Open Access. Powered by Scholars. Published by Universities.®

Marine Biology Commons™

Open Access. Powered by Scholars. Published by Universities.®

University of South Alabama

Discipline
Keyword
Publication Year
Publication
Publication Type

Articles 31 - 60 of 60

Full-Text Articles in Marine Biology

Tiger Sharks Eat Songbirds: Reply, J. Marcus Drymon, K. Feldheim, A. M.V. Fournier, A. E. Jefferson, A. M. Kroetz, Sean P. Powers, E. A. Seubert Jan 2019

Tiger Sharks Eat Songbirds: Reply, J. Marcus Drymon, K. Feldheim, A. M.V. Fournier, A. E. Jefferson, A. M. Kroetz, Sean P. Powers, E. A. Seubert

University Faculty and Staff Publications

In response to our recent paper (Drymon et al. 2019), Yosef (2019) questions the mechanism proposed to explain interactions between tiger sharks (Galeocerdo cuvier) and migratory songbirds, while offering an alternative mechanism based on a single observation. We appreciate the comments from Yosef and the opportunity to respond.

Go to article

Tiger Sharks Eat Songbirds: Scavenging A Windfall Of Nutrients From The Sky, J. Marcus Drymon, K. Feldheim, A. M.V. Fournier, E. A. Seubert, A. E. Jefferson, A. M. Kroetz, Sean P. Powers Jan 2019

Tiger Sharks Eat Songbirds: Scavenging A Windfall Of Nutrients From The Sky, J. Marcus Drymon, K. Feldheim, A. M.V. Fournier, E. A. Seubert, A. E. Jefferson, A. M. Kroetz, Sean P. Powers

University Faculty and Staff Publications

No abstract provided.

Go to article

Stable Isotopes Reveal Opportunistic Foraging In A Spatiotemporally Heterogeneous Environment: Bird Assemblages In Mangrove Forests, Christina Buelow, April Reside, Ronald Baker, Marcus Sheaves Nov 2018

Stable Isotopes Reveal Opportunistic Foraging In A Spatiotemporally Heterogeneous Environment: Bird Assemblages In Mangrove Forests, Christina Buelow, April Reside, Ronald Baker, Marcus Sheaves

University Faculty and Staff Publications

Environmental heterogeneity can foster opportunistic foraging by mobile species, resulting in generalized resource and habitat use. Determining species’ food web roles is important to fully understand how ecosystems function, and stable isotopes can provide insight into the foraging ecology of bird assemblages. We investigated flexibility of food choice in mangrove bird assemblages of northeast Australia by determining whether species’ carbon and nitrogen isotopic values corresponded to foraging group classification described in the literature, such as groups of species that are omnivorous or insectivorous. Subsequently, we evaluated foraging group isotopic niche size, overlap, degree of individual specialization, and the probable proportions …

Go to article

Short-Term Low Salinity Mitigates Effects Of Oil And Dispersant On Juvenile Eastern Oysters: A Laboratory Experiment With Implications For Oil Spill Response Activities, Meagan N. Schrandt, Sean Powers, F.Scott Rikard, Wilawan Thongda, Eric Peatman Sep 2018

Short-Term Low Salinity Mitigates Effects Of Oil And Dispersant On Juvenile Eastern Oysters: A Laboratory Experiment With Implications For Oil Spill Response Activities, Meagan N. Schrandt, Sean Powers, F.Scott Rikard, Wilawan Thongda, Eric Peatman

University Faculty and Staff Publications

Following the Deepwater Horizon oil spill, eastern oyster (Crassostrea virginica) reefs in the northern Gulf of Mexico were exposed to oil and various associated clean-up activities that may have compromised oyster reef health. Included in the exposure was oil, dispersant, and in some locales, atypical salinity regimes. Oil and dispersants can be detrimental to oysters and the effects of salinity depend on the level. In addition to these extrinsic factors, genetic diversity of oyster populations may help the oysters respond to stressors, as demonstrated in other systems. We used a 3×3×2 factorial design to experimentally examine the effects …

