Ecology and Evolutionary Biology Commons^™

Hydrodynamic Mediation Of Density-Dependent Growth And Adult-Juvenile Interactions Of A Spionid Polychaete, Brent T. Hentschel, Amy A. Larson

Environmental Science and Management Faculty Publications and Presentations

Abstract We performed an experiment to test the effects of adult density on the growth rates of juvenile Polydora cornuta. Our experiment was performed in three identical counter-rotating annular flumes, each set to one of three different flow speeds for a period of 3 d (U 5mm = 3, 6, or 12 cm s^-1 , where U_5mm = velocity measured 5 mm above bottom). We implanted replicate vials containing a premeasured juvenile P. cornuta and either 0, 2, or 5 adults into a 2-cm layer of sediment in the flume. The relative growth rates of the juveniles …

Variation In The Response Of Crustacean Zooplankton Species Richness And Composition To The Invasive Predator Bythotrephes Longimanus, Angela L. Strecker, Shelley E. Arnott, Norman D. Yan, Robert Girard

Environmental Science and Management Faculty Publications and Presentations

The predacious invertebrate Bythotrephes longimanus has invaded >90 freshwater lakes in North America. There is some evidence that B. longimanus has a negative effect on summer zooplankton species richness; however, no study has examined the effect of B. longimanus throughout the ice-free season in more than one lake. We visited 10 invaded and 4 reference lakes every 2 weeks from May to September, collecting B. longimanus, crustacean zooplankton, and water chemistry samples. Composite samples were pooled across the study season for each lake. Bythotrephes longimanus significantly reduced cladoceran species richness, diversity, and abundance, and the total zooplankton community also exhibited …

Impact Of Bythotrephes Invasion On Zooplankton Communities In Acid-Damaged And Recovered Lakes On The Boreal Shield, Angela L. Strecker, Shelley E. Arnott

Environmental Science and Management Faculty Publications and Presentations

Invasive species introductions into freshwater ecosystems have had a multitude of effects on aquatic communities. Few studies, however, have directly compared the impact of an invader on communities with contrasting structure. Historically high levels and subsequent reductions of acid deposition have produced landscapes of lakes of varying acidity and zooplankton communitystructure. We conducted a 30-day enclosure experiment in Killarney Provincial Park, Ontario, Canada, to test the effects ofBythotrephes longimanus, an invasive invertebrate predator, on two contrasting zooplankton communities at different stages of recovery from acidification: recovered and acid damaged. Bythotrephes significantly decreased zooplankton biomass and abundance in both communities but …

Biotic Resistance To Invasion: Native Predator Limits Abundance And Distribution Of An Introduced Crab, Catherine E. De Rivera, Greg M. Ruiz, Anson Hines, Paul Jivoff

Environmental Science and Management Faculty Publications and Presentations

Introduced species frequently escape the natural enemies (predators, competitors, and parasites) that limit their distribution and abundance in the native range. This reduction in native predators, competitors, and parasites may result in ecological release in the introduced range. However, biological interactions also can limit the establishment and spread of nonnative populations. The extent to which such biotic resistance occurs is poorly resolved, especially for marine ecosystems. Here we test whether a native predator, the blue crab Callinectes sapidus, affects the abundance and geographic range of the introduced European green crab Carcinus maenas in eastern North America. Both crab species …

Woodland Amphibian Distribution In Parks And Greenspaces Of The Portland, Oregon Metropolitan Area: A Multiple Scale Investigation, Laura A. Roberts

Dissertations and Theses

Loss of biodiversity due to habitat fragmentation is worldwide problem. With growing human populations and increasing urbanization, it is a necessity to conduct studies on wildlife occurring in urban areas. Currently there is a deficit of research investigating woodland amphibians in urban environments. My objectives were to describe amphibian species richness and abundance in the Portland, Oregon, Metropolitan region, and relate patterns of variation to variables at three increasingly large spatial scales: 1) local microenvironmental (i.e. amphibian/substrate interaction), (2) macrohabitat/patch (i.e. park or greenspace), and 3) landscape (surrounding parks and greenspaces). Environmental variables occurring within the three spatial scales were …

