Physical Sciences and Mathematics Commons^™

Northern Range Expansion And Coastal Occurrences Of The New Zealand Mud Snail Potamopyrgus Antipodarum (Gray, 1843) In The Northeast Pacific, Timothy Mathias Davidson, Valance E. F. Brenneis, Catherine E. De Rivera, Robyn Draheim, Graham E. Gillespie

Environmental Science and Management Faculty Publications and Presentations

The New Zealand mud snail Potamopyrgus antipodarum (Gray, 1843) is a common invasive species in fresh and brackish water ecosystems in Europe, Australia, Japan, and North America. In some invaded habitats, P. antipodarum can reach high densities (over 500,000 snails m^-2) and dominate the biomass of the benthos, leading to detrimental impacts to native biota and changes in ecosystem dynamics. We report the previously unpublished occurrence of P. antipodarum in thirteen fresh and brackish water systems adjacent to the Pacific coast of North America including a new northern range for P. antipodarum: Port Alberni, Vancouver Island, British …

Dispersal Limitation And Climate-Related Environmental Gradients Structure Microcrustacean Composition In Freshwater Lakes, Ellesmere Island, Canada, Angela L. Strecker, Rebecca Milne, Shelley E. Arnott

Environmental Science and Management Faculty Publications and Presentations

Dramatic environmental change is expected in the Arctic, yet little is known about the occurrence and community composition of microcrustaceans in Arctic lakes and how this will be influenced by future environmental change. We sampled and calculated relative abundances of microcrustacean species in 54 lakes on Ellesmere Island, Canada. New species records on Ellesmere Island included Daphnia umbra, Tachidius discipes, and Artemeopsis stefanssoni. Daphnia middendorffiana/tenebrosa was the most common taxon and often dominated microcrustacean assemblages, likely a result of its pigmentation, which offers resistance to ultraviolet radiation. Species richness was positively associated with nutrients, dissolved organic carbon (DOC), temperature, calcium, …

Green Crab Control: A Removal Effort In A Shallow Central California Estuary, Amy A. Larson, C. E. De Rivera, G. M. Ruiz, E. D. Grosholz, Mark D. Sytsma

Environmental Science and Management Faculty Publications and Presentations

Goal: To test the feasibility and effects of locally removing a well-established population of a marine organism with pelagic larvae. Removal of adult European green crabs (Carcinus maenas) from Bodega Harbor as a model system to develop and inform management options for eradication, rapid response, and control of marine invaders.

Rapid Assessment Of 2008-2012 Highway Development Projects In Region 6: Threats And Opportunities To Terrestrial Wildlife Resources, Sandra L. Jacobson, Catherine E. De Rivera, Kathleen Armstrong, Rebecca Aaby, Nadia Jones

Environmental Science and Management Faculty Publications and Presentations

Summaries of Highway Development Projects in Region 6 National Forests.

This document contains a summary of higher complexity projects selected for their interest to line officers and resource managers. These projects represent not only the current Statewide Transportation Improvement Plan (STIP) projects but also a sample of the types of projects that will be on future STIPs. Thus, readers are urged to glance at the tracking tools and narratives for all forests to gain a quick glimpse of the types of projects potentially facing each forest. The summary has extracted brief information on project locations and types, the program year …

Superior Adaptation To Drought In Rubus Armeniacus (Himalayan Blackberry) In Northwest Oregon, J. Alan Yeakley, Joshua S. Caplan

Environmental Science and Management Faculty Publications and Presentations

Despite the status Rubus armeniacus (Himalayan blackberry) has as one of the most prolific and damaging plant invaders in the Pacific Northwest, we know little about the role of water relations in its success. The information available on invasive blackberry water relations (Fotelli et al. 2001; McDowell and Turner 2002) suggests that an ability to avoid water stress has been critically important to their proliferation in regions with Mediterranean climates (Amor et al. 1998). We had two objectives regarding the role of water relations in the invasive success of R. armeniacus:

Objective 1. Determine if R. armeniacus is better adapted …

Engaging Recreational Fishers In Management And Conservation: Global Case Studies, Elise F. Granek, Elizabeth M.P. Madin, M. A. Brown, Will F. Figueira, Darren S. Cameron, Zeb Hogan, Gerry Kristianson, Pierre De Villiers, Jack E. Williams, John R. Post, S. Zahn, R. Arlinghaus

Environmental Science and Management Faculty Publications and Presentations

Globally, the number of recreational fishers is sizeable and increasing in many countries. Associated with this trend is the potential for negative impacts on fish stocks through exploitation or management measures such as stocking and introduction of non-native fishes. Nevertheless, recreational fishers can be instrumental in successful fisheries conservation through active involvement in, or initiation of, conservation projects to reduce both direct and external stressors contributing to fishery declines. Understanding fishers’ concerns for sustained access to the resource and developing methods for their meaningful participation can have positive impacts on conservation efforts. We examined a suite of case studies that …

Differential Effects Of Understory And Overstory Gaps On Tree Regeneration, Brian Beckage, Brian D. Kloeppel, J. Alan Yeakley, Sharon F. Taylor, David C. Coleman

Environmental Science and Management Faculty Publications and Presentations

Gaps in the forest canopy can increase the diversity of tree regeneration. Understory shrubs also compete with tree seedlings for limited resources and may depress tree recruitment. We compared effects of shrub removal and canopy windthrow gaps on seedling recruitment and understory resource levels. Shrub removal, with the canopy left intact, was associated with increased levels of understory light and soil moisture and coincided with increased species richness and diversity of tree regeneration compared to both control plots and canopy gaps. Canopy windthrow gaps, however, resulted in a more than 500 fold increase in soil nitrate concentrations, and seedling growth …

Invasive Predator, Bythotrephes, Has Varied Effects On Ecosystem Function In Freshwater Lakes, Angela L. Strecker, Shelley E. Arnott

Environmental Science and Management Faculty Publications and Presentations

Bythotrephes longimanus is an invertebrate predator that has invaded the North American Great Lakes and a number of inland lakes, where it preys on crustacean zooplankton. We examined the effect of Bythotrephes on two measures of ecosystem function during a four month observational study of freshwater lakes on the boreal shield. Bythotrephes-invaded lakes had significantly lower epilimnetic zooplankton abundance and production compared to reference lakes. On average, Bythotrephes consumed 34% ofzooplankton production when it was present in lakes. There was some evidence of changes in the timing of zooplankton production, as well as shifts to cooler, less productive habitats, which …