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Monitoring Results For Pfiesteria Piscidida And Pfiesteria-Like Organisms From Virginia Waters In 1998, Harold G. Marshall, David W. Seaborn, Jennifer Wolny Jan 1999

Monitoring Results For Pfiesteria Piscidida And Pfiesteria-Like Organisms From Virginia Waters In 1998, Harold G. Marshall, David W. Seaborn, Jennifer Wolny

Biological Sciences Faculty Publications

Results of an extensive 1998 monitoring program for the presence of Pfiesteria-like organisms (PLO) in Virginia estuaries indicate these dinoflagellates are widely distributed in both the water column, and as cysts in the sediment, however Pfiesteria piscicida was not detected at this time. The highest concentrations of PLO were in estuaries along the Virginia shore line of the Potomac River, and in western Chesapeake Bay estuaries from the Little Wicomico River to the Rappahannock River. The most common PLO included Cryptoperidiniopsis sp. and Gymnodinium galatheanum. The lowest PLO concentrations were at ocean side locations. PLO were also …


Alpha Status, Dominance, And Division Of Labor In Wolf Packs, L. David Mech Jan 1999

Alpha Status, Dominance, And Division Of Labor In Wolf Packs, L. David Mech

United States Geological Survey, Northern Prairie Wildlife Research Center: Publications

The prevailing view of a wolf (Canis lupus) pack is that of a group of individuals ever vying for dominance but held in check by the “alpha” pair, the alpha male and alpha female. Most research on the social dynamics of wolf packs, however, has been conducted on non-natural assortments of captive wolves. Here I describe the wolf-pack social order as it occurs in nature, discuss the alpha concept and social dominance and submission, and present data on the precise relationships among members in free-living packs, based on a literature review and 13 summers of observations of wolves …


Twenty-Year Home-Range Dynamics Of A White-Tailed Deer Matriline, Michael E. Nelson, L. D. Mech Jan 1999

Twenty-Year Home-Range Dynamics Of A White-Tailed Deer Matriline, Michael E. Nelson, L. D. Mech

United States Geological Survey, Northern Prairie Wildlife Research Center: Publications

We examined the seasonal migration and home-range dynamics of a multigeneration white-tailed deer (Odocoileus virginianus) matriline comprising six females from four generations spanning a 20-year period in northeastern Minnesota. All, from the matriarch to her great-granddaughter, migrated to the same summer and winter ranges, the longest individual record being 14.5 years. Three maternal females concurrently occupied exclusive fawning sites within their ancestral matriarch’s summer range, while two nonmaternal females explored new areas and ranged near their mothers. One great-granddaughter expanded her summer range 1 km beyond the matriarch’s summer range while essentially vacating half of her ancestors’ range …


The Effect Of Proximity On Landmark Use In Clark’S Nutcrackers, Kristy L. Gould-Beierle, Alan Kamil Jan 1999

The Effect Of Proximity On Landmark Use In Clark’S Nutcrackers, Kristy L. Gould-Beierle, Alan Kamil

Avian Cognition Papers

Clark’s nutcrackers, Nucifraga columbiana, store thousands of pine seeds during the autumn and retrieve them throughout the winter. It has been shown that these birds are able to use visual cues to relocate hidden food in the laboratory. In this set of experiments, we trained three groups of Clark’s nutcrackers to find a hidden food goal that was placed in the same spatial location relative to the testing room. During training, the location of two local cues in relation to the goal differed between the three groups. Group 1 learned the task with the cues closest to the goal, group …


Patterns Of Movement And Orientation During Caching And Recovery By Clark’S Nutcrackers, Nucifraga Columbiana, Alan Kamil, Russell P. Balda, Sally Good Jan 1999

Patterns Of Movement And Orientation During Caching And Recovery By Clark’S Nutcrackers, Nucifraga Columbiana, Alan Kamil, Russell P. Balda, Sally Good