The Kin Composition Of Social Groups: Trading Group Size For Degree Of Altruism, Leticia Avilés, Jeffrey Alan Fletcher, Asher D. Cutter

Complex Systems Faculty Publications and Presentations

Why some social systems form groups composed of kin, while others do not, has gone largely untreated in the literature. Using an individual-based simulation model, we explore the demographic consequences of making kinship a criterion in group formation. We find that systems where social groups consist of one generation breeding associations may face a serious trade-off between degree of altruism and group size that is largely mediated by their kin composition. On the one hand, restricting groups to close kin allows the evolution of highly altruistic behaviors but may limit group size to suboptimal levels, the more severely so the …

Projecting Range Expansion Of Invasive European Green Crabs (Carcinus Maenas) To Alaska: Temperature And Salinity Tolerance Of Larvae, Anson Hines, Greg Ruiz, Natasha Gray Hitchcock, Catherine E. De Rivera

Environmental Science and Management Faculty Publications and Presentations

The European Green Crab (Carcinus maenas) is a global invader, successfully colonizing many world regions and having significant ecological and economic impacts. The Green Crab colonized western North America in the late 1980s, spreading primarily northward from the initial establishment in San Francisco Bay to several other bays in northern California, Oregon, and Washington. Initial analysis, based largely upon temperature tolerance of postlarval crabs, suggests Green Crabs will continue to spread and become established throughout much of Alaska. However, establishment of self-sustaining populations in Alaska may be restricted by environmental conditions for reproduction and larval development, instead of the broad …

Relationships Between Needle Nitrogen Concentration And Photosynthetic Responses Of Douglas-Fir Seedlings To Elevated Co2 And Temperature, James D. Lewis, Melissa S. Lucash, David M. Olszyk, David T. Tingey

Environmental Science and Management Faculty Publications and Presentations

• Here we examined correlations between needle nitrogen concentration ([N]) and photosynthetic responses of Douglas-fir (Pseudotsuga menziesii) seedlings to growth in elevated temperatures and atmospheric carbon dioxide concentrations ([CO₂]).
• Seedlings were grown in sunlit, climate-controlled chambers at ambient or ambient+3.5^° C and ambient or ambient +180 μmol mol^-1 CO₂ in a full factorial design. Photosynthetic parameters and needle [N] were measured six times over a 21-month period.
• Needle [N] varied seasonally, and accounted for 30–50% of the variation in photosynthetic parameters. Across measurement periods, elevated temperature increased needle [N] by 26% and light-saturated …

Book Review Of, Principles Of Terrestrial Ecosystem Ecology., Ruth D. Yanai, Melissa S. Lucash, Phillip Sollins

Environmental Science and Management Faculty Publications and Presentations

Reviews the book "Principles of terrestrial ecosystem ecology" by Francis Stuart Chapin III, Pamela A. Matson, and Harold A. Mooney.

Stomatal Responses Of Douglas-Fir Seedlings To Elevated Carbon Dioxide And Temperature During The Third And Fourth Years Of Exposure, James D. Lewis, Melissa S. Lucash, David M. Olszyk, David T. Tingey

Environmental Science and Management Faculty Publications and Presentations

Two major components of climate change, increasing atmospheric [CO₂] and increasing temperature, may substantially alter the effects of water availability to plants through effects on the rate of water loss from leaves. We examined the interactive effects of elevated [CO₂] and temperature on seasonal patterns of stomatal conductance (g_s), transpiration (E) and instantaneous transpiration efficiency (ITE) in Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) seedlings. Seedlings were grown in sunlit chambers at either ambient CO₂ (AC) or ambient + 180 µmol mol^-1 CO₂ (EC), and at ambient temperature (AT) or ambient + 3.5° …

Reconnaissance Of Pharmaceutical Chemicals In Urban Streams Of The Tualatin River Basin, Oregon, 2002, Stewart A. Rounds, Micelis C. Doyle, Patrick M. Edwards, Edward T. Furlong

