Life Sciences Commons^™

Lidar-Derived Benthic Habitat Maps Enable The Quantification Of Potential Dredging Impacts To Coral Reef Ecosystems, Brian K. Walker, Richard E. Dodge, David S. Gilliam

Marine & Environmental Sciences Faculty Proceedings, Presentations, Speeches, Lectures

An essential component to the analysis of ecosystem services is to characterize and define the major habitats within the area of interest. Aerial photography and/or satellite imagery coupled with geographic information systems (GIS) are frequently used to identify and quantify habitats in open terrestrial ecosystems. However, it is more difficult to successfully apply this methodology to deeper, <20 m, underwater environments. Light detection and ranging (LIDAR), a relatively new remote sensing technology that provides detailed bathymetry, can be used when adequate imagery is not available. This study uses LIDAR as the basis to characterize various benthic habitats in a coral reef ecosystem in order to quantify the habitats for a Habitat Equivalency Analysis (HEA) related to planned dredging activities to expand the Port Everglades entrance channel, Broward County, FL. As part of a regional mapping effort, marine benthic habitats were characterized for Broward County, FL. A mosaic of interpolated, sunshaded, laser bathymetry data served as the foundation upon which acoustic ground discrimination, limited subbottom profiling and aerial photography, and groundtruthing data were added in a GIS to aid in interpretation of benthic habitats. Expert-driven visual interpretation outlined geomorphological features in the LIDAR data at a scale of 1:6000 with a minimum mapping unit of 1 acre. The map of Broward County yielded a high overall accuracy of 89.6%. To quantify the potential dredging impacts, the habitat layer was clipped in GIS to the boundaries of anticipated direct and indirect impacts of the proposed project. Then the area of each clipped polygon was totaled for each habitat by impact type. HEA and Florida’s Uniform Mitigation Assessment Method (UMAM) were performed using these areas. This work would not have been possible using satellite imagery or aerial photography alone and illustrates the capability of relatively new remote sensing technologies to aid in the definition and quantification of habitats for ecosystem service analyses.

Coral Reef Restoration And Mitigation In Florida And Beyond, Jocelyn Karazsia, Tom Moore, James Byrne, David S. Gilliam, John Hunt

Marine & Environmental Sciences Faculty Proceedings, Presentations, Speeches, Lectures

No abstract provided.

Deep-Pelagic Fishes And The Mid-Atlantic Ridge: Interactions And Vectoring Of Gelatinous Carbon To Higher Trophic Levels?, Tracey Sutton, F. M. Porteiro, C. I. H. Anderson, J. Horne

Marine & Environmental Sciences Faculty Proceedings, Presentations, Speeches, Lectures

The assemblage structure and vertical distribution of deep-pelagic fishes relative to a mid-ocean ridge system is described from an acoustic and discrete-depth trawling survey conducted as part of the international Census of Marine Life field project MAR-ECO. A survey along the Mid-Atlantic Ridge (MAR), covering the full depth range (0 to >3000 m) with a combination of gear types, was conducted to understand the role of the pelagic fauna in ecosystem dynamics. A total of 205 fish species were collected by midwater sampling. Depth was by far the primary assemblage composition determinant, with ridge section secondary. The dominant ichthyofaunal component …

A Model Framework For Predicting Reef Fish Distributions Across The Seascape Using Gis Topographic Metrics And Benthic Habitat Associations, Brian K. Walker

Marine & Environmental Sciences Faculty Proceedings, Presentations, Speeches, Lectures

Increased topographic complexity has been linked to increased species diversity and/or abundance in many ecological communities, including coral reefs. Several topographic metrics can be measured remotely in GIS using high resolution bathymetry, including elevation, surface rugosity, and seafloor volume within specified areas. Statistical relationships between these data and organismal distributions within mapped habitats can be used to make predictions across the entire bathymetric dataset. In this study a model framework is presented which utilizes statistically significant relationships between reef fish abundance and species richness and GIS topographic complexity measurements for samples within similar benthic habitats to create GIS-based prediction maps …

