The Simuliidae of insular Newfoundland and their dynamics in small streams on the Avalon Peninsula

• Main Author: Lewis, D. J. (David James)
• Format: Thesis
• Language: English
• Published: Memorial University of Newfoundland 1973
• Subjects: Newfoundland
• Online Access: https://research.library.mun.ca/4190/; https://research.library.mun.ca/4190/1/Lewis_DavidJames2.pdf; https://research.library.mun.ca/4190/3/Lewis_DavidJames2.pdf

Three genera and twenty-one species of simuliids are recorded from Newfoundland, viz., three species of Prosimulium, two of Cnephia, and sixteen of Simulium. S. croxtoni, S. excisum, and S. gouldingi are new records for Newfoundland. A key to the simuliids of insular Newfoundland is provided for the mature larvae, pupae, males, and females. -- Sampling of 212 streams across Newfoundland indicated that species of Prosimulium and Cnephia overwinter as larvae, and species of Simulium overwinter as eggs. P. fuscum, P. mixtum, and S. venustum were the most abundant mammalophilic species, while S. latipes was the most abundant ornithophilic species. -- Nine species of simuliids were found in the complex of streams in Pickavance Creek and its six tributaries. Pickavance Creek is a small, shallow, permanent stream about 16 km west of St. John's. -- Sampling in the Pickavance Creek area was accomplished using 10 x 10 x 0.8 cm ceramic tiles. These facilitated collecting of specimens and were of convenient area for population density studies. -- The effects of the following factors on simuliid larval and pupal populations have been investigated: rate of flow, temperature, depth, substrate, light, shade, drift, water chemistry, parasites and predators. -- The seasonal succession of simuliids in Newfoundland is similar to that in other regions of North America, but it occurs later in the year in Newfoundland. The number of generations of multivoltine species of simuliids is usually less in Newfoundland due to the short summer. Apart from these two differences, the habits and biology of Newfoundland simuliids are similar to those of other areas on the continent, and the insular habitat apparently does not affect the ecology and bionomics of these blackflies.