Summary 1.Global positioning system (GPS) radio-telemetry has become an important wildlife research technique worldwide. However, understanding, quantifying and managing error and bias in raw GPS radio-telemetry data sets requires much more work. In particular, error and bias resulting from position (angle away from vertical) and orientation (compass direction) of GPS radio-collars on free-ranging animals is currently unknown. 2. We tested the effects of collar position and orientation on GPS radio-collar performance using five stationary GPS radio-collars. We also investigated the use of positional dilution of precision (PDOP) as a method for screening data with high location errors. 3. Orientation had no statistical effect on fix rates or location errors. The biggest source of variation was attributed to collar position, which resulted in significantly lower performance at angles below 90 ° from vertical. 4. PDOP-based screening was effective and can be used to lower location error, but the trade-off between higher location accuracy and data loss (potentially leading to new bias) must be assessed. Synthesis and applications.The results of this study refine our understanding of error and bias in GPS radio-telemetry data. We suggest that collar orientation can safely be disregarded, whereas radio-collar position remains a large potential source of error and bias. This finding has major implications regarding animal activity and GPS radiotelemetry research. Researchers need to quantify and account for biases resulting from animals moving through heterogeneous terrain and habitats.

ABSTRACT. Landscape connectivity is considered a vital element of landscape structure because of its importance to population survival. The difficulty surrounding the notion of landscape connectivity is that it must be assessed at the scale of the interaction between an organism and the landscape. We present a unique method for measuring connectivity between patches as a function of organism vagility. We used this approach to assess connectivity between harvest, old-growth, and recent wildfire patches in a real forested landscape in southeast British Columbia. By varying a distance criterion, habitat patches were considered connected and formed habitat clusters if they fell within this critical distance. The amount of area and distance to edge within clusters at each critical distance formed the basis of connectivity between patches. We then assessed landscape connectivity relative to old-growth associates within our study area based on species' dispersal abilities. Connectivity was greatest between harvest patches, followed by old-growth, and then wildfire patches. In old-growth patches, we found significant trends between increased connectivity and increased total habitat amount, and between decreased connectivity and increased old-growth harvesting. Highly vagile old-growth associates, such as carnivorous birds, perceive this landscape as connected and are able to access all patches. Smaller, less vagile species, such as woodpeckers, chickadees, and nuthatches, may be affected by a lack of landscape connectivity at the scale of their interaction with old-growth patches. Of particular concern is the northern flying squirrel (Glaucomys sabrinus), which we predict is limited in this landscape due to relatively weak dispersal abilities.

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To test public perception and preference of forest fragmentation trends under current forest management practices, we solicited preferences for harvest patterns from 63 study participants before and after they were provided with educational material on the subject. In addition, we solicited preferences for harvest systems employing different retention patterns. Participants preferred harvest patterns tending away from small, dispersed harvest blocks (i.e., more fragmented) towards larger, more aggregated harvest blocks (i.e., less fragmented). This preference was more pronounced when participants were provided with information that stressed a less fragmented pattern as being ecologically beneficial. This result suggests that the public is willing to accept larger, more aggregated harvest blocks relative to the status quo, especially if provided with information that stresses benefits of that approach. However, participants clearly preferred a harvest system employing dispersed individual tree retention over other systems employing a more concentrated retention pattern. The combination of these results suggests that public acceptability of larger aggregated harvest blocks may depend on the amount of post-harvest retention involved, and that harvest systems employing dispersed individual tree retention will be preferred by the public.Key words: effects of information, environmental perception, forest fragmentation, forest management, human perception, natural disturbance RÉSUMÉAfin d'évaluer la perception publique et la préférence relative aux tendances de fragmentation forestière dans le cadre des pratiques actuelles d'aménagement forestier, nous avons sollicité les préférences en matière de patrons de coupe auprès de 63 participants à une étude avant et après qu'ils aient reçu le matériel éducatif sur le sujet. De plus, nous avons sollicité les préférences en matière de régimes de récolte utilisant divers patrons de rétention. Les participants ont préféré les patrons de récolte qui s'éloignaient des petits blocs de coupe dispersés (c'est-à-dire, plus morcelés) par rapport aux blocs de coupe plus importants et regroupés (c'est-à-dire, moins morcelés). Cette préférence était plus prononcée après que les participants eurent reçu de l'information qui soulignait qu'un patron moins morcelé était bénéfique au niveau écologique. Ce résultat laisse entendre que le public est prêt à accepter des blocs de coupe plus importants et moins morcelés par rapport au status quo, surtout si on lui apporte de l'information qui souligne les bienfaits de cette approche. Cependant, les participants ont nettement préféré un régime de récolte utilisant une réten-tion dispersée d'arbres individuels par rapport aux autres régimes utilisant un patron de rétention plus concentré. La combinaison de ces résultats laisse entendre que l'acceptation par le public de blocs de coupe plus grand et moins morcelés dépend du niveau de rétention après coupe envisagé et que les régimes de récolte utilisant une rétention dispersée d'arbres individ...