Denning ecology of the striped skunk in the Canadian prairies: implications for waterfowl nest predation

1. From 1993 to 1995, we studied the summer denning ecology of 40 radio-collared striped skunks Mephitis mephitis (32 females, eight males) during the waterfowl nesting season in Saskatchewan, Canada.
2. Forty-seven natal dens were used by 30 females. Natal den sites were either underground burrows (55%) or holes underneath buildings (45%), and were preferably located in farmsteads.
3. Male and female striped skunks used similar resting sites which consisted of above-ground retreats (57%), underground burrows (23%), buildings (17%) and culverts (3%).
4. Habitat preferences for resting sites did not differ between males and females: both sexes preferred farmsteads and wetlands, whereas managed waterfowl nesting areas, woodland and miscellanous habitats were avoided. Cropland was avoided for both natal dens and resting sites.
5. Females did not simultaneously share natal dens or resting sites, but both types of retreats were occupied by different females over time. Natal dens were occupied for 47 ± 3 days for females using a single den vs. 60 ± 3 days for females using >1 natal dens. Den switching may have been induced by a build-up of faeces.
6. Management of natal den sites such as abandoned farmsteads and buildings may provide an avenue of non-destructive predator management that is less expensive and controversial than exclusion or control.     

Tree-ring growth shows that the significant population decline in Norway began decades before the Black Death

The Black Death (1349–1350 in Norway) is often cited as the cause of a severe population decline and building hiatus in the middle of the 14th century. This paper analyses this hypothesis by matching the Black Death with human and environmental impacts on tree-ring growth. The number of buildings dated by dendrochronology in Norway shows a dramatic decline several decades before the plague. In Norway, the building hiatus, which has parallels in several other places in Europe, dates from the late-13th century almost to the 16th century. The first dated houses built after the plague date from the 15th century and many of the logs have exceptionally wide tree rings compared to timber from other periods. Assuming the rapid growth was because of an open landscape, the trees are likely to have grown on infields of farms abandoned due to the 14th century population decline. Since many of these fast-growing trees germinated in the early-14th century and the number of dated buildings drops dramatically several decades before the plague, the Black Death can hardly be the only reason for the population decline in Norway and one plausible explanation is that some environmental impact occurred decades earlier. The dendroclimatological evidence of cold and wet summers in the years before the plague is suggestive, but historical sources also pinpoint famine due to crop failure. They also tell of farms being abandoned several decades before the plague and mention periods of heavy rainfall and famine in the early-14th century.