Go to article

Estimating Exploitation Rates In The Alabama Red Snapper Fishery Using A High-Reward Tag–Recapture Approach, Dana K. Sackett, Mattgew Catalano, J. Marcus Drymon, Sean P. Powers, Mark Albins Jan 2018

Estimating Exploitation Rates In The Alabama Red Snapper Fishery Using A High-Reward Tag–Recapture Approach, Dana K. Sackett, Mattgew Catalano, J. Marcus Drymon, Sean P. Powers, Mark Albins

University Faculty and Staff Publications

Accurate estimates of exploitation are essential to managing an exploited fishery. However, these estimates are often dependent on the area and vulnerable sizes of fish considered in a study. High-reward tagging studies offer a simple and direct approach to estimating exploitation rates at these various scales and in examining how model parameters impact exploitation rate estimates. These methods can ultimately provide a better understanding of the spatial dynamics of exploitation at smaller local and regional scales within a fishery—a measure often needed for more site-attached species, such as the Red Snapper Lutjanus campechanus. We used this approach to tag 724 …

Go to article

Compression And Relaxation Of Fishing Effort In Response To Changes In Length Of Fishing Season For Red Snapper (Lutjanus Campechanus) In The Northern Gulf Of Mexico, Sean P. Powers, Kevin Anson Jan 2018

Compression And Relaxation Of Fishing Effort In Response To Changes In Length Of Fishing Season For Red Snapper (Lutjanus Campechanus) In The Northern Gulf Of Mexico, Sean P. Powers, Kevin Anson

University Faculty and Staff Publications

A standard method used by fisheries managers to decrease catch and effort is to shorten the length of a fishery; however, data on recreational angler response to this simple approach are surprisingly lacking. We assessed the effect of variable season length on daily fishing effort, measured by using numbers of boat launches per day, anglers per boat, and anglers per day from video observations, in the recreational sector of the federal fishery for red snapper (Lutjanus campechanus) in coastal Alabama. From 2012 through 2017, season length fluctuated from 3 to 40 d. Daily effort, measured by using mean number of …

Go to article

Red Snapper Distribution On Natural Habitats And Artificial Structures In The Northern Gulf Of Mexico, Mandy Karnauskas, John F. Walter Iii, Matthew D. Campbell, Adam G. Pollack, J. Marcus Drymon, Sean P. Powers Jan 2017

Red Snapper Distribution On Natural Habitats And Artificial Structures In The Northern Gulf Of Mexico, Mandy Karnauskas, John F. Walter Iii, Matthew D. Campbell, Adam G. Pollack, J. Marcus Drymon, Sean P. Powers

University Faculty and Staff Publications

In 2011, an intensive, multiple-gear, fishery-independent survey was carried out in the northern Gulf of Mexico (GOM) to collect comprehensive age and length information on Red Snapper Lutjanus campechanus. Based on this synoptic survey, we produced a spatial map of Red Snapper relative abundance that integrates both gear selectivity effects and ontogenetically varying habitat usage. Our methodology generated a spatial map of Red Snapper at a 10-km2 grid resolution that is consistent with existing knowledge of the species: Red Snapper occurred in relatively high abundances at depths of 50–90 m along the coasts of Texas and Louisiana and in smaller, …

Go to article

Effects Of Shoreline Dynamics On Saltmarsh Vegetation, Shailesh Sharma, Joshua Goff, Ryan M. Moody, Ashley Mcdonald, Dorothy Byron, Kenneth L. Heck Jr., Sean Powers, Carl Ferraro, Just Cebrian Jul 2016

Effects Of Shoreline Dynamics On Saltmarsh Vegetation, Shailesh Sharma, Joshua Goff, Ryan M. Moody, Ashley Mcdonald, Dorothy Byron, Kenneth L. Heck Jr., Sean Powers, Carl Ferraro, Just Cebrian

