Eastern Gulf Of Mexico Research Articles

New Poecilosclerida from mesophotic coral reefs and the deep-sea escarpment in the Pulley Ridge region, eastern Gulf of Mexico: Discorhabdella ruetzleri n.sp. (Crambeidae) and Hymedesmia (Hymedesmia) vaceleti n.sp. (Hymedesmiidae).

Pulley Ridge, a limestone ridge that extends nearly 300 km along the southwestern Florida shelf in the eastern Gulf of Mexico, supports a mesophotic coral ecosystem (59 to 94 m deep), surrounded by deeper waters. An ongoing evaluation of Porifera biodiversity observed and collected during expeditions by Harbor Branch Oceanographic Institute (2003-2015) have shown the existence of approximately 102 sponge species, with at least 20 species new to science. The present paper describes two novel Poecilosclerida from mesophotic reefs and deep escarpments in the Pulley Ridge Region, Eastern Gulf of Mexico, namely Discorhabdella ruetzleri n.sp. (Crambeidae, Poecilosclerida) and Hymedesmia (Hymedesmia) vaceleti n. sp. (Hymedesmiidae, Poecilosclerida). This is the first record of Discorhabdella for the greater Caribbean and the Central West Atlantic. The skeleton of D. ruetzleri n.sp. includes the unique pseudoastrose acanthostyles of the genus, and it is distinct from congeners in the size ranges of the megascleres and in the occurrence of predominantly smooth instead of tuberose choanosomal and ectosomal subtylostyles. The intense blue color and the spicule combination of Hymesdesmia (H.) vaceleti n.sp. makes this species unique among other Hymedesmia spp. from the western Atlantic. The discovery represents a considerable expansion in the known biogeographical distribution of the genus Discorhabdella which is represented now by six species with a discrete geographic distribution (New Zealand, Azores, Western Mediterranean Sea, Eastern Pacific in Panama). This work is the first contribution to an ongoing effort to discover and document the importance of sponge biodiversity on mesophotic reefs and associated deep-water habitats in the Gulf of Mexico and the Caribbean.

Evidence for intense biotic interactions in the eastern Gulf of Mexico after a two million year hiatus: inferences from muricid edge-drilling behaviour

Evidence for intense biotic interactions in the eastern Gulf of Mexico after a two million year hiatus: inferences from muricid edge-drilling behaviour

E&P Notes (May 2018)