Environmental Science and Management Faculty Publications and Presentations

A reconnaissance of pharmaceutical chemicals in urban streams of the Tualatin River basin was conducted in July 2002 in an effort to better understand the occurrence and distribution of such compounds, and to determine whether they might be useful indicators of human-related stream contamination. Of the 21 pharmaceutical chemicals and metabolites tested, only 6 (acetaminophen, caffeine, carbamazepine, codeine, cotinine, and sulfamethoxazole) were detected in filtered stream samples from 10 sites. The concentrations of most of the detected compounds were relatively low (less than 0.05 microgram per liter). The most frequently detected compounds were cotinine (a nicotine metabolite, 8 of 10 …

Factors Influencing Oviposition Among Pond-Breeding Amphibians: Exotic Vegetation, Oviposition Braces, And Cover, Catherine Mary Callison

Dissertations and Theses

I examined oviposition in four pond-breeding amphibians (northwestern salamander [Ambystoma gracile], long-toed salamander [Ambystoma macrodactylum], Pacific treefrog [Hyla regilla], northern red-legged frog [Rana aurora aurora]), at Burlington Bottoms, a lowland riverine site in northwestern Oregon, to determine whether differential use of native versus exotic plant substrates occurs. I found differential use in all four species, but use was inconsistent with the hypothesis that selection for native plants (or selection against exotic plants) was occurring. If selection was occurring, the pattern implied that reed canarygrass (Phalaris arundinacea), a widespread exotic in this lowland system, was sometimes favored. However, inconsistent use of …

Avian And Mammalian Use Of Three Small Urban Wetlands Invaded By A Pest Species, Reed Canarygrass (Phalaris Arundinacea L.), Laurie Dizney

Dissertations and Theses

Small urban wetlands are being destroyed and degraded at an alarming rate. One result of degradation is invasion by pest species, such as reed canarygrass (Phalaris arundinacea L. ). Reed canarygrass forms virtual monocultures in a wide range of wetland types. Wetlands normally have high plant species richness and abundance, which is widely believed to lead to faunal diversity. The purpose of the present study was to determine to what extent birds and mammals use a wetland dominated by reed canarygrass. The research was conducted at Tualatin Hills Nature Park in Beaverton, Washington County, Oregon. I examined three sites …

Water Rights As Contested Terrain: The Case Of Tenmile Creek, Oregon, Marcie L. Allen

Dissertations and Theses

This thesis examines the complex conflict over water rights at Tenmile Creek, located along the south central Oregon Coast. The research is an exploratory case study identifying the main motivations of actors, the constraints they faced, and the conditions that encouraged or dissuaded collaborative behavior.

The main objectives are (1) to refine the understanding of the relationship between societies and their physical environment in market societies that are both motivated to exploit and preserve natural resources and, (2) to explore the kinds of institutional arrangements that may be required to manage the water supply in a collaborative and sustainable manner. …

Seasonal Patterns Of Photosynthesis In Douglas Fir Seedlings During The Third And Fourth Year Of Exposure To Elevated Co2 And Temperature, James D. Lewis, Melissa S. Lucash, David M. Olszyk, David T. Tingey

Environmental Science and Management Faculty Publications and Presentations

The interactive effects of elevated atmospheric CO₂ and temperature on seasonal patterns of photosynthesis in Douglas fir (Psuedotsuga menziesii (Mirb.) Franco) seedlings were examined. Seedlings were grown in sunlit chambers controlled to track either ambient (~400 p.p.m.) CO₂ or ambient +200 p.p.m. CO₂, and either ambient temperature or ambient +4 °C. Light-saturated net photosynthetic rates were measured approximately monthly over a 21 month period. Elevated CO₂ increased net photosynthetic rates by an average of 21% across temperature treatments during both the 1996 hydrologic year, the third year of exposure, and the 1997 hydrologic year. Elevated …

The Dynamics Of The Planktonic Communities Of Two Oregon Reservoirs, Miguel Angel Estrada

Dissertations and Theses

From June 1998 to July 1999, the dynamics of the plankton in Hagg Lake and Barney Reservoir were studied with the purpose to identify the succession dynamics of the planktonic species, to test the Plankton Ecology Group (PEG) model, and to explore the relationships between these successions and the physical and chemical variables.

