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Relationship Of Channel Maintenance Flows To Whooping Crane Use Of The Platte River, Craig A. Faanes, David B. Bowman Jan 1992

Relationship Of Channel Maintenance Flows To Whooping Crane Use Of The Platte River, Craig A. Faanes, David B. Bowman

Proceedings of the North American Crane Workshop

Periodic high flows in the Platte River are necessary to scour vegetation and redistribute sediment in the stream channel. Peak and mean annual flows have been reduced by as much as 70% from pre-development times, but channel maintenance flows still occur, although at a much reduced frequency and magnitude of occurrence. Use of the Platte River by migrant whooping cranes (Grus americana) in recent years appears to be related to the recent occurrence of flows in excess of 8,000 cfs for 5 or more consecutive days.


Sex Ratios In Bobcat Populations, C. Renn Tumlison, V. Rick Mcdaniel Jan 1988

Sex Ratios In Bobcat Populations, C. Renn Tumlison, V. Rick Mcdaniel

Journal of the Arkansas Academy of Science

Reported sex ratios in bobcat populations have suggested great variation ranging from strong male bias to strong female bias. Explanations offered for these observations have included factors of mobility, activity, behavior, inaccurate data collection, hunting pressure, and population density. Ratios are probably most representative during the winter, when females are no longer under constraints of parental care. Sex determination should be made by experienced observers and preferably through internal examination. The most productive direction for interpretation of validated ratios appears to be in terms of population density, hunting pressure, and the timing of harvest.


Behavioral Feeding Specialization In Pinaroloxias Inornata, The “Darwin's Finch” Of Cocos Island, Costa Rica, Tracey K. Werner, Thomas W. Sherry Apr 1987

Behavioral Feeding Specialization In Pinaroloxias Inornata, The “Darwin's Finch” Of Cocos Island, Costa Rica, Tracey K. Werner, Thomas W. Sherry

Dartmouth Scholarship

As a population, Cocos Finches exhibit a broad range of feeding behaviors spanning those of several families of birds on the mainland, while individuals feed as specialists year-round. Although this extreme intraspecific variability occurs as predicted in a tropical oceanic island environment, these specializations challenge contemporary ecological theory in that they are not attributable to individual differences in age, sex, gross morphology, or opportunistic exploitation of patchy resources. Instead, they appear to originate and be maintained behaviorally, possibly via observational learning. This phenomenon adds another direction to the evolutionary radiation of the Darwin's Finches and underscores the necessity for detailed …


Comparison Of The Symbiotic Fauna Of The Family Plethodontidae In The Ouachita Mountains Of Western Arkansas, Douglas A. Winter, Wojciech M. Zawada, Arthur A. Johnson Jan 1986

Comparison Of The Symbiotic Fauna Of The Family Plethodontidae In The Ouachita Mountains Of Western Arkansas, Douglas A. Winter, Wojciech M. Zawada, Arthur A. Johnson

Journal of the Arkansas Academy of Science

During the spring of 1985, 101 salamanders representing six host species (29 Plethodon ouachitae, 25 P. caddoensis, 6 P. fourchensis, 23 P. serratus, 13 Desmognathus brimleyorum, and 5 P. glutinosus glutinosus) were collected from six localities in three counties in Arkansas (Polk, Scott, and Montgomery) and examined for symbionts. With the exception of Hannemania dunni, all symbionts recovered from the first five species listed constitute new host records, and the endoparasitic fauna in all species establish new locality records. Examinations revealed one or more species of parasites in 82% of the hosts. Eight species of symbionts (3 nematode, 1 trematode, …


An Ecological Study Of The Troglobitic Cirolanid Isopod Antrolana Lira Bowman From Madisons Saltpetre Cave And Stegers Fissure, Augusta Co., Virginia, T. Lynn Collins Jul 1982

An Ecological Study Of The Troglobitic Cirolanid Isopod Antrolana Lira Bowman From Madisons Saltpetre Cave And Stegers Fissure, Augusta Co., Virginia, T. Lynn Collins

Biological Sciences Theses & Dissertations

An ecological study of the troglobitic cirolanid isopod, Antrolana lira Bowman, was begun in August 1979 and continued through September 1980. The isopod is restricted to two phreatic lakes in Madisons Saltpetre Cave and one phreatic lake in nearby Stegers Fissure, Augusta Co., Virginia.

All three phreatic lakes were scuba dived and surveyed. No direct connections were found between the lakes. However, physical similarities suggest that the lakes are made up of the same body of phreatic water.

Random samples were taken monthly and seasonally from the east lake in Madisons Saltpetre Cave and the lake in Stegers Fissure. Specimens …


Estimation Of Harvest Rate Of Black Bears From Age And Sex Data, David Fraser, James F. Gardner, George B. Kolenosky, Stewart Strathearn Apr 1982

Estimation Of Harvest Rate Of Black Bears From Age And Sex Data, David Fraser, James F. Gardner, George B. Kolenosky, Stewart Strathearn

Wildlife Population Management Collection

No abstract provided.


A Structural Analysis Of Phytoplankton In The Chesapeake Bay Plume And Adjacent Shelf Waters, Charles K. Rutledge Apr 1982

A Structural Analysis Of Phytoplankton In The Chesapeake Bay Plume And Adjacent Shelf Waters, Charles K. Rutledge

Biological Sciences Theses & Dissertations

Community structures of phytoplankton populations from the southern portion of the Chesapeake Bight were examined and associated to real and environmental spaces. The sampling design was specifically intended to examine the small scale three dimensional structure of the Chesapeake Bay plume as characterized by its phytoplankton populations. The phytoplankton were sampled at 101 stations, non-synoptically, over a five day period in mid-June, 1980.