E&P Notes ‘Enormous’ Merge Play Resource Rivals Major World Gas Fields, Largest Discoveries Joel Parshall, JPT Features Editor Producers in the recently opened Merge play of Oklahoma’s Anadarko Basin are sitting atop a resource that rivals some of the world’s major gas fields and largest new discoveries, Geology CEO Greg Augsburger of Citizen Energy told the SPE Gulf Coast Section Business Development Group recently. Merge lies between the prolific Sooner Trend, Anadarko, and Canadian and Kingfisher (counties) (STACK) and South Central Oklahoma Oil Province (SCOOP) plays, effectively tying them together. Privately funded Citizen Energy, formed in 2012, drilled the Merge discovery well in September 2015 and 18 delineation wells before significant competitor interest emerged. The discovery, made by the Governor James B. Edwards well in the Sycamore formation, was Citizen’s first company well. Concho Deal Creates Permian Basin Giant Matt Zborowski, Technology Writer Concho Resources has agreed to acquire RSP Permian in an all-stock deal valued at $9.5 billion including $1.5 billion in RSP debt. The move is expected to make Concho the Permian Basin’s most-active driller and its largest oil and gas producer from unconventional shale, the opera-tors said in a joint release. The combined company will hold some 640,000 net acres in the basin and operate a 27-rig program, with fourth-quarter 2017 production of 267,000 BOE/D. RSP is providing Concho some 92,000 net acres, split almost evenly between the Midland and Delaware Basins, along with seven active drilling rigs. Its fourth-quarter 2017 production was 56,000 BOE/D, of which 80% was oil and 20% was gas. Once the deal is complete, Concho will have 26,000 gross locations and net resources of 12.2 billion BOE. Latest Gulf of Mexico Lease Sale Generates Moderate Bidding Interest Stephen Whitfield, Senior Staff Writer The largest lease sale in the history of the US Gulf of Mexico (GOM) drew a lukewarm response from industry bidders, as a small percentage of available blocks received winning bids well below past price averages. Held in New Orleans on 21 March, Lease Sale 250 was the second offshore sale held under the National Outer Continental Shelf Oil and Gas Leasing Program (National OCS Program) for 2017–2022. Under this program, 10 regionwide lease sales are scheduled for the GOM, where oil and gas infrastructure is well established. Two lease sales will be held each year and include all available blocks in the combined Western, Central, and Eastern GOM planning areas. The lease sale included 14,474 unleased blocks. Excluded from the sale were blocks subject to the US congressional moratorium established by the Gulf of Mexico Energy Security Act of 2006; blocks that are adjacent or beyond the US Exclusive Economic Zone, in the area known as the northern portion of the Eastern Gap; and whole blocks and partial blocks within the current boundary of the Flower Garden Banks National Marine Sanctuary. Eni Enters Abu Dhabi Amid Zohr Efforts Offshore Egypt Matt Zborowski, Technology Writer Eni has notched agreements with a pair of Abu Dhabi companies that will increase the Italian multinational firm’s presence in the Middle East and give it another partner—along with cash—in its producing Zohr gas field offshore Egypt. Marking its entrance to Abu Dhabi, Eni has been awarded stakes in two off-shore fields for $875 million. It is receiving a 10% interest in the Umm Shaif and Nasr concession and a 5% interest in the Lower Zakum concession. The 40-year agreements are backdated to 9 March. Eni is paying a $575-million participation fee for the Umm Shaif and Nasr concession 135 km off Abu Dhabi, where oil production is targeted to reach 460,000 B/D. The Lower Zakum concession, 65 km off Abu Dhabi, comes with a $300-million participation fee and a production target of 450,000 B/D of oil. Oil was discovered at Lower Zakum in 1963, and production there began in 1967. Exploration Must Meet Tough Value Criteria Joel Parshall, JPT Features Editor Oil exploration has gone through a brutal period the last few years and remains commercially challenged, especially among companies that answer to a broad investor base. In a talk titled “The Exploration Conundrum,” before the Norwegian consulate general in Houston recently, Chief Upstream Strategist Bob Fryklund of IHS Markit said that pure exploration projects must meet tough value criteria to move ahead and companies must better communicate that value to the financial community. Yet communicating it stands as a tall order in today’s environment. Fryklund compared the 2014–2017 stock performances of four oil companies: An integrated supermajor A publicly traded national oil company with major international operations A United States onshore producer developing unconventional shale resources A pure international exploration company

Role of outer marginal collapse on salt deposition in the eastern Gulf of Mexico, Campos and Santos basins

Abstract Outer marginal collapse (OMC), a recently proposed process by which top-rift and base-salt unconformities formed near sea level may subside rapidly to 2.5–3 km at continental margins as mantle exhumation or seafloor spreading begins, needs further examination. We examine salt deposition at three margins and find that the differing positions and volumes of salt can be related to different durations of salt deposition as OMC and subsequent mantle exhumation proceed. Along NW Florida, salt is thin but deep and is interpreted as having formed at the start of OMC, before drowning further to abyssal depths. In the Campos Basin, salt is thick and extends across tens of kilometres of interpreted exhumed mantle, interpreted as having formed during the entire period of OMC before spreading onto mantle during exhumation. In the Santos Basin, salt is thick and extends across c. 100 km of interpreted exhumed mantle and/or oceanic crust, arguably requiring ‘lateral tectonic accommodation’, whereby salt deposition persists near global sea level across the conjugated salt basin during mantle exhumation beneath mobile salt. The supposition that OMC can account for salt deposition in three different basins without invoking problematic 1.5–2 km-deep subaerial depressions provides further support for the process.

