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At least 379 records · Page 21Linked to original sources
USGS1983

Distribution and biology of Indo-Pacific insular hypogeal shrimps

Ten species of caridean shrimps, representing nine genera in five families, have been found in exposures of the marine water table at 28 islands from Hawaii to the western Indian Ocean. Synthesis of literature information and personal observations indicate that, as a group, these shrimps are characterized by red body pigment, reduced but pigmented eyes, euryhalinity, a proclivity for interstitial seawater in limestone or lava rock, generalized food requirements, and probable pre-Pleistocene origins. The shrimps have not been found in waters cooler than about 20°C. Species are often solitary, but as many as five are known to coexist. Six of the species have widely scattered populations, some as far apart as Hawaii and the Red Sea. Passive oceanic dispersal is endorsed as a general explanation for such apparently disjunct distributions. On the basis of an assumed primary habitat requirement of interstitial marine water, which could include that in shallow submerged rock as well as that in emergent (insular) rock, I hypothesize a much more cosmopolitan distribution of these shrimps in the Indo-Pacific Tropical Zone.

Bulletin of Marine Science↗
USGS1981

Environmental features and macrofauna of Kahana Estuary, Oahu, Hawaii

Lack of ecological information on Hawaiian estuaries prompted an intensive 2-year study of a small (5.7 ha) stream-mouth estuary on windward Oahu. Water quality and macrofauna were sampled weekly at seven stations. The water mass was strongly stratified vertically except during freshets. Average values for water column temperature and bottom salinity were 23.2°C and 12‰ at the head to 28.3°C and 28‰ at the mouth. Dissolved oxygen saturation in the water column varied from about 50% at night to 140% in the afternoon. Usually, bottom waters were 3–6°C warmer than surface waters and sometimes showed severe oxygen depletion. Macrofauna, collected primarily by seining, consisted mainly of decapod crustaceans (four species of crabs, seven species of shrimps) and fishes (24 species). Other typical estuarine taxons (mollusks, barnacles, polychaetes) were scarce or absent. Diversity increased seaward from 14 species near the estuary head to 29 species near the mouth. Three species of crustaceans and six of fishes were captured at all stations. Most abundant were the native prawn, Macrobrachium grandimanus , and mullet, Mugil cephalus . Perennially resident adults occurred among crustaceans and gobioid fishes; most other fishes were present as juveniles and sporadic adults. Comparisons with other data suggest that more than 50 species of native fishes may occur in Hawaiian estuaries, and that estuarine macrofaunal diversity on oceanic islands is much lower than on continents at similar latitudes.

Hawaii↗
USGS2004

Complex trophic interactions in kelp forest ecosystems

The distributions and abundances of species and populations change almost continuously. Understanding the processes responsible is perhaps ecology’s most fundamental challenge. Kelp-forest ecosystems in southwest Alaska have undergone several phase shifts between alga- and herbivore-dominated states in recent decades. Overhunting and recovery of sea otters caused the earlier shifts. Studies focusing on these changes demonstrate the importance of top-down forcing processes, a variety of indirect food-web interactions associated with the otter-urchin-kelp trophic cascade, and the role of food-chain length in the coevolution of defense and resistance in plants and their herbivores. This system unexpectedly shifted back to an herbivore-dominated state during the 1990s, because of a sea-otter population collapse that apparently was driven by increased predation by killer whales. Reasons for this change remain uncertain but seem to be linked to the whole-sale collapse of marine mammals in the North Pacific Ocean and southern Bering Sea. We hypothesize that killer whales sequentially "fished down" pinniped and sea-otter populations after their earlier prey, the great whales, were decimated by commercial whaling. The dynamics of kelp forests in southwest Alaska thus appears to have been influenced by an ecological chain reaction that encompassed numerous species and large scales of space and time.

Bulletin of Marine Science↗
USGS2000

Protection of fish spawning habitat for the conservation of warm temperate reef fish fisheries of shelf-edge reefs of Florida

