Deke T. Gundersen

Evidence of Detrimental Effects of Environmental Contaminants on Growth and Reproductive Physiology of White Sturgeon in Impounded Areas of the Columbia River

This study sought to determine whether wild white sturgeon from the Columbia River (Oregon) were exhibiting signs of reproductive endocrine disruption. Fish were sampled in the free-flowing portion of the river (where the population is experiencing reproductive success) and from three reservoirs behind hydroelectric dams (where fish have reduced reproductive success). All of the 18 pesticides and almost all of the 28 polychlorinated biphenyls (PCBs) that were analyzed in livers and gonads were detected in at least some of the tissue samples. Metabolites of p,p′-dichlorodiphenyltrichloroethane (DDT) [p,p′-dichlorodiphenyldichloroethylene (DDE) and p,p′-1,1-dichloro-2,2-bis(4-chlorophenyl)ethane (DDD)] were consistently found at relatively high levels in fish. Some males and immature females showed elevated plasma vitellogenin; however, concentrations were not correlated with any of the pesticides or PCBs analyzed. Negative correlations were found between a number of physiologic parameters and tissue burdens of toxicants. Plasma triglycerides and condition factor were negatively correlated with total DDT (DDD + DDE + DDT), total pesticides (all pesticides detected – total DDT), and PCBs. In males, plasma androgens and gonad size were negatively correlated with total DDT, total pesticides, and PCBs. Fish residing in the reservoir behind the oldest dam had the highest contaminant loads and incidence of gonadal abnormalities, and the lowest triglycerides, condition factor, gonad size, and plasma androgens. These data suggest that endocrine-disrupting chemicals may be accumulating behind dams over time. Overall, results of this study indicate that exposure to environmental contaminants may be affecting both growth and reproductive physiology of sturgeon in some areas of the Columbia River.

Toxic Contaminants in the Urban Aquatic Environment

Management of urban areas to reduce their impact on salmonids requires an understanding of the water quality affecting them, including anthropogenically derived toxic chemicals entering urban waterways used by salmonids. Toxic contaminants create complex problems for aquatic organisms and have important implications for natural resource managers. Toxicity is associated with exposure; therefore, it is important to understand the occurrence and concentration of toxic chemicals, which can range from episodic at high concentrations to chronic exposures at low concentrations. In addition, there are several categories of toxic chemicals with many individual chemicals within each class, which could have similar or very different environmental concentrations, longevity, and toxicity.

Permaculture, A Natural Systems Design Approach For Teaching Sustainability In Higher Education: Pacific University'S B-Street Permaculture Project

Environmental security is dependent on establishing global social systems that mimic natural ecosystems and promote ecological literacy, environmental stewardship, and the equitable distribution of resources and power. The use of fossil fuels as the primary global energy source has resulted in disturbing consequences, some of which must be immediately and judiciously addressed by the global community. As leaders in the global community, institutions of higher education must abandon tradition and embrace innovation to become responsible for imparting the knowledge and skills that produce ecologically literate students. These forward-thinking institutions will embrace experiential, project-based learning practices and produce students who are environmental stewards and active citizens with a deep understanding of local ecosystems and the ways that humans can interact with them in a sustainable way. Permaculture principles have been tested and developed for over 30 years and could serve as an effective tool for teaching the concepts of sustainability in higher education. This paper describes the integration of permaculture principles into the curriculum of a small liberal arts university.

Evaluation of Organochlorine Pesticides and Sex Steroids in Lower Niagara River Lake Sturgeon

Abstract As a long-lived, late-maturing species, lake sturgeon Acipenser fulvescens are vulnerable to the bioaccumulation of contaminants, which may impact reproductive physiology. The purpose of this study was to use a nondestructive method to investigate the relationship between endocrine-disrupting contaminants and sex steroids in lake sturgeon from the lower Niagara River. We screened blood plasma samples from lower Niagara River lake sturgeon (n  =  63) during April and May of 2012 for concentrations of 17 organochlorine (OC) contaminants that may affect endocrine function, as well as for abnormal levels of sex steroids testosterone (T) and 17β-estradiol (E2). We found detectable levels of two OC contaminants in the blood plasma of lake sturgeon, DDE (n  =  21) and γ-BHC (n  =  1). In both cases, plasma contaminant concentration was well below levels known to adversely affect sturgeon reproductive physiology. In addition, qualitative analysis of chromatographs from plasma extracts did not show the pr...