Several multivariate numerical techniques were used to determine the relationships between the phytoplankton species distributions and pattern the low salinity plume distribution. A pattern of distribution which approximated the salinity plume resulted from several clustering procedures. Environmental …


Macrobenthic Communities Of An Industrialized Seaport Ecosystem: The Southern Branch Of The Elizabeth River, Virginia, Steven D. Hawthorne Apr 1980

Macrobenthic Communities Of An Industrialized Seaport Ecosystem: The Southern Branch Of The Elizabeth River, Virginia, Steven D. Hawthorne

Biological Sciences Theses & Dissertations

Macrobenthic invertebrates of an industrialized seaport ecosystem were studied seasonally from October, 1977 through July, 1978. Five stations were selected along the Southern Branch of the Elizabeth River, Virginia. The stations ranged from an area of heavy industrialization to a non-urbanized environment. At each station, bottom water was measured for salinity, temperature, dissolved oxygen, and pH. Within each sampling area, macrobenthic infauna! invertebrates were collected from in and out of channel sites along with sediment samples for various types of physicochemical analysis.

Community structure was spatially homogeneous at station sites and throughout the stations along the River. Slightly acidic pH …


Information From The Elephant Interest Group Questionnaire, Elephant Editors May 1979

Information From The Elephant Interest Group Questionnaire, Elephant Editors

Elephant

Elephant-related activities of answering respondents to the newsletter's questionnaire.


Bibliography, Elephant Editors May 1979

Bibliography, Elephant Editors

Elephant

Updates to the selected bibliography covering references from 1970 - mid-1979.


Animal-Sediment Relationship Study Of The Western Branch Of The Lynnhaven River, Charles Perry Seymour Jan 1979

Animal-Sediment Relationship Study Of The Western Branch Of The Lynnhaven River, Charles Perry Seymour

Biological Sciences Theses & Dissertations

The animal-sediment relationships of the marine benthic infauna of an estuarine river system, Lynnhaven River, Virginia Beach, Virginia, were studied at six sites, sampled bimonthly for one year. Six species were found to dominate all of the sampling periods and sites for the year. The greatest number of individuals, biomass, and species were found at the sand sites. Deposit feeders were recorded in greater number than suspension feeders at both the sand and the mud sites.

Cluster and nodal analyses were successful in demonstrating animal-sediment relationships for the intertidal regions of the river system.


Some Ecological Relations Of Fairy Shrimps In Alkaline Habitats Of Nebraska, D. B. Mccarraher Jan 1970

Some Ecological Relations Of Fairy Shrimps In Alkaline Habitats Of Nebraska, D. B. Mccarraher

Nebraska Game and Parks Commission: Staff Research Publications

Ecological studies on the distribution of fairy shrimps have been made from 246 sites in the sandhills region of Nebraska. New records for Nebraska have been established for Artemia salina, Branchinecta campestris, B. lindahli, B. mackini and Cyzicus mexicanus. Seasonal populations of shrimp have been located in habitats containing permanent fish populations. Water mineralization was the dominant environmental condition related to the distribution of phyllopods with sodium and potassium compounds predominating in the strongly alkaline lakes. Several of the Artemia lakes were classified as hydroxide sites. Many of the alkaline ponds, where B. lindahli and B. campestris flourish, are …


An Estimate Of Winter Utilization Of The Cedar Creek Natural History Area By The White-Tailed Deer, L. D. Frenzel Jr. Jan 1965

An Estimate Of Winter Utilization Of The Cedar Creek Natural History Area By The White-Tailed Deer, L. D. Frenzel Jr.

Journal of the Minnesota Academy of Science

Estimates of utilization of the Cedar Creek Natural History Area by the white-toiled deer (Odocoileus virginianus borealis) during the winters of 1963 and 1964 were mode using the deer-drive method. The 1964 estimate is considered the more realistic index of winter utilization by deer of the area because of increased efficiency of the drive, weather conditions favoring deer-drive technics, and agreement with results of pellet-count studies mode independently on the area.


Comparison Of Spider Populations Of Ground Stratum In Arkansas Pasture And Adjacent Cultivated Field, W. H. Whitcomb, Harriet Exline, Maxine Hite Jan 1963

Comparison Of Spider Populations Of Ground Stratum In Arkansas Pasture And Adjacent Cultivated Field, W. H. Whitcomb, Harriet Exline, Maxine Hite

Journal of the Arkansas Academy of Science

Of 64 species of spiders taken from the ground stratum of an Arkansas pasture and adjoining cotton field, only 26 were common to both. Twenty-two were collected only in the cotton field; 16, only in the pasture. Many of the 18 species of lycosids were taken in greater numbers in the cultivated field, especially Pardosa milvina and Lycosa helluo. Eight species of lycosids were found only in the cotton field; two, only in the pasture. Only Schizocosa avida, of the better represented lycosids, appeared to show no preference. Similar relationships are given for dictynids, erigonids, linyphiids, oxyopids, gnaphosids, clubionids, thomisids, …


A Distributional Survey Of The Birds Of Sonora, Mexico, A. J. Van Rossem Oct 1945

A Distributional Survey Of The Birds Of Sonora, Mexico, A. J. Van Rossem

Occasional Papers of the Museum of Natural Science, Louisiana State University

No abstract provided.