| Human activity is rapidly increasing in Alberta's boreal forest and is facilitating the introduction and spread of non-native species such as earthworms. I found that earthworms were significantly more likely to occur near boat launches and roads than other locations, suggesting that bait abandonment and vehicular transport are key mechanisms of introduction. Probability of earthworm occurrence and extent of spread also increased significantly as road age increased. I used these results to create a model which indicated approximately 9% of northeastern Alberta is likely currently invaded by earthworms. However, in the next 50 years, 49% of this region is predicted to be invaded as development intensifies. Finally, mitochondrial DNA sequencing revealed that multiple introductions of Dendrobaena octaedra have occurred in northern Alberta. As well, genetic diversity was significantly greater at boat launches than roads, indicating that multiple introductions may be more likely to occur at those locations. |
