I'm pleased to announce the publication of the following papers on ringed seal ecology: Temporal variations in Hudson Bay ringed seal (Phoca hispida) life-history parameters in relation to environmentMagaly Chambellant, Ian Stirling, William A. Gough, and Steven H. Ferguson We related temporal variation in the environment to demographic parameters and body condition of ringed seals (Phoca hispida) in Hudson Bay, near the southern limit of the species' geographic range. Ringed seals harvested by Inuit hunters for subsistence purposes in Arviat, Nunavut, Canada, from 1991 to 2006 were measured and sampled. Ringed seal ovulation rate did not change over time, but pregnancy rate and percent pups in the fall harvest increased in the 2000s, compared to the 1990s. Ringed seals grew faster and attained sexual maturity earlier in life, and the population age structure shifted to younger age classes in the 2000s compared to the 1990s. Ringed seal demographic parameters were characteristic of a population in decline in the 1990s and a growing population in the 2000s. A quadratic polynomial regression best described the relationship between percent pups in the harvest and snow depth, and between pup and adult female body condition index and date of spring breakup, suggesting that ringed seals have evolved to do best within a relatively limited range of environmental conditions. We propose that the decline of ringed seal reproductive parameters and pup survival in the 1990s could have been triggered by unusually cold winters and heavy ice conditions that prevailed in Hudson Bay in the early 1990s, through nutritional stress and increased predation pressure. The recovery in the 2000s may have been augmented by immigration of pups, juveniles, and young adult ringed seals into the study area. We discuss the possibility of a decadal-scale biological cycle that reflects fluctuations in climatic variables, and particularly in the sea ice regime. Journal of Mammalogy 93(1):267-281. 2012 doi: http://dx.doi.org/10.1644/10-MAMM-A-253.1 ---------- Temporal variation in distribution and density of ice-obligated seals in western Hudson Bay, Canada Magaly Chambellant, Nicholas J. Lunn and Steven H. Ferguson Recent unidirectional climatic trends and changes in top predator population ecology suggest that long-term modifications may be happening in Hudson Bay, Canada. Effects of such changes on ice-obligated seal populations are expected but long-term studies are required to differentiate climate-induced changes from natural variation. We conducted strip-transect surveys in late spring in 1995–1997, 1999–2000 and 2007–2008 to estimate distribution, density and abundance of ice-obligated ringed (Phoca hispida) and bearded (Erignathus barbatus) seals in western Hudson Bay. When hauled out, ringed seals preferred land-fast and consolidated pack ice, whereas bearded seals preferred unconsolidated pack ice. Bearded and ringed seal density estimates varied from 0.0036 to 0.0229 seals/km2 of ice and from 0.46 to 1.60 seals/km2 of ice, respectively. Strong inter-annual variations were recorded in the abundance estimates of both species, with the largest abundance estimates in 1995 (104,162 and 1,494 ringed and bearded seals, respectively) and the lowest in 2008 for ringed seals (33,701) and 1997 for bearded seals (278). A sine function best described seal density estimates in western Hudson Bay and suggested a decadal cycle. Previous studies that reported low ringed seal demographic parameters in the 1990s and a recovery in the 2000s supported our interpretation of the survey results. We discuss our results in the context of climate warming and suggest that a long-term decline in ice-obligated seal density estimates may overlay a possible natural decadal cycle. Polar Biology DOI: 10.1007/s00300-012-1159-6 (online first)