University Faculty and Staff Publications

We evaluated the impact of shoreline dynamics on fringing vegetation density at mid- and low-marsh elevations at a high-energy site in the northern Gulf of Mexico. Particularly, we selected eight unprotected shoreline stretches (75 m each) at a historically eroding site and measured their inter-annual lateral movement rate using the DSAS method for three consecutive years. We observed high inter-annual variability of shoreline movement within the selected stretches. Specifically, shorelines retrograded (eroded) in year 1 and year 3, whereas, in year 2, shorelines advanced seaward. Despite shoreline advancement in year 2, an overall net erosion was recorded during the survey …

Go to article

Marine Ecoregion And Deepwater Horizon Oil Spill Affect Recruitment And Population Structure Of A Salt Marsh Snail, Steven C. Pennings, Scott Zengel, Jacob Oehrig, Merryl Alber, T. Dale Bishop, Donald R. Deis, Donna Devlin, A. Randall Hughes, John J. Hutchens, Jr., Whitney M. Kiehn, Caroline R. Mcfarlin, Clay L. Montague, Sean P. Powers, C. Edward Proffitt, Nicholle Rutherford, Camille L. Stagg, Keith Walters Jan 2016

Marine Ecoregion And Deepwater Horizon Oil Spill Affect Recruitment And Population Structure Of A Salt Marsh Snail, Steven C. Pennings, Scott Zengel, Jacob Oehrig, Merryl Alber, T. Dale Bishop, Donald R. Deis, Donna Devlin, A. Randall Hughes, John J. Hutchens, Jr., Whitney M. Kiehn, Caroline R. Mcfarlin, Clay L. Montague, Sean P. Powers, C. Edward Proffitt, Nicholle Rutherford, Camille L. Stagg, Keith Walters

University Faculty and Staff Publications

Marine species with planktonic larvae often have high spatial and temporal variation in recruitment that leads to subsequent variation in the ecology of benthic adults. Using a combination of published and unpublished data, we compared the population structure of the salt marsh snail, Littoraria irrorata, between the South Atlantic Bight and the Gulf Coast of the United States to infer geographic differences in recruitment and to test the hypothesis that the Deepwater Horizon oil spill led to widespread recruitment failure of L. irrorata in Louisiana in 2010. Size-frequency distributions in both ecoregions were bimodal, with troughs in the distributions consistent …

Go to article

Development Of A Low-Cost Arduino-Based Sonde For Coastal Applications, Grant Lockridge, Brian Dzwonkowski, Reid Nelson, Sean P. Powers Jan 2016

Development Of A Low-Cost Arduino-Based Sonde For Coastal Applications, Grant Lockridge, Brian Dzwonkowski, Reid Nelson, Sean P. Powers

University Faculty and Staff Publications

This project addresses the need for an expansion in the monitoring of marine environments by providing a detailed description of a low cost, robust, user friendly sonde, built on Arduino Mega 2560 (Mega) and Arduino Uno (Uno) platforms. The sonde can be made without specialized tools or training and can be easily modified to meet individual application requirements. The platform allows for internal logging of multiple parameters of which conductivity, temperature, and GPS position are demonstrated. Two design configurations for different coastal hydrographic applications are highlighted to show the robust and versatile nature of this sensor platform. The initial sonde …

Go to article

Spatial And Dietary Overlap Creates Potential For Competition Between Red Snapper (Lutjanus Campechanus) And Vermilion Snapper (Rhomboplites Aurorubens), William T. Davis, J. Marcus Drymon, Sean P. Powers Dec 2015

Spatial And Dietary Overlap Creates Potential For Competition Between Red Snapper (Lutjanus Campechanus) And Vermilion Snapper (Rhomboplites Aurorubens), William T. Davis, J. Marcus Drymon, Sean P. Powers

University Faculty and Staff Publications

Understanding the complex nature of direct and indirect species interactions is a critical precursor to successful resource management. In the northern Gulf of Mexico fisheries ecosystem, red snapper (Lutjanus campechanus) and vermilion snapper (Rhomboplites aurorubens) are two commercially harvested species within a larger reef fish complex. These two species share similar habitats and diets; however, little is known about how these species partition habitat and dietary resources. In this study we examined the extent of spatial and dietary overlap between red snapper and vermilion snapper, and experimentally compared their feeding behavior. Field data from multiple gear …