The Impacts Of The Introduced European Green Crab, Carcinus Maenas, On Selected Bivalves And Meiofaunal Communities, Zasha A. Bassett

Dissertations and Theses

This thesis examines the potential impact of the invasive green crab, Carcinus maenas, in Yaquina Bay, Oregon. I sampled the current extent of crab colonization in the intertidal zone of Yaquina Bay using a standardized trapping regimen in selected intertidal sites in August and September 1999. I also evaluated the potential impacts of C. maenas on the commercially important bivalve, Crassotrea gigas. Carcinus' preferred size ranges of C. gigas and other species were experimentally determined. Additionally, Carcinus species preference for C. gigas was examined in relation to two common bivalves, Mytilus trossolus and Macoma nasuta. Experiments were …

Acorn Foraging As A Means To Explore Human Energetics And Forge Connections To Local Forests, Jeffrey J. Gerwing, Pamela Lockwood, Christopher Uhl

Environmental Science and Management Faculty Publications and Presentations

Jeffrey Gerwing, Pamela Lockwood, and Christopher Uhl describe a rather unusual ecology laboratory/field exercise that utilizes abundant oak habitats of central Pennsylvania. For those readers not blessed with an abundant supply of oaks nearby, perhaps other species could be substituted. The exercise is unusual in two ways. It offers a new undergraduate ecology activity, and it offers opportunities for students to relate other disciplines to their science course.

In "the good old days" of higher education each discipline offered its menu of courses and expected students to make appropriate connections among the courses of their major, minor, and general education. …

Internal Temperature Of Douglas-Fir Buds Is Altered At Elevated Temperature, Martha E. Apple, Melissa S. Lucash, David M. Olszyk, David T. Tingey, Donald L. Phillips

Environmental Science and Management Faculty Publications and Presentations

Pseudotsuga menziesii (Douglas-fir) saplings were grown in sun-lit controlled environment chambers at ambient or elevated (4°C above ambient) temperature. We measured internal temperatures of vegetative buds with thermocouple probes and compared temperatures of normal buds and abnormal buds with loosened, rosetted outer scales in elevated temperature chambers. The abnormal buds had higher and earlier peak daily temperatures than normal buds. Elevated temperature may influence the internal temperature of buds and contribute to the development of abnormal, rosetted buds with loosened outer scales. Abnormal bud development may alter branching patterns and allometry of Douglas-fir trees subjected to climatic change.

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 …

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.

Temperature Sensitivity Of El Tor 01, Classical 01, And 0139 Vibrio Cholerae, Michelle Angela O'Neill

Dissertations and Theses

Vibrio cholerae has long been recognized as the causative agent of the disease cholera, but what has only become evident in recent years is the role of the environment in cholera. The cholera bacterium is found autochthonously in the marine and estuarian environment, and if there is any hope of controlling the disease the environmental aspects must be understood.

The central questions addressed in this study were how bacterial survival was influenced by temperature and the role that available nutrients play in V. cholerae survival. Survival of three different V. cholerae strains [classical (01); El Tor (01), and El Tor …

An Ecology Problem Book, Marc Mangel, Paul Switzer, Sarah M. Eppley

Biology Faculty Publications and Presentations

This problem book has many objectives:

• To get you to think about the course each night: do not wait until the last minute to begin working on the problems.
• To get you to deal with data. Statistics courses that you take in the future will be more meaningful once you understand the kinds of data that arise in ecological studies.
• To get you to be more comfortable with theoretical and quantitative methods. Not every ecologist uses those methods, but one should not be put off by them.
• To familiarize you with material as it appears in the professional literature.

