Lesions due to Dracunculus insignis in the legs of raccoons (Procyon lotor) in southern Ontario occur seasonally as most larvigerous females emerge in the spring and early summer (April-June). The pathology of dracunculiasis in the raccoon is described and the transmission of the parasite in the wild is discussed with respect to seasonality and local agricultural practices. Crayfish, fishes and frogs (including tadpoles) were given infective third-stage larvae of D. insignis to test their suitability as paratenic hosts. Most of the larvae fed to adult Rana pipiens and R. clamitans were recovered from the somatic musculature. Larvae had increased in size and were highly infective to raccoons.

Ranges of species are dynamic and respond to long-term climate change and contemporary effects such as habitat modification. We report here that moose ( Alces alces ) have recently colonized coastal temperate rainforests of British Columbia, Canada. Contrary to recent publications, field observations of moose and their sign, combined with their occurrence in wolf ( Canis lupus ) faeces, suggest that moose are now widespread on the coastal mainland and occur on least three islands. Traditional ecological knowledge (information accumulated by aboriginal peoples about their environment) suggests that colonization occurred during the mid 1900s, concomitant with logging of major watersheds that bisect the Coast Mountain Range. Range expansion by moose may have ecological consequences such as alteration of predatorprey dynamics and transmission of disease to native deer ( Odocoileus hemionus ).

Larvae of Dracunculus insignis developed to the infective stage in experimentally infected Cyclops vernalis and C. bicuspidatus thomasi kept at 24 C. The first molt occurred at 8–9 days and the second at 13–16 days. Second- and third-stage larvae are briefly described. Infective larvae were administered to raccoon (Procyon lotor) and mink (Mustela vison) and necropsies were performed at predetermined intervals for the determination of the migratory route. In raccoon, third-stage larvae were recovered from the gut wall and mesentery of the abdominal cavity on the 1st day. Larvae were found in the intercostal muscles by the 5th day and in the subcutaneous tissue of the thorax and abdomen by the 7th day. Development to fourth stage was complete by the 19th day. Sexual differences were apparent by the 34th day and worms were present in subcutaneous tissue of the thorax, abdomen, and inguinal region. Male worms were mature at 60 days and females at 65–70 days. Larvigerous females were found in the extremities as early as 120 days post infection. The prepatent period was 354 (309–410) days. Similar results were obtained from mink. Quantitative data on the distribution of worms in various locations within the final host at different times after infection are included.

Over the interval 1969–1971, carcasses of 1147 mammals taken in Ontario, Canada, were examined for guinea worm. Dracunculus lutrae n. sp., was recovered from otter Lutra canadensis (Schreber). Dracunculus insignis (Leidy 1858) Chandler 1942, was found in raccoon Procyon lotor (L.), mink (Mustela vison Schreber), and fisher (Martes pennanti (Erxleben)). Female worms identified, in the absence of males, as Dracunculus sp. were found in muskrat (Ondatra zibethicus (L.), opossum (Didelphis marsupialis L.), and short-tailed weasel (Mustela erminea L.) from Ontario and a single badger (Taxidea taxus (Schreber)) from Manitoba.Dracunculus lutrae n, sp. is distinguished from other species of Dracunculus which parasitize mammals (namely D. medinensis (Linnaeus 1758), D. insignis, and D. fuelleborni Travassos 1934), by the greater length of males, greater length of spicules and gubernaculum, presence of three pairs of preanal papillae, and the arrangement in two transverse rows of papillae immediately posterior to the anus. A brief redescription of D. insignis from raccoon and mink is given. The taxonomic status of the species of Dracunculus parasitizing mammals is briefly discussed.

Within Ontario Dracunculus insignis (Leidy 1858) Chandler 1942, a common parasite of raccoon, Procyon lotor (L) (prevalence > 50%), and mink, Mustela vison Schreber (prevalence > 50%), is apparently confined to the southern part of the province. In this area D. insignis was also found in fisher, Martes pennanti (Erxleben); and Dracunculus sp. was found in short-tailed weasel, Mustela erminea (L), muskrat, Ondatra zibethicus (L), and opossum, Didelphis marsupialis (L). The distribution of D. insignis coincides with that of raccoon in Ontario, and it is suggested that raccoon may be a reservoir host for this species and that mink became incorporated into its life cycle secondarily. Dracunculus lutrae Chrichton and Beverley-Burton 1973 of the otter, Lutra canadensis (Schreber), was found across the entire province and, in most areas, the prevalence exceeded 75%. During the trapping season (October–April) larvigerous females were found in 20 (44.4%) of 45 otter infected with D. lutrae in southern Ontario, but were absent from the limbs of 132 infected otter from northern Ontario.