November 25, 2013 at 3:29 am #1303MikeKeymaster
Fish dying mysteriously
Friday, September 29, 2006 9:51 AM HST
Specimens sent to Oahu for analysis
By Carolyn Lucas
Scientists are baffled as to why several species of fish have been
discovered floating in the ocean in recent months.
There’s no obvious cause or discernible pattern to the low-level
die-off that has gone on about four months. Nevertheless, reports
continue to come in, said William Walsh, aquatic biologist for the
state Department of Land and Natural Resources, Aquatic Resources
The mysterious deaths have ranged over a large area including the
watersoff the Big Island, Maui, Molokai and Oahu.
Off the Big Island, the species affected include roi, Hawaiian grouper,
long-nose butterfly, yellow tang, lagoon triggerfish, goatfish, Moorish
idol, wrasse and bullethead parrotfish.
The species hit hardest is roi, or peacock grouper. It is one of the
fish species from Moorea introduced to Oahu and the Big Island in 1956
as a potential food fish for Hawaii residents.
A West Hawaii resident was the first to report seven roi found belly up
in the water with expanded swim bladders and bulging eyes on May 22.
The so-called “popeye effect” is sometimes thought to derive from
gas-bubble disease, caused by oversaturation of water with air.
Walsh, however, dismissed the possibility. He thinks the oversized eyes
suggest a fairly rapid ascent from deep water.
Aquatic Resources has found fewer than a dozen fish with the same
characteristics; three were still alive.
Walsh observed a bullethead parrotfish swimming upside down, spiraling
up and down, near death.
“It is kind of scary to see a fish struggling and in distress while
underwater,” he said. “It’s unnerving. You start to wonder whether this
is the beginning of something bigger. But it can also be something that
just passes through. We just don’t know.”
Fish were sent to the U.S. Geological Survey Hawaii Field Station on
Oahu, where pathologist Thierry Work analyzed them.
“Test results revealed no parasites,” Walsh said. “There was nothing
wrong with the fish, except they were dead.”
Work will conduct a tissue sample to investigate the cell structure of
To further the investigation, Walsh is asking the public to report any
suspicious fish die-offs, including the date, location, depth and any
behavior observed. If possible, chill recently dead fish and call the
Aquatic Resources Division at 974-6201 in Hilo, 327-6226 in
Kailua-Kona. For more information, call 327-6226
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