Avian Cognition Papers

Clark’s nutcrackers regularly store large numbers of pine seeds and remember the locations of the cached seeds. Although they are very accurate, they do make some errors during recovery. In an attempt to determine whether any behaviours during caching predicted the occurrence of errors during recovery, we videotaped Clark’s nutcrackers while they cached and recovered seeds under laboratory conditions. We used the videotapes to develop complete, quantitative descriptions of caching and recovery behaviour, with an emphasis on body orientation and directions of movement. During caching, the birds showed the greatest change in their orientation and direction following cache creation. During …


Searching Image In Blue Jays: Facilitation And Interference In Sequential Priming, Alan B. Bond, Alan C. Kamil Jan 1999

Searching Image In Blue Jays: Facilitation And Interference In Sequential Priming, Alan B. Bond, Alan C. Kamil

Papers in Behavior in Biological Sciences

Repeated exposure to a single target type (sequential priming) during visual search for multiple cryptic targets commonly improves performance on subsequent presentations of that target. It appears to be an attentional phenomenon, a component of the searching image effect. It has been argued, however, that if searching image is an attentional process, sequential priming should also interfere with performance on subsequent nonprimed targets, and such interference has never been unequivocally demonstrated. In blue jays (Cyanocitta cristata) searching in an operant apparatus for targets derived from images of cryptic moths, detection performance was strongly facilitated in the course of …


How Do They, Indeed? A Reply To Biegler Et Al., Alan Kamil, Juli E. Jones Jan 1999

How Do They, Indeed? A Reply To Biegler Et Al., Alan Kamil, Juli E. Jones

Avian Cognition Papers

We trained Clark’s nutcrackers, Nucifraga columbiana, to search halfway between two landmarks while varying the distance between the landmarks (Kamil & Jones 1997). We found that the birds learned the problem readily and generalized to novel interlandmark distances within the range of distances used during training. Unlike some other studies in which responses to proportional distance were obtained (e.g. O’Keefe & Burgess 1996; Tommasi et al. 1997), the nutcrackers showed very precise search and maintained this precision during the transfer test. The distributions of digging locations around the central position were concentrated within ±1–2 cm of the central location …


A Method For Estimating Marine Habitat Values Based On Fish Guilds, With Comparisons Between Sites In The Southern California Bight, Alan B. Bond, John S. Stephens, Jr., Daniel J. Pondella, Ii, M. James Allen, Mark Helvey Jan 1999

A Method For Estimating Marine Habitat Values Based On Fish Guilds, With Comparisons Between Sites In The Southern California Bight, Alan B. Bond, John S. Stephens, Jr., Daniel J. Pondella, Ii, M. James Allen, Mark Helvey

Papers in Behavior in Biological Sciences

Habitat valuation is an essential tool for tracking changes in habitat quality and in adjudicating environmental mitigation. All current methods for estimating habitat values of coastal marine sites rely heavily on the opinion of experts or on data variables that can readily be manipulated to influence the outcome. As a result, unbiased, quantitative comparisons between the values of different marine habitats are generally unavailable. We report here on a robust, objective technique for the valuation of marine habitats that makes use of data that are commonly gathered in surveys of marine fish populations: density, fidelity, and mean size. To insure …


Female Responses To Isolated Signals From Multimodal Male Courtship Displays In The Wolf Spider Genus Schizocosa (Araneae: Lycosidae), Eileen Hebets, George W. Uetz Jan 1999

Female Responses To Isolated Signals From Multimodal Male Courtship Displays In The Wolf Spider Genus Schizocosa (Araneae: Lycosidae), Eileen Hebets, George W. Uetz

Eileen Hebets Publications

Male wolf spiders within the genus Schizocosa display considerable variation in foreleg ornamentation as well as in courtship communication. Multiple modes of male signaling have evolved in a number of species. Divergence in courtship signals among species within this genus may be directly associated with variation in the sensory sensitivities of conspecific females. We isolated the visual and vibratory courtship cues of four species of Schizocosa and recorded conspecific female receptivity to each isolated cue. We also examined female receptivity to complete multimodal courtship signals. We found that the sensory sensitivities of conspecific females were associated with the predominant modes …


