White terns enjoy growth with the help of humans

Published December 9, 2017 in the
“Ocean Watch” column, Honolulu Star-Advertiser ©2017 Susan Scott

White terns have taken to urban life, gracing trees between Hickam Air Force Base and Niu Valley. ©2017 Susan Scott

If visions of fairy terns dance in your head this month, they’re not holiday hallucinations. For the second year in a row, Honolulu’s white terns (the official name for what we once called fairy terns or angel terns) are having a banner year.

Fall isn’t usually a busy nesting season for seabirds, but then, Honolulu’s white terns aren’t your usual seabirds. These parents build no nest whatsoever, laying their egg and raising their hatchling on a bare branch.

After the first pair of white terns decided to raise a chick at Koko Head in 1961, others followed until today our island’s south side hosts about 2,300 and counting.

White terns are native throughout the world’s tropic and subtropics, including our Northwestern chain, but Oahu holds the honor of being the only main Hawaiian Island to host a breeding colony of white terns. So far, the birds prefer urban life, gracing trees between Hickam Air Force Base and Niu Valley.

In 2016 and 2017 white terns have had two bursts of egg laying, one in March and another in October. This is a change from the past when, after spring breeding, the birds took time off from chick raising until the next spring.

This is a couple, probably mated for life. ©2017 Susan Scott

No one knows whether this year-round breeding is the new norm here, but it’s encouraging that the charming beauties are so busy. The small fish and squid that white terns eat are apparently plentiful off the city, our towering trees are safe from most predators and people from all walks of life are interested in helping the birds.

The heart and soul of white tern support is Hui Manu-o-Ku, a grass-roots association of tern fans. Among other things, the hui works with researchers, public and private wildlife agencies, and businesses to highlight the tern’s whereabouts.

No one wants to harm these adorable bird families, but in addition, because white terns are protected by federal and state laws, disturbing them can incur a fine. So when eggs and chicks are teetering on bare branches, tree trimmers, landscapers and holiday light stringers want to know.

To call attention to nesting terns, volunteers from Hui Manu-o-Ku and its partners are tying light blue plastic ribbons bearing the organization’s phone number and website around the trunks of trees hosting white tern families.

Volunteers have flagged 85 trees since October 2016 and are enlisting citizen scientists to monitor the terns’ progress.

This is crucial because when the chick fledges, the flag must be removed to keep the system current. People working with trees have been cooperative, helpful and grateful for the heads-up.

How lucky we are to live in a city where real angels decorate our holiday trees. Volunteer to help keep eggs and chicks safe at whiteterns.org or call 379-7555.