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Global positioning system (GPS) technology has greatly improved the ability to investigate animal ecology at fine spatial and temporal scales but many GPS telemetry-based investigations may be underutilizing the technical capabilities of modern transmitters. We estimated eastern timber wolf (Canis lycaon) movement distance and territory size using variable GPS transmitter sampling frequencies to evaluate the effect of programming details on estimated movement patterns, territory size, and transmitter performance. Estimated movement distance decreased exponentially as sampling frequency was reduced from 1 location every 5 minutes to 1 location every 24 hours, implying that intense sampling frequencies were required for accurate measurement of finescale wolf movements. Wolf territory size estimates using 95% minimum convex polygons declined with decreasing sampling frequency, whereas estimates using adaptive kernel methods were comparable across a range of sampling intensities. Estimated transmitter battery longevity increased as the interval between fixes was lengthened but transmitter efficiency, defined as the number of successful fixes obtained during battery lifespan of the transmitter, was highest with fix intervals of intermediate length.Although GPS transmitters are effective for documenting fine-scale movements of animals, we argue their performance is strongly dependent upon transmitter programming and scale of analysis. Effective use of GPS transmitters will require study-specific assessment of the trade-offs between sampling needs versus transmitter efficiency and longevity.

Although some populations remain stable, moose (Alces alces) density and distribution have been declining in many areas along the southern edge of their North American distribution. During 2006–2009, we deployed 99 vaginal implant transmitters (VITs) in 86 adult female moose in central Ontario, Canada to assist in locating and radiocollaring neonatal moose calves. We monitored radiocollared calves to estimate calf survival and assess the relative importance of specific causes of death. Calves in the western portion of our study area (WMU49) were exposed to a 6‐day general hunting season, whereas calves in the eastern portion of our study area (Algonquin Provincial Park [APP]) were not exposed to hunting. Annual survival for 87 collared calves was greater in the protected area than the harvested area (72.4 ± 6.8% and 55.8 ± 8.3%, respectively) and averaged 63.7 ± 7.1% overall. Predation by wolves (Canis sp.) and American black bears (Ursus americanus) was the dominant cause of death but occurred predominately in APP, whereas other natural mortality agents were 4× more common in WMU49. Only 16% of the collared calves in WMU49 were harvested each year despite a high proportion (approx. 50%) of accessible, public land. Most natural mortality occurred prior to the autumn hunting season such that reductions in natural mortality had little potential to compensate for calf harvest. Overall, calf survival in our study area was moderate to high and our findings suggest predator control or further restrictions of calf hunting in this area is not justified. © The Wildlife Society, 2013

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