Recovery Of Injured Giant Barrel Sponges, Xestospongia Muta, Offshore Southeast Florida, David S. Gilliam, Brian K. Walker, S. J. Saelens, Daniel P. Fahy, Vladimir N. Kosmynin

Marine & Environmental Sciences Faculty Proceedings, Presentations, Speeches, Lectures

Giant barrel sponges, Xestospongia muta, are abundant and important components of the southeast Florida reef system, and are frequently injured from anthropogenic and natural disturbances. There is limited information on the capacity of X. muta to recover from injury and on methods to reattach X. muta fragments. In late 2002, hundreds of barrel sponges offshore southeast Florida (Broward County) were accidentally injured during an authorized dredging operation. In early 2003, two to three months post-injury, 93% of 656 assessed injured sponges appeared to be recovering. In 2006, three years post-injury, nearly 90% of 114 monitored sponges continued to show …

Genetic Connectivity In The Branching Vase Sponge (Callyspongia Vaginalis) Across The Florida Reef Tract And Caribbean, Melissa B. Debiasse, Vincent P. Richards, Mahmood S. Shivji

Marine & Environmental Sciences Faculty Proceedings, Presentations, Speeches, Lectures

The Porifera constitute a substantial fraction of the biomass on coral reefs and frequently have higher species diversity than corals and algae, making this phylum an important model for the investigation of reef connectivity. We examined genetic connectivity in the common branching vase sponge, Callyspongia vaginalis, by analyzing DNA sequence variation in 511 bp of the mitochondrial cytochrome oxidase I (COI) gene in 401 individuals sampled from 16 locations throughout the Florida reef tract and Caribbean. Populations of Callyspongia vaginalis were highly genetically structured over the study area (ΦST = 0.48, P < 0.0001), including over distances as short as tens of kilometers within the Florida reef tract, and had a significant overall pattern of isolation by distance (P = 0.0002). However, nonsignificant pairwise ΦST values were also found between a few Florida sampling sites suggesting that long distance dispersal, perhaps by means of fragmentation, may occur over continuous, shallow coastlines. Indeed, sufficient gene flow appears to occur along the Florida reef tract to obscure a signal of isolation by distance (P = 0.164), but not to homogenize haplotype frequencies over 465 km from Palm Beach to the Dry Tortugas. Statistical parsimony analysis revealed two highly divergent haplotypes from Honduras suggestive of cryptic speciation. Inferences from a nested clade analysis supported the pattern of restricted gene flow and isolation by distance in the Caribbean, and suggested a northward range extension of C. vaginalis from a hypothesized Central American …

Contrasting Patterns Of Population Structure And Dispersal For The Giant Barrel Sponge (Xestospongia Muta) Within The Florida Reef Tract And Caribbean, Vincent P. Richards, Kevin A. Feldheim, Mahmood S. Shivji

Marine & Environmental Sciences Faculty Proceedings, Presentations, Speeches, Lectures

Sponges are one of the dominant fauna on Florida and Caribbean reefs, with species diversity often exceeding that of scleractinian corals. Despite their importance as structural components and habitat providers on reefs, their dispersal dynamics are little understood. We utilized eight microsatellite markers to study the population structure and migration patterns of the giant barrel sponge (Xestospongia muta), a widespread species throughout Florida and the Caribbean. Bayesian multilocus genotype analyses clustered 157 samples from the Bahamas, Honduras, and the US Virgin Islands into three distinct groups. 159 samples from nine locations within 284 km of the Florida reef …

Coral Ultrastructural Response To Elevated Pco2 And Nutrients During Tissue Repair And Regeneration, Dorothy-Ellen A. Renegar, Patricia Blackwelder, Alison L. Moulding

Marine & Environmental Sciences Faculty Proceedings, Presentations, Speeches, Lectures

Corals and coral reefs have recently experienced widespread decline attributed to anthropogenic pressure on reef systems. Studies have demonstrated that nutrient and pCO₂ stress effect coral growth and calcification, but study of specific effects on coral tissue is lacking. The objective of this research was to examine wound healing in corals and how it is affected by exposure to elevated nutrients and pCO₂. Coral tissue repair and regeneration during wound healing in Montastraea cavernosa and Porites astreoides were assessed histologically and ultrastructurally by examining colony fragments exposed to elevated nitrate, phosphate, and pCO₂. In M. …

