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

Ecology and Evolutionary Biology Commons™

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

Population Biology

Institution
Keyword
Publication Year
Publication
Publication Type
File Type

Articles 3661 - 3690 of 3785

Full-Text Articles in Ecology and Evolutionary Biology

Contributions To The Reproductive Biology And Natural History Of The Pirateperch, Aphredoderus Sayanus, Edward O. Murdy Jul 1977

Contributions To The Reproductive Biology And Natural History Of The Pirateperch, Aphredoderus Sayanus, Edward O. Murdy

Biological Sciences Theses & Dissertations

The purpose of this study was to describe the micro and macro-anatomy of the reproductive system and the testicular and ovarian development in Aphredoderus sayanus.

Specimens were collected at least once a month from September, 1976, through May, 1977, in Cypress Pond, a part of the Dismal Swamp drainage, outside of Suffolk, Virginia. Forty-three specimens had their gonads examined histologically, of these 13 were males, 29 were females and in one specimen the sex was not determinable.

Aphredoderus sayanus is a spring spawner, spent gonads were found on and after April 13, 1977. Gonads began to ripen in the …


Analysis Of The Capture-Recapture Method Of Determining Fish Population Size In A Pond Community, Richard E. Hall Jan 1977

Analysis Of The Capture-Recapture Method Of Determining Fish Population Size In A Pond Community, Richard E. Hall

Masters Theses

No abstract provided.


Revision Of The South American Colubrid Snakes Of The Helicops Pastazae Complex, Douglas A. Rossman Apr 1976

Revision Of The South American Colubrid Snakes Of The Helicops Pastazae Complex, Douglas A. Rossman

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

No abstract provided.


Karyotypic Variation In Oryzomyine Rodents (Cricetinae) With Comments On Chromosomal Evolution In The Neotropical Cricetine Complex, Alfred L. Gardner, James L. Patton Apr 1976

Karyotypic Variation In Oryzomyine Rodents (Cricetinae) With Comments On Chromosomal Evolution In The Neotropical Cricetine Complex, Alfred L. Gardner, James L. Patton

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

No abstract provided.


The Distributional Status Of Some Peruvian Mammals, Alfred L. Gardner Apr 1976

The Distributional Status Of Some Peruvian Mammals, Alfred L. Gardner

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

No abstract provided.


Variation In The Ecology Morphology And Behavior Of The Troglobitic Amphipod Crustacean Crangonyx Antennatus Packard (Crangonchidae) From Different Habitats, Gary Wayne Dickson Apr 1976

Variation In The Ecology Morphology And Behavior Of The Troglobitic Amphipod Crustacean Crangonyx Antennatus Packard (Crangonchidae) From Different Habitats, Gary Wayne Dickson

Biological Sciences Theses & Dissertations

Populations of the troglobitic amphipod Crangonyx antennatus living in two distinct aquatic habitats were examined for possible variations in their ecology, morphology and behavior. Collections were made seasonally for one year in six Lee Co., Virginia caves, three containing mud-bottom, drip pools and three with small gravel stream habitats. Environmental parameters thought to influence population variation were quantitatively and qualitatively recorded in each of the six caves.

Amphipod densities, body length, female maturity, clutch number and stream washout rates were found to be greater in drip pool habitat populations. Variation was also observed in body coloration and antennal segment-body length …


Improved Techniques For Marking, Night-Viewing, And Aging White-Tailed Deer, Odocoileus Virginianus, Barnard Hodge Powell Apr 1976

Improved Techniques For Marking, Night-Viewing, And Aging White-Tailed Deer, Odocoileus Virginianus, Barnard Hodge Powell

Biological Sciences Theses & Dissertations

These studies were concerned with the development of methods to assist investigators of wildlife population research. Specifically they involve the description of (1) A device which enables an investigator to mark deer at medium range using specially modified darts fired by conventional tranquilizer rifles, (2) Construction of infrared viewers and light sources using surplus equipment and (3) Studies to develop a method of making permanent deer dental impressions under field conditions.


Mammals Of The Bull Run, Edward M. Thatcher Jan 1976

Mammals Of The Bull Run, Edward M. Thatcher

Dissertations and Theses

This study of mammals of the Bull Run Planning Unit has a dual character. First, mammals of special scientific or natural history interest such as threatened or endangered species were sought. This was in conjunction with a Mt. Hood Bull Run Planning Unit. Second, a zoogeographical study of mammals of the Bull Run was performed. Abundance and distributional data was recorded for each species observed. This data was related to availability to moisture as indicated by plant associations trapped. Difference in habitat utilization along a moisture gradient was investigated as a possible coexistence mechanism for sympatric small mammals in the …


Zooplankton Community Dynamics And Water Quality Of Polecat Creek, Coles County, Illinois, Spring, 1975, Carl Edward Baird Jan 1976

Zooplankton Community Dynamics And Water Quality Of Polecat Creek, Coles County, Illinois, Spring, 1975, Carl Edward Baird

Masters Theses

No abstract provided.


