<p> The distribution of Eisenia rosea, the main host of P. rudis, is influenced mainly by soil moisture and bulk density. Cluster-fly larvae locate hosts by random locomotion through the soil pores, whereupon penetration is induced by a substance present in the worm slime. Penetration occurs mainly on the upper surface of the worm, with fewer penetrations occurring towards either end of the worm. Several species of earthworm, including some which do not normally act as hosts, were infected in the laboratory. </p> <p> The encystment, surface casting, burrowing and autotomising behaviour of E. rosea varies with soil moisture and bulk density. The penetration rate of P. rudis larvae into E. rosea is affected by this behaviour, as well as by the soil pore morphology. The success of maintenance of infected worms is also affected by the worm behaviour, which in turn depends on the soil conditions. </p> / Thesis / Doctor of Philosophy (PhD)

There have been no landscape-scale studies on earthworm populations in Canada comparing vegetation types; previous studies on edge habitats have been conducted in agricultural systems. I examined the spatial variations of earthworm populations by measuring abundance based on regional municipality, vegetation type, and edge habitat. Earthworms were sampled throughout the season across a gradient of vegetation types including meadow, forest edge, and interior at a local-scale; and at the landscape level with vegetation types including meadow, deciduous forest, pine plantation and mixed forest. Regional effects were more significant than vegetation type likely due to a gradient of soil characteristics in southern Ontario; edges had intermediate earthworm abundance and a higher proportion of epigeic species. My research provides insight into the patterns of earthworm populations in southern Ontario and the possible effects of edge creation through landscape fragmentation. Field sampling of earthworm parasitoid cluster-flies (Calliphoridae: Pollenia) using synomones was also discussed.

There have been no landscape-scale studies on earthworm populations in Canada comparing vegetation types; previous studies on edge habitats have been conducted in agricultural systems. I examined the spatial variations of earthworm populations by measuring abundance based on regional municipality, vegetation type, and edge habitat. Earthworms were sampled throughout the season across a gradient of vegetation types including meadow, forest edge, and interior at a local-scale; and at the landscape level with vegetation types including meadow, deciduous forest, pine plantation and mixed forest. Regional effects were more significant than vegetation type likely due to a gradient of soil characteristics in southern Ontario; edges had intermediate earthworm abundance and a higher proportion of epigeic species. My research provides insight into the patterns of earthworm populations in southern Ontario and the possible effects of edge creation through landscape fragmentation. Field sampling of earthworm parasitoid cluster-flies (Calliphoridae: Pollenia) using synomones was also discussed.