Advertisement - Click to support our sponsors.
Ocean Watch
By Susan Scott
Monday, December 25, 2000
What do shearwaters, wrasses, bristle worms and the Line Islands have in common? Each has a member in the Pacific Ocean named after Christmas. This wasn't just random naming, of course, and each got its name for a different reason. Christmas namesakes
roam the seaCaptain Cook started it. On December 24, 1777, he discovered an atoll in the middle of the Pacific, just 119 miles north of the equator. That's about 1,300 miles due south of Hawaii. In honor of the date, Cook named the place Christmas Island.
Today, Christmas Island is part of the Republic of Kiribati and is well worth visiting. With 140 square miles of land, it is the largest atoll island in the world.
By comparison, the combined landmass of all the islands in Hawaii's entire Northwest island chain is less than 6 square miles. Oahu, which is not an atoll, is 597 square miles.
Christmas Island is also the oldest atoll in the world, making its coral growth extraordinary. The fishing and scuba diving there are excellent, I'm told, and the island hosts several large seabird colonies.
Among those colonies are some dark-gray seabirds called Christmas shearwaters, named after the island. These birds, sometimes called Christmas Island shearwaters, also nest in small numbers Hawaii. Most go to the wildlife refuge of our northwest chain, but 40 to 60 pairs regularly nest on the Moku Manu Islands off the Mokapu Peninsula.
Christmas shearwaters are close relatives of our more familiar wedge-tailed shearwaters and make similar disconcerting sounds.
Once, while visiting a remote island in Hawaii's northwest chain, I volunteered to help a federal biologist band seabird chicks. We stopped at a small wooden box turned bottom up. A hole in the sand ran under one edge of the box.
"There's a Christmas shearwater chick in there," the worker told me. "Wait 'til you hear it." He lifted the edge of the box and gently picked up the fluffy black chick. "OH NO! OH NO! OH NO!" the chick shrieked over and over. We banded the little screamer and quickly put it back in its dark box where thankfully it shut up.
You don't have to go to remote islands to find the other Christmas critters. The Christmas wrasse is common on Hawaii's shallow reef flats and in surge zones. At night, these wrasses sometimes sleep in tide pools.
When you spot this 11-inch-long fish, it's easy to see where its festive name came from. The bulk of the body is red and green surrounded by splashes of yellow, blue and pink.
You will only see these lovely colors on large Christmas wrasses. When they're young, both males and females are a drab brown and green. As they mature, some of the females turn into males and it is only these sex-changed males that bear bright colors.
Other cheery Christmas animals decorating our coral reefs are Christmas tree worms. These worms burrow into living coral, usually lobe coral. Once inside, the worm builds a calcium carbonate tube as a permanent home.
The worm's soft body, which grows to just under two inches long, is safe inside this fortress of tube and coral.
To eat and breathe, each worm pokes out two colorful fanlike tentacles shaped like Christmas trees. These tiny trees can be yellow, orange, blue or tan and look like flowers blooming on coral heads.
Pass too closely, and the worm yanks its fans inside, closing its tube with a spiky trap door.
Christmas is not only in the air; it's in the water, too. Merry marine Christmas.
Marine science writer Susan Scott's Ocean Watch column
appears Mondays in the Star-Bulletin. Contact her at susanscott@hawaii.rr.com.