Plant Hybrid Zones And Insect Host Range Expansion, Diana Pilson Jan 1999

Plant Hybrid Zones And Insect Host Range Expansion, Diana Pilson

Diana Pilson Publications

The hybrid bridge hypothesis suggests that plant hybrids ‘‘bridge’’ the genetic gap between actual and potential host species, and that, for this reason, herbivorous insects are more likely to evolve an expanded host range in the presence of hybrids. While intuitively appealing, the hypothesis has two implicit assumptions: that phenotypic gaps between potential hosts limit host range, and that characters controlling host use are additively inherited in plant hybrids. Evaluation of these assumptions suggests that operation of the hybrid bridge hypothesis is relatively uncommon. In addition, the hypothesis has not been well integrated into existing theoretical and empirical work on …


Sociality And Social Learning In Two Species Of Corvids: The Pinyon Jay (Gymnorhinus Cyanocephalus) And The Clark’S Nutcracker (Nucifraga Columbiana), Jennifer J. Templeton, Alan Kamil, Russell P. Balda Jan 1999

Sociality And Social Learning In Two Species Of Corvids: The Pinyon Jay (Gymnorhinus Cyanocephalus) And The Clark’S Nutcracker (Nucifraga Columbiana), Jennifer J. Templeton, Alan Kamil, Russell P. Balda

Papers in Behavior in Biological Sciences

The hypothesis that social learning is an adaptive specialization for social living predicts that social species should learn better socially than they do individually, but that nonsocial species should not exhibit a similar enhancement of performance under social learning conditions. The authors compared individual and social learning abilities in 2 corvid species: the highly social pinyon jay (Gymnorhinus cyanocephalus) and the less social Clark’s nutcracker (Nucifraga columbiana). The birds were tested on 2 different tasks under individual and social learning conditions. Half learned a motor task individually and a discrimination task socially; the other half learned …


Evolutionary Relationships Among The Protostrongylidae (Nematoda: Metastrongyloidea) As Inferred From Morphological Characters, With Consideration Of Parasite-Host Coevolution, Ramon A. Carreno, Eric P. Hoberg Jan 1999

Evolutionary Relationships Among The Protostrongylidae (Nematoda: Metastrongyloidea) As Inferred From Morphological Characters, With Consideration Of Parasite-Host Coevolution, Ramon A. Carreno, Eric P. Hoberg

Harold W. Manter Laboratory of Parasitology: Faculty Publications

The phylogeny of nematodes in the family Protostrongylidae (Nematoda: Metastrongyloidea) was reconstructed by cladistic analysis of 28 binary and multistate characters derived from comparative morphology. Analyses were hierarchical, and examined (1) relationships among genera, including 13 ingroup taxa and Metastrongylidae as an outgroup (single tree, 78 steps, consistency index [CI]=0.705); and (2) relationships among genera and species groups including 21 ingroup taxa and Metastrongylus apri as an outgroup (single tree, 76 steps, CI=0.582). In the species-level tree, Protostrongylidae was divided into 2 major clades, one containing the subfamilies Muelleriinae (including the recently described Umingmakstrongylus pallikuukensis) Elaphostrongylinae, and the Varestrongylinae …


Experimental Infections Of Muskoxen (Ovibos Moschatus) And Domestic Sheep With Umingmakstrongylus Pallikuukensis (Nematoda: Protostrongylidae): Parasite Development, Population Structure, And Pathology, Susan J. Kutz, Eric P. Hoberg, Lydden Polley Jan 1999

Experimental Infections Of Muskoxen (Ovibos Moschatus) And Domestic Sheep With Umingmakstrongylus Pallikuukensis (Nematoda: Protostrongylidae): Parasite Development, Population Structure, And Pathology, Susan J. Kutz, Eric P. Hoberg, Lydden Polley

