New tool helps oyster
growers prepare for changing ocean chemistry
By
Laura Newcomb
Oysters help clean dirty water |
For
Bill Mook, coastal acidification is one thing his oyster hatchery
cannot afford to ignore.
Mook
Sea Farm depends on seawater from the Gulf of Maine pumped into a Quonset
hut-style building where tiny oysters are grown in tanks.
Mook sells these tiny
oysters to other oyster farmers or transfers them to his oyster farm on the
Damariscotta River where they grow large enough to sell to restaurants and
markets on the East Coast.
The global ocean has soaked up one third of human-caused carbon dioxide (CO2) emissions since the start of the Industrial Era, increasing the CO2 and acidity of seawater. Increased seawater acidity reduces available carbonate, the building blocks used by shellfish to grow their shells.
Rain washing fertilizer and other nutrients into nearshore
waters can also increase ocean acidity.
Back
in 2013, Mook teamed up with fisherman-turned-oceanographer Joe Salisbury of
the University of New Hampshire to understand how changing seawater chemistry
may hamper the growth and survival of oysters in his hatchery and oyster farm.
Salisbury
and his team adapted and installed in the hatchery sophisticated technology
that Mook calls “the black box.”
Sensors housed inside a heavy black plastic
case the size of a breadbox estimate the amount of carbonate in seawater pumped
into the hatchery by measuring carbon dioxide and the alkalinity, or the
capacity of the water to buffer against increases in acidity.
The "black
box" was developed with funding from the NOAA’s
Ocean Acidification Program and Integrated Ocean Observing
System.
Mook
compares ocean acidification to a train barreling down the tracks headed for
his business. By measuring the year-to-year changes in carbonate and matching
that against how well his oysters do in a particular year, he says he’ll
understand how oysters grow under different conditions.
These tools help him
learn how fast and at what time the train may arrive.
“We
see a growth opportunity for this equipment,” Salisbury says.
He and his team
are now using “black boxes” in the waters off Puerto Rico to map where changes
in acidity may contribute to coral reef erosion.
Starting this year, NOAA
Ship Henry B. Bigelow will be outfitted with black
boxes to collect carbonate chemistry data during fisheries surveys along the
eastern seaboard.
NOAA will use this data to help improve predictions of how
ocean acidification may affect valuable resources and the people, like Mook,
whose livelihoods depend on them.
View
a short
video produced by the University of New Hampshire on the "black box" online.
Laura Newcomb is a Sea Grant Knauss Fellow at NOAA Research's Office of
Laboratories and Cooperative Institutes.
For
more information, please contact Monica Allen, director of public affairs at
NOAA Research, at 301-734-1123 or monica.allen@noaa.gov