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Advancements in genetic technology and processing allows for the presence of loose genetic material in the environment to become a resource, capable of assisting habitat and wildlife management efforts by providing information about organisms in a region without having to disturb or disrupt the organisms and environment. This use of environmental DNA has gained traction across biomes, with researchers continuing to test extraction and processing of DNA from various environmental media. However, the high variability in media quality, characteristics, and taxonomic knowledge means that the tested capabilities of eDNA vary wildly depending on the application and species of interest. In this thesis, I focus on the use of eDNA metabarcoding in freshwater streams in Maine, examining the ability and existing libraries of two genetic loci to identify Maine fish and macroinvertebrate species. eDNA results are compared against a traditional specimen-based surveying method utilized by the Maine Department of Environmental Protection and the Penobscot Nation’s Department of Natural Resources, and over time to monitor the success of stream restoration initiatives. While eDNA samples successfully detected fish and invertebrate species in both datasets, no strong correlation was found between benthic macroinvertebrate abundance counts and detected sequence variants. Furthermore, eDNA detection led to highly different community survey results than the specimen-based survey method, and limitations of available reference sequences indicate a strong need for localized references for future eDNA work. While eDNA was able to identify ASVs at a higher clarity than the specimen-based survey method, only 4 taxonomic families were shared between the survey method categorization and eDNA detection. However, eDNA was successful when applied to a broader range of taxa for presence-absence detection and community composition detection, and found that stream communities did change significantly based on installment of large wood addition projects. 

The ratio of the electric to magnetic form factors of the proton, μpGEp/GMp, has been measured for elastic electron-proton scattering with polarized beam and target up to four-momentum transfer squared Q2=5.66(GeV/c)2 using double spin asymmetry for target spin orientation aligned nearly perpendicular to the beam momentum direction. This measurement of μpGEp/GMp agrees with the Q2 dependence of previous recoil polarization data and reconfirms the discrepancy at high Q2 between the Rosenbluth and the polarization-transfer method with a different measurement technique and systematic uncertainties uncorrelated to those of the recoil-polarization measurements. The form factor ratio at Q2=2.06(GeV/c)2 has been measured as μpGEp/GMp=0.720±0.176stat±0.039sys, which is in agreement with an earlier measurement using the polarized target technique at similar kinematics. The form factor ratio at Q2=5.66(GeV/c)2 has been determined as μpGEp/GMp=0.244±0.353stat±0.013sys, which represents the highest Q2 measurement reached using double spin asymmetries with polarized target to date.