Ultrastructural And Histological Analysis Of Dark Spot Syndrome In Siderastrea Siderea And Agaricia Agaricites, Dorothy-Ellen A. Renegar, Patricia Blackwelder, J. D. Miller, D. J. Gochfeld, Alison L. Moulding

Marine & Environmental Sciences Faculty Proceedings, Presentations, Speeches, Lectures

Dark Spot Syndrome (DSS) typically manifests in scleractinian corals as lesions of varying color, size, shape and location that can result in skeletal changes and tissue death. A causative agent for DSS has not yet been identified. The objective of this study was histological and ultrastructural comparison of the cellular and skeletal characteristics of DSS-affected and healthy Siderastrea siderea and Agaricia agaricites. The greater resolution possible with transmission electron microscopy (TEM) revealed microbial activity and tissue changes not resolvable utilizing histology. DSS-affected tissue had less integrity, with increasing cellular degradation and vacuolization. A high concentration of electron dense inclusions, …

Population Status Of Acropora Corals In The Florida Keys, Steven Miller, Mark Chiappone, Leanne M. Rutten, Dione W. Swanson

Marine & Environmental Sciences Faculty Proceedings, Presentations, Speeches, Lectures

Population declines of staghorn coral (Acropora cervicornis) and elkhorn coral (A. palmata) are often-cited examples of Caribbean reef change since the 1970s, due, in part, to disease and localized effects from storms and predation. Both corals were listed as threatened on the U.S. Endangered Species List based upon range-wide decline and poor recovery. A spatially intensive survey undertaken in the Florida Keys of Acropora corals quantified habitat distribution, colony abundance, size, and condition at 235 sites spanning over 200 km in 2007. A two-stage stratified sampling design using belt transects incorporated cross-shelf habitats and no-fishing management …

Stony Coral Species Diversity And Cover In The Florida Keys Using Design-Based Sampling, Leanne M. Rutten, Mark Chiappone, Dione W. Swanson, Steven Miller

Marine & Environmental Sciences Faculty Proceedings, Presentations, Speeches, Lectures

Large-scale sampling of stony coral species richness, species distribution, and cover was undertaken at 423 Florida Keys sites between Miami and SW of Key West during 2005 and 2007. A two-stage, stratified random sampling design employed belt transects to enumerate numbers of species and point-intercept surveys to quantify cover. The sampling design incorporated ten reef and hard-bottom habitats from < 1 m to 27 m depth, as well as oceanographic regions and areas inside and outside of protected management zones. These data provide insights into the spatial extent and factors influencing stony coral biodiversity. For stony corals, a pool of ~50 taxa encompassing the Orders Milleporina and Scleractinia, including species and morphotypes, was recorded. Significant differences were found in species richness and cover among cross-shelf habitats, with great values on inner shelf margin patch reefs, followed by deeper fore-reef slope habitats that extended to the 27 m depth limit sampled. In contrast, the shallow fore-reef, especially in areas historically dominated by the branching coral Acropora palmata, yielded relatively low numbers of species and cover that are presently dominated by smaller, brooding corals such as Porites astreoides and Favia fragum.

Population Structure In The Brown Tube Sponge (Agelas Conifera) In The Florida Reef Tract And Caribbean, Jennifer M. Hester, Vincent P. Richards, Kevin Feldheim, Mahmood S. Shivji

Marine & Environmental Sciences Faculty Proceedings, Presentations, Speeches, Lectures

Sponges are broadly distributed, occur in a wide range of habitats, and comprise a substantial amount of the biomass and macro-biodiversity on coral reefs. Despite their ubiquity in reef ecosystems, their dispersal dynamics are largely unknown. Here we report on gene flow and population structure for the common brown tube sponge, Agelas conifera (Demospongiae, Poecilosclerida) in the Florida reef tract and Caribbean. Over 300 samples collected from ten geographically distinct locations throughout Florida and the Caribbean are being analyzed for variation at eight microsatellite loci. Preliminary results from screening four loci in 295 individuals from eight locations indicated significant population …

