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Behavioral Ecology Of Two Teal Species (Blue-Winged Teal, Anas Discors, And Green-Winged Teal, Anas Crecca) Overwintering In Marshes Of Coastal Louisiana, Usa, Gary R. Gaston, Jeanne C. Nasci Jan 1994

Behavioral Ecology Of Two Teal Species (Blue-Winged Teal, Anas Discors, And Green-Winged Teal, Anas Crecca) Overwintering In Marshes Of Coastal Louisiana, Usa, Gary R. Gaston, Jeanne C. Nasci

Gulf and Caribbean Research

Feeding and other dominant activities of Blue-winged Teal (BWT, Anas discors) and Green-winged Teal (GWT, Anas crecca) were compared from October 1987 to March 1988 in southwestern Louisiana, USA. Three observation towers were constructed near similar intermediate marsh habitats in areas where BWT and GWT concentrated for feeding. These observation towers allowed activities of the two species to be compared throughout the nonbreeding season. Although BWT and GWT often fed together, time spent in various activities differed. Feeding was the most frequent activity of both BWT(64.5%) and GWT (55.3%), but BWT spent more time feeding (P < 0.01) and alert (P < 0.05), but spent less (P < 0.01) time resting than GWT. Within each species there were differences in activity budgets among daily time blocks and among months, but few differences among the three habitats studied. Temperature and light intensity were correlated with resting (+), feeding (-), locomotion (-), and preening (+). Daily and monthly activity budgets of BWT and GWT were similar, as were ingested foods, suggesting that these two species used the study areas primarily for foraging, and left the areas for other activities. Predation and diminished resources during late winter may have affected activities of BWT and GWT as well.


Mat Movement In Coastal Louisiana Marshes: Effect Of Salinity And Inundation On Vegetation And Nutrient Levels, Christopher Martin Swarzenski Jul 1992

Mat Movement In Coastal Louisiana Marshes: Effect Of Salinity And Inundation On Vegetation And Nutrient Levels, Christopher Martin Swarzenski

Biological Sciences Theses & Dissertations

The present research compared and contrasted the physical structure of floating and rooted marshes, their differing responses to open-water salinities and inundation, as well as the nutrient distribution in the porewaters and sediment. The effects of the physical differences in the two marsh types on the ocurrence of the dominant emergent vegetation was discussed.

The main difference in physical structure of the two marsh types was the presence of a mineral, non-buoyant layer at 25-45 cm depth in the rooted marsh, which could serve as an anchor for the overlying highly organic mat layer found in both marsh types. Porewater …


Whooping Cranes In Southwest Louisiana: History And Human Attitudes, Gay M. Gomez Jan 1992

Whooping Cranes In Southwest Louisiana: History And Human Attitudes, Gay M. Gomez

Proceedings of the North American Crane Workshop

When whooping cranes (Grus americana) inhabited southwest Louisiana's coastal marshes, residents viewed them as a food source and a crop pest, and shooting was commonplace. Local attitudes have changed as a result of education, stricter law enforcement, and decreased dependence on wildlife for subsistence, but hunting remains widespread. A 1977 proposal to reintroduce whooping cranes to southwest Louisiana generated strong opposition from the Louisiana Wild Life and Fisheries Commission (now Louisiana Department of Wildlife and Fisheries), based on concerns about critical habitat and its likely impact on waterfowl hunting and other traditional marsh uses. These concerns remain, though …


Survey And Reconnaissance Of Sea Turtles In The Northern Gulf Of Mexico, Larry Ogren Jan 1989

Survey And Reconnaissance Of Sea Turtles In The Northern Gulf Of Mexico, Larry Ogren

United States Department of Commerce: Staff Publications

This is a report on the results of an aerial survey of nesting beaches conducted during the period from May 16, 1977 to August 11, 1977. The area covered included the barrier beaches and offshore islands from the Florida-Alabama state line to the Rio Grande, Texas. Additional historical information is provided in order to compare current nesting activity with previous years as well as anecdotal observations on the occurrence of sea turtles in this region.


A Preliminary Checklist Of Epiphytic And Benthic Marine Diatoms Of Louisiana, Robert S. Maples Jan 1984

A Preliminary Checklist Of Epiphytic And Benthic Marine Diatoms Of Louisiana, Robert S. Maples

Gulf and Caribbean Research

A checklist of diatoms collected from the various habitats in coastal salt marshes, estuaries, and nearshore Gulf waters of Louisiana has been compiled for the first time. The checklist includes 193 taxa (species and their varieties) in 38 genera. The largest number of taxa are species of Navicula and Nitzschia with 46 and 36, respectively. Future studies of the varied habitats along the Louisiana coast should result in many new additions to this preliminary checklist.


Community Structure Of Diatoms Epiphytic On Pneumatophores Of The Black Mangrove, Avicennia Germinans, In A Louisiana Salt Marsh, Robert S. Maples Jan 1983

Community Structure Of Diatoms Epiphytic On Pneumatophores Of The Black Mangrove, Avicennia Germinans, In A Louisiana Salt Marsh, Robert S. Maples

Gulf and Caribbean Research

The taxonomy, diversity, and similarity of diatom assemblages epiphytic on pneumatophores of black mangrove, Avicennia germinans (L.) L., in southeastern Louisiana were investigated. A total of 109 taxa representing 27 genera were identified in samples from five sites. The most abundant taxa were Nitzschia brittonii Hagelstein, Nitz. frustulum (Kutz.) Grun., Navicula diserta Hust., Denticula subtilis Grun., and Amphora tenuissima Hust. Comparisons with previous studies indicate that the diatom flora epiphytic on A. germinans in this study is much more characteristic of temperate salt marshes than of subtropical mangrove communities.