Mercury in Cobia from Estuarine and Offshore Waters of the Southeastern United States: Fisheries Implications

AbstractIn marine ecosystems, upper‐trophic‐level pelagic fish often contain high concentrations of mercury. Individuals of several frequently landed marine fish species bioaccumulate mercury at concentrations linked directly to effects on fish physiology and human health risks. Knowledge of mercury in Cobias Rachycentron canadum has been limited. With this study, I addressed that problem by providing a comprehensive assessment of mercury in muscle taken from Cobia specimens within a range of size‐ and age‐classes representative of those targeted by the recreational and commercial fisheries operating in the southeastern United States (Atlantic Ocean and eastern Gulf of Mexico). Total mercury concentration (THg) in muscle ranged from 0.025 to 3.9 mg/kg (wet weight), with a mean of 0.743 mg/kg (SD = 0.609). In approximately 95% of all legal‐size Cobias (≥838.2 mm FL), THg exceeded 0.3 mg/kg (i.e., the U.S. Environmental Protection Agency's human health screening value for mercury). Proposed and recent increases in size limits for Cobias in some waters of the southeastern United States would further increase this percentage. The present results for Cobias from the western Atlantic and Gulf of Mexico further substantiate current fish consumption advisories and provide guidance for new or revised advisories in other regions.

Breeding sex ratio and population size of loggerhead turtles from Southwestern Florida.

Species that display temperature-dependent sex determination are at risk as a result of increasing global temperatures. For marine turtles, high incubation temperatures can skew sex ratios towards females. There are concerns that temperature increases may result in highly female-biased offspring sex ratios, which would drive a future sex ratio skew. Studying the sex ratios of adults in the ocean is logistically very difficult because individuals are widely distributed and males are inaccessible because they remain in the ocean. Breeding sex ratios (BSR) are sought as a functional alternative to study adult sex ratios. One way to examine BSR is to determine the number of males that contribute to nests. Our goal was to evaluate the BSR for loggerhead turtles (Caretta caretta) nesting along the eastern Gulf of Mexico in Florida, from 2013–2015, encompassing three nesting seasons. We genotyped 64 nesting females (approximately 28% of all turtles nesting at that time) and up to 20 hatchlings from their nests (n = 989) using 7 polymorphic microsatellite markers. We identified multiple paternal contributions in 70% of the nests analyzed and 126 individual males. The breeding sex ratio was approximately 1 female for every 2.5 males. We did not find repeat males in any of our nests. The sex ratio and lack of repeating males was surprising because of female-biased primary sex ratios. We hypothesize that females mate offshore of their nesting beaches as well as en route. We recommend further comparisons of subsequent nesting events and of other beaches as it is imperative to establish baseline breeding sex ratios to understand how growing populations behave before extreme environmental effects are evident.

Genetic population structure of the spotted seatrout (Cynoscion nebulosus): simultaneous examination of the mtDNA control region and microsatellite marker results

The spotted seatrout, Cynoscion nebulosus (Cuvier, 1830), lives almost entirely within natal estuaries, and although many genetic studies identify fine-scale population structure, they do not provide a consensus as to the number of stocks, the stock boundaries, or their connectivity. Two perceived limitations of previous studies were addressed. To address a presumption of limited sampling, we assembled a large sample size with broad geographic range: 547 specimens from 18 sampling areas (mean inter-area distance = 270 km) between Texas and North Carolina, representing the majority of this species' range. To address the presumptive limitations of genetic markers, two genetic marker types were compared: a 335-base-pair segment of the mitochondrial DNA (mtDNA) control region and 38 microsatellite loci. MtDNA haplotype frequencies were different only between populations of the Gulf of Mexico (GoM) and the Atlantic Ocean, but not between the western GoM and the eastern GoM. In contrast, the microsatellite loci characterized the species' range-wide population structure as three geographically non-overlapping clusters. These clusters were defined by two genetic breaks: one at the Apalachicola River, on Florida's Gulf Coast, and another in the Atlantic Ocean between Miami and Palm Beach on Florida's east coast. Moreover, within each genetic cluster (identified by microsatellite markers), a pattern of isolation by distance was evident. This new characterization of spotted seatrout population structure supports assessment and management of the species by individual states and defines distinct stock boundaries in Florida, the only state with multiple genetic stocks, as defined by either genetic marker type.

