Climate drives coupled regime shifts across subtropical estuarine ecosystems.

Ecological regime shifts are expected to increase this century as climate change propagates cascading effects across ecosystems with coupled elements. Here, we demonstrate that the climate-driven salt marsh-to-mangrove transition does not occur in isolation but is linked to lesser-known oyster reef-to-mangrove regime shifts through the provision of mangrove propagules. Using aerial imagery spanning 82 y, we found that 83% of oyster reefs without any initial mangrove cover fully converted to mangrove islands and that mean (± SD) time to conversion was 29.

Natural recovery of a marine foundation species emerges decades after landscape-scale mortality.

Globally, the conditions and time scales underlying coastal ecosystem recovery following disturbance remain poorly understood, and post-disturbance examples of resilience based on long-term studies are particularly rare. Here, we documented the recovery of a marine foundation species (turtlegrass) following a hypersalinity-associated die-off in Florida Bay, USA, one of the most spatially extensive mortality events for seagrass ecosystems on record. Based upon annual sampling over two decades, foundation species recovery across the landscape was demonstrated by two ecosystem responses: the range of turtlegrass biomass met or exceeded levels present prior to the die-off, and turtlegrass regained dominance of seagrass community structure.

Long-term performance of seagrass restoration projects in Florida, USA.

Seagrass restoration is a common tool for ecosystem service enhancement and compensatory mitigation for habitat loss. However, little is known about the long-term performance of these projects. We identified seagrass restoration projects by reviewing historic permitting documents, monitoring reports, and studies conducted in Florida, USA, most of which have not been cited previously in peer-reviewed literature.

Three-dimensional interstitial space mediates predator foraging success in different spatial arrangements.

Identifying and quantifying the relevant properties of habitat structure that mediate predator-prey interactions remains a persistent challenge. Most previous studies investigate effects of structural density on trophic interactions and typically quantify refuge quality using one or two-dimensional metrics. Few consider spatial arrangement of components (i.

Predator Diet and Trophic Position Modified with Altered Habitat Morphology.

Empirical patterns that emerge from an examination of food webs over gradients of environmental variation can help to predict the implications of anthropogenic disturbance on ecosystems. This "dynamic food web approach" is rarely applied at the coastal margin where aquatic and terrestrial systems are coupled and human development activities are often concentrated. We propose a simple model of ghost crab (Ocypode quadrata) feeding that predicts changing dominant prey (Emerita talpoida, Talorchestia sp.

Saltmarsh boundary modulates dispersal of mangrove propagules: implications for mangrove migration with sea-level rise.

Few studies have empirically examined the suite of mechanisms that underlie the distributional shifts displayed by organisms in response to changing climatic condition. Mangrove forests are expected to move inland as sea-level rises, encroaching on saltmarsh plants inhabiting higher elevations. Mangrove propagules are transported by tidal waters and propagule dispersal is likely modified upon encountering the mangrove-saltmarsh ecotone, the implications of which are poorly known.

Tidal events and salt-marsh structure influence black mangrove (Avicennia germinans) recruitment across an ecotone.

Field experiments were conducted at a black mangrove-salt-marsh ecotone in southwest Florida (U.S.A.

Risk of predation reflects variation in the reproductive strategy of a dominant forage fish in mangrove tidal tributaries.

The role of predators in shaping prey life histories is a central theme in the ecological literature. However, the association between degree of predation risk and prey reproductive strategies has not been clearly established. We examined reproduction in the sailfin molly (Poecilia latipinna) from small tidal tributaries in a subtropical estuary.

Foraging behavior under starvation conditions is altered via photosynthesis by the marine gastropod, Elysia clarki.

It has been well documented that nutritional state can influence the foraging behavior of animals. However, photosynthetic animals, those capable of both heterotrophy and symbiotic photosynthesis, may have a delayed behavioral response due to their ability to photosynthesize. To test this hypothesis we subjected groups of the kleptoplastic sea slug, Elysia clarki, to a gradient of starvation treatments of 4, 8, and 12 weeks plus a satiated control.

Colonization of a dynamic substrate: factors influencing recruitment of the wood-boring isopod, Sphaeroma terebrans, onto red mangrove (Rhizophora mangle) prop roots.

The isopod Sphaeroma terebrans, which bores into the prop roots of the red mangrove, Rhizophora mangle, can cause death and subsequent breakage of the inhabited root and, debatably, may reduce the support system of the tree. We examined whether different characteristics of a root or its physical setting, both of which may relate to habitat quality, influence the colonization of S. terebrans.

Toward a landscape approach in seagrass beds: using macroalgal accumulation to address questions of scale.

An experimental investigation of drift macroalgal accumulation in seagrass beds was conducted to determine if the relationship between passively dispersed plant structure and the spatial arrangement of rooted macrophytes differed when examined across two spatial scales. Experiments were performed from December 1992 to April 1993 at four different sites in Tampa Bay, Florida, utilizing artificial seagrass units (ASUs) of uniform shoot length and density but with different areal dimensions [1 m (S) versus 4 m (L)]. Drift macroalgae were also collected from 1 m×1 m plots of natural seagrass at each of the experimental sites from November 1990 to May 1992 to determine the relationship between macroalgal abundance and structural characteristics of natural seagrass.

Production in Natural and Restored Seagrasses: A Case Study of a Macrobenthic Polychaete.

Restoration of seagrass beds has been suggested as a method to correct declining vegetation cover in shallow waters. Secondary production of the polychaete Kinbergonuphis simoni was used to evaluate faunal equivalency of newly restored (2-yr-old) seagrass beds to beds that are mature (at least 17 yr old) in an embayment in Tampa Bay, Florida. Information on density of polychaetes, size structure, reproductive characteristics, and production (growth increment summation method) was collected from May 1989 to February 1991 from individuals within monthly sediment cores from both planted and natural seagrass beds.

Field evidence that shrimp predation regulates meiofauna.

The grass shrimp Palaemonetes pugio, a suspected predator/disturber on meiofauna, and other large natant forms (>2 mm) were selectively excluded from microecosystem tanks for nine months during which time replicability between the tanks was established. Subsequently, shrimp were reintroduced into one of the four tanks via an aquarium and the meiofauna populations monitored in the "shrimp" and control tanks. In the presence of the predator/disturber, total meiofauna, nematode, oligochaete, and polychaete densities were significantly lower than in control tanks.