We mapped and briefly describe the surficial geology of selected examples of shelf-edge reefs (50–120 m deep) of the southeastern United States, which are apparently derived from ancient Pleistocene shorelines and are intermittently distributed throughout the region. These reefs are ecologically significant because they support a diverse array of fish and invertebrate species, and they are the only aggregation spawning sites of gag ( Mycteroperca microlepis ), scamp ( M. phenax ), and other economically important reef fish. Our studies on the east Florida shelf in the Experimental Oculina Research Reserve show that extensive damage to the habitat-structuring coral Oculina varicosa has occurred in the past, apparently from trawling and dredging activities of the 1970s and later. On damaged or destroyed Oculina habitat, reef-fish abundance and diversity are low, whereas on intact habitat, reef-fish diversity is relatively high compared to historical diversity on the same site. The abundance and biomass of the economically important reef fish was much higher in the past than it is now, and spawning aggregations of gag and scamp have been lost or greatly reduced in size. On the west Florida shelf, fishers have concentrated on shelf-edge habitats for over 100 yrs, but fishing intensity increased dramatically in the 1980s. Those reefs are characterized by low abundance of economically important species. The degree and extent of habitat damage there is unknown. We recommend marine fishery reserves to protect habitat and for use in experimentally examining the potential production of unfished communities.

Florida↗
USGS1991

Impact of exploratory wells, offshore Florida: A biological assessment

Seven offshore exploratory oil well sites were examined in an effort to determine the ecological impact of exploratory drilling on the subtropical marine ecosystems of southern Florida, including seagrass beds and coral reefs. The time since drilling ranged from 2 to 29 years; water depths varied between 5 and 70 m. The major long-term ecological impact observed at these sites ranged from the creation of "artificial-reef" conditions to the physical destruction of hardbottom habitat that had not recovered in 29 years. Long-term ecological perturbation appeared to be limited to physical destruction and the deposition of drilling debris, which provided substratum for settling organisms. Significant deposits of drill muds or cuttings were not encountered at any of the sites, and there was no evidence of ecological damage from cuttings or drill muds. The results of this study pertain only to exploratory drilling that, unlike production wells that remain in place for tens of years, is a one-time perturbation to the habitat.

Florida↗
USGS1996

Biomass patterns in seagrass meadows of the Laguna Madre, Texas

The Laguna Madre of Texas supports the most extensive seagrass meadows in the western Gulf of Mexico, In 1988 seagrasses covered 730 km 2 or about three-quarters of the embayment. Halodule wrightii dominated the entire upper laguna, and total biomass was quite uniform near 160 g˙m -2 throughout. Four species shared dominance in the lower laguna. Where present mean biomass of Thalassia testudinum was 373 g˙m -2 ; Syringodium filiforme , 138 g˙m -2 ; Halodule wrightii , 78 g˙m -2 ; and Halophila engelmannii , 6 g˙m -2 . Macroalgae were widespread, at 71 g˙m -2 where present. Halodule wrightii was dominant and biomass was low on sand flats of the barrier island separating the laguna from the gulf. Halophila engelmannii was limited to the deep edges of meadows. Biomass >300 g˙m -2 was limited to one extensive T. testudinum meadow at the south end of the laguna at all vegetated depths and two small areas with S. filiforme dominant at intermediate depths. Laguna Madre was similar in biomass to the two regions of extensive development of seagrasses in the eastern gulf: the Big Bend region of Florida (Iverson and Bittaker, 1986) and Florida Bay (Iverson and Bittaker, 1986; Zieman, et al., 1989). The laguna differed from the eastern gulf sites in more turbid waters and much shallower maximum depths of occurrence of seagrasses (<2 m compared to 8–11 m), higher contribution of H. wrightii to system-wide biomass (although H. wrightii 's share has rapidly diminished in Laguna Madre as it has been displaced by S. filiforme and T. testudinum [Quammen and Onuf, 1993]), and much higher macroalgal biomass (limited to the section of the lower laguna receiving agricultural inflows). Similarities in the environments of Laguna Madre and inner Florida Bay suggest that, if cover and biomass of Thalassia continue to increase, the laguna may become vulnerable to mass mortalities as are now occurring in Florida Bay.

Texas↗
USGS2007

Deep-sea scleractinian coral age and depth distributions in the northwest Atlantic for the last 225,000 years

Deep-sea corals have grown for over 200,000 yrs on the New England Seamounts in the northwest Atlantic, and this paper describes their distribution both with respect to depth and time. Many thousands of fossil scleractinian corals were collected on a series of cruises from 2003-2005; by contrast, live ones were scarce. On these seamounts, the depth distribution of fossil Desmophyllum dianthus (Esper, 1794) is markedly different to that of the colonial scleractinian corals, extending 750 m deeper in the water column to a distinct cut-off at 2500 m. This cut-off is likely to be controlled by the maximum depth of a notch-shaped feature in the seamount morphology. The ages of D. dianthus corals as determined by U-series measurements range from modern to older than 200,000 yrs. The age distribution is not constant over time, and most corals have ages from the last glacial period. Within the glacial period, increases in coral population density at Muir and Manning Seamounts coincided with times at which large-scale ocean circulation changes have been documented in the deep North Atlantic. Ocean circulation changes have an effect on coral distributions, but the cause of the link is not known. ?? 2007 Rosenstiel School of Marine and Atmospheric Science of the University of Miami.