Human Trampling In The Upper Rocky Intertidal: Trampling And Recovery In Barnacle Mediated Succession, Timothy Lawrence Grubba

Dissertations and Theses

Marine intertidal ecosystems are vulnerable to human interference, because trampling can be a significant problem. I studied the impacts of trampling on community patterns and succession in a rocky intertidal habitats. This study was divided into two phases: (1) a trampling phase and (2) a recovery phase. Both phases are focused on two barnacles, Balanus glandula and Chthamalus dalli, and on fucoid and red algae. The trampling phase tested the effects of trampling on these organisms. The effects of herbivores, primarily limpets (Collisella digitalis) were also tested to determine whether anthropogenic (trampling) and natural (herbivory and limpet …

Final Environmental Impact Statement For The Bal'diyaka Interpretive Center At Gregory Point On The Oregon Coast In Coos County, Joseph A. Maser

Environmental Science and Management Faculty Publications and Presentations

The Confederated Tribes of Coos, Lower Umpqua and Siuslaw Indians, in partnership with the Coos Bay District of the Bureau of Land Management (BLM) are proposing to construct and operate an interpretive center near or on the South Coast of Oregon, near Coos Bay. The Bal'diyaka Interpretive Center is envisioned to contain a 51,000 square foot main building, a recreated coastal Indian village, an ethnobotanical interpretive trail, vehicular circulation and parking, and utilities infrastructure.

This Environmental Impact Statement analyzes four alternatives for this proposed interpretive center. The proposed action of the BLM would locate the Bal'diyaka Interpretive Center on Gregory …

An Ecology Field Project Book, Marc Mangel, Paul Switzer, Sarah M. Eppley

Biology Faculty Publications and Presentations

An ecological field project book, produced by the authors in conjunction with the University of California, Section of Evolution and Ecology and Center for Population Biology.

Limnology Of Two New Lakes, Mount St. Helens, Wa, Valerie Jean Kelly

Dissertations and Theses

Coldwater Lake and Castle Lake are two new lakes which were formed in the aftermath of the volcanic eruption of Mount St. Helens, WA in May, 1980. This research describes the limnology of these lakes ten years later, and includes physical, chemical, and biological parameters. The two lakes are compared and contrasted. Previous research on the eruption and its aftermath, as well as earlier studies of the lakes are described.

Frequency-Dependent Seed Dispersal By Ants Of Two Deciduous Forest Herbs, Brent H. Smith, Catherine E. De Rivera, Cara Lin Bridgman, John J. Woid

Environmental Science and Management Faculty Publications and Presentations

Two co—occurring deciduous forest myrmecochores, Asarum canadense and Jeffersonia diphylla, release their seeds at approximately the same time, and therefore potentially compete for ants as dispersers. Within a single woodlot, we placed seeds of both species inside a dense Jeffersonia population away from Asarum plants, inside a dense Asarum population away from Jeffersonia plants, and in a site where plants of neither species occurred. No preference was exhibited by ants where natural populations were absent. Preference at the other two sites was frequency dependent: ants preferred seeds of the introduced species. Species preferred by ants have higher seed and …

A Multivariate Test Of Evolutionary Stasis In Homo Sapiens, Jon Geoffrey Kleckner

Dissertations and Theses

In the past, efforts to prove or disprove stasis in hominids have relied upon univariate tests such as Students's t-test. Severe methodological and interpretive problems arise from the misapplication of univariate statistics to questions concerning variation in shape through time. These are questions best addressed using the multivariate approach of morphometrics. Eighteen cranial dimensions drawn from 33 mid and late Pleistocene Homo sapiens were examined using principal component analysis (PCA). PCA divided the sample into two distinct morphologies. Archaic Homo sapiens of the mid Pleistocene clustered with Wurm I neanderthals and apart from post Gottweig early anatomically modern Homo sapiens. …

The Distribution Of Zooplankton In Selected Oregon Lakes, Mary Elizabeth Claska

Dissertations and Theses

Zooplankton samples were collected from 166 Oregon lakes. The lakes included a wide range in size, trophic status, and water quality. Lakes were located throughout the state. Zooplankton were identified using standard taxonomic keys and counted. Seventy-four species were identified from the 200 total samples, including 32 species of cladocera, 22 copepods, and 11 rotifers. Two species of copepod were recorded for the first time in Oregon: Diaptomus mississippiensis and Diaptomus pallidus. Seven species had widespread distributions throughout most of the watersheds in the state. Seventeen other species had distributions restricted to eastern, central, or western Oregon. The remaining …