Life Sciences Commons^™

Development Of Highly Sensitive Environmental Dna Methods For The Detection Of Bull Sharks, Carcharhinus Leucas (Müller And Henle, 1839), Using Droplet DigitalTm Pcr, Katherine E. Schweiss, Ryan N. Lehman, J. Marcus Drymon, Nicole M. Phillips

Faculty Publications

Background: As apex and mesopredators, elasmobranchs play a crucial role in maintaining ecosystem function and balance in marine systems. Elasmobranch populations worldwide are in decline as a result of exploitation via direct and indirect fisheries mortalities and habitat degradation; however, a lack of information on distribution, abundance, and population biology for most species hinders their effective management. Environmental DNA analysis has emerged as a cost‐effective and non‐invasive technique to fill some of these data gaps, but often requires the development of species‐specific methodologies.

Aims: Here, we established eDNA methodology appropriate for targeted species detections of Bull Sharks, Carcharhinus …

In Situ Observations Of Fish Larvae Encased Within A Pelagic Gelatinous Matrix, Adam T. Greer, Luciano M. Chiaverano, James G. Ditty, Frank J. Hernandez

Faculty Publications

The degree to which marine fish larvae aggregate (i.e. patchiness) is predominantly determined by the physical oceanographic environment. Biological traits, however, can also influence spatial distributions and have adaptive value for larvae (e.g. favorable transport or reducing predation mortality). Although several fish families are known to release eggs within a gelatinous matrix, hatched larvae have not been found inside this type of structure. We present observations of hatched, preflexion yolk-sac larvae encased within a pelagic gelatinous matrix (mass). Two different masses (40-60 mm in length) containing free swimming, elongate larvae were imaged in the northern Gulf of Mexico (nGOM) near …

Laboratory Growth Of Denitrifying Water Column Microbia Consortia From Deep-Sea Shipwrecks In The Northern Gulf Of Mexico, Dhanya Haridas, Justin C. Biffinger, Thomas J. Boyd, Preston A. Fulmer, Leila J. Hamdan, Lisa A. Fitzgerald

Faculty Publications

Background: Shipwrecks serve as a rich source for novel microbial populations that have largely remained undiscovered. Low temperatures, lack of sunlight, and the availability of substrates derived from the shipwreck’s hull and cargo may provide an environment in which microbes can develop unique metabolic adaptations.

Methods: To test our hypothesis that shipwrecks could influence the microbial population involved in denitrification when a consortium is grown in the laboratory, we collected samples proximate to two steel shipwrecks in the northern Gulf of Mexico. Then under laboratory conditions, we grew two independent denitrifying microbial consortia. Each consortium was grown by …

Descriptive Density Models Of Scyphozoan Jellyfish In The Northern Gulf Of Mexico, Katrina T. Aleksa, Redwood W. Nero, Jerry D. Wiggert, William M. Graham

Faculty Publications

Jellyfish play an important role in the food web of many coastal environments but are generally considered a nuisance to scientific fieldwork and industrial and economic trades. A better understanding of how jellyfish densities and distributions are affected by environmental parameters could elucidate population trends and provide assistance in ecological research and undesirable human interactions. In this study, abundance data for scyphozoan medusae, Chrysaora sp. and Aurelia spp., were extracted from Southeast Area Monitoring and Assessment Program trawling surveys for the northern Gulf of Mexico (nGoM) during the summer and fall months. Both in situ and satellite oceanographic measurements were …

Temporal Migration Patterns Between Natal Locations Of Ruby-Throated Hummingbirds (Archilochus Colubris) And Their Gulf Coast Stopover Site, Theodore J. Zenzal Jr., Andrea J. Contina, Jeffrey F. Kelly, Frank R. Moore

Faculty Publications

Background

Autumn latitudinal migrations generally exhibit one of two different temporal migration patterns: type 1 where southern populations migrate south before northern populations, or type 2 where northern populations overtake southern populations en route. The ruby-throated hummingbird (Archilochus colubris) is a species with an expansive breeding range, which allows opportunities to examine variation in the timing of migration. Our objective was to determine a relationship between natal origin of ruby-throated hummingbirds and arrival at a Gulf coast stopover site; and if so, what factors, such as differences in body size across the range as well as the …

Condition Of Larval Spanish Mackerel Scomberomorus Maculatus In Relation To The Deepwater Horizon Oil Spill, John Timothy Ransom, J.E. Filbrun, Frank J. Hernandez Jr.

