Browsing by Subject "Ecological risk assessment"

Now showing 1 - 3 of 3
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    Ecological risk assessments for insect species emerged from western larch imported to northern Minnesota.
    (University of Minnesota, 2004-07) Dodds, Kevin J.; Gilmore, Daniel W.; Seybold, Steven J.
    Forest products imported intra-continentally are potential pathways for introducing native insect species into areas where they were not previously found. While the risk associated with importation of exotic insects into foreign lands is well documented, native species pose similar threats. Ecological risk assessments were conducted on seven species of native insects (Tetropium velutinum LeConte, and Pygoleptura nigrella [Say] [Coleoptera: Cerambycidae], Phaenops drummondi [Kirby] [Coleoptera: Buprestidae], Stephanopachys substriatus [Paykull] [Coleoptera: Bostrichidae], Dendroctonus pseudotsugae Hopkins and Scolytus laricis Blackman [Coleoptera: Scolytidae], and Camponotus noveboracensis [Fitch] [Hymenoptera: Formicidae]) that emerged from western larch logs imported into northern Minnesota. The ecological risk of each species was assessed considering the following factors: economic impact, host specificity, potential for associated organisms, survey potential, pathway potential, establishment potential, and mitigation potential. Following suggestions provided in this document will minimize the likelihood that more western forest insect species will be introduced into Minnesota and other areas of the US.
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    Evaluation Plan for an Earthworm Rapid Assessment Tool Training Program for Land Managers in Northern Hardwood Forest Types in the Western Great Lakes Region
    (2012) Hueffmeier, Ryan M
    Invasive species are causing environmental and economic harm all across the globe. Stopping the introduction of non-native species is the most effective way to deal with them. Non-native earthworms are one particular invasive species affecting the Great Lakes region. There is a need for a rapid assessment method to understand current impacts and identifying areas still earthworm-free. Through research in Minnesota and Wisconsin an Invasive Earthworm Rapid Assessment Tool (IERAT) was developed. The IERAT is a tool for the identification of earthworm impacts using visual indicators. Once earthworms are established there is no known effective way to remove them from the landscape and it is proposed that outreach and education are an effective method to prevent new introductions and to slow the spread of earthworms in northern hardwood forests of the Great Lakes region. This project develops the evaluation framework of the IERAT training. Using the framework evaluators will be assessing the tools’ validity, reliability of land mangers to use the tool, ability of trainers to conduct workshops, best dissemination techniques, changes in participants’ knowledge, attitudes and behaviors from before and after the training, and effects on management decisions. The evaluation plan will be carried out during the second year of training season. The results of the evaluation will be used to make appropriate adjustments to the IERAT and trainings. With earthworm distribution data that the IERAT provides, land managers will be able to develop important areas of protection and work with other interested parties to protect these areas for future generations.
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    Experiments and models to understand gene flow from transgenic fish in different environments.
    (2010-01) Pennington, Kelly Marie
    Transgenic fishes are nearing commercialization for aquaculture around the world. Farmed transgenic fish would likely escape from typical production facilities and interbreed with wild relatives. We tested methodologies for predicting the risk of gene flow from transgenic fish. We conducted the first study of gene flow in confined populations of transgenic animals. In two experiments several generations long, we released growth-enhanced transgenic (T) Japanese medaka (Oryzias latipes) into populations of wild-type (W) medaka in semi-natural environments. Transgene frequencies varied in the first experiment, but transgene frequencies all decreased in the second experiment. We measured six fitness traits in both genotypes, and found that T males were more fertile than W, but W males obtained more matings than T males. Next, we compared fitness traits of W and T medaka under four environments: (A) high food availability, predation absent; (B) high food availability, predation present; (C) low food availability, predation absent; and (D) low food availability, predation present. Overall, T females were more fecund than W, and fecundity was highest in Environment B. Offspring of TW and WT crosses had higher survival to sexual maturity than offspring of two W parents. Fish in Environment A reached sexual maturity sooner than fish in all other environments. W males had a mating advantage in Environments B and C. Finally, we observed gene flow in populations of T and W medaka in Environments A-D for 210 days. The final transgene frequency in Environment A was greater than in Environments C or D. We parameterized a demographic model with fitness trait values collected under the same environments, which predicted that transgene frequency in Environment A would be the highest, but also overestimated transgene frequency compared to observed results. Predicted transgene frequencies overlapped with observations in Environments B and C but not in the more extreme Environments A and D. Our results suggest that risk assessment of gene flow from T to W fish ought to consider the impact of limiting environmental factors on fitness components. Before using models to inform ecological risk assessments, predictions should be confirmed with data collected under relevant environmental conditions.