Bulletin of Marine Science↗
USGS2010

Nearshore concentration of pink shrimp (Farfantepenaeus duorarum) postlarvae in northern Florida bay in relation to nocturnal flood tide

We address the question of whether the low abundance of juvenile pink shrimp Farfantepenaeus duorarum (Burkenroad, 1939) in northern-central Florida Bay results from (i) limiting environmental conditions, (ii) a reduced postlarval transport, or (iii) both. To explore this question, postlarvae were collected during the new moon in both summer and fall of 2004 and 2005 at six stations located on a transect from the bay's western margin to its interior. The highest concentrations of postlarvae occurred at two mid-transect stations located in shallow channels with moderate tidal amplitudes (15-20 cm) and dense seagrass beds. At the two interiormost stations postlarval concentrations decreased together with a reduction of the tidal amplitude (= 1 cm). Estimates of the cumulative flood-tide displacement with the semidiurnal M 2 constituent indicated that the tide moves a maximum of 15 km in four nights, a distance that corresponds to the location of the highest concentrations of postlarvae. The size of postlarvae also reached a maximum at the location of the highest concentrations of postlarvae. Results suggest that postlarvae move into the bay's interior by a cumulative flood tidal process, advancing onshore during successive nights as far as they can go with the tide. Analyses indicate that, in addition to the tidal amplitude, cross-shelf wind stress and salinity also affect the concentrations of postlarvae. Peaks of postlarvae occurred at times of low salinity and strong southeasterly winds. While tidal transport appears to be insufficient for postlarvae to reach Florida Bay's interior, salinity and winds may also contribute to the observed distribution patterns of early pink shrimp recruits. ?? 2010 Rosenstiel School of Marine and Atmospheric Science of the University of Miami.

Bulletin of Marine Science↗
USGS2015

Oil-particle interactions and submergence from crude oil spills in marine and freshwater environments: review of the science and future research needs

Oil-particle interactions and oil submergence are of much interest to oil spill responders and scientists, especially as transportation of light and heavy crude oils increases in North America&rsquo;s coastal marine and freshwater environments. This report contains an up-to-date review of the state of the science for oil-particle aggregates (OPAs), in terms of their formation and stability which may alter the transport, fate, and toxicity of the residual oil and, hence, its level of ecological risk. Operational considerations&mdash;detection, containment, and recovery&mdash;are discussed. Although much is known about oil-particle interactions in coastal marine environments, there remains a need for additional science on methods to detect and quantify the presence of OPAs and to understand their effects on containment and recovery of oil spilled under various temperature regimes and in different aquatic habitats including freshwater environments.

Open-File Report↗
USGS2018

International Society for Aeolian Research Distinguished Career Award, 2018 Joseph M. Prospero, Dr. Professor Emeritus, University of Miami

It is a pleasure and an honor to present Dr. Joseph M. Prospero of the University of Miami with the International Society for Aeolian Research(ISAR) Distinguished Career Award for 2018. Joe was born at home in Pottstown, Pennsylvania, one of three sons of Italian immigrant parents. He got interested in science, and particularly chemistry, not only out of curiosity, but also because of “...all the usual things. Color reactions...explosions....” Thus, his earliest experimental work was done with a Lionel Chem-Lab set in its classic chrome-yellow wooden box. Joe had parents who, despite their own lack of education,encouraged learning for Joe and his brothers through reading and education. He earned his B.S. in chemistry at Ursinus College in Collegeville, Pennsylvania in 1956. From there he went on to Princeton University for graduate school, studying radiochemistry and nuclear spectroscopy, receiving his M.A. in 1959 and his Ph.D. in 1963. On the encouragement of George Reynolds (a physicist at Princeton), Joe began his career at the Rosenstiel School of Marine and Atmospheric Science at the University of Miami in 1963. He has been studying dust everywhere on the planet–both on land and in the oceans–ever since.His research has been published in more than 170 papers and they are highly cited, showing the importance of dust in an astonishing diversity of the Earth’s natural systems, as well as its importance to human society.

