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Ecology and Evolutionary Biology

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Articles 17971 - 18000 of 19673

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Disturbed Alpine Ecosystems: Seedling Establishment Of Early And Late Seral Dominant Species, Jeanne C. Chambers May 1987

Disturbed Alpine Ecosystems: Seedling Establishment Of Early And Late Seral Dominant Species, Jeanne C. Chambers

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This study examined the effects of seedbed and seedling environment on establishment of early and late seral dominant alpine species. Species studied included late seral dominant forbs (Geum rossii, Artemisia scopulorum, and Polemonium viscosum), early seral dominant forbs (Potentilla diversifolia and Sibbaldia procumbens), a late seral dominant grass (Festuca idahoensis), and early seral dominant grasses (Calamagrostis purpurascens and Deschampsia cespitosa). Germination responses of each species to wet vs. dry cold stratification and light vs. dark conditions were investigated. No statistical differences were observed in the seed germination of early and late …


Autecological And Grazing Control Studies Of Dyers Woad (Isatis Tinctoria L.) On Northern Utah Rangelands, Kassim O. Farah May 1987

Autecological And Grazing Control Studies Of Dyers Woad (Isatis Tinctoria L.) On Northern Utah Rangelands, Kassim O. Farah

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Dyers woad (Isatis tinctoria L.) is a noxious weed on northern Utah rangelands. Chemical and mechanical means of control are unsuitable for rangelands. A potential alternative, biological control, is difficult due to a lack of basic ecological information. To remedy this, some aspects of the population biology and autecolgy of dyers woad were studied. The feasibility of controlling dyers woad by early spring grazing was also investigated via clipping experiments.

A population study followed the survivorship of experimentally established populations over two years. Fall germinating individuals (1984) overwintered as rosettes twice and all survivors reproduced successfully. Spring germinating individuals …


Causes Of Seeding Failure Within The Tooele Fire Rehabilitation Project In Northwestern Utah, Jeffrey S. Murphy May 1987

Causes Of Seeding Failure Within The Tooele Fire Rehabilitation Project In Northwestern Utah, Jeffrey S. Murphy

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The original purpose of this study was to examine the influences of ecological site, seeding method and planting season on rangeland seeding success within the Tooele Fire Rehabilitation Project (TFRP) in northwestern Utah. The major objective of the TFRP, designed by the USDI Bureau of Land Management, was to establish a permanent cover of 'Nordan' crested wheatgrass (Aqropyron desertorum (Fischer ex Link) Schultes), 'Luna' pubescent wheat grass (Thinopyrum intermedium ssp. barbulatum (Schur) Barkw. and D. R. Dewey) and 'Alkar' tall wheatqrass (Thinopyrum ponticum (Podp.) Barkw. and D. R. Dewey) on approximately 20,000 ha of rangeland burned by a wildfire in …


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 …


Attraction To Blood As A Factor In Tail-Biting By Pigs, David Fraser Apr 1987

Attraction To Blood As A Factor In Tail-Biting By Pigs, David Fraser

Abnormal Behavior Collection

Canvas models, about the size of a pig's tail, were impregnated with pigs' blood or left plain, and were presented to pigs for 12 days in a 2-choice preference test. The pigs showed large, consistent, individual differences in response: some pigs chewed the models continuously while others chewed only slightly; some chewed much more on the blood-covered model, while others showed no preference. On average, the pigs chewed considerably more on the blood-covered model than on the plain one. In a second experiment, pigs presented with a choice test involving a blood-covered and a plain model showed a significant increase …


Short Term Temporal And Spatial Variability Of Phytoplankton In The Elizabeth River, Robert L. O'Reilly Apr 1987

Short Term Temporal And Spatial Variability Of Phytoplankton In The Elizabeth River, Robert L. O'Reilly

Biological Sciences Theses & Dissertations

This study was designed to evaluate short-term temporal and spatial components of phytoplankton variability within a tidal estuarine system, in reference to natural changes in the local environment.