Harold W. Manter Laboratory of Parasitology: Faculty Publications

Three captive muskoxen (Ovibos moschatus) were successfully infected with third-stage larvae of Umingmakstrongylus pallikuukensis digested or emerged from the slugs Deroceras reticulatum and D. laeve, for the first time completing the life cycle of this parasite under experimental conditions. The course of parasite development and patency was followed for 26 months post infection (p.i.) using fecal examinations and radiography. The prepatent periods in two of the muskoxen were 91 and 95 days and the patent period in one extended for 23 months. Larval production peaked 13–14 months p.i. On postmortem of two of the muskoxen at months …


The Chondrocranium Of The Mexican Burrowing Toad, Rhinophrynus Dorsalis, Charles C. Swart, Rafael O. De Sá Jan 1999

The Chondrocranium Of The Mexican Burrowing Toad, Rhinophrynus Dorsalis, Charles C. Swart, Rafael O. De Sá

Biology Faculty Publications

The chondrocranium of Rhinophrynus dorsalis is described and illustrated. Autapomorphies of R. dorsalis are the presence of the symplectic cartilage and a cartilaginous process on the ascending process of the palatoquadrate. Synapomorphies of Rhinophrynus shared with the Pipidae are: (1) early formation of the lower jaw and (2) presence of a suprarostral plate. Alternative developmental pathways for the formation of the suprarostral plate are considered. Histological data indicates that the suprarostral plate forms from: (1) the early fusion of the cornua trabeculae with the suprarostral cartilages, (2) an anterior growth of the ethmold plate, and (3) subsequent fusion …


Unidad De Los Anfibios Modernos Como Grupo Natural, Rafael O. De Sá Jan 1999

Unidad De Los Anfibios Modernos Como Grupo Natural, Rafael O. De Sá

Biology Faculty Publications

RESUMEN

La monofilia de la infraclase Lissamphibia ha sido cuestionada. Algunos autores sugieren un origen independiente del Orden Gymnophiona basados en la condición compacta (= estegocrotafía) del cráneo de la cecilias. La presente revisión indica la irrelevancia del estegocrotafismo para establecer las relaciones filogenéticas del grupo. Los datos disponibles sugieren: 1) el estegocrotafismo es secundariamente derivado en cecilias, y 2) Lissamphibia representa un grupo monofilético.

SUMMARY

Unity of modern Amphibians as a natural group

The monophyly of Lissamphibia has been previously questioned. Some authors suggested an independent origin of Gymnophiona based on the solid condition (= stegokrotaphy) of the caecilian …


Alarm Calls Affect Foraging Behavior In Eastern Chipmunks (Tamias Striatus), Jessica K. Baack Jan 1999

Alarm Calls Affect Foraging Behavior In Eastern Chipmunks (Tamias Striatus), Jessica K. Baack

Masters Theses

I used playback experiments to test whether alarm calls affected the foraging behavior of Eastern chipmunks (Tamias striatus). I subjected chipmunks, foraging at artificial feeding stations, to three playback treatments (silent, control noise, and alarm call) and examined changes in vigilant and foraging behavior. Chipmunks responded to alarm calls with a greater degree and duration of vigilant behavior, such as look-ups and alert postures. Chipmunks also ran a shorter distance to cover, ran more directly to cover, and took longer to re-emerge from the burrow after hearing an alarm call. Alarm calls caused individuals to spend more time …


Pfiesteria Piscicida And Dinoflagellates Similar To Pfiesteria, Harold G. Marshall Jan 1999

Pfiesteria Piscicida And Dinoflagellates Similar To Pfiesteria, Harold G. Marshall

Biological Sciences Faculty Publications

Pfiesteria pisiccida is a microscopic, unicellular organism that is classified as both a mixotrophic and heterotrophic dinoflagellate, which has been associated with both fish deaths and a cause of human illness (Burkholder et al., 1992; Glasglow et al., 1995; Burkholder and Glasgow, 1997). This species possesses a complex life cycle that includes motile forms (e.g. zoospores, gametes, amoebae) and a cyst stage that may remain dormant in the sediment (Burkholder et al, 1995b). Pfiesteria piscicida is known to have toxin and non-toxin producing populations, where cyst transformation into the toxic motile zoospores may be initiated by the presence of certain …