Aeolian Research↗
USGS2000

Diagenetic fate of organic contaminants on the Palos Verdes Shelf, California

Municipal wastes discharged through deepwater submarine outfalls since 1937 have contaminated sediments of the Palos Verdes Shelf. A site approximately 6–8 km downcurrent from the outfall system was chosen for a study of the diagenetic fate of organic contaminants in the waste-impacted sediments. Concentrations of three classes of hydrophobic organic contaminants (DDT+metabolites, polychlorinated biphenyls (PCBs), and the long-chain alkylbenzenes) were determined in sediment cores collected at the study site in 1981 and 1992. Differences between the composition of effluent from the major source of DDT (Montrose Chemical) and that found in sediments suggests that parent DDT was transformed by hydrolytic dehydrochlorination during the earliest stages of diagenesis. As a result, p , p ′-DDE is the dominant DDT metabolite found in shelf sediments, comprising 60–70% of ΣDDT. The p , p -DDE/ p , p ′-DDMU concentration ratio decreases with increasing sub-bottom depth in sediment cores, indicating that reductive dechlorination of p , p ′-DDE is occurring. Approximately 9–23% of the DDE inventory in the sediments may have been converted to DDMU since DDT discharges began ca. 1953. At most, this is less than half of the decline in p , p ′-DDE inventory that has been observed at the study site for the period 1981–1995. Most of the observed decrease is attributable to remobilization by processes such as sediment mixing coupled to resuspension, contaminant desorption, and current advection. Existing field data suggest that the in situ rate of DDE transformation is 10 2 –10 3 times slower than rates determined in recent laboratory microcosm experiments (Quensen, J.F., Mueller, S.A., Jain, M.K., Tiedje, J.M., 1998. Reductive dechlorination of DDE to DDMU in marine sediment microcosms. Science, 280, 722–724.). This explains why the DDT composition (i.e. o , p ′-, p , p ′-isomers of DDE, DDD, DDT) of sediments from this site have not changed significantly since at least 1972. Congener-specific PCB compositions in shelf sediments are highly uniform and show no evidence of diagenetic transformation. Apparently, the agents/factors responsible for reductive dechlorination of DDE are not also effecting alteration of the PCBs. Two types of long-chain alkylbenzenes were found in the contaminated sediments. Comparison of chain length and isomer distributions of the linear alkylbenzenes in wastewater effluent and surficial sediment samples indicate that these compounds undergo biodegradation during sedimentation. Further degradation of the linear alkylbenzenes occurs after burial despite relatively invariant isomer compositions. The branched alkylbenzenes are much more persistent than the linear alkylbenzenes, presumably due to extensive branching of the alkyl side chain. Based on these results, p , p ′-DDE, PCBs, and selected branched alkylbenzenes are sufficiently persistent for use in molecular stratigraphy. The linear alkylbenzenes may also provide information on depositional processes. However, their application as quantitative molecular tracers should be approached with caution.

California↗
USGS2016

Walter Rowe Courtenay, Jr. (1933–2014)

WALTER R. COURTENAY, JR., ichthyologist and retired professor, Florida Atlantic University, Boca Raton, Florida, died in Gainesville, Florida, on 30 January 2014 at age 80. Walt was born in Neenah, Wisconsin, on 6 November 1933, son of Walter and Emily Courtenay. Walt's interest in fish began at a young age as evidenced by a childhood diary in which at 13 years of age he wrote about his first catch&mdash;a two-and-a-half pound &ldquo;pike&rdquo; from Lake Winnebago. When Walt turned ten, the family moved from Wisconsin to Nashville, Tennessee, the move precipitated by his father accepting a position as pastor of the First Presbyterian Church. During those early days in Nashville, Walt's father would take summers off and travel to Michigan to teach at Camp Miniwanca along the shore of Lake Michigan where father and son honed their angling skills. It was also at that time Walt's father had definite views on what his son should be doing in adult life&mdash;in Walt's case it was to become a medical doctor. However, his Woods Hole internship in marine biology and oceanography toward the end of his undergraduate years was a transformative experience for him so much so that he abandoned all ideas of becoming a medical doctor and instead specialized in ichthyology and oceanography. Apart from the inherent interest and opportunities Woods Hole opened to him, being back at the shore of a large body of water, in this case the Atlantic Ocean, was far more interesting than sitting in lectures on organic chemistry. With that, Walt completed his B.A. degree at Vanderbilt University in 1956. In 1960 while in graduate school in Miami, Walt met and married Francine Saporito, and over the next several years had two children, Walter III and Catherine. He went on to receive his M.S. in 1961 from The Rosenstiel School of Marine and Atmospheric Science at the University of Miami on the systematics of the genus Haemulon (grunts) and his Ph.D. degree in 1965 working under his advisor C. Richard &ldquo;Dick&rdquo; Robins, also at Miami, with his dissertation entitled &ldquo;Atlantic Fishes of the Genus Rypticus (Grammistidae): Systematics and Osteology.&rdquo; Dick and wife Catherine Robins, also a fellow biologist, thought of him as a great friend to have. They fondly recalled that those of us who knew Walt in his early grad student days valued his sense of humor and unmistakable laugh, much of which was directed at bureaucratic foolishness and pomposity. However, he also had a very serious side when it came to justice and responsibility.