Multiple water samples were collected weekly from October to December 1984 at 4 stations in different branches, or sections, of the Elizabeth River. Collection of chlorophyll~ data was structured to fit an analysis of variance, while the phytoplankton species and their environmental relationships were analyzed using multivariate techniques.

Lower chlorophyll a concentrations from 0.75 to 2.87 ug/1 were characteristic of the Main Stem and Southern Branch, while higher values of 1.27 …


Evaluation Of Two Methods For Estimating Belowground Production In The Great Dismal Swamp, Millie Symbula Apr 1987

Evaluation Of Two Methods For Estimating Belowground Production In The Great Dismal Swamp, Millie Symbula

Biological Sciences Theses & Dissertations

Two methods were used to estimate belowground production in a maple-gum stand in the seasonally flooded Great Dismal Swamp of Virginia. The first was an auger method which involved sequential core sampling. The second method was an implanted soil mass technique. Nylon mesh bags were filled with peat and buried at the study site. New growth into these implants was taken to be production.

Mean annual lateral root biomass and necromass to 40 cm, determined from soil cores, were 583 g·m-2 and 281 g·m-2, respectively. Production estimates for roots ≤ 5 mm in diameter, using soil cores, …


Effect Of Changes In Regional Forest Abundance On The Decline And Recovery Of A Forest Bird Community, Robert A. Askins, Margarett J. Philbrick Mar 1987

Effect Of Changes In Regional Forest Abundance On The Decline And Recovery Of A Forest Bird Community, Robert A. Askins, Margarett J. Philbrick

Biology Faculty Publications

Bird populations were monitored for 32 years in a 23-ha tract of hemlock-hardwood forest. Between 1953 and 1976 the total abundance of long-distance migrants declined significantly and four species disappeared, but after 1976 both the total abundance and the number of species increased. Multiple regression analysis shows that the abundance of long-distance migrants was negatively related to abundance of bird species characteristic of suburban habitats and positively related to the amount of forest within 2 km of the study area. The decline in long-distance migrants before 1976 occurred when suburban species were increasing and nearby forest was destroyed. The increase …


Book Review Of Evolution As Religion, Carl J. Bajema Mar 1987

Book Review Of Evolution As Religion, Carl J. Bajema

Other Scholarly Publications

No abstract provided.


The Prairie Naturalist Volume 19, No. 1 March 1987 Mar 1987

The Prairie Naturalist Volume 19, No. 1 March 1987

The Prairie Naturalist

Paul B. Kannowski, Editor

Nikki R. Seabloom, Assistant Editor

Douglas H. Johnson, Book Review Editor

TABLE OF CONTENTS

ECOLOGY OF WHITE-TAILED DEER IN UPLAND PONDEROSA PINE HABITAT IN SOUTHEASTERN MONTANA ▪ G. L. Dusek

PRECISION AND BIAS OF A SUMMER AERIAL TRANSECT CENSUS OF PRONGHORN ANTELOPE ▪ S. H. Allen and J. M. Samuelson

ACTIVITY PATTERNS, MOVEMENTS, AND HOME RANGES OF PRAIRIE MINK ▪ T. W. Arnold and E. K. Fritzell

BRYOPHYTES OF THE SOUTH UNIT OF THEODORE ROOSEVELT NATIONAL PARK, NORTH DAKOTA ▪ C. L. Blaney and D. H. Norris

FALL FOOD HABITS OF WILD TURKEYS IN SOUTH CENTRAL …


Maine Acid Rain Study : Reports, Maine Department Of Environmental Protection Feb 1987

Maine Acid Rain Study : Reports, Maine Department Of Environmental Protection

Maine Collection

Maine Acid Rain Study : Reports

Maine Department of Environmental Protection, Augusta, Maine (February, 1987).

