The biotic integrity of the Florida Everglades, a wetland of immense international importance, is threatened as a result of decades of human manipulation for drainage and development. Past management of the system only exacerbated the problems associated with nutrient enrichment and disruption of regional hydrology. The Comprehensive Everglades Restoration Plan (CERP) now being implemented by Federal and State governments is an attempt to strike a balance between the needs of the environment with the complex management of water and the seemingly unbridled economic growth of southern Florida. CERP is expected to reverse negative environmental trends by “getting the water right”, but successful Everglades restoration will require both geochemical and hydrologic intervention on a massive scale. This will produce ecological trade‐offs and will require new and innovative scientific measures to (1) reduce total phosphorus concentrations within the remaining marsh to 10 µg/L or lower; (2) quantify and link ecological benefits to the restoration of depths, hydroperiods, and flow velocities; and (3) compensate for ecological, economic, and hydrologic uncertainties in the CERP through adaptive management.

Diffuse phosphorus pollution is commonly remediated by diverting runoff through treatment wetlands to sequester phosphorus into soil layers. Much of the sequestered phosphorus occurs in organic forms, yet our understanding of its chemical nature is limited. We used NaOH-EDTA extraction and solution 31P NMR spectroscopy to speciate organic phosphorus sequestered in a large treatment wetland (STA-1W) in Florida, USA. The wetland was constructed on previously farmed peat and was designed to remove phosphorus from agricultural runoff prior to discharge into the Everglades. Unconsolidated benthic floc that had accumulated during the 9-year operation of the wetland was sampled along transects through two connected cells dominated by cattail (Typha dominigensis Pers.) and an additional cell colonized by submerged aquatic vegetation, including southern water nymph (Najas guadalupensis(Spreng.) Magnus) and coontail (Ceratophyllum demersum L.). Organic phosphorus was a greater proportion of the sequestered phosphorus in the cattail marsh compared to the submerged aquatic vegetation wetland, but occurred almost exclusively as phosphate diesters and their alkaline hydrolysis products. Itwas therefore markedly different from the organic phosphorus in mineral soils, which is dominated typically by inositol phosphates. Phosphate diesters are readily degradable in most soils, raising concern about the long-term fate of organic phosphorus in treatment wetlands. Further studies are now necessaryto assess the stability of the sequestered organic phosphorus in response to biogeochemical and hydrological perturbation.

Understanding how and why animals are distributed through time and space has always been a fundamental component of ecology and is an essential prerequisite for effective conservation and/or management. However, for highly mobile K-selected species, behavioural predictability is rarely considered over appropriate scales relative to life history. To address this point, a multidisciplinary approach combining telemetry, external tagging, physical assessment, environmental monitoring and genetic analysis was adopted to determine a spatial framework for the movements of adult lemon sharks Negaprion brevirostris at multiple spatial and temporal scales from 2007 to 2011. Lemon sharks (n = 83) were tracked with passive acoustic telemetry, revealing a winter residency in the southeast Florida region. Detections from individuals recorded within the core winter habitat for > 20 d (n = 56) were incorporated into generalized linear mixedeffects models to investigate the influence of water temperature, photoperiod, moon phase, month and year on presence. The findings of this study suggest a temperature driven 'migrationresidency' model for mature lemon shark distribution across the USA eastern seaboard. Lemon sharks are distributed across a wide geographical area in the summer months and migrate south concentrating off southeast Florida in the winter, with this pattern repeated each year. From comparative genetic analysis and the absence of any evidence of mating behaviour during the winter residency period, mating and parturition most probably occur in May/June between northern Florida and the Carolinas. This study highlights the importance of determining the specific dynamics and proximate causes of animal movement and distribution over appropriate spatial and temporal scales relative to life history.

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