Go to article

Facilitation And Dominance In A Schooling Predator: Foraging Behavior Of Florida Pompano, Trachinotus Carolinus, Meagan N. Schrandt, Sean P. Powers Jun 2015

Facilitation And Dominance In A Schooling Predator: Foraging Behavior Of Florida Pompano, Trachinotus Carolinus, Meagan N. Schrandt, Sean P. Powers

University Faculty and Staff Publications

Presumably an individual’s risk of predation is reduced by group membership and this ‘safety in numbers’ concept has been readily applied to investigations of schooling prey; however, foraging in groups may also be beneficial. We tested the hypothesis that, when feeding in groups, foraging of a coastal fish (Florida Pompano, Trachinotus carolinus) on a benthic prey source would be facilitated (i.e. fish feeding in groups will consume more prey items). Although this question has been addressed for other fish species, it has not been previously addressed for Florida Pompano, a fish known to exhibit schooling behavior and that is …

Go to article

Natural Shorelines Promote The Stability Of Fish Communities In An Urbanized Coastal System, Steven B. Scyphers, Tarik C. Gouhier, Jonathan H. Grabowski, Michael W. Beck, John Mareska, Sean P. Powers Jun 2015

Natural Shorelines Promote The Stability Of Fish Communities In An Urbanized Coastal System, Steven B. Scyphers, Tarik C. Gouhier, Jonathan H. Grabowski, Michael W. Beck, John Mareska, Sean P. Powers

University Faculty and Staff Publications

Habitat loss and fragmentation are leading causes of species extinctions in terrestrial, aquatic and marine systems. Along coastlines, natural habitats support high biodiversity and valuable ecosystem services but are often replaced with engineered structures for coastal protection or erosion control. We coupled high-resolution shoreline condition data with an eleven-year time series of fish community structure to examine how coastal protection structures impact community stability. Our analyses revealed that the most stable fish communities were nearest natural shorelines. Structurally complex engineered shorelines appeared to promote greater stability than simpler alternatives as communities nearest vertical walls, which are among the most prevalent …

Go to article

The Role Of Citizens In Detecting And Responding To A Rapid Marine Invasion, Steven B. Scyphers, Sean P. Powers, J. Lad Akins, J. Marcus Drymon, Charles W. Martin, Zeb H. Schobernd, Pamela J. Schofield, Robert L. Shipp, Theodore S. Switzer Jan 2015

The Role Of Citizens In Detecting And Responding To A Rapid Marine Invasion, Steven B. Scyphers, Sean P. Powers, J. Lad Akins, J. Marcus Drymon, Charles W. Martin, Zeb H. Schobernd, Pamela J. Schofield, Robert L. Shipp, Theodore S. Switzer

University Faculty and Staff Publications

Documenting and responding to species invasions requires innovative strategies that account for ecological and societal complexities. We used the recent expansion of Indo-Pacific lionfish (Pterois volitans/miles) throughout northern Gulf of Mexico coastal waters to evaluate the role of stakeholders in documenting and responding to a rapid marine invasion. We coupled an online survey of spearfishers and citizen science monitoring programs with traditional fishery-independent data sources and found that citizen observations documented lionfish 1–2 years earlier and more frequently than traditional reef fish monitoring programs. Citizen observations first documented lionfish in 2010 followed by rapid expansion and proliferation in …

Go to article

Distribution And Dynamic Habitat Use Of Young Bull Sharks Carcharhinus Leucas In A Highly Stratified Northern Gulf Of Mexico Estuary, J. Marcus Drymon, Matthew J. Ajemian, Sean P. Powers May 2014

Distribution And Dynamic Habitat Use Of Young Bull Sharks Carcharhinus Leucas In A Highly Stratified Northern Gulf Of Mexico Estuary, J. Marcus Drymon, Matthew J. Ajemian, Sean P. Powers

