Ironwood and other alien trees provide habitat space, attracting terns that would otherwise not be interested.
Oahu has its own resident population, and tree-filled Midway hosts thousands of these birds.
"If fairy terns are holy," writes one bird author, referring to how some indigenous people consider fairy terns sacred, "then Midway is heaven."
I would add Honolulu to that divine category because fairy tern nesting sites are scattered around the city. Watch for these fluttering white birds particularly around Kapiolani Park, Fort DeRussy and Iolani Palace.
One of the physical features that makes these seabirds so lovable is a ring of black feathers surrounding each dark blue eye. This gives the birds a wide-eyed, innocent look that can melt even the coldest heart.
Oddly, beneath their snow-white feathers, fairy tern skin is shiny black.
Fairy terns can fly distances when they need to, but they can also hover in one spot like, well, fairies. Since they're often curious and unafraid, fairy terns sometimes seek out and follow people, humming and twanging just above your head. I have been so visited by fairy terns on Midway and felt like I was in a Disney film.
Although they must come to land to reproduce, fairy terns are very much at home on the ocean. When they aren't mating or sitting on eggs or chicks, fairy terns are flying over the ocean's surface looking for fish.
Like puffins, fairy terns can catch several small fish in succession, line them up crosswise in their bills and feed them to their chicks one at a time.
Male and female fairy terns look identical, mate for life and live for 16 to 18 years. Mature birds live on the wing at sea until February when they journey to their breeding sites. Both partners choose a spot on a ledge or tree branch, and the female lays her egg there, bare, with no nest.
The male and female take turns incubating their egg. In places where there are few good places to lay eggs, only about 50 percent of eggs make it to fledging. On Oahu, where mature trees provide good egg-balancing spots, survival rate is 80 percent.
Both parents feed their chick until it can fly. Chicks take their first flight at about 7 weeks old, before they've lost all their down or fully grown their wings. They can fish on their own two weeks after that.
By September most fairy terns are finished with family chores for the year. On Oahu, however, some pairs stay year-round, nesting two or three times per year. The peak egg-laying time for Oahu terns is May and June.
As I wrote this column, my husband called from work. "What are you doing?" he asked.
"Writing about fairy terns," I said.
And then he said what everyone says at the mention of these birds: "I love those birds."
How could you not?
Marine science writer Susan Scott can be reached at http://www.susanscott.net.