Population Dynamics Of Microtus Ochrogaster In Eastern Kansas, Michael S. Gaines, Robert K. Rose Jan 1976

Population Dynamics Of Microtus Ochrogaster In Eastern Kansas, Michael S. Gaines, Robert K. Rose

Biological Sciences Faculty Publications

Four eastern Kansas populations of the prairie vole, Microtus ochrogaster were live trapped from 1970—73 to gain insight into the population regulation of this species. All four populations exhibited a 2—yr cycle in numbers with peak densities generally occurring in June 1972. Peak densities were followed by a decline in numbers, a recovery, and a population crash in spring 1973. Reproductive parameters changed dramatically as density rose and fell. The summer breeding season in the crash year of 1973 was shortened by at least 3 mo. A reduction in breeding activity occurred during the summer of every year of the …


Effect Of Salinity On Glycogen Content In The Brine Shrimp, Artemia Salinas, Of Great Salt Lake, Christon H. Merkley Aug 1975

Effect Of Salinity On Glycogen Content In The Brine Shrimp, Artemia Salinas, Of Great Salt Lake, Christon H. Merkley

Undergraduate Honors Capstone Projects

The brine shrimp, Artemia salinas, is one of the few organisms to be found in the hostile environment of the Great Salt Lake. Salt concentrations in the lake are found to exceed those in the oceans. In such an environment, the utilization of energy, even after it has been procured, presents a problem. The life inhabiting the lake has developed extraordinary adaptations to this and similar problems.

Electron micrographs produced by Dr. Nabil Youssef of Utah State University have revealed that unusual quantities of glycogen can be found in the muscle of brine shrimp taken from the Great Salt Lake. …


Notes On The Natural History Of Plecotus Rafinesquii, Clyde Jones, Royal D. Suttkus Jul 1975

Notes On The Natural History Of Plecotus Rafinesquii, Clyde Jones, Royal D. Suttkus

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

No abstract provided.


Genetic Studies Of Cave And Spring Populations Of The Freshwater Amphipod Crustacean Gammarus Minus Say, Steven Wolf Hetrick Jul 1975

Genetic Studies Of Cave And Spring Populations Of The Freshwater Amphipod Crustacean Gammarus Minus Say, Steven Wolf Hetrick

Biological Sciences Theses & Dissertations

The amphipod Gammaru. minus has three morphotypes in its Appalachian range : (1) a spring form with well-developed eyes, (2) an intermediate cave form with slightly reduced eyes, and (3) an extreme cave form with greatly reduced eyes. This study compares the genetic structure of populations in two karst areas and analyzes the genetics of populations of the three morphotypes.

Genetic data were collected from populations in the Ward's Cove, Virginia and Greenbrier Valley, West Virginia karst areas using zone electrophoresis zymograms. One hundred percent of the Ward's Cove populations are polymorphic at both MDH-1 and PEP 1 loci …


Special Report On Zoo Reform Mar 1975

Special Report On Zoo Reform

Special Reports

The Humane Society of the United States has taken the lead for the past 3 1/2 years in reforming American zoos. HSUS has awakened Americans to the fact that wild animals have been caged inhumanely for many decades in the nation's zoos and that major and drastic actions are necessary to correct these problems. While HSUS has continued to insist that no wild animal should be exploited simply to create an attraction or exhibit, such is not the state of the world as it exists today. Consequently, HSUS is determined to do everything in its power to alleviate the suffering …


Special Report On Controlling America's Pet Population Jan 1975

Special Report On Controlling America's Pet Population

Special Reports

HSUS estimates that public and private animal control programs cost the nation as much as $500 million a year. Much of this expense is required for the feeding and care of unwanted animals during the 5 to 10 days they are held for adoption, killing the 80% that are not adopted or redeemed, and disposing of the carcasses. The result is both an unconscionable waste of life and a needless drain on public and private money.

A large part of the blame for people undertaking pet ownership without having made a total commitment to the animal lies with the pet …


Biological Control Of Insects On The Ord. 1. Production Of Sitotroga Cerealella For Mass Rearing Of Trichogramma Wasps, M Grimm, P. J. T. Lawrence Jan 1975

Biological Control Of Insects On The Ord. 1. Production Of Sitotroga Cerealella For Mass Rearing Of Trichogramma Wasps, M Grimm, P. J. T. Lawrence

Journal of the Department of Agriculture, Western Australia, Series 4

Department of Agriculture entomologists have developed a technique for the production and collection of eggs of the Angoumois grain moth (Sitotroga cerealella) for mass-rearing the parasitic waspTrichogramma pretiosum Riley.