A new species of Lysmata Risso, 1816 (Crustacea, Decapoda, Lysmatidae) from the Gulf of Mexico.

A new species of peppermint shrimp, Lysmata baueri n. sp., is described based on a single specimen from the eastern Gulf of Mexico. The new species can be distinguished from other morphologically similar species of Lysmata Risso, 1816 by the number of teeth, length and shape of the rostrum, the length of the antennular peduncle relative to the scaphocerite, the number of meral and ischial articles in the second pereiopods, and the number of spines on the flexor margin of the dactyli from the third to fifth pereiopods. Morphological characters demonstrate that L. baueri n. sp., is most closely related to the eastern Pacific L. californica (Stimpson, 1866), L. nayaritensis Wicksten, 2000 and L. porteri (Rathbun, 1907).

E&P Notes (November 2017)

E&P Notes Permian Winning Streak Could Be Running Out Stephen Rassenfoss, JPT Emerging Technology Senior Editor Hot shale plays tend to fall short of expectations after a few years, and the Permian Basin will be the next big test of the pattern. A recent technical paper by Robert Clarke, research director for Lower 48 Upstream for Wood Mackenzie, questions whether future drilling in the Permian will hit 5 million B/D in 2025 as the consultancy has predicted. Based on what he has been learning recently, some of it reported in SPE technical papers, the actual results could be worse or better, depending on how well the industry solves the problems that will come with intensive development in the Permian. Startup Aims To Advance Rocket Fuel Technology for Fracturing Stephen Whitfield, Senior Staff Writer A startup company in Canada is developing a tool that may help operators realize savings in resources and manpower in their fracturing operations. The PSI-CLONE tool from RocketFrac Services uses a proprietary solid rocket fuel mixture as a propellant fracturing mechanism which eliminates the need for significant water volumes. When loaded into the tool, deployed down a well, and ignited, the propellant releases high-pressure gas and creates enough pressure to produce fractures at targeted sites along the wellbore. The PSI-CLONE tool, which holds the propellant, is reusable. Once the propellant has burned out completely, the tool can be reloaded with another block of fuel. The company states that the system requires a single coiled tubing unit, as opposed to the multiple pumper trucks and water tanks used for hydraulic fracturing, and requires three to five onsite personnel Total Signs Deal With Chevron for Gulf of Mexico Acreage Supermajor Total increased its footprint in the US Gulf of Mexico, capturing seven prospects operated by Chevron. The agreement covers 16 blocks. Total, which recently increased its stake in the US Gulf of Mexico with its takeover of Maersk Oil, will participate in the seven wells through sharing between 25–40% interest. The prospects cover two promising plays: the Wilcox in the central Gulf of Mexico, next to the Anchor discovery; and the Norphlet, in the eastern Gulf of Mexico, near the Appomattox discovery. The first well already spudded in late July on the Ballymore prospect in the Mississippi Canyon. Energy Panel: Efficiency Focus Still Necessary in an Era of Transition Stephen Whitfield, Senior Staff Writer The oil price downturn has changed the way the oil and gas industry does business, and a panel of analysts and industry executives said that reinvention and creativity will be essential to surviving in a new reality. Held at the Global Energy Transitions Summit on the Rice University campus, the panel discussion featured an extensive look at how companies have managed to stay afloat in the current economic landscape. In September, oil prices reached their highest levels since April, but while industry hopes to see that figure sustain above $50/bbl and possibly reach $60, the panelists cautioned against getting overly enthusiastic. Greg Hill, president and COO of Hess, said “lower for longer” was still the primary factor behind his company’s operational strategy, and that it is not advantageous to build a business plan based on the possibility of future oil price growth.