Faculty Publications

The Deepwater Horizon oil spill (DWHOS) coincided with the pelagic larval stages of many valued commercial and recreational fishes in the northern Gulf of Mexico. Larval fish survival and eventual recruitment into adult populations may have been impacted directly through toxicity or indirectly through changes in the planktonic food web caused by the release of oil and chemical dispersants during the DWHOS event. Using samples from a long-term ichthyoplankton survey off the coast of Alabama, USA, in a region impacted by the DWHOS, the abundance and condition of larval Spanish mackerel Scomberomorus maculatus were compared during summer months in years …

Condition Of Larval Red Snapper (Lutjanus Campechanus) Relative To Environmental Variability And The Deepwater Horizon Oil Spill, Frank J. Hernandez Jr., J.E. Filbrun, J. Fang, John Timothy Ransom

Faculty Publications

The Deepwater Horizon oil spill(DWHOS)spatially and temporally overlapped with the spawning of many fish species, including Red Snapper, one of the most economically important reef fish in the Gulf of Mexico. To investigate potential impacts of the DWHOS on larval Red Snapper, data from a long-term ichthyoplankton survey off the coast of Alabama were used to examine: (1)larval abundances among pre-impact (2007–2009), impact(2010), and post-impact (2011, 2013) periods; (2) proxies for larval condition (size-adjusted morphometric relationships and dry weight) among the same periods; and (3) the effects of background environmental variation on larval condition. We found that larval Red Snapper …

Land Cover Data For The Mississippi-Alabama Barrier Islands, 2010-2011 Arcgis V10.3 Geodatabase, Gregory A. Carter, Carlton P. Anderson, Kelly L. Lucas, Nathan L. Hopper

Land Cover Data for the Mississippi-Alabama Barrier Islands, 2010-2011

Land cover on the Mississippi-Alabama barrier islands was surveyed in 2010-2011 as part of continuing research on island geomorphic and vegetation dynamics following the 2005 impact of Hurricane Katrina. Results of the survey include sub-meter GPS location, a listing of dominant vegetation species and field photographs recorded at 375 sampling locations distributed among Cat, West Ship, East Ship, Horn, Sand, Petit Bois and West Dauphin Islands. The survey was conducted in a period of intensive remote sensing data acquisition over the northern Gulf of Mexico by federal, state and commercial organizations in response to the 2010 Macondo Well (Deepwater Horizon) …

Local Versus Generalized Phenotypes In Two Sympatric Aurelia Species: Understanding Jellyfish Ecology Using Genetics And Morphometrics, Luciano M. Chiaverano, Keith Bayha, William M. Graham

Faculty Publications

For individuals living in environmentally heterogeneous environments, a key component for adaptation and persistence is the extent of phenotypic differentiation in response to local environmental conditions. In order to determine the extent of environmentally induced morphological variation in a natural population distributed along environmental gradients, it is necessary to account for potential genetic differences contributing to morphological differentiation. In this study, we set out to quantify geographic morphological variation in the moon jellyfish Aurelia exposed at the extremes of a latitudinal environmental gradient in the Gulf of Mexico (GoM). We used morphological data based on 28 characters, and genetic data …

Regional Patterns In The Otolith Chemistry Of Juvenile Spotted Seatrout (Cynoscion Nebulosus) Differ Under Contrasting Hydrological Regimes, Chet F. Rakocinski, Bruce H. Comyns, Mark S. Peterson, Alan M. Shiller

Faculty Publications

The value of using otolith chemistry to characterize recruitment in terms of natal source regions depends on how consistently spatio-temporal variation can be resolved. The objective of this study was to compare regional classification patterns in the otolith chemistry of juvenile Spotted Seatrout (Cynoscion nebulosus) between two years experiencing disparate hydrological regimes, and separated by a five year interlude. Spatial patterns in the whole-otolith chemistry of juveniles of this estuarine-dependent species were compared between years using five otolith elements and two stable isotopes. Consistent size-related trends in uptake and deposition were evidenced by parallel ontogenetic relationships for six otolith variables. …

Nutrient Depletion As A Proxy For Microbial Growth In Deepwater Horizon Subsurface Oil/Gas Plumes, Alan M. Shiller, Dongjoo Joung

Faculty Publications

The Deepwater Horizon accident resulted in a substantial uncontrolled hydrocarbon release to the northern Gulf of Mexico, much of which was entrained in deep submerged plumes. While bio-degradation of the hydrocarbons has been inferred from microbial biomass and genetics, the amount of conversion of oil and gas carbon to biomass remains uncertain having only been estimated in modeling studies. Here we examine correlated depletions of nitrate, phosphate and oxygen in the submerged plumes and conclude that a substantial portion of hydrocarbons in these plumes was converted to biomass (0.8-2 x 10(10) mol C). This contrasts with nutrient-limited surface waters where …