Contents: Acid Rain Precursor Inventory and Evaluation / Modeled Sulfur Deposition in Maine / High Elevation Lake Monitoring in Maine


Western Rock Lobster Industry Compensation Study. Report To The Rock Lobster Industry Advisory Committee By Arthur Young Services., Arthur Young Services Feb 1987

Western Rock Lobster Industry Compensation Study. Report To The Rock Lobster Industry Advisory Committee By Arthur Young Services., Arthur Young Services

Fisheries Management Papers

Terms of reference are outlined in letter dated 11 August 1986. The Fisheries Department seeks to reduce western rock lobster fishing capacity to ensure the long-term viability of the fishery and has asked us to evaluate the financial implications of a number of specific resource management proposals.


Residual Pesticides In Fishes From Lake Chicot, Arkansas, C. M. Cooper, S. S. Knight Jan 1987

Residual Pesticides In Fishes From Lake Chicot, Arkansas, C. M. Cooper, S. S. Knight

Journal of the Arkansas Academy of Science

Samples of fish from isolated and flow-through portions of Lake Chicot, Arkansas, were analyzed for residual pesticide concentrations from 1978 and 1981. Where appropriate ecologically, fish flesh, viscera and whole fish, were analyzed for the common organochlorine insecticides DDT [1,1 ,1-trichloro -2,2bis(p-chlorophenyl)-ethane], DDE [1,1-dichloro-2,2-bis(p-chlorophenyl)-ethyene], DDD [1,1-dichloro -2,2-bis(p-chlorophenyl)-ethane], toxaphene (chlorinated camphene), chlordane, heptachlor, heptachlor epoxide, dieldrin, and endrin. DDT, DDT metabolites, and heptachlor were significantly (a = 0.05) higher in spotted gar (Lepisosteus oculatus) and yellow bullhead catfish (Ictalurus natalis) than in other species examined. Pesticide concentrations did not exceed the acceptable levels established by the U.S. Environmental Protection Agency although …


Selected Families Of Trichoptera In Arkansas, Veryl V. Board Jan 1987

Selected Families Of Trichoptera In Arkansas, Veryl V. Board

Journal of the Arkansas Academy of Science

No abstract provided.


Greater Yellowstone Ecosystem, U.S. House Committee On Insular Affairs Jan 1987

Greater Yellowstone Ecosystem, U.S. House Committee On Insular Affairs

All U.S. Government Documents (Utah Regional Depository)

No abstract provided.


Report Of The Rock Lobster Industry Advisory Committee Meeting Of 27 January 1987 - Report By The Chairman Mr. B.K. Bowen., B. K. Bowen Jan 1987

Report Of The Rock Lobster Industry Advisory Committee Meeting Of 27 January 1987 - Report By The Chairman Mr. B.K. Bowen., B. K. Bowen

Fisheries Management Papers

The Rock Lobster Industry Advisory Committee met in Perth on Tuesday 17 January 1987. Committee discussed the following: Policy on 5% pot loss on replacement of vessels less than six years old. Study of industry funded compensation mechanism for fishing capacity reductions. 20 Fathom rule. Future maintenance of the zone E boundary. The recreational Rock Lobster Fishery. Rock Lobster pot distribution. Options for a 10 per cent reduction in fishing effort. 1987 coastal tour. Augusta-Windy Harbour Rock Lobster Working Group. Report on the 1986/87 season.


An Inventory And Condition Survey Of Rangelands In The Carnarvon Basin, Western Australia, A L. Payne, G F. Spencer, P J. Curry Jan 1987

An Inventory And Condition Survey Of Rangelands In The Carnarvon Basin, Western Australia, A L. Payne, G F. Spencer, P J. Curry

Technical Bulletins

The inventory and condition survey of rangelands in the Carnarvon Basin, undertaken by the Department of Agriculture and Food, Western Australia (DAFWA) between 1980 and 1982, describes and maps the natural resources of the region’s pastoral leasehold land. This survey report provides a baseline record of the existence and condition of the natural area’s resources, to assist with the planning and implementation of land management practices. The report identified and described the condition of soils, landforms, vegetation, habitat, ecosystems, and declared plants and animals. It also assessed the impact of pastoralism and made land management recommendations. The area surveyed covers …


Specimen Catalog, Joseph A. Cook Jan 1987

Specimen Catalog, Joseph A. Cook

Division of Mammals - Field Notes and Catalogs

No abstract provided.