Copeia↗
USGS1983

Multichannel seismic measurements on the northern edge of the Bahaman-Cuban collision zone

This paper presents geophysical data obtained, in the western reaches of the Old Bahama Channel separating Cuba and the Bahamas (Figure 1). These data were collected as part of an ongoing investigation of Caribbean and Bahaman geology primarily conducted by University of Miami and the U.S. Geological Survey (USGS). The work was done on the R/V Gilliss of Rosenstiel School of Marine and Atmospheric Sciences, (RSMAS), University of Miami. The scientific party included members of the Woods Hole Oceanographic Institute (WHOI) and RSMAS.

Open-File Report↗
USGS2007

Seasonal fish community variation in headwater mangrove creeks in the southwestern everglades: An examination of their role as dry-down refuges

The connectivity between the fish community of estuarine mangroves and that of freshwater habitats upstream remains poorly understood. In the Florida Everglades, mangrove-lined creeks link freshwater marshes to estuarine habitats downstream and may act as dry-season refuges for freshwater fishes. We examined seasonal dynamics in the fish community of ecotonal creeks in the southwestern region of Everglades National Park, specifically Rookery Branch and the North and Watson rivers. Twelve low-order creeks were sampled via electrofishing, gill nets, and minnow traps during the wet season, transition period, and dry season in 2004-2005. Catches were greater in Rookery Branch than in the North and Watson rivers, particularly during the transition period. Community composition varied seasonally in Rookery Branch, and to a greater extent for the larger species, reflecting a pulse of freshwater taxa into creeks as marshes upstream dried periodically. The pulse was short-lived, a later sample showed substantial decreases in freshwater fish numbers. No evidence of a similar influx was seen in the North and Watson rivers, which drain shorter hydroperiod marshes and exhibit higher salinities. These results suggest that head-water creeks can serve as important dry-season refugia. Increased freshwater flow resulting from Everglades restoration may enhance this connectivity. ?? 2007 Rosenstiel School of Marine and Atmospheric Science of the University of Miami.

Conference Paper↗
USGS2009

Satellite telemetry of marine megavertebrates: The coming of age of an experimental science

Wildlife telemetry research has expanded greatly in the last 2 decades, with the application of satellite tracking and archival logging technologies to study the ecology and conservation of marine mammals, birds, fishes, and turtles. Widespread and expanding use of satellite tracking to study movements and habitats of marine megavertebrates warrants a review of progress to date and a discussion of challenges facing this rapidly evolving research field. To this end, we reviewed the satellite telemetry literature of air-breathing marine taxa (i.e. birds, mammals, turtles) over the 20 yr time period from 1987 to 2006. This review yielded 92 studies with a wide taxonomic representation: 47 seabirds, 23 sea turtles, and 22 marine mammals. Here we critically evaluate these articles to assess progress in satellite tracking of marine megavertebrates in terms of (1) objectives and approach, (2) experimental design, and (3) reporting of results. The overall trends revealed increases in the duration and scope of tracking studies, yet improvements on experimental design and reporting are needed to facilitate comparisons across studies and species. While inherent ecological differences influence the focus and methods of taxon-specific studies, this review highlights specific areas in need of improvement and provides general suggestions for future tracking studies of marine megavertebrates.

Endangered Species Research↗
USGS2002

Continental shelf GIS for the Monterey Bay National Marine Sanctuary

A marine sanctuary is an environment where the interests of science and society meet. Land and marine managers need access to the best scientific data available that describe the environment and environmental processes in sanctuaries. The sidescan sonar imagery, bathymetry, sample analyses and other data discussed in the papers in this volume have been made available as a U.S. Geological Survey CDROM publication. ?? 2002 Elsevier Science B.V. All rights reserved.

Marine Geology↗