Trichogramma is giving promising results in trials aimed at developing biological control of insect pests in the Ord River Irrigation Area.


Raising Wood Ducks, Richard L. Nelson Jan 1975

Raising Wood Ducks, Richard L. Nelson

Nebraska Game and Parks Commission: Publications

Numbered among Nature's most colorful creatures, wood ducks willingly accept a helping hand from man in establishing new homes. These birds adapt well to suitable habitat, and you can play an important part in bringing the wood duck to locations where they do not now nest. For groups or individuals who are willing to expend the effort necessary to undertake a wood duck restoration project anti see it to completion, it is an exceptional gift from today's generation to those of decades and centuries to come. Many areas in Nebraska provide suitable wood duck habitat, but do not have a …


The Primitive Hunter Culture, Pleistocene Extinction, And The Rise Of Agriculture, Vernon L. Smith Jan 1975

The Primitive Hunter Culture, Pleistocene Extinction, And The Rise Of Agriculture, Vernon L. Smith

Economics Faculty Articles and Research

The hypothesis that megafauna extinction some 10,000 years ago was due to "overkill" by Paleolithic hunters is examined using an economic model of a replenishable resource. The large herding animals that became extinct, such as mammoth, bison, camel, and mastodon, presented low hunting cost and high kill value. The absence of appropriation provided incentives for the wastage killing evident in some kill sites, while the slow growth, long lives, and long maturation of large animals increased their vulnerability to extinction. Free-access hunting is compared with socially optimal hunting and used to interpret the development of conservationist ethics, and controls, in …


A New Species Of Lesser Antillean Typhlops (Serpentes: Typhlopidae), Richard Thomas Jul 1974

A New Species Of Lesser Antillean Typhlops (Serpentes: Typhlopidae), Richard Thomas

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

No abstract provided.


Generic Status Of Opheodrys Mayae, A Colubrid Snake Endemic To The Yucatan Peninsula, Douglas A. Rossman, Gerald C. Shaefer Jul 1974

Generic Status Of Opheodrys Mayae, A Colubrid Snake Endemic To The Yucatan Peninsula, Douglas A. Rossman, Gerald C. Shaefer

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

No abstract provided.


The Ecology Of The Dominant Tick Species In The Northwestern Portion Of The Dismal Swamp National Wildlife Refuge, Mary Keith Garrett Apr 1974

The Ecology Of The Dominant Tick Species In The Northwestern Portion Of The Dismal Swamp National Wildlife Refuge, Mary Keith Garrett

Biological Sciences Theses & Dissertations

Elements of the ecology of the two dominant man-biting ticks were studied during 1971-1973 in two locations in Southeastern Virginia, namely, what is now the Dismal Swamp National Wildlife Refuge and Newport News City Park. Tick species composition, relative abundance, density, and distribution in the two areas were compared. In addition, the Dismal Swamp locality was used as a test area for studies on the survival of native, lab reared and translocated Dermacentor variabilis (Say) and Amblvomma americanum (L.) in relation to selected abiotic factors. The Newport News locality served as a control area for these studies.

The species …


Seasonal Composition Of Zooplankton In The Lafayette River, Norfolk, Virginia, Dahn E. Crandall Apr 1974

Seasonal Composition Of Zooplankton In The Lafayette River, Norfolk, Virginia, Dahn E. Crandall

Biological Sciences Theses & Dissertations

Abstract unavailable.


Mayflies, Or Ephemeroptera, Of West Virginia With Emphasis On The Nymphal Stage, Gerald M. Faulkner Jan 1974

Mayflies, Or Ephemeroptera, Of West Virginia With Emphasis On The Nymphal Stage, Gerald M. Faulkner

Theses, Dissertations and Capstones

This thesis presents the first detailed study of the Ephemeroptera of West Virginia. Eight hundred twelve cites were collected with five hundred eight yielding mayfly specimens. Twelve families are represented including twenty-seven genera and one hundred fifteen species. Four new species are reported along with seventy-seven state records and five hundred twelve county records. Distributional trends of species collected from four or more counties are proposed along with distributional maps on all species reported.


Effects Of Mississippi Delta Flooding On Spider Populations, Peggy Rae Dorris Jan 1974

Effects Of Mississippi Delta Flooding On Spider Populations, Peggy Rae Dorris

Journal of the Arkansas Academy of Science

The Mississippi Delta flooded in the spring of 1973. Spider collections made in a Delta area of Mississippi in 1972 are compared with those made in 1973 during the flood and after it subsided. Because many egg cases and immature and mature spiders were destroyed by the flood, the spider population was diminished.