The Camera-Based Assessment Survey System (C-BASS): A towed camera platform for reef fish abundance surveys and benthic habitat characterization in the Gulf of Mexico

An ongoing challenge for fisheries management is to provide cost-effective and timely estimates of habitat stratified fish densities. Traditional approaches use modified commercial fishing gear (such as trawls and baited hooks) that have biases in species selectivity and may also be inappropriate for deployment in some habitat types. Underwater visual and optical approaches offer the promise of more precise and less biased assessments of relative fish abundance, as well as direct estimates of absolute fish abundance. A number of video-based approaches have been developed and the technology for data acquisition, calibration, and synthesis has been developing rapidly.Beginning in 2012, our group of engineers and researchers at the University of South Florida has been working towards the goal of completing large scale, video-based surveys in the eastern Gulf of Mexico. This paper discusses design considerations and development of a towed camera system for collection of video-based data on commercially and recreationally important reef fishes and benthic habitat on the West Florida Shelf. Factors considered during development included potential habitat types to be assessed, sea-floor bathymetry, vessel support requirements, personnel requirements, and cost-effectiveness of system components. This regional-specific effort has resulted in a towed platform called the Camera-Based Assessment Survey System, or C-BASS, which has proven capable of surveying tens of kilometers of video transects per day and has the ability to cost-effective population estimates of reef fishes and coincident benthic habitat classification.

Minimizing bycatch and improving efficiency in the commercial bottom longline fishery in the Eastern Gulf of Mexico

We investigated the effects of hook soak time on targeted reef species and shark bycatch in the reef fish bottom longline fishery in the Gulf of Mexico. Beginning in 2010, capture time and catch per unit effort (CPUE) for the primary target species red grouper (Epinephelus morio) in the fishery were evaluated using hook timers. Findings indicated that typical duration of hook soak times is longer than necessary to efficiently harvest red grouper and a reduction in gear soak times to less than one hour would result in minimal or no reduction in red grouper CPUE. The mean capture time of sharks and red grouper differed significantly, suggesting that a reduction in soak time would likely reduce the bycatch of sharks in the fishery. The study also revealed barometric pressure, lunar phase, and fish size were significant covariates with red grouper capture times and that different bait types significantly affected CPUE. Implementing shorter hook soak times would likely improve fishery profitability and potentially reduce discards of unwanted species in the fishery.

Sediment source regions and paleotransport of the Upper Jurassic Norphlet Formation, eastern Gulf of Mexico

The Upper Jurassic Norphlet Formation is an eolian sandstone and important hydrocarbon reservoir that overlies the Louann Salt in the Gulf of Mexico (GOM). Because the sand was concentrated into dunes formed by Late Jurassic winds, determining the source areas and paleotransport direction of the sand can improve predictions of the distribution of the dune facies around the GOM. Paleo–wind-blown sediment transport into the proto-GOM was controlled by wind direction and magnitude and the extant topography of the basin and adjacent uplands. Analysis of the Norphlet Formation in the eastern GOM shows that wadis and alluvial fans controlled by the location of highs were the primary route for introducing sediment of varied provenance into the eolian erg. Eolian transport directions interpreted from dip-log analyses are south directed in southern Alabama and west to northwest directed in western Florida. Interpretations of regional, two-dimensional, prestack-depth-migrated seismic data show that erosional incision of the Middle Ground arch occurred prior to and during the time of Norphlet deposition; this as well as preexisting lows in the basement topography may have facilitated basinward sand transport of sediment that fed the Norphlet Formation erg preserved in the deep-water subsurface eastern GOM.