University Faculty and Staff Publications

Understanding how animals alter habitat use in response to changing abiotic conditions is important for effective conservation management. For bull sharks (Carcharhinus leucas), habitat use has been widely examined in the eastern and western Gulf of Mexico; however, knowledge of their movements and the factors influencing them is lacking for populations in the more temperate north-central Gulf of Mexico. To examine how changes in hydrographic conditions affected the presence of young bull sharks in Mobile Bay, Alabama, thirty-five sharks were fitted with internal acoustic transmitters and monitored with an acoustic monitoring array consisting of thirty-three receivers between June …

Go to article

Integrating Societal Perspectives And Values For Improved Stewardship Of A Coastal Ecosystem Engineer, Steven B. Scyphers, J. Steven Picou, Robert D. Brumbaugh, Sean P. Powers Jan 2014

Integrating Societal Perspectives And Values For Improved Stewardship Of A Coastal Ecosystem Engineer, Steven B. Scyphers, J. Steven Picou, Robert D. Brumbaugh, Sean P. Powers

University Faculty and Staff Publications

Oyster reefs provide coastal societies with a vast array of ecosystem services, but are also destructively harvested as an economically and culturally important fishery resource, exemplifying a complex social-ecological system (SES). Historically, societal demand for oysters has led to destructive and unsustainable levels of harvest, which coupled with multiple other stressors has placed oyster reefs among the most globally imperiled coastal habitats. However, more recent studies have demonstrated that large-scale restoration is possible and that healthy oyster populations can be sustained with effective governance and stewardship. However, both of these require significant societal support or financial investment. In our study, …

Go to article

Novel Pathways For Injury From Offshore Oil Spills: Direct, Sublethal And Indirect Effects Of The Deepwater Horizon Oil Spill On Pelagic Sargassum Communities, Sean P. Powers, Frank J. Hernandez, Jr, Robert H. Condon, J. Marcus Drymon, Christopher M. Free Sep 2013

Novel Pathways For Injury From Offshore Oil Spills: Direct, Sublethal And Indirect Effects Of The Deepwater Horizon Oil Spill On Pelagic Sargassum Communities, Sean P. Powers, Frank J. Hernandez, Jr, Robert H. Condon, J. Marcus Drymon, Christopher M. Free

University Faculty and Staff Publications

The pelagic brown alga Sargassum forms an oasis of biodiversity and productivity in an otherwise featureless ocean surface. The vast pool of oil resulting from the Deepwater Horizon oil spill came into contact with a large portion of the Gulf of Mexico’s floating Sargassum mats. Aerial surveys performed during and after the oil spill show compelling evidence of loss and subsequent recovery of Sargassum. Expanding on the trends observed in the aerial surveys, we conducted a series of mesocosm experiments to test the effect of oil and dispersants on the vertical position and weight of the Sargassum complex ( …

Go to article

Gulf-Wide Decreases In The Size Of Large Coastal Sharks Documented By Generations Of Fishermen, Sean P. Powers, F. Joel Frodrie, Steven B. Scyphers, J. Marcus Drymon, Robert L. Shipp, Gregory W. Stunz Jan 2013

Gulf-Wide Decreases In The Size Of Large Coastal Sharks Documented By Generations Of Fishermen, Sean P. Powers, F. Joel Frodrie, Steven B. Scyphers, J. Marcus Drymon, Robert L. Shipp, Gregory W. Stunz

University Faculty and Staff Publications

Large sharks are top predators in most coastal and marine ecosystems throughout the world, and evidence of their reduced prominence in marine ecosystems has been a serious concern for fisheries and ecosystem management. Unfortunately, quantitative data to document the extent, timing, and consequences of changes in shark populations are scarce, thwarting examination of long-term (decadal, century) trends, and reconstructions based on incomplete data sets have been the subject of debate. Absence of quantitative descriptors of past ecological conditions is a generic problem facing many fields of science but is particularly troublesome for fisheries scientists who must develop specific targets for …

Go to article

Multiscale Analysis Of Factors That Affect The Distribution Of Sharks Throughout The Northern Gulf Of Mexico, J. Marcus Drymon, Laure Carassou, Sean P. Powers, Mark Grace, John Dindo, Brian Dzwonkowski Jan 2013

