Effects of grazing on grassland birds are generally thought to be indirect, through alteration of vegetation structure; however, livestock can also affect nest survival directly through trampling and other disturbances (e.g., livestock-induced abandonment). We extracted data on nest fates from 18 grazing studies conducted in Canada. We used these data to assess rates of nest destruction by cattle among 9 ecoregions and between seasonal and rotational grazing systems. Overall, few nests were destroyed by cattle (average 1.5% of 9132 nests). Nest destruction was positively correlated with grazing pressure (i.e., stocking rate or grazing intensity), but nest survival was higher in more heavily grazed areas for some species. Because rates of destruction of grassland bird nests by cattle are low in Canada, management efforts to reduce such destruction may not be of ecological or economic value in Canada.

The western prairie fringed-orchid is a rare North American orchid restricted to a few remnants of wet to mesic tallgrass prairie. It is federally listed in both Canada and the United States and both countries have developed a recovery plan for the species. Two key management objectives are to monitor population trends and identify beneficial management practices. We used 21 y of data from the Manitoba metapopulation to assess effects of weather and land management on this species. Our results suggest the metapopulation in Manitoba is relatively stable. Western prairie fringed-orchids appear to benefit most from a combination of warm temperatures in the previous growing season followed by cool snowy but short winters and wet springs. Periodic burning (e.g., every 2-3 y) may benefit fringedorchids, whereas grazing may be detrimental. This was not a controlled experiment, however, and gaps in the data may have influenced our results. Prescribed burning is a viable management tool for curtailing woody invasion and both burning and grazing reduce litter and grass cover, but careful consideration of timing, frequency, and intensity of application is required so management does not hinder fringed-orchid reproduction or reduce survival, while also recognizing management requirements may vary among years depending on weather. Long-term studies are particularly valuable for the western prairie fringed-orchid due to its erratic life cycle and fluctuating populations, which complicate studies of environmental and management effects on this species.

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