Reprint of – Deep-sea coral and hardbottom habitats on the west Florida slope, eastern Gulf of Mexico

Until recently, benthic habitats dominated by deep-sea corals (DSC) appeared to be less extensive on the slope of the Gulf of Mexico (GOM) than in the northeast Atlantic Ocean or off the southeastern US. There are relatively few bioherms (i.e., coral-built mounds) in the northern GOM, and most DSCs are attached to existing hard substrata (e.g., authigenically formed carbonate). The primary structure-forming, DSC in the GOM is Lophelia pertusa, but structure is also provided by other living and dead scleractinians, antipatharians (black corals), octocorals (gorgonians, soft corals), hydrocorals and sponges, as well as abundant rocky substrata. The best development of DSCs in the GOM was previously documented within Viosca Knoll oil and gas lease blocks 826 and 862/906 (north-central GOM) and on the Campeche Bank (southern GOM in Mexican waters). This paper documents extensive deep reef ecosystems composed of DSC and rocky hard-bottom recently surveyed on the West Florida Slope (WFS, eastern GOM) during six research cruises (2008–2012). Using multibeam sonar, CTD casts, and video from underwater vehicles, we describe the physical and oceanographic characteristics of these deep reefs and provide size or area estimates of deep coral and hardground habitats. The multibeam sonar analyses revealed hundreds of mounds and ridges, some of which were subsequently surveyed using underwater vehicles. Mounds and ridges in <525m depths were usually capped with living coral colonies, dominated by L. pertusa. An extensive rocky scarp, running roughly north-south for at least 229km, supported lower abundances of scleractinian corals than the mounds and ridges, despite an abundance of settlement substrata. Areal comparisons suggested that the WFS may exceed other parts of the GOM slope in extent of living deep coral coverage and other deep-reef habitat (dead coral and rock). The complex WFS region warrants additional studies to better understand the influences of oceanography and geology on the occurrence of DSC and associated organisms. Protection measures are being considered to ensure the long-term integrity of this diverse ecosystem.

Lightning whelk natural history and a new sourcing method

ABSTRACTArtifacts made from sinistral (left-handed) whelk shells are commonly found at inland archaeological sites in eastern North America. Past attempts to source the coast of origin of these marine shells based on chemical analyses have provided tentative results. A knowledge of sinistral whelk natural history is essential before attempting shell sourcing studies. The common occurrence of sinistral whelks in the Gulf of Mexico and their uncommon occurrence along both the South Atlantic and Mid-Atlantic bights are documented. Critical biogeographical and morphological information is presented, as well as a new method of sourcing artifacts based on spire-angle measurements. Sinistral whelk artifacts from Spiro, East St. Louis, and Cahokia probably came from the eastern Gulf of Mexico.

An Ecosystem‐Based Approach to Evaluating Impacts and Management of Invasive Lionfish

Species invasions in marine ecosystems pose a threat to native fish communities and can disrupt the food webs that support valuable commercial and recreational fisheries. In the Gulf of Mexico, densities of invasive Indo‐Pacific Lionfish, Pterois volitans and P. miles, are among the highest in their invaded range. In a workshop setting held over a 2‐week period, we adapted an existing trophic dynamic model of the West Florida Shelf, located in the eastern Gulf of Mexico, to simulate the lionfish (both species) invasion and community effects over a range of harvest scenarios for both lionfish and native predators. Our results suggest small increases in lionfish harvest can reduce peak biomass by up to 25% and also that reduced harvest of native reef fish predators can lead to lower lionfish densities. This model can help managers identify target harvest and benefits of a lionfish fishery and inform the assessment and management of valuable reef fish fisheries.