Multiscale Analysis Of Factors That Affect The Distribution Of Sharks Throughout The Northern Gulf Of Mexico, J. Marcus Drymon, Laure Carassou, Sean P. Powers, Mark Grace, John Dindo, Brian Dzwonkowski

University Faculty and Staff Publications

Identification of the spatial scale at which marine communities are organized is critical to proper management, yet this is particularly difficult to determine for highly migratory species like sharks. We used shark catch data collected during 2006–09 from fishery- independent bottom-longline surveys, as well as biotic and abiotic explanatory data to identify the factors that affect the distribution of coastal sharks at 2 spatial scales in the northern Gulf of Mexico. Centered principal component analyses (PCAs) were used to visualize the patterns that characterize shark distributions at small (Alabama and Mississippi coast) and large (northern Gulf of Mexico) spatial scales. …

Go to article

Estimating The Potential Impacts Of Large Mesopredators On Benthic Resources: Integrative Assessment Of Spotted Eagle Ray Foraging Ecology In Bermuda, Matthew J. Ajemian, Sean P. Powers, Thaddeus J. T. Murdoch Jul 2012

Estimating The Potential Impacts Of Large Mesopredators On Benthic Resources: Integrative Assessment Of Spotted Eagle Ray Foraging Ecology In Bermuda, Matthew J. Ajemian, Sean P. Powers, Thaddeus J. T. Murdoch

University Faculty and Staff Publications

Declines of large sharks and subsequent release of elasmobranch mesopredators (smaller sharks and rays) may pose problems for marine fisheries management as some mesopredators consume exploitable shellfish species. The spotted eagle ray (Aetobatus narinari) is the most abundant inshore elasmobranch in subtropical Bermuda, but its predatory role remains unexamined despite suspected abundance increases and its hypothesized specialization for mollusks. We utilized a combination of acoustic telemetry, benthic invertebrate sampling, gut content analysis and manipulative experiments to assess the impact of spotted eagle rays on Bermudian shellfish resources. Residency and distribution of adult spotted eagle rays was monitored over …

Go to article

Age Composition And Distribution Of Red Drum (Sciaenops Ocellatus) In Offshore Waters Of The North Central Gulf Of Mexico: An Evaluation Of A Stock Under A Federal Harvest Moratorium, Sean P. Powers, Crystal Hightower, J. Marcus Drymon, Matthew W. Johnson Jan 2012

Age Composition And Distribution Of Red Drum (Sciaenops Ocellatus) In Offshore Waters Of The North Central Gulf Of Mexico: An Evaluation Of A Stock Under A Federal Harvest Moratorium, Sean P. Powers, Crystal Hightower, J. Marcus Drymon, Matthew W. Johnson

University Faculty and Staff Publications

Because of a lack of fishery- dependent data, assessment of the recovery of fish stocks that undergo the most aggressive form of management, namely harvest moratoriums, remains a challenge. Large schools of red drum (Sclaenops ocellatus) were common along the northern Gulf of Mexico until the late 1980s when increased fishing effort quickly depleted the stock. After 24 years of harvest moratorium on red drum in federal waters, the stock is in need of reassessment; however, fishery dependent data are not available in federal waters and fishery-independent data are limited. We document the distribution, age composition, growth, and condition of …

Go to article

Environmental Influences On Juvenile Fish Abundances In A River-Dominated Coastal System, Laure Carassou, Brian Dzwonkowski, Frank J. Hernandez, Jr., Sean P. Powers, William M. Graham, Kyeong Park, John Mareska Dec 2011

Environmental Influences On Juvenile Fish Abundances In A River-Dominated Coastal System, Laure Carassou, Brian Dzwonkowski, Frank J. Hernandez, Jr., Sean P. Powers, William M. Graham, Kyeong Park, John Mareska

