A Better Understanding of Coral Reef Ecosystems

Pelagic predators such as these barracuda, Sphyraena qenie, are part of the coral reef ecosystem in the U.S. Line Islands (NOAA Photo by Kevin Lino).
A team of scientists have embarked from Hawai'i on a three-month survey of coral reef ecosystems at Johnston Atoll, the U.S. Phoenix Islands, the islands of American Samoa, and the U.S. Line Islands in the tropical Pacific Ocean. The overarching objective is to better understand the coral reef ecosystems of these areas, many of which are seldom explored. The research expedition is part of a regular monitoring program, conducted by the Coral Reef Ecosystem Division (CRED), headquartered in Honolulu, Hawai'i. The expedition is supported by NOAA's Coral Reef Conservation Program and involves extensive cooperation among NOAA scientists and research partners, including the University of Hawaii Joint Institute for Marine and Atmospheric Research (JIMAR), the U.S. Fish and Wildlife Service, San Diego State University, and the Papahānaumaokuākea Marine National Monument.

The research expedition will be carried out from February 27 to May 24, 2012 aboard the NOAA ship Hi'ialakai. Under the leadership of Chief Scientists Dr. Jill Zamzow, Dr. Bernardo Vargas-Angél, and Jamison Gove, a diverse team of researchers will be conducting multidisciplinary coral reef ecosystem surveys, assessing the status of fishes, corals, algae, marine invertebrates, and the oceanographic conditions in which these organisms exist. The scientific data collected during the three-month research expedition will enable informed and effective implementation of ecosystem-based management and conservation strategies for coral reef ecosystems, helping to ensure their protection for generations to come.

Sunday, March 29, 2009

One fish, two fish – the Fish Team at Wake

As Fish Team divers, we’re often asked, “Isn’t it hard to count fish when there are so many swimming all around you?” When you’re just starting out, yes, it can be a bit overwhelming ― especially when there are fish of all sizes, shapes, and colors darting back and forth in front of you or above you or trying to hide in crevices or under rock ledges ― but with practice it becomes easier and easier. Having a transect line to follow and a defined area to count within also helps. Here Kaylyn McCoy records a school of black jacks (Caranx lugubris) swimming through her transect.

We’re also asked, “What’s your favorite part of your job?” For me, it’s being in the water with big animals, and I think the other fish team members would agree. Our time at Wake was especially rewarding because of the large number of bumphead parrotfish (Bolbometopon muricatum) seen on our dives. These strange-looking fish are normally rare elsewhere in the world, and definitely not seen in Hawaii, but here were seen in schools of up to 300 individuals.

Reaching sizes up to 130cm (almost 4 1/2 feet), these are the largest of the parrotfish, and like other parrotfish, it uses its beak-like teeth to scrape off algae or coral to eat. Bolbo (our nickname for this parrot) also uses its big, bumped head to ram into coral to break off smaller pieces to ingest.

I’ve been on over 1400 dives around 34 islands throughout the North and South Pacific and have seen some incredible underwater life, but being in the water with the bumpheads was truly an awe-inspiring, once-in-a-lifetime experience.

Bolbo was certainly the main attraction at Wake, but not the only big guys we saw. The humphead wrasses (Cheilinus undulatus), which can reach sizes up to 200cm (6 ½ feet) also made frequent appearances, though not in the same numbers as the bumpheads; usually we would see only one or two shyly swimming by.

Other big animals seen at Wake were gray reef sharks (Carcharhinus amblyrhynchos), which were observed either singly or in schools of up to 30. Another question commonly asked is “Aren’t you afraid of sharks?” My answer would be no, I’m actually more afraid of NOT seeing sharks, because a healthy shark population means that the rest of the fish population is healthy, and thus the reef ecosystem is in balance.

At Wake we definitely saw more sharks than we normally see in the Main Hawaiian Islands, but not as many as seen in the Northwest Hawaiian Islands, or in the Line Islands (Jarvis, Palmyra, and Kingman).

Regardless of how many sharks there are, seeing one always makes for a good photo opportunity.

But we don’t just count the big fish, we get all the smaller guys too, like this antenna turkeyfish (Pterois antennata), found lurking under a ledge…

…and this familiar face from Hawaii, the ornate butterflyfish (Chaetodon ornatissimus).

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