The effects of base-salt relief on salt flow and suprasalt deformation patterns — Part 2: Application to the eastern Gulf of Mexico

In the eastern Gulf of Mexico, the pattern of early stage salt flow is complicated by basement topography consisting of a series of plunging arches that trend obliquely to the early flow direction. Seismic lines downdip of the Florida Middle Ground Arch reveal a puzzling array of structures. Sections trending roughly north–south (parallel to the regional dip) document predominantly extensional structures; however, east–west sections reveal shortening structures. Both sets of structures occur well updip of the downdip salt pinchout. We designed a physical-modeling study to investigate these puzzling relationships. Models presented in Part 1 of this paper indicate that localized shortening and extension can occur as salt passes over simple base-salt steps. Physical models were run with complex salt isopachs featuring plunging arches oblique to dip and salt flow. Models reveal the formation of shortening belts as the salt and its thin prekinematic overburden are translated across the arches. The complex salt isopachs deflect salt flow to produce convergent and divergent flow, which, along with flow-velocity gradients, results in the rotation of early formed thrust belts. Rotations of up to 70° were recorded in the most complex model, resulting in transported fold belts with trends that were close to dip parallel, similar to those observed on seismic data from the eastern Gulf of Mexico. Additional zones of shortening are found in and around complex salt pinchouts in the updip zones of the gravity-gliding system. The dynamic nature of these salt-related tectonic systems can result in the downdip translation of fold belts far from the basement topography over which they were created.

Modified MODIS fluorescence line height data product to improve image interpretation for red tide monitoring in the eastern Gulf of Mexico

Several satellite-based methods have been used to detect and trace Karenia brevis red tide blooms in the eastern Gulf of Mexico. Some require data statistics and multiple data products while others use a single data product. Of these, the MODIS normalized fluorescence line height (nFLH) has shown its advantage of detecting blooms in waters rich in colored dissolved organic matter, thus having been used routinely to assess bloom conditions by the Florida Fish and Wildlife Conservation Commission (FWC), the official state agency of Florida responsible for red tide monitoring and mitigation. However, elevated sediment concentrations in the water column due to wind storms can also result in high nFLH values, leading to false-positive bloom interpretation. Here, a modified nFLH data product is developed to minimize such impacts through empirical adjustments of the nFLH values using MODIS-derived remote sensing reflectance in the green band at 547 nm. The new product is termed as an algal bloom index (ABI), which has shown improved performance over the original nFLH in both retrospective evaluation statistics and near real-time applications. The ABI product has been made available in near real-time through a Web portal and has been used by the FWC on a routine basis to guide field sampling efforts and prepare for red tide bulletins distributed to many user groups.

Deep-sea coral and hardbottom habitats on the west Florida slope, eastern Gulf of Mexico

Until recently, benthic habitats dominated by deep-sea corals (DSC) appeared to be less extensive on the slope of the Gulf of Mexico (GOM) than in the northeast Atlantic Ocean or off the southeastern US. There are relatively few bioherms (i.e., coral-built mounds) in the northern GOM, and most DSCs are attached to existing hard substrata (e.g., authigenically formed carbonate). The primary structure-forming, DSC in the GOM is Lophelia pertusa, but structure is also provided by other living and dead scleractinians, antipatharians (black corals), octocorals (gorgonians, soft corals), hydrocorals and sponges, as well as abundant rocky substrata. The best development of DSCs in the GOM was previously documented within Viosca Knoll oil and gas lease blocks 826 and 862/906 (north-central GOM) and on the Campeche Bank (southern GOM in Mexican waters). This paper documents extensive deep reef ecosystems composed of DSC and rocky hard-bottom recently surveyed on the West Florida Slope (WFS, eastern GOM) during six research cruises (2008–2012). Using multibeam sonar, CTD casts, and video from underwater vehicles, we describe the physical and oceanographic characteristics of these deep reefs and provide size or area estimates of deep coral and hardground habitats. The multibeam sonar analyses revealed hundreds of mounds and ridges, some of which were subsequently surveyed using underwater vehicles. Mounds and ridges in <525m depths were usually capped with living coral colonies, dominated by L. pertusa. An extensive rocky scarp, running roughly north-south for at least 229km, supported lower abundances of scleractinian corals than the mounds and ridges, despite an abundance of settlement substrata. Areal comparisons suggested that the WFS may exceed other parts of the GOM slope in extent of living deep coral coverage and other deep-reef habitat (dead coral and rock). The complex WFS region warrants additional studies to better understand the influences of oceanography and geology on the occurrence of DSC and associated organisms. Protection measures are being considered to ensure the long-term integrity of this diverse ecosystem.

