11th ICRS Abstract book - Nova Southeastern University

3-17
The Effect Of Depressed Aragonite Saturation State On Larval Settlement, Post-
Settlement Survivorship, And Growth Of The Brooding Coral porites Astreoides
And The Broadcast-Spawning Coral montastrea Faveolata
Rebecca ALBRIGHT* 1 , Benjamin MASON 1 , Chris LANGDON 1
1 Rosenstiel School of Marine and Atmospheric Science, University of Miami, Miami, FL
Oral Mini-Symposium 3: Calcification and Coral Reef - Past and Future
In conjunction with the projected increases in pCO2 of the coming century, adult coral
growth and calcification are expected to decrease significantly. However, no published
studies have investigated the effect of elevated pCO2 on earlier life history stages of
corals. As coral recruitment, post-settlement survivorship, and growth are critical to reef
persistence and resilience, it is of timely importance to better understand the
repercussions on such factors. Larvae and gametes of Porites astreoides and Montastrea
faveolata (respectively) were collected from reefs in Key Largo, Florida, fertilized (M.
faveolata) and settled and reared in controlled saturation state seawater. The effect of
treatment water on settlement and post-settlement growth was examined. Three
treatment levels were targeted based on present (380 ppm) and projected pCO2 scenarios
for the years 2065 (560 ppm) and 2100 (720 ppm). Corresponding saturation states of
treatment water were obtained using 1M HCl additions: Ω = 3.19 ± 0.13 (control), 2.59 ±
0.08 (mid), and 2.16 ± 0.12 (low). Larvae were introduced to their respective treatments
and allowed one week to settle onto pre-conditioned limestone tiles. Percent settlement
was determined by examination under a dissecting microscope. Settled larvae were
placed in flow-through treatment aquaria (25°C) and growth rates were analyzed over the
course of twenty-one days, using high magnification photographs and SPOT©
Softwareto monitor changes in total surface area (mm2). Results indicate that saturation
state had no significant effect on percent settlement of P. astreoides or M. faveolata
larvae. Skeletal extension rates of P. astreoides spat exhibited a positive correlation with
saturation state, while tissue growth rates of M. faveolata spat were not significantly
affected.
3-18
Monitoring Oceanic And Coastal Variability in Carbonate Chemistry: Tracking
Ocean Acidification in The Greater Caribbean Region
Dwight GLEDHILL* 1 , R WANNINKHOF 2 , F.J. MILLERO 3 , C. M. EAKIN 4 , C.
LANGDON 3 , J. HENDEE 2 , T.R.L. CHRISTENSEN 1 , A.E. STRONG 4 , W.J.
SKIRVING 4 , J.A. MORGAN 1 , G. LIU 1 , S.F. HERON 4
1 IMSG at NOAA Coral Reef Watch, Silver Spring, MD, 2 NOAA OAR AOML, Miami,
FL, 3 Rosenstiel School, University of Miami, Miami, FL, 4 NOAA Coral Reef Watch,
Silver Spring, MD
The surface oceans serve as an important natural sink for increasing atmospheric carbon
dioxide (CO2) concentrations. As this CO2 reacts with seawater it reduces pH
(acidification) and redistributes inorganic carbon species. Ocean acidification decreases
the availability of carbonate ions that are vital to biocalcification processes, including
those of prominent reef building organisms. Mapping and monitoring the distribution of
such changes provides an important context for understanding the potential impacts of
ocean acidification and identifying the most susceptible regions. Using satellite remote
sensing and modeled environmental parameters, we have extended in situ observations
obtained from Volunteer Observing Ships (VOS) and multiple geochemical surveys to
derive estimates of the oceanic changes in sea surface carbonate chemistry throughout the
Greater Caribbean Region. The results reveal considerable spatial and temporal
variability throughout the region transposed over a strong secular decrease in aragonite
saturation state (Ωarg) at a rate of ~ -0.12 ± 0.01 Ωarg decade-1 (r2 = 0.97, P