Two New Nymphalidae From Western North Carolina: New Subspecies Of Speyeria Aphrodite And Phyciodes Batesii, Ronald R. Gatrelle Dec 1998

Two New Nymphalidae From Western North Carolina: New Subspecies Of Speyeria Aphrodite And Phyciodes Batesii, Ronald R. Gatrelle

The Taxonomic Report of the International Lepidoptera Survey

Two new subspecies are described from Macon County, North Carolina, United States. Speyeria aphrodite cullasaja is characterized by dorsal melanism, especially in females, by usually lacking the dorsal FW basal spots in cell Cu1 and Cu2, and by a narrowed buff marginal band on the ventral HW (sometimes absent in females). Phyciodes batesii maconensis males are characterized by wholly yellow ventral hind wings devoid of any dark marginal dusting or whitish crescents; and females occasionally possessing, lightly dusted, brown margins and rarely having a silvered marginal ventral HW spot. PPhyciodes batesii maconensis larvae are gregarious Aster feeders. Females are …


The Prairie Naturalist Volume 30, No.4 December 1998 Dec 1998

The Prairie Naturalist Volume 30, No.4 December 1998

The Prairie Naturalist

FISH COMMUNITY AND WATER QUALITY CHANGES IN THE BIG SIOUX RIVER ▪ D. Dieterman, and C. R. Berry, Jr.

EFFECTS OF PARASITOIDS AND COMPETITION ON CLUTCH SIZE OF A GALLING MIDGE ▪ D. J. Kinateder and S. J. Stein

RESPONSE OF BREEDING SEASON BLUE-WINGED TEAL TO DECOY TRAPPING ▪ P. R. Garrettson

COMPARISON OF POINT-COUNT AND WADE-FLUSH METHODS FOR COUNTING DUCKS ▪ G. M. Linz, C. P McMurl, H. J. Homan, and D. L. Bergman

Reviewers 1998

Author Index - Volume 30

Subject Index - Volume 30

Announcements


The Rediscovery, Taxonomy, And Biology Of Chlosyne Gorgone Gorgone And Chlosyne Ismeria (Nymphalidae) In Burke County, Georgia, Ronald R. Gatrelle Nov 1998

The Rediscovery, Taxonomy, And Biology Of Chlosyne Gorgone Gorgone And Chlosyne Ismeria (Nymphalidae) In Burke County, Georgia, Ronald R. Gatrelle

The Taxonomic Report of the International Lepidoptera Survey

On April 24, 1993 a colony of Chlosyne gorgone gorgone was found in Orangeburg County, South Carolina, United States. This led to the rediscovery on April 27, 1993 of C. g. gorgone at its type locality in Burke County, Georgia. This species had not been seen or collected anywhere in east coastal Georgia or coastal South Carolina since its description in 1810. The type locality is xeric, scrub oak sandhill. This habitat is generally unsuitable for the survival of later broods. The larvae of nominate gorgone have only been found on Helianthus divaricatus. Topotypical gorgone differ slightly, …


Accurate Classification Of Juvenile Weakfish Cynoscion Regalis To Estuarine Nursery Areas Based On Chemical Signatures In Otoliths, Simon R. Thorrold, Cynthia M. Jones, Peter K. Swart, Timothy E. Targett Nov 1998

Accurate Classification Of Juvenile Weakfish Cynoscion Regalis To Estuarine Nursery Areas Based On Chemical Signatures In Otoliths, Simon R. Thorrold, Cynthia M. Jones, Peter K. Swart, Timothy E. Targett

OES Faculty Publications

We investigated the ability of trace element and isotopic signatures in otoliths to record the nursery areas of juvenile (young-of-the-year) weakfish Cynoscion regalis from the east coast of the USA. Juvenile C. regalis were captured with otter trawls at multiple sites in Doboy Sound (Georgia), Pamlico Sound (North Carolina), Chesapeake Bay (Virginia), Delaware Bay (Delaware) and Peconic Bay (New York), from July to September 1996. One sagittal otolith from each specimen was assayed for Mg/Ca, Mn/Ca, Sr/Ca and Ba/Ca ratios using inductively coupled plasma mass spectrometry (ICP-MS), while delta 13 C and delta 18 O values from the other sagittal …