Effects Of Saltwater Intrusion From The Inner Harbor Navigation Canal On The Benthos Of Lake Pontchartrain, Louisiana, Jane A. Junot, Michael A. Poirrier, Thomas M. Soniat Jan 1983

Effects Of Saltwater Intrusion From The Inner Harbor Navigation Canal On The Benthos Of Lake Pontchartrain, Louisiana, Jane A. Junot, Michael A. Poirrier, Thomas M. Soniat

Gulf and Caribbean Research

A study of the benthos of southern Lake Pontchartrain, Louisiana, was conducted from July 1976 to July 1978. Seven offshore stations and three stations in the New Orleans Marina complex were sampled seasonally. Offshore stations formed a transect from the Lake Pontchartrain Causeway to the Inner Harbor Navigation Canal (I.H.N.C.). A west to east gradient of increasing salinity and salinity stratification was evident.

Faunal differences among stations were assessed using indices of diversity, biological dominance, pollution, and station homogeneity. The fauna of the marina stations had a low species diversity and was dominated by annelids, indicative of a stressed environment. …


Trends In Ex-Vessel Value And Size Composition Of Reported May - August Catches Of Brown Shrimp And White Shrimp From The Texas, Louisiana, Mississippi, And Alabama Coasts, 1960-1978, Charles Wax Caillouet, Dennis Brian Koi Jan 1981

Trends In Ex-Vessel Value And Size Composition Of Reported May - August Catches Of Brown Shrimp And White Shrimp From The Texas, Louisiana, Mississippi, And Alabama Coasts, 1960-1978, Charles Wax Caillouet, Dennis Brian Koi

Gulf and Caribbean Research

Exponential models were used to characterize (1) ex-vessel value (in dollars) per shrimp by size category (count; i.e., number of shrimp per pound, heads off); (2) size composition (expressed as cumulative weight of the catch in pounds, heads off, by size category); and (3) ex-vessel value composition (expressed as cumulative ex-vessel value, in dollars, of the catch by size category) for reported May-August catches (inshore and offshore combined) of brown shrimp (Penaeus aztecus) and white shrimp (P. setiferus) from the Texas, Louisiana, Mississippi, and Alabama coasts (statistical areas 10-21) from 1960 to 1978. Exponents of the …


Effects Of 1973 Floodwaters On Plankton Populations In Louisiana And Mississippi, Suzanne R. Hawes, Harriet M. Perry Jan 1978

Effects Of 1973 Floodwaters On Plankton Populations In Louisiana And Mississippi, Suzanne R. Hawes, Harriet M. Perry

Gulf and Caribbean Research

Studies to assess the impact of floodwater diversion on plankton populations in coastal waters of Mississippi and Louisiana were conducted from 23 April 1973 through 13 July 1973. Fixed stations in Lake Pontchartrain, Lake Borgne and western Mississippi Sound were sampled once in April, twice in May and June, and once in July. Stations in Terrebonne Parish, Louisiana were visited once in May, June and July.

Data are presented on changes in the species composition of zooplankton subsequent to the opening of the Bonnet Card and Morganza floodways. The hydrographic conditions at the time of sampling are discussed.


A Telemetric Study Of The Red Fox In Agricultural Areas Of Southeast Louisiana, George Washington Taylor Jul 1972

A Telemetric Study Of The Red Fox In Agricultural Areas Of Southeast Louisiana, George Washington Taylor

LSU Historical Dissertations and Theses

The primary study objective was to determine the daily activities of red foxes on agricultural habitat It was also hoped to learn something of the fox's foo preferences and predation on quail, rabbits, deer, an poultry. Information was also desired on optimum met ods of capture, the incidence of rabies, and the use Tranimul and Sernyl as immobilizing drugs. Fifteen red foxes (Vulpes fulva) were trapped during late winter on Louisiana State University property near Baton Rouge, Louisiana. Six foxes were equipped with radio transmitters and their movements were monitored by means of portable VHF radio receivers and hand-held antennas. …


A Study Of Syngnathus Scovelli In Fresh Waters Of Louisiana And Salt Waters Of Mississippi, Edward Caldwell Whatley Jan 1969

A Study Of Syngnathus Scovelli In Fresh Waters Of Louisiana And Salt Waters Of Mississippi, Edward Caldwell Whatley

Gulf and Caribbean Research

A breeding population of Syngnathus scovelli was discovered in 1960 in Lake St. John near Ferriday, Louisiana, which is over 300 river miles from the Gulf of Mexico by the shortest possible route. Although S. scovelli has been known to be euryhaline, this constitutes the first record of a breeding population in fresh water.

This study encompassed the period from July 1960 through February 1966. During this time S. scovelli were maintained for varying periods of time in fresh water aquaria. The longest period of time any one specimen lived in captivity was from 29 September 1960 until 16 November …


A Seasonal Ecological Study Of Foraminifera From Timbalier Bay, Louisiana, Robert P. Waldron Jan 1963

A Seasonal Ecological Study Of Foraminifera From Timbalier Bay, Louisiana, Robert P. Waldron

Gulf and Caribbean Research

This study concerns the ecological habits of living Foraminifera from a shallow Louisiana coastal bay during a period of ten months. It is a part of an extensive study undertaken by the Coastal Studies Institute of Louisiana State University to determine the effect of chemical and physical properties of water upon marine life in a large, open bay over an extended period of time. Samples were collected monthly from established locations for the chemical, biological and foraminiferal determinations. Results of the chemical and biological studies will be published by the respective investigators in subsequent papers.

The period of time covered …