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Reef restoration programs in Florida, US, focused initially on Acropora, but there is now a need to include other species that have also experienced declines. An outplanting experiment using Acropora cervicornis, Montastraea cavernosa, and Orbicella faveolata was conducted to compare performance among species and evaluate the impacts of contact interactions with macroalgae and the zoanthid Palythoa caribaeorum. Montastraea cavernosa and O. faveolata showed high survivorship (78% and 92%, respectively) over 18 mo. However, surviving colonies had limited growth and lost tissue due to factors like predation and disease. In contrast, A. cervicornis showed exponential growth. Colonies in contact with macroalgae showed the lowest survivorship. Removing macroalgae provided no long-term benefits in growth and a slight improvement in colony survivorship. Acropora cervicornis in contact with Palythoa grew 45% less than controls. Our study showed that: (1) coral taxa with massive morphologies (40–130 cm2) can be transplanted with low colony mortality but that their slow growth is not enough to balance partial tissue mortality caused by multiple chronic stressors; (2) removal of macroalgae at the time of outplanting improves colony survivorship; (3) periodic removal of macroalgae does not enhance growth; and (4) contact with Palythoa should be avoided. The impacts of contact competition were variable among species with different colony morphologies, with A. cervicornis showing the highest susceptibility to competition from algae and Palythoa. While restoration can rapidly increase coral abundance, long-term success will require a multifaceted approach to reduce the impacts of chronic reef stressors on wild and outplanted corals alike.

Hurricanes are important ecological disturbances that maintain biodiversity. We investigated the short-term impacts of Hurricane Irma, a category 4 storm that passed through south Florida on September 10, 2017, on fish and macroinvertebrate communities of western and north-central Florida Bay, FL, USA. Spatiotemporal trends in physical water conditions (temperature, salinity, water depth, dissolved oxygen, chlorophyll a, and turbidity) as well as rainfall and coastal discharge were assessed to characterize hurricane-induced habitat changes. Dramatic but ephemeral changes in water depth and rainfall were observed. Longer lasting reductions of salinity regime and increases in turbidity and chlorophyll a were also observed. The prevailing hypersalinity (≥ 40 ppt) conditions, ongoing since March 2017, were abruptly ended by the storm. Hurricane Irma significantly altered fish and macroinvertebrate communities. Analysis of community spatiotemporal trends revealed spatially distinct temporal community shifts. Cluster analysis distinguished four groups among nine highly abundant species identified as exerting the most influence on pre- and post-hurricane total community differences. Reductions in relative abundance of two groups were coincident with Irma’s passage while a third group, comprised solely of pelagic, zooplanktivorous Anchoa mitchilli, exhibited rapid population growth that started 2 months after the passage of the storm. These faunal disruptions are reminiscent of a prior Florida Bay community shift that followed a similar sequence of consecutive disturbances: hypersalinity, seagrass die-off, and a category-5 hurricane. Recovery from this prior community shift cascade took many years.

The pink shrimp (Farfantepenaeus duorarum) has been selected as an ecological indicator to assess ecological effects on estuaries of implementation of the Comprehensive Everglades Restoration Plan that seeks to restore historical freshwater flows and nearshore salinity regimes in southern Florida. Concern over altered freshwater delivery impacts on pink shrimp productivity was expressed as early as the 1960s. The present review assessed pink shrimp scientific literature of the past 75+ years (>500 publications) to glean information relevant to understanding potential influence of freshwater management on pink shrimp productivity. The review was organized around “Essential Fish Habitat” metrics concerning abundance, growth, survival, distribution, productivity, and behavior. It summarizes previous pink shrimp field, laboratory, and modeling studies. Where possible, statistical analyses and meta-analyses of previously published data were performed to investigate consistency among independent findings. Pink shrimp occur in a wide range of salinities (0.5–67 ppt). A majority of studies (53.3%) reported maximal abundance between ∼20 to 35 ppt salinities. One laboratory study reported maximal growth at 30 ppt. Meta-analysis of reported growth rates did not yield results due to non-convergence of regression models. Reported survival was maximal at ∼30 ppt and remained high (>80% survival) across salinities of ∼15 to 40 ppt. A regression model that combined survival data across studies confirmed a previously reported parabolic relationship between salinity and survival; in this regression, 35 ppt maximized survival. Productivity, conditional upon survival and growth, was maximized at polyhaline (18–30 ppt) conditions. Inshore hypersalinity (>40 ppt) may elicit young pink shrimp behavioral cues counterproductive to settlement in nearshore areas. Virtually no information exists regarding postlarval pink shrimp movement or preference relative to salinity gradients. Realization and preservation of nearshore polyhaline conditions and elimination of hypersalinity should maximize growth, survival, and density, thus improving pink shrimp productivity. New and updated statistical models predicting pink shrimp distribution, abundance, growth, survival, and productivity relative to salinity conditions are needed to better guide freshwater management decisions.

The pink shrimp Farfantepenaeus duorarum (Burkenroad) lives in south Florida ecosystems in different salinity regimes ranging from brackish to hypersaline. In Florida Bay, the main nursery grounds, juveniles reside in 25–50 salinity; while 20 km northwest of the Bay, juveniles inhabit more estuarine salinities between 5 and 15. In this study we investigated the hypothesis that the disparate salinity regimes in which pink shrimp juveniles reside may be due to a non-genetic resistance adaptation to different acclimation salinities in their respective nursery habitats during postlarval development when the maximum tolerance to salinity occurs. To test this hypothesis and to define salinity tolerances during ontogenetic development, salinity trials were conducted with four postlarval ages (PL 15, PL 25, PL 35 and PL 55) previously acclimated in two salinities (15 and 35) and then exposed to an abrupt salinity change for 96 h at 27.5 ± 0.5 °C. Results indicated that the degree of tolerance to salinity varies with ontogenetic development. Regardless of acclimation salinity, two clearly distinguishable salinity tolerance ages were discernable. Postlarvae of age PL 35 and PL 55 exhibited significantly higher average survival than at an age of PL 15 and PL 25. This result suggests that postlarvae between 25 and 35 d old may complete development of osmoregulatory capabilities to cope with abrupt changes in salinity, which concurs with the age at which planktonic postlarvae settle on the sea-grass banks of Florida Bay. Results regarding salinity tolerances in the two acclimation salinity groups demonstrated that postlarvae acclimated in a salinity of 15 tolerated salinities 20 units lower than those acclimated in regular 35 sea water salinity. The high survival of postlarvae recorded at salinities between 2 and 15 after a long acclimation period at a salinity of 15 suggested that non-genetic resistance adaptation (acclimation) had taken place during development, supporting our hypothesis that a preconditioning salinity during postlarval development may modify the subsequent tolerance limits of juvenile stages.