Deforestation In The Tropics: Reconciling Disparities In Estimates For India, Shaily Menon, Kamaljit S. Bawa Nov 1998

Deforestation In The Tropics: Reconciling Disparities In Estimates For India, Shaily Menon, Kamaljit S. Bawa

Peer Reviewed Publications

Here we examine recent disparate estimates of deforestation obtained for India. We discuss the sources of disparity and the implications of inaccurate estimates and suggest ways in which future attempts at estimating deforestation might reconcile the disparity. Despite the importance of deforestation and its consequences, no attempt has been made to reconcile the different estimates obtained for India.


Apostatic Selection By Blue Jays Produces Balanced Polymorphism In Virtual Prey, Alan B. Bond, Alan Kamil Oct 1998

Apostatic Selection By Blue Jays Produces Balanced Polymorphism In Virtual Prey, Alan B. Bond, Alan Kamil

Papers in Behavior in Biological Sciences

Apostatic selection, in which predators overlook rare prey types while consuming an excess of abundant ones, has been assumed to contribute to the maintenance of prey polymorphisms. Such an effect requires predators to respond to changes in the relative abundance of prey, switching to alternatives when a focal prey type becomes less common. Apostatic selection has often been investigated using fixed relative proportions of prey, but its effects on predator–prey dynamics have been difficult to demonstrate. Here we report results from a new technique that incorporates computer-generated displays into an established experimental system, that of blue jays (Cyanocitta cristata …


Impact Of An Ecological Factor On The Costs Of Resource Acquisition: Fighting And Metabolic Physiology Of Crabs, L. U. Sneddon, F. A. Huntingford, A. C. Taylor Oct 1998

Impact Of An Ecological Factor On The Costs Of Resource Acquisition: Fighting And Metabolic Physiology Of Crabs, L. U. Sneddon, F. A. Huntingford, A. C. Taylor

Ethology Collection

  1. Current game theory models and recent experimental evidence suggests that the strategy an animal adopts in agonistic encounters is determined by individual state. Therefore manipulation of an individual’s state should elicit different behavioural responses. In this paper, mechanisms are examined that underlie state-dependent strategies using Shore Crabs, Carcinus maenas, and how, by altering the environment, behaviour and physiology are affected.
  2. Fights were staged between pairs of male crabs under normoxic and severely hypoxic (< 15 torr) conditions to determine if the metabolic costs of fighting and resource acquisition are affected by water PO2. After fighting, blood and tissue samples from each crab were taken and analysed for metabolites associated with anaerobiosis (L-lactate, glucose and glycogen).
  3. The spectrum …


Theories Of Structure Versus Theories Of Change, Melanie Mitchell Oct 1998

Theories Of Structure Versus Theories Of Change, Melanie Mitchell

Computer Science Faculty Publications and Presentations

The dynamics/computation debate recalls a similar debate in the evolutionary biology community concerning the relative primacy of theories of structure versus theories of change. A full account of cognition will require a rapprochement between such theories and will include both computational and dynamical notions. The key to making computation relevant to cognition is not making it analog, but rather understanding how functional information-processing structures can emerge in complex dynamical systems.