University Faculty and Staff Publications

We investigated the influence of climatic and environmental factors on variations in juvenile abundances of marine fishes in a river-dominated coastal system of the north-central Gulf of Mexico, where an elevated primary productivity sustains fisheries of high economic importance. Fish were collected monthly with an otter trawl at three stations near Mobile Bay from 1982 to 2007. Fish sizes were used to isolate juvenile stages within the data set, and monthly patterns in juvenile fish abundance and size were then used to identify seasonal peaks for each species. The average numbers of juvenile fish collected during these seasonal peaks in …

Go to article

Oyster Reefs As Natural Breakwaters Mitigate Shoreline Loss And Facilitate Fisheries, Steven B. Scyphers, Sean P. Powers, Kenneth L. Heck Jr., Dorothy Byron Aug 2011

Oyster Reefs As Natural Breakwaters Mitigate Shoreline Loss And Facilitate Fisheries, Steven B. Scyphers, Sean P. Powers, Kenneth L. Heck Jr., Dorothy Byron

University Faculty and Staff Publications

Shorelines at the interface of marine, estuarine and terrestrial biomes are among the most degraded and threatened habitats in the coastal zone because of their sensitivity to sea level rise, storms and increased human utilization. Previous efforts to protect shorelines have largely involved constructing bulkheads and seawalls which can detrimentally affect nearshore habitats. Recently, efforts have shifted towards “living shoreline” approaches that include biogenic breakwater reefs. Our study experimentally tested the efficacy of breakwater reefs constructed of oyster shell for protecting eroding coastal shorelines and their effect on nearshore fish and shellfish communities. Along two different stretches of eroding shoreline, …

Go to article

An In Situ, Individual-Based Approach To Quantify Connectivity Of Marine Fish: Ontogenetic Movements And Residency Of Lingcod, Mary Anne Bishop, Brad F. Reynolds, Sean P. Powers Dec 2010

An In Situ, Individual-Based Approach To Quantify Connectivity Of Marine Fish: Ontogenetic Movements And Residency Of Lingcod, Mary Anne Bishop, Brad F. Reynolds, Sean P. Powers

University Faculty and Staff Publications

As modern fishery assessments change in an effort to be more accurate and encompass the range of potential ecosystem interactions, critical information on the ecology of species including life history, intra and inter-specific competitive interactions and habitat requirements must be added to the standard fishery-dependent and independent data sets. One species whose movements and habitat associations greatly affects exploitation patterns is lingcod, Ophiodon elongatus, which support an economically important fishery along the coastal waters of the Pacific Coast of North America. High site fidelity and limited movements within nearshore areas are hypothesized to have resulted in high catchability, a …

Go to article

Distributions Of Sharks Across A Continental Shelf In The Northern Gulf Of Mexico, J. Marcus Drymon, Sean P. Powers, John Dindo, Brian Dzwonkowski, Terry A. Henwood Dec 2010

Distributions Of Sharks Across A Continental Shelf In The Northern Gulf Of Mexico, J. Marcus Drymon, Sean P. Powers, John Dindo, Brian Dzwonkowski, Terry A. Henwood

University Faculty and Staff Publications

Declines in shark populations have sparked researchers and fishery managers to investigate more prudent approaches to the conservation of these fish. As managers strive to improve data collection for stock assessment, fisheries-independent surveys have expanded to include data-deficient areas such as coastal regions. To that end, a catch series from a nearshore survey off Alabama was combined with data from a concurrent offshore survey with identical methodology to examine the depth use of sharks across the continental shelf (2–366 m). The combined data set contained 22 species of sharks collected from 1995 to 2008: 21 species in the offshore data …

Go to article

Application Of Acoustic Telemetry To Assess Residency And Movements Of Rockfish And Lingcod At Created And Natural Habitats In Prince William Sound, Brad F. Reynolds, Sean P. Powers, Mary Anne Bishop Aug 2010

Application Of Acoustic Telemetry To Assess Residency And Movements Of Rockfish And Lingcod At Created And Natural Habitats In Prince William Sound, Brad F. Reynolds, Sean P. Powers, Mary Anne Bishop