Population Genetic Structure Of A Coral Reef Ecosystem Apex Predator, The Gray Reef Shark (Carcharhinus Amblyrhynchos), Rebekah L. Horn, William Robbins, Douglas Mccauley, Philip Lobel, Mahmood S. Shivji

Marine & Environmental Sciences Faculty Proceedings, Presentations, Speeches, Lectures

Sharks play a major functional role as apex predators in coral reef ecosystems, raising concerns that their ongoing overexploitation will compromise the integrity and sustainability of reefs. The gray reef shark (Carcharhinus amblyrhynchos) is a strongly coral reef associated species whose populations are known to have declined substantially in some regions. There is no information on population structure in this species to aid in their management and conservation. We are assessing genetic structure in this species by using entire mitochondrial control region sequences and 15 nuclear microsatellite loci as markers. 93 gray reef shark samples were obtained from …

Interpreting The Spatial Distribution Of Bathypelagic Nekton Along The Mid-Atlantic Ridge, C. I. H. Anderson, J. Horne, Tracey Sutton

Marine & Environmental Sciences Faculty Proceedings, Presentations, Speeches, Lectures

The spatial distribution of organisms plays a key role in facilitating biological processes, such as trophic interactions, which govern ecosystem structure and function. Attempts to understand bathypelagic (1000-4000 m depth) ecosystem dynamics have been hampered by the coarse temporal-spatial resolution and static nature of most sampling strategies. This study combines a traditional approach, based on discrete net trawls sampling small volumes, with the continuous full water column coverage provided by fisheries acoustics to investigate the distribution of biomass along the Mid-Atlantic Ridge (MAR). The limited trawl samples have been interpreted as showing a positive relationship between the presence of the …

Mercury Transport And Bioaccumulation In The Alvarado Lagoon System, Veracruz State, Mexico, Edward O. Keith, Jane L. Guentzel

Marine & Environmental Sciences Faculty Proceedings, Presentations, Speeches, Lectures

The Alvarado Lagoon System (ALS) consists of shallow rivers and lagoons connected to the Gulf of Mexico (GOMEX) by a narrow channel. We collected samples of water and seafood in the wet (September 2005) and dry (March 2003 and 2005) seasons, and human hair and sediment in 2005. Total Hg in sediments ranged from 27.5 to 90.5 μg Hg/g dry weight, while fish and shellfish Hg levels ranged from 0.01 to 0.35 μg Hg/g wet weight. Total Hg in human hair ranged from 0.10 to 3.36 μg Hg/g (n = 47) and 58 % of the hair samples were above …

Bathypelagic Fish Diversity In The Sargasso Sea, Northwestern Atlantic Ocean, Tracey Sutton, Peter Wiebe, Ann Bucklin, Laurence P. Madin

Marine & Environmental Sciences Faculty Proceedings, Presentations, Speeches, Lectures

Of the various marine habitats, one of the (if not the) most daunting to quantify is the under-sampled bathypelagic zone (> 1000 m depth), which at 60% of the ocean’s volume is the largest habitat on Earth. One project addressing this challenge is the Census of

Marine Zooplankton (CMarZ), whose goal is the assessment of biodiversity of animal plankton throughout the world’s oceans. The 2006 CMarZ cruise in the Western North Atlantic provided an unprecedented opportunity to sample bathypelagic micronekton using a large midwater trawl (10-m2 MOCNESS) outfitted with fine (0.335-mm) mesh netting. This netting allowed non-destructive sampling of the …

Who's Eating Whom? Identification And Quantification Of Deep-Pelagic Prey Fishes In The North Atlantic Ocean, A. Heger, Tracey Sutton

Marine & Environmental Sciences Faculty Proceedings, Presentations, Speeches, Lectures

