- Mallet, David G.
University of Maine Graduate School
Increasingly, GPS collars are replacing traditional VHF collars in many wildlife research applications, where accurate estimates of an animal's spatial location and habitat use are required. Although GPS collars offer advantages over VHF collars, they can be influenced by vertical structure (e.g., tree boles), horizontal structure (e.g. overhead canopy), and topography (e.g. slope) which affect the percentage of location attempts that are successful (i.e, fix success) and the accuracy if GPS locations. Influences of topography, vegetation, season, satellite configuration, frequency between location attempts, and manufacturer can bias fix success and accuracy of GPS derived location data. Evaluated in many regions of Canada and the United States, these influences have never been investigated in the mesic, heavily forested region of the Acadian forest in eastern North America. Additionally, during companion studies (Chapters 2&3) conducted in northern Maine, GPS collars were equipped on federally threatened Canada lynx (Lynx canadesis) to evaluate spatial requirements, habitat composition of home ranges, and resource selection. Thus, I have evaluated whether fix success and location error of GPS collars differed across habitat classes to be later used in habitat analyses, and I used an information-theoretic approach to model the effects of within habitat structure, slope, aspect, and satellite configuration on fix success and location error. I measured location error and fix success during the leaf-on (May 15-October 14) and leaf-off (October 15-May 14) seasons using two manufacturers of GPS collars (Sirtrack and Lotek), which I deployed at 66 test sites, representing 7 habitat classes, based on tree height, coniferous and deciduous tree composition, and harvest history.