An Addendum To Anthocharis Midea Dos Passos And Klots 1969: Description Of A New Subspecies From Texas, Ronald R. Gatrelle Oct 1998

An Addendum To Anthocharis Midea Dos Passos And Klots 1969: Description Of A New Subspecies From Texas, Ronald R. Gatrelle

The Taxonomic Report of the International Lepidoptera Survey

This paper verifies and expands upon the information presented by dos Passos and Klots in their 1969 systematic revision of Anthocharis midea. Their restriction of the range of A. midea midea to the coastal islands and immediate coast of Georgia and South Carolina, United States is confirmed and expanded north into southern coastal North Carolina. Their range of A. m. annickae is expanded southward from Virginia to central Georgia. A new subspecies, A. midea texana, is described from Texas. Texana is annickae’s ancestor. It differs from annickae only in having greatly reduced black scaling …


Grassland Birds And Habitat Structure In Sandhills Prairie Managed Using Cattle Or Bison Plus Fire, Randall Griebel, Stephen L. Winter, Allen Steuter Oct 1998

Grassland Birds And Habitat Structure In Sandhills Prairie Managed Using Cattle Or Bison Plus Fire, Randall Griebel, Stephen L. Winter, Allen Steuter

Great Plains Research: A Journal of Natural and Social Sciences (through 2013)

Grassland birds are known to respond to specific changes in habitat structure, such as plant height and density. However, the response of grassland bird communities to management induced changes in the regional habitat mosaic are less well understood. Grazing by ungulates and fire regimes play an important role in defining the habitat mosaic in the Great Plains. We provide information on bird abundance, distribution, and habitat structure from similar sandhill prairie landscapes managed traditionally with grazing by cattle (Bos taurus) and by a dynamic bison (Bos bison)-plus-fire regime. Although the two management regimes are dissimilar, only …


Morphogenesis Of Douglas Fir Buds Is Altered At Elevated Temperature But Not At Elevated Co2, Martha E. Apple, Melissa S. Lucash, David M. Olszyk, David T. Tingey Oct 1998

Morphogenesis Of Douglas Fir Buds Is Altered At Elevated Temperature But Not At Elevated Co2, Martha E. Apple, Melissa S. Lucash, David M. Olszyk, David T. Tingey

Environmental Science and Management Faculty Publications and Presentations

Global climatic change as expressed by increased CO2 and temperature has the potential for dramatic effects on trees. To determine what its effects may be on Pacific Northwest forests, Douglas-fir (Pseudotsuga menziesii ) seedlings were grown in sun-lit controlled environment chambers at ambient or elevated (+4°C above ambient) temperature, and at ambient or elevated (+200 ppm above ambient) CO2. In 1995–1996 and 1996–1997, elevated CO2 had no effect on vegetative bud morphology, while the following unusual morphological characteristics were found with greater frequency at elevated temperature than at ambient: rosetted buds with reflexed and loosened outer …


Changes In Small Mammal Community Attributes Associated With Increasing Pine Stand Age In Managed Pine Plantations In Southeastern Virginia, James Douglas Dolan Oct 1998

Changes In Small Mammal Community Attributes Associated With Increasing Pine Stand Age In Managed Pine Plantations In Southeastern Virginia, James Douglas Dolan

Biological Sciences Theses & Dissertations

Loblolly pine plantations were examined at different ages to identify small mammal community attributes in relation to the succession of the plant community. Forest floor and understory plant communities were characterized. Small mammals were collected by Fitch (live) traps and pitfall traps in four age classes during five seasons of study. Fitch live traps and pitfall traps were used in conjunction with one another to obtain the most accurate depiction of the small mammal community. Fitch traps accounted for 65 % of small mammal captures and 7 of 9 species captured. Small mammal abundance and biomass declined with increasing stand …


Vegetation Analysis: A Graphical Analysis Of Plant Succession In Desert Communities Affected By Fire, Jeff Lantow Oct 1998

Vegetation Analysis: A Graphical Analysis Of Plant Succession In Desert Communities Affected By Fire, Jeff Lantow

UNLV Theses, Dissertations, Professional Papers, and Capstones

The Mojave Desert is affected by fire every year. With each fire comes the removal of old growth and, in its place, new growth – consisting primarily of those species which thrive in disturbed areas. The focus of my research is to look at plant communities that have been disturbed by fire, and examine the successional pathway of these disturbed environments. The seven environments I analyzed were burned within the last twenty years and are found in the Coleogyne ramosissima ecotone throughout the Spring Mountain range near Las Vegas, Nevada. The data was collected with randomly chosen circle plots in …