Widespread mortality of Thalassia testudinum was first documented in Florida Bay, USA, during the summer of 1987. This unprecedented event spanned 3 yr, affected 40 km 2 of seagrass and resulted in more than a decade of ecological disturbances. Initial putative causes for seagrass die-off ranged from climatic anomalies and watershed changes to wasting disease and eutrophication. Subsequent experimental research suggested that hypoxic plant tissue, caused by low water column oxygen content or reduced photosynthesis, allowed intrusion of sulfide leading to plant death. Contributing factors included high temperatures, salinities and T. testudinum biomass, together causing lower oxygen water solubility, higher community respiration rates and elevated nighttime oxygen demand. The Fisheries Habitat Assessment Program (FHAP) has tracked the system's slow recovery since 1995. Recent FHAP data (2012) indicated that T. testudinum had returned to pre-die-off densities in even the most severely affected locations. During the summer of 2015, following several months of drought, National Park Service researchers reported hypersaline conditions and a recurrence of seagrass die-off in north-central Florida Bay. An interagency effort is presently underway to document the duration, extent, impacts and possible factors responsible for the current mortality. Initial field surveys indicate that there is high spatial coincidence between the current and the 1987−1990 events and that hypersalinity, water column stratification and bottom-water anoxia might have once again resulted in mass mortality of T. testudinum in Florida Bay. The goal of this report is to alert the scientific community to the recurrence of this important ecological event.

of changing pCO 2 on species interactions is crucial to adequately predict ecosystem-level responses in the future.

Bay scallop Argopecten irradians irradians populations and fisheries in the Peconic Bays of eastern Long Island, New York, USA, were decimated by brown tide algal blooms between 1985 and 1995. Despite the absence of brown tide since 1995, populations did not recover on their own over the next 11 yr. We hypothesized that this was due to recruitment limitation and initiated an intensive restoration program to jump-start populations by planting several million hatchery-reared scallops at high densities to ensure high fertilization success and boost larval supply. We observed 11-to 32-fold increases in larval recruitment in different embayments by 2010, compared to the period 2005 to 2006 (before intensive restoration); the most dramatic increase (3239%) occurred in Orient Harbor, the focus of restoration efforts. Recruitment was highly correlated with our index of total fertilized egg production in Orient Harbor and Hallock Bay, but not in 2 other embayments-where larval export or population overestimation probably compromised the correlation. Resurgent recruitment following restoration was not correlated to coincidental changes in adult fecundity, water temperature, salinity, rainfall, chlorophyll a, total particulate nitrogen, or local winds; decreased planktonic predation and allochthonous larval infusion were deemed unlikely drivers. We conclude that Peconic bay scallops were recruitment-limited following the 1995 brown tide and that resurgent recruitment was driven, initially, by our intensive restoration efforts and later by the rebuilding natural populations. Sustained restoration, conducted with high scallop numbers/densities, may help boost natural populations above threshold levels at which they become self-sustaining.

Ocean acidification will disproportionately impact the growth of calcifying organisms in coral reef ecosystems. Simultaneously, sponge bioerosion rates have been shown to increase as seawater pH decreases. We conducted a 20-week experiment that included a 4-week acclimation period with a high number of replicate tanks and a fully orthogonal design with two levels of temperature (ambient and +1 °C), three levels of pH (8.1, 7.8, and 7.6), and two levels of boring sponge (Cliona varians, present and absent) to account for differences in sponge attachment and carbonate change for both living and dead coral substrate (Porites furcata). Net coral calcification, net dissolution/bioerosion, coral and sponge survival, sponge attachment, and sponge symbiont health were evaluated. Additionally, we used the empirical data from the experiment to develop a stochastic simulation of carbonate change for small coral clusters (i.e., simulated reefs). Our findings suggest differential impacts of temperature, pH and sponge presence for living and dead corals. Net coral calcification (mg CaCO3  cm(-2)  day(-1) ) was significantly reduced in treatments with increased temperature (+1 °C) and when sponges were present; acidification had no significant effect on coral calcification. Net dissolution of dead coral was primarily driven by pH, regardless of sponge presence or seawater temperature. A reevaluation of the current paradigm of coral carbonate change under future acidification and warming scenarios should include ecologically relevant timescales, species interactions, and community organization to more accurately predict ecosystem-level response to future conditions.

Intensive efforts to restore bay scallop Argopecten irradians irradians populations and fisheries in the Peconic Bays of eastern Long Island, New York, USA, were begun in 2006, following a 12 yr period during which commercial fishery landings averaged 1 to 2% of historical levels seen prior to 1985 to 1995 brown tide algal blooms. Compared to 2005 to 2006, natural population densities of 0+ yr scallops in fall increased 16 × by 2007 in Orient Harbor (OH), the focus of our restoration efforts; by 2009, densities in OH and other, unplanted, embayments had increased by 110 × and up to 331 ×, respectively. Spatial and temporal patterns paralleled those documented for larval recruitment; highly significant correlations between commercial harvest levels and both baywide larval settlement and juvenile benthic densities were revealed. Official fishery landings were 13 × those of pre-restoration levels by 2010 and have remained relatively stable through 2013. Following commencement of restoration, dockside revenues and economic benefit to the regional economy have increased by ~US$2 million and $20 million, respectively; our calculations suggest that these figures are 40% of actual numbers. Population resurgence is not correlated to temporal changes in predator populations or submerged aquatic vegetation cover. We conclude that rebuilding of Peconic bay scallop populations and fisheries has been driven by dramatic increases in bay scallop larval supply emanating from our intensive restoration efforts. By definition, we cannot say that Peconic bay scallops have attained an alternate stable state, but it is clear that dramatic increases in populations, fishery landings, and economic value are possible in just a few years.