Mexican origins for the Texas green turtle foraging aggregation: A cautionary tale of incomplete baselines and poor marker resolution

The green turtle (Chelonia mydas) foraging aggregation along the Texas coast has increased dramatically in recent years, but the source populations for these turtles have not been adequately resolved. Previous mixed stock analysis (MSA) based on 490 base pair (bp) mitochondrial control region haplotypes suggested a large Florida contribution, but widespread sharing of common haplotypes among potential source populations and incomplete source population baseline data precluded precise assessment. To test the hypothesis that Texas turtles may represent proximal western Gulf of Mexico (GoM) nesting populations, we analyzed novel rookery samples from Rancho Nuevo, Tamaulipas, Mexico (RNMX) and conducted oceanic connectivity simulations. The RNMX samples yielded haplotypes CM-A1.1 and CM-A3.1 in frequencies not significantly different from those of the central eastern Florida nesting population. However, mitogenomic sequencing identified a diagnostic mitochondrial SNP (mtSNP) variant that is fixed in RNMX relative to the Florida CM-A1.1 lineage. Pairwise comparisons indicate that the Tamaulipas rookery represents a discrete population relative to those previously described in the northern Greater Caribbean, warranting recognition of a western GoM management unit (MU). Contrary to previous findings, the Florida populations were ruled out as major contributors to the Texas aggregation through screening of the mtSNP. Mixed stock analysis incorporating the mtSNP data suggested a western GoM origin for approximately 70% of the Texas foraging aggregation, with Quintana Roo contributing the majority of the remainder. Backtracking simulations within an ocean circulation model were broadly congruent with genetic results in indicating substantial probability of oceanic transport from Mexican rookeries to the Texas coast (68%) while also dismissing the possibility of transport from the eastern Florida rookeries (0%). The mixed stock analyses and backtracking simulations are consistent with previous hypotheses implicating oceanic dispersal followed by natal homing by neritic juveniles to explain juvenile green turtle distributions. In contrast to a pattern of stepping stone connectivity across the remaining northern Greater Caribbean, the Texas foraging aggregation was distinct from all others analyzed in the region, including one in the eastern GoM. This isolation highlights the significance of Texas as developmental habitat for the proposed western GoM MU and reiterates the importance of continued international cooperation to facilitate recovery of this stock. This study also underscores the importance of satisfying underlying assumptions of mixed stock analysis in order to make robust inferences of connectivity.

A new species of symbiotic palaemonid shrimp of the genus Pseudocoutierea Holthuis, 1951 (Decapoda: Caridea: Palaemonidae) from the eastern Gulf of Mexico, with an updated key for the identification of species of the genus.

A new species of symbiotic palaemonid shrimp of the genus Pseudocoutierea Holthuis, 1951, is described based on a specimen collected in the eastern Gulf of Mexico, off the southwest coast of Florida. Pseudocoutierea stephanieae sp. nov., is the seventh known in this genus, and morphologically most similar to P. antillensis Chace, 1972, and P. conchae Criales, 1981, from the western Atlantic, and P. elegans Holthuis, 1952, from the eastern Pacific, all sharing an expanded rostral base or eaves that terminate supra-distally in an acute tooth. This new species can be separated by: the presence of an epigastric knob or tubercle on the anterior mid-dorsal third of the carapace, which is absent in all other congeneric species; the shape of the pterygostomial sinus, which is shallow in this new species, whereas it is deep and well defined in all other congeneric species. An updated dichotomous key to species of Pseudocoutierea is presented.