Browsing by Subject "Animal monitoring"

Now showing 1 - 2 of 2
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    Accuracy and location success of an ultralite GPS unit
    (University of Minnesota Duluth, 2014) Elfelt, Morgan; Moen, Ronald
    Technological advances in GPS tracking units for wildlife have led to smaller and lighter devices. Increased battery life allows for collection of more locations. Before a new device is used in the field, it is important to evaluate its performance in order to more accurately interpret the raw data collected. Our objective was to determine the accuracy and location success of the G10 Ultralite GPS logger for potential use in a study of wood turtles (Glyptemys insculpta). We conducted stationary and moving tests under a variety of device settings and field conditions. For stationary tests, accuracy was measured by calculating the 50% and 95% circular error probable (CEP) at each test location. The CEP is the radius of a circle centered at the true location which contains either 50% or 90% of locations. We also calculated angular dispersion of each dataset, a measure of the direction and concentration of locations. Moving tests were conducted at two sites where wood turtles occur in order to evaluate the GPS unit performance under expected field conditions. Location success was ≥ 95% for all tests, including moving tests, indicating strong potential for consistent performance in the field. Location accuracy was not affected by snapshot size, location interval, or canopy cover. The angular dispersion values calculated indicated little bias in any compass direction, although smaller datasets had greater bias. The 95% CEP for most tests was < 40 m, demonstrating feasibility for assessment of wood turtle movements and habitat use. Integrating use of a temperature sensor would allow for better determination of aquatic vs. terrestrial behavior. To increase accuracy of GPS datasets, data should be screened to identify and remove outliers, using prior knowledge of animal movement characteristics. The high accuracy and location success documented in our tests combined with low power consumption and high storage capacity demonstrates the potential of the G10 Ultralite as an effective animal tracking device.
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    Status of Mammalian Carnivores and Evaluation of Monitoring Techniques in the Lake Superior Basin
    (University of Minnesota Duluth, 2014) Moen, Ronald; Potts, Kevin; Gilbert, Jonathan
    In this report we summarize current methods used by state, provincial, and federal agencies to monitor carnivores in the Lake Superior basin and discuss alternative techniques that could be used to monitor carnivores. Within the Lake Superior Watershed (LSW) there are now up to 20 carnivore species, ranging in size from the tiny least weasel (Mustela nivalis) to the black bear (Ursus americanus). Varied data sources help determine past and present distribution of carnivores in the LSW, such as museum records, DNR/MNR records, books, and the scientific literature. However, there is no single source for information on carnivores in the LSW. The Mustelidae has 9 species, the Canidae has 4 species, the Felidae have 3 species, the Mephitidae have 2 species, and there is 1 species in the Ursidae and 1 in the Procyonidae. We reviewed literature on the status of each species across it range, and also on status within the Lake Superior Watershed when possible. We - searched for existing records of specific locations available in on-line research collections. We also summarized harvest records of each species when it was available within a jurisdiction. Finally, we summarized the methods currently used to monitor carnivore populations that are in the peer-reviewed literature. For each species we include some data on size, distribution, and harvest when possible. This report can be used as a baseline for distribution and numbers of carnivore species in the Lake Superior Watershed. It would be desirable at some point to search museum collections online again, or in person. Collections from some of the small museums are not likely to be digitized and accessible for internet searches. For the future, it would provide background data for developing monitoring techniques to serve as a basin-wide monitoring protocol that can be adopted (and modified as appropriate) by stakeholder agencies.