Nunavut supports ten breeding colonies of northern fulmars (Fulmarus glacialis), most of which have rarely been visited on the ground by biologists. During 2000-04, we surveyed six colonies previously thought to support more than 80% of the Canadian Arctic population, which was believed to number about 300 000 breeding pairs. Our counts suggested that the breeding populations of some colonies, especially those at the largest colonies, Cape Searle and Prince Leopold Island, were substantially smaller than previously estimated. Our estimate for the total population of Nunavut was approximately 200 000 occupied sites. However, counts made at fixed monitoring plots at Prince Leopold Island and total colony estimates at Cape Vera, Devon Island, suggested no change in numbers at those colonies since the 1970s. Numbers present at the colony peaked in late June-early July and fell sharply after the end of July. Cyclical attendance, identified in an earlier study, was irregular in period length and was not seen in all years. We concluded that counts of Apparently Occupied Sites (AOS) conducted daily for 10-15 days are the best monitoring protocol for northern fulmars at these Arctic colonies. The great day-to-day variability in counts may have contributed to the large differences between past and recent population estimates.

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We report an apparent long-distance, non-homing movement of 3044 ± 60 m made by a dispersing subadult male Deer Mouse, Peromyscus maniculatus, in southeastern Yukon. Our observation is nearly twice the maximum distance previously recorded for non-homing Deer Mice, and apparently the longest dispersal movement recorded for this species.

Biologists often rely upon data obtained through the live-capture of individuals. Field sampling of animal populations and communities, however, occasionally results in the death of some individuals. Mortality can compromise data collection when experimental designs require individuals to be live-captured, marked and, later, recaptured. When deaths are the result of equipment or technique then it is incumbent upon field researchers to share this information and seek means to reduce capture mortality, for both ethical and data collection reasons (e.g., Jung et al. 2002). Here, we report upon an unusual incident of trap-related mortality of Deer Mice (Peromyscus maniculatus) during field sampling in southeastern Yukon.As part of a study of small mammal communities in the boreal forest near Watson Lake, Yukon (60.06 o N, 128.70 o W), we used Ugglan live-traps (Model 3 Lemming Special, Granhab, Marieholm, Sweden) to live-capture small mammals during September 2003. Unlike some other commonly used types of small mammal live-traps like Sherman traps (H. B. Sherman Traps, Tallahassee, FL) or Longworth traps (Longworth Scientific Instruments Co., United Kingdom), Ugglan traps are constructed of wire mesh and the trap door is elevated and gravity controlled (as opposed to spring loaded). Our traps measured 250 × 78 × 65 mm and had a 6 × 6 mm wire mesh around the top and sides of the trap. A weather shield made of sheet metal covered most of the wire mesh.We captured 85 individual Deer Mice 167 times during our study. Eight individuals (9.4% of individuals captured) were found with their snouts caught in the wire mesh of the traps (Figure 1). Because their upper incisors were through to the other side of the mesh, they were unable to free their snouts and they were lacerated on both sides of the snout. Four were found dead. We released the four live individuals but they did not appear to be in good condition upon release; we did not recapture these four individuals and suspect from their injury and constitution that they may have died sometime after release. All of the individuals that were encountered with their snouts stuck in the wire mesh were found underneath the elevated trap door (Figure 1), where the animals could see outside of the trap. We surmise that trapped Deer Mice were attempting to gnaw through the exposed wire mesh to escape and became caught. No other Deer Mice were found dead in the traps other than those with their snouts caught.During our sampling, we captured 443 individuals, representing five species (Deer Mice and 4 species of arvicoline rodents), a total of 888 times. Live-capture of animals occasionally results in the death of some individuals. Here, we report upon an unusual occurrence of trap-related mortality observed in Deer Mice (Peromyscus maniculatus) captured in wire mesh live-traps during field sampling in southeastern Yukon. Eight of 85 marked individuals (9.4%) were found with their snouts caught in the wire mesh of our live-traps; four of these individuals were found dead. We sugge...