Understanding the structure and functioning of marine ecosystems requires accurate knowledge of trophic interactions. Trophic ecology studies generally underestimate prey diversity due to the difficulties imposed by digestion. Further, this degradation leads to uncertainty in the quantification of prey biomass (i.e., energy flow between various ecosystem components). Trophic interactions in the deep sea are poorly known relative to coastal ecosystems due to an incomplete inventory of meso-and bathypelagic species composition. The CoML field project MAR-ECO has increased our knowledge of the faunal structure of the mid-North Atlantic. Deep-pelagic fish specimens from the 2004 MARECO expedition provided a basis for an …

The Importance Of Stealth: Recent Findings With The Eye-In-The-Sea Deep-Sea Observatory, Edith A. Widder, E. H. Raymond, Tracey Sutton

Marine & Environmental Sciences Faculty Proceedings, Presentations, Speeches, Lectures

The Eye-in-the-Sea (EITS) observatory was designed to be acoustically quiet and to use far-red illumination to observe deep-sea animals unobtrusively. The EITS has clearly demonstrated the critical importance of stealth in research ocean observatories. Its use has revealed both animals and behaviors never seen before. Additionally recordings of animal activity under different lighting conditions and in the presence or absence of different sound-producing vehicles (ROVs and submersibles) have revealed to what extent tools for exploration bias observations. Recent recordings made during a 2007 NOAA Ocean Exploration mission to deep waters around the Bahamas provide excellent additional examples of the importance …

Real-Time Coral Stress Observations Before, During, And After Beach Nourishment Dredging Offshore Se Florida, L. Fisher, Kenneth Banks, David S. Gilliam, Richard E. Dodge, D. Stout, Bernardo Vargas-Ángel, Brian K. Walker

Marine & Environmental Sciences Faculty Proceedings, Presentations, Speeches, Lectures

Beach nourishment in Southeast Florida involves dredging sand source borrow areas located between offshore reefs. From May 2005 to February 2006 Broward County, FL. nourished 10.9 km of beach with 1.5 ×106 m3 of sand. As part of a program to monitor potential reef community impacts, a visual stress index was developed from laboratory experiments and histological analyses for three stony coral species (Montastrea cavernosa, Solenastrea bournoni, and Siderastrea siderea). Scoring involved healthy = 0; moderately stressed = 1 (polyp swelling, increased mucus); markedly stressed = 2 (coloration changes, increased mucus secretion, tissue thinning); and severely stressed = 3 (severe …

Patterns In Southeast Florida Coral Reef Community Composition, M. P. Sathe, David S. Gilliam, Richard E. Dodge, L. E. Fisher

Marine & Environmental Sciences Faculty Proceedings, Presentations, Speeches, Lectures

The Southeast (SE) Florida coral reef system is the northern extension of the Florida reef tract. This high latitude system lies offshore a heavily populated and urbanized coast and therefore is affected by numerous environmental and anthropogenic stressors. Using annual monitoring data collected in 2004, the southeast lorida reef community was analyzed to investigate patterns in community composition in various habitat types. Data was collected by SCUBA divers who conducted a 30m2 belt transect survey at 24 sample sites offshore Broward County (SE), Florida. Sites ranged in depth range from six to 18 meters. The 24 sites occurred on five …

Long-Term Monitoring Of A High-Latitude Coral Reef System Off Southeast Florida, Usa: A Partnership Between Academia And Resource Management, David S. Gilliam, Kenneth Banks, Michael Callahan, Chantal Collier, Richard E. Dodge, Louis E. Fisher, Jennifer Wheaton

Marine & Environmental Sciences Faculty Proceedings, Presentations, Speeches, Lectures

Significant coral reef community development exists along the eastern shelf of the United States from the Dry Tortugas through the Florida Keys (Monroe County) and Southeast (SE) Florida (Miami-Dade, Broward, Palm Beach, and Martin Counties). State and county resource managers have partnered with academia to monitor the health of the SE Florida reef system. Since 2000, more than 20 sites have been monitored annually offshore Broward County. Quantitative data includes stony coral species cover, colony size, density, and condition (bleaching, disease, etc.) and gorgonian and sponge density. The SE Florida Coral Reef Evaluation and Monitoring Project (SECREMP) was established in …