Dimilin For Control Of Lernaea In Golden Shiner Ponds, Gary Burtle, John Morrison Jan 1987

Dimilin For Control Of Lernaea In Golden Shiner Ponds, Gary Burtle, John Morrison

Journal of the Arkansas Academy of Science

A single application of Oimilin (UNIROYAL),diflubenzuron, was tested in 9 (nine) ponds containing golden shiner minnows, Notemigonus crysoleucas, infested with the parasitic copepod Lernaea cyprinacea. The chemical was applied at a rate of1 0 or 30 pg/l and compared to untreated controls. Fish were periodically sampled to determine levels of infestation, and zooplankton numbers were monitored for chemical effect. Oimilin treatment significantly reduced (P < 0.05) parasite infestation four to eight days after treatment. No significant difference (P < 0.05) was noted between the two levels of treatment. Zooplankton populations decreased in the Dimilin treated ponds following chemical application. Rotifer populations rebounded later during the period, but copepod populations in the ponds treated with 30 ng/L remained depressed from two days after treatment for one month until the study ended. Complete parasite control was not obtained with either chemical concentration using a single application. These results suggest that a single treatment is not effective for Lernaea control. Future research will test two applications 10 days apart at the 10 and 30 /xg/L levels.


Some Potential Evolutionary Costs Associated With Paternal Care In The Water Bug Belostoma Flumineum Say, Larry Johnson Jan 1987

Some Potential Evolutionary Costs Associated With Paternal Care In The Water Bug Belostoma Flumineum Say, Larry Johnson

Masters Theses

Female water bugs (Belostoma flumineum) deposit eggs in a mucilaginous cement on the back of conspecific males, who then brood these eggs until hatching. Sex role reversal, in which females compete for males and males are discriminating, is predicted in this species because males provide parental care exclusively, and represent a limited resource. Presumably the advantage of this paternal behavior is increased survival of young. However, the potential exists for this egg-brooding behavior to incur evolutionary costs, and quantifying some of these costs was the thrust of this study.

One cost, a loss of polygynous opportunity, was investigated …


Characteristics Of Successful Competitors: An Evaluation Of Potential Growth Rate In Two Cold Desert Tussock Grasses, Eissenstat D. M., Caldwell M. M. Jan 1987

Characteristics Of Successful Competitors: An Evaluation Of Potential Growth Rate In Two Cold Desert Tussock Grasses, Eissenstat D. M., Caldwell M. M.

Aspen Bibliography

Within the first few weeks after seedling emergence, Agropyron desertorum, a more competitive tussock grass, had a much higher mean relative growth rate (RGR) than Agropyron spicatum, a very similar, but less competitive species. However, beyond the early seedling stage, the two grasses had a remarkably similar whole-plant RGR in hydroponic culture and aboveground RGR in glasshouse soil, if root temperatures were above approximately 12° C. At soil temperatures between 5 and 12° C, A. desertorum exhibited a 66% greater aboveground RGR than A. spicatum (P < 0.05). Both species responded similarly to warming soil temperatures. In the field, however, tiller growth rates were generally similar. Neither species showed marked tiller elongation until a couple of weeks after snowmelt, by which time soil temperatures, at least to a depth of 10 cm, were above 12° C for a significant portion of the day. Above-ground biomass accumulation over a three-year period indicated that both grasses had similar potential growth rates whereas Artemisia tridentata ssp. vaseyana, a common neighbor planted in the same plots, had a much greater potential growth rate. The greater competitive ability of adult A. desertorum, as compared to A. spicatum, cannot be attributed to appreciable differences in potential growth rates.


