DIVERS COMPLETE FIRST SET OF CORAL TRANSECTS OFF DISAPPEARING ISLAND, FRENCH FRIGATE SHOALS

After over seven hours of transit from Necker Island this morning, coral and fish scientists were able to complete one set of transect dives off Disappearing Island at French Frigate Shoals. The dive is the first of over 20 dives that will be conducted over the next four days throughout the series of reefs and shoals of this nearly 200 square mile atoll.

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Of all the coral found today, researchers were pleased to see an abundance of acropora coral (above), a common type of table coral that is found throughout the majority of the tropical Pacific, except the main Hawaiian Islands.

According to the two coral biologists on the expedition, from what they've learned so far, this type of coral is almost entirely restricted to French Frigate Shoals and three other islands and atolls in the Northwestern Hawaiian Islands.

"Why this type of coral isn't commonly found in Hawaii may be due to the remote locations of the islands," said Jim Maragos, expedition lead investigator. "Coral colonies need a larvae source in order to establish and survive, and most of the Hawaiian islands may just be too cold and too far away from any such source. Acropora favors warmer temperatures and doesn't survive well in places which experience large waves and storms as the lower Hawaiian Islands do.

"At French Frigate Shoals the acropora may have become established from larvae that traveled in currents and eddies from Johnston Atoll, 450 miles to the Southwest. The larvae may have traveled in sufficient enough quantities to maintain a stable population here," Maragos explained.

According to Maragos, acropora was found 10 years ago at the Mana submerged barrier reef off the Na Pali Coast of Kauai. "However, because this type of coral may not be able to withstand the force of hurricanes, after Iniki struck in 1992 it isn't known whether or not the patch survived."

According to fish biologist Bill Walsh, "What comes with finding this coral is a wide variety of associated fish such as the chevron butterflyfish which feeds on the acropora. This fish is not usually found apart from acropora and is not found at all in the main Hawaiian Islands."

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