University Faculty and Staff Publications

Loss and/or degradation of nearshore habitats have led to increased efforts to restore or enhance many of these habitats, particularly those that are deemed essential for marine fishes. Copper rockfish (Sebastes caurinus) and lingcod (Ophiodon enlongatus) are dominant members of the typical reef fish community that inhabit rocky and high-relief substrates along the Pacific Northwest. We used acoustic telemetry to document their residency and movements in the nearshore waters of Prince William Sound, Alaska in order to assess use of created reef habitat in an individual-based manner. A total of 57 fish were surgically implanted with …

Go to article

Seasonal Variability In Ichthyoplankton Abundance And Assemblage Composition In The Northern Gulf Of Mexico Off Alabama, Frank J. Hernandez, Jr, Sean P. Powers, William M. Graham Jan 2010

Seasonal Variability In Ichthyoplankton Abundance And Assemblage Composition In The Northern Gulf Of Mexico Off Alabama, Frank J. Hernandez, Jr, Sean P. Powers, William M. Graham

University Faculty and Staff Publications

Multiyear ichthyoplankton surveys used to monitor larval fish seasonality, abundance, and assemblage structure can provide early indicators of regional ecosystem changes. Numerous ichthyoplankton surveys have been conducted in the northern Gulf of Mexico, but few have had high levels of temporal resolution and sample replication. In this study, ichthyoplankton samples were collected monthly (October 2004–October 2006) at a single station off the coast of Alabama as part of a long-term biological survey. Four seasonal periods were identified from observed and historic water temperatures, including a relatively long (June–October) “summer” period (water temperature >26°C). Fish egg abundance, total larval abundance, and …

Go to article

Biology And Conservation Of Horseshoe Crabs, John T. Tanacredi, Mark L. Bottom, David R. Smith Jan 2009

Biology And Conservation Of Horseshoe Crabs, John T. Tanacredi, Mark L. Bottom, David R. Smith

School of Marine and Environmental Sciences Faculty and Staff Publications and Presentations

We dedicate this book to Drs. Carl N. Shuster, Jr. and Koichi Sekiguchi for their life-long contributions to the biology and conservation of the magnificent horseshoe crab.

Go to article

Unintended Facilitation Between Marine Consumers Generates Enhanced Mortality For Their Shared Prey, F. Joel Fodrie, Matthew D. Kenworthy, Sean P. Powers Dec 2008

Unintended Facilitation Between Marine Consumers Generates Enhanced Mortality For Their Shared Prey, F. Joel Fodrie, Matthew D. Kenworthy, Sean P. Powers

University Faculty and Staff Publications

We manipulated predator densities and prey vulnerability to explore how interactions between two predators affect overall mortality of their shared prey. Our threemember study system included eastern oysters (Crassostrea virginica) and two of its major consumers: southern oyster drills (Stramonita haemastoma) and stone crabs (Menippe adina). Field experiments demonstrated that drills and crabs foraging together generated higher than expected oyster mortality based on each species operating independently, even though crabs also killed some drills. In subsequent laboratory trials, we experimentally mimicked the handling of oysters by foraging crabs and confirmed that crabs facilitated drills by breeching oyster valves, thereby granting …

Go to article

Intertidal Benthic Resources Of The Copper River Delta, Alaska, Usa, Sean Powers, Mary Anne Bishop, Jonathan H. Grabowski, Charles H. Peterson Feb 2002

Intertidal Benthic Resources Of The Copper River Delta, Alaska, Usa, Sean Powers, Mary Anne Bishop, Jonathan H. Grabowski, Charles H. Peterson

University Faculty and Staff Publications

The Copper River Delta, Alaska is the largest contiguous coastal wetland system along the West Coast of North America. Vast expanses of tidal mud flats formed by sediments carried by the suspended load of the Copper River serve as a connection between the Gulf of Alaska and the extensive network of wetlands, rivers and sloughs of the delta system. In addition to providing habitat for resident fish, shrimp and crabs, these tidal flats serve as critical feeding grounds for up to 5 million migratory shorebirds as well as an entry and exit corridor for three species of commercially fished salmonids. …

Go to article

First Prev