Hyla Versicolor-Chrysoscelis Species Complex Of Gray Treefrogs In Arkansas: Histological And Ultrastructural Evidence, Phyllis Chaffin, Stanley E. Trauth Jan 1987

Hyla Versicolor-Chrysoscelis Species Complex Of Gray Treefrogs In Arkansas: Histological And Ultrastructural Evidence, Phyllis Chaffin, Stanley E. Trauth

Journal of the Arkansas Academy of Science

We investigated the Hyla versicolor-chrysoscelis species complex (tetraploid and diploid species, respectively) of cryptic gray treefrogs from Arkansas using light and scanning electron microscopy. From previous studies of this treefrog complex in other states, H. versicolor has been shown to exhibit larger nuclear diameters and larger toe pad epithelial cells than H. chrysoscelis. Based upon average nuclear diameters of eyelid epithelial cells, we found two or possibly three groups of frogs. The presumed H. versicolor exhibited greatly enlarged toe pad epithelial cells using scanning electron microscopy and were found in four counties, three of which are in the Ozark Mountains. …


Clinostomum Marginatum Metacercaria: Incidence In Smallmouth Bass From A North Arkansas Stream And In Vitro Oxygen Consumption Studies, James J. Daly, Howard H. Conaway, Terryl L. Hostetler, H. Michael Matthews Jan 1987

Clinostomum Marginatum Metacercaria: Incidence In Smallmouth Bass From A North Arkansas Stream And In Vitro Oxygen Consumption Studies, James J. Daly, Howard H. Conaway, Terryl L. Hostetler, H. Michael Matthews

Journal of the Arkansas Academy of Science

Small mouth bass (Micropterus dolomieui) captured from Crooked Creek (Marion Co., Arkansas) in the summers of 1977 and 1987 were found to have a high incidence of infection with the metacercaria of Clinostomum marginatum (yellow grub). Of 41 fish collected in 1977, 32 (78%) were found infected with metacercariae with some fish containing large numbers of parasites. The number of larvae per fish ranged from 1 to 184, with an average of 23.2 ± 38 per smallmouth. Eighty-six percent of the bass collected in 1987 were found positive for C. marginatum. The number of metacercariae per fish ranged from 1 …


Distribution Of Fish Within Headwater Riffles Of The Illinois River System, Washington County, Arkansas, Danny J. Ebert, Arthur V. Brown, Carolyn B. Fielder Jan 1987

Distribution Of Fish Within Headwater Riffles Of The Illinois River System, Washington County, Arkansas, Danny J. Ebert, Arthur V. Brown, Carolyn B. Fielder

Journal of the Arkansas Academy of Science

Quantitative sampling of fish was performed in five headwater riffles of the Illinois River System, Washington County, Arkansas during low flow conditions. This study revealed differing fish species composition, biomass and feeding guild segregation between head and tail riffle reaches in 1st through 3rd order. Thirty species representing 10 families were identified. Of this number, darters (Percidae), sculpins (Cottidae), madtoms (Ictaluridae), and central stonerollers (Campostoma anomalum) (Cyprinidae) comprised 67 to 98 percent of riffle head populations. Fish biomass was greater for riffle head areas (0.58-6.6/0.28-2.0 g/m2 ) within sectivores and herbivores dominating. Total fish numbers decreased from riffleheads to tails, …


Distribution And Status Of Rare And Endangered Mussels (Mollusca: Margaritiferidae, Unionidae) In Arkansas, John L. Harris, Mark E. Gordon Jan 1987

Distribution And Status Of Rare And Endangered Mussels (Mollusca: Margaritiferidae, Unionidae) In Arkansas, John L. Harris, Mark E. Gordon