Threatened Fishes Of Arkansas, Henry W. Robison Jan 1974

Threatened Fishes Of Arkansas, Henry W. Robison

Journal of the Arkansas Academy of Science

Intensive field collecting throughout Arkansas and a survey of literature and museum records revealed 37 fish species and subspecies in Arkansas to be threatened by human activities. Of these 37 threatened forms, seven are considered rare and endangered. One may be extinct. With regard to distribution, 19 threatened forms reside in the White River system and 11 and 10 inhabit the Arkansas and Red River systems, respectively. Nine fishes are considered threatened in the Ouachita River system, four threatened froms are known in the St. Francis drainage, and two are known in the Mississippi River proper.


Nongeographic Variation In The Long-Nosed Bat, Choeroniscus Intermedius, Hugh H. Genoways, Robert J. Baker, Bernard Wyatt Aug 1973

Nongeographic Variation In The Long-Nosed Bat, Choeroniscus Intermedius, Hugh H. Genoways, Robert J. Baker, Bernard Wyatt

University of Nebraska State Museum: Mammalogy Papers

Of the 12 measurements analyzed, only length of tail exhibited enough individual variation to warrant its deletion in analysis of geographic or interspecific variation in the genus Choeroniscus. Also, because of the difficulty in consistently taking the measurement, we also suggest elimination of postorbital constriction.

Specimens of Choeroniscus intermedius were found to exhibit significant secondary sexual variation in five of the 12 measurements studied. Therefore, it is clear that males and females should be separated in analyses of variation within members of the genus. Females were found to be the larger in 10 of the 12 measurements--similar to the …


A Simulation Model Of Peromyscus Leucopus In An Area Of The Great Dismal Swamp, James E. Paschal Jr. Jul 1973

A Simulation Model Of Peromyscus Leucopus In An Area Of The Great Dismal Swamp, James E. Paschal Jr.

Biological Sciences Theses & Dissertations

A computer simulation model was developed to explain the population dynamics of the white-footed mouse (Peromyscus leucopus) in an area of the Great Dismal Swamp. The model was designed to provide an experimental base for future studies. The model indicates relationships between food availability, home range size, competition with Peromyscus nuttali habitat selection and reproduction.

White-footed mice were trapped in the Old Dismal Town site during each season from April, 1972 through March, 1973. The age-sex structure of the population was determined, and was compared with the simulated structure. Although there were significant discrepancies between the comparisons, the …


The Bobwhite Quail, Norm Dey, Jack Sinn Jan 1973

The Bobwhite Quail, Norm Dey, Jack Sinn

Nebraska Game and Parks Commission: Publications

A Year with the Bobwhite

Population Dynamics—Managing the Variables

The Way to Quail Abundance


The Ring-Necked Pheasant In Nebraska, William L. Baxter, Carl W. Wolfe Jan 1973

The Ring-Necked Pheasant In Nebraska, William L. Baxter, Carl W. Wolfe

Nebraska Game and Parks Commission: Publications

Ringneck—Its Past and Prospects: A most successful exotic, pheasant numbers are declining

Nuptial Rites and Nesting: Spring recoups winter’s losses

Summer Broods: While cocks undergo their annual moult, hens enter the brooding period; for eight weeks, hens attend chicks

Hunting the Ring-necked Pheasant

Season of Testing: Nebraska’s winters test a pheasant’s mettle, but given good cover and an adequate food supply, the ringneck is almost impervious to the elements

Methods of Management


Life History And Ecology Of The Ring-Necked Pheasant In Nebraska, William L. Baxter, Carl W. Wolfe Jan 1973

Life History And Ecology Of The Ring-Necked Pheasant In Nebraska, William L. Baxter, Carl W. Wolfe

Nebraska Game and Parks Commission: Publications

Table of Contents

The Study … 6

Population Studies … 8 ...

Methods … 8 ...

Results and Discussion … 9

Nesting Studies … 13 ...

Methods … 13 ...

Results and Discussion … 14 ...

Nest Parasitism … 16 ...

Effects of Nest Searching on Nest Fate ... 17 ...

Nesting Chronology ... 18 ...

Roadside Nests ... 21 ...

Nesting in Experimental Alfalfa ... 22 ...

Pheasant Production in Wetlands ... 23

Brood Studies … 26 ...

Methods ... 26 ...

Sampling Problems ... 26 ...

Results and Discussion ... 27

Cover Utilization by Pheasant Broods ... 29 …