Journal of the Arkansas Academy of Science

Knowledge of the distribution and population status of freshwater bivalves occurring in Arkansas has increased markedly during the past decade. Sufficient data has become available to delineate species which are rare and/or endangered within the state. Historical and recent records from Arkansas exist for four mussels currently listed as federally endangered species: the fat pocketbook (Potamilus capax), the pink mucket (Lampsilis orbiculata), Curtis' pearly mussel (Epioblasma florentina curtisi), and the turgid-blossom pearly mussel (Epioblasma turgidula). Ten additional mussels which occur or were thought to occur in Arkansas are being considered for federal protection by the United States Fish and Wildlife …


Distribution Of Fishes In Reference Streams Within Arkansas' Ecoregions, William E. Keith Jan 1987

Distribution Of Fishes In Reference Streams Within Arkansas' Ecoregions, William E. Keith

Journal of the Arkansas Academy of Science

The State of Arkansas has been subdivided into six ecoregions based on the homogeneity of land surface forms, potential natural vegetation, soil types and land uses. Reference streams of various sizes, excluding the large rivers, and with the least amount of point source and non-point source disturbances were selected for intensive physical, chemical and biological sampling. These data are to be used to characterize the streams and establish water quality criteria which will protect all stream uses. Fish communities of the reference streams were distinctively different among the ecoregions and can easily be used to characterize the waters of different …


Status Of The Instream Flow Issue In Arkansas, 1987, Stephen P. Filipek, William E. Keith, John Giese Jan 1987

Status Of The Instream Flow Issue In Arkansas, 1987, Stephen P. Filipek, William E. Keith, John Giese

Journal of the Arkansas Academy of Science

Expansion of Arkansas' population with concurrent increases in the state's domestic, industrial, and agricultural water uses and possible out-of-state diversion are placing substantial demands on the state's water resources. In an attempt to address this growing concern, Act 1051 (1985) of the Arkansas legislature was passed requiring the determination of present and future state water needs. A specific area of this mandate was the quantification of instream flow requirements. Basic instream flow needs are maintenance of the aquatic ecosystem and dependent riparian environment. Flow reservation may compliment other instream uses such as recreation, navigation, water quality, and groundwater recharge. However, …


Effect Of City Effluent On The Diversity Of Aquatic Macroinvertabrates Of Sugar Creek, Clay County, Arkansas, Kay Cargill, George L. Harp Jan 1987

Effect Of City Effluent On The Diversity Of Aquatic Macroinvertabrates Of Sugar Creek, Clay County, Arkansas, Kay Cargill, George L. Harp

Journal of the Arkansas Academy of Science

No abstract provided.


Rediscovery Of The Suckermouth Minnow, Phenacobius Mirabilis (Girard), In Arkansas, William E. Keith, Thomas M. Buchanan, Henry W. Robison Jan 1987

Rediscovery Of The Suckermouth Minnow, Phenacobius Mirabilis (Girard), In Arkansas, William E. Keith, Thomas M. Buchanan, Henry W. Robison

Journal of the Arkansas Academy of Science

No abstract provided.


The Identification Of The Threatened Southeastern Shrew Using Multivariate Statistical Techniques, Thomas M. Padgett, Roger K. Everton, Robert K. Rose Jan 1987

The Identification Of The Threatened Southeastern Shrew Using Multivariate Statistical Techniques, Thomas M. Padgett, Roger K. Everton, Robert K. Rose

Biological Sciences Faculty Publications

The threatened subspecies of the southeastern shrew, Sorex longirostris fisheri, is endemic to the Great Dismal Swamp of southeastern Virginia. Previous studies based on discriminant analysis of external measurements determined that intergrades with the upland form, Sorex l. longirostris, exist along the periphery of the Swamp. To better discriminate among these populations, a study of cranial morphology was initiated. Fifteen cranial measurements were taken, using 59 specimens of Sorex collected previously form southeastern Virginia, including the Dismal Swamp. Both Principal Component and Cluster Analyses revealed no significant cranial variation or morphometric patterns within the specimens examined, but a …