The Canadian field-naturalist (1924) (19898347053)

Pond at Tenaga, Quebec, May, 1921
Title: The Canadian field-naturalist
Identifier: canadianfieldnat1924otta (find matches)
Year: 1924 (1920s)
Authors: Ottawa Field-Naturalists' Club
Subjects:
Publisher: Ottawa, Ottawa Field-Naturalists' Club
Contributing Library: Harvard University, Museum of Comparative Zoology, Ernst Mayr Library
Digitizing Sponsor: Harvard University, Museum of Comparative Zoology, Ernst Mayr Library

Text Appearing Before Image:
January, 1924) The Canadian Field-Naturalist were now teeming with E. gelidus, even the ones almost dried up. Some of the pools were already- dried up completely; and it thus seems as if a great many fairy-shrimps are killed before their time is up, when they occur in very small pools. In size, they were between 10 and 15 mm. long, and mostly sexually mature (females with ripe eggs, males with big claspers, etc.). I kept some of the specimens collected alive until 16 days after, the females living the longest. May 4 began rainy, but the next three days were clear and warm (temperatures on May 7 between 44° and 76° F.); then followed two rainy days (tem.peratures on May 8 between 44° and 78° F.), and colder (24°-46° F.), snowy and windy weather on May 10, and overcast weather the two following days. On May 13 it was clear and warm (34°-62° F.); and the day after was similar, a real summer day. I was along the Gatineau and in two pools in the depressions among the trees on the rocky hill near the river, between Tenaga and Kirk's Ferry, I found a great many full-grown E. gelidus of both sexes (females with ripe eggs, males with big claspers). The fairy-shrimps had almost more brilliant, metallic, greenish and red-brown colours than I had ever seen before, probably a result of the deep colours of the many dead leaves and the vegetation (algae, etc.) in the water. The latter had a temperature of 43° F. at noon (air 55° F.). These two pools were several feet deep and were probably the result of melting snow. The river in the first two weeks of May rose far beyond its normal level, inundating all the lower land on both sides, but th? pools were found beyond its reach. Fairy-shrimps have not before been observed in these pools. In the pond examined two weeks earlier, many adult E. gelidus were also found on this date (females with ripe eggs); both in this pond and in the 2 pools nearer Kirk's Ferry a few immature individuals were collected. The next 3 days were rainy. May 16 being warm (50°-72° F.), the two other days cooler (40°-56° F.). Then followed two clear and warm days and on May 20 much rain fell from noon on. That day I went again to Billings' Bridge but found no fairy-shrimps in the smaller (almost dried up) pools on the inner part of the pasture, though these had been partly filled again by rain-water. Full-grown specimens of both sexes, IJ cm. long, were, however, common in the large pools, and the females had mostly ripe eggs, although I secured one immature female, 10 mm. long. I kept some of them alive for five days afterwards. May 21 began overcast (temperatures between 48° and 56° F.); but then came a longer period with clear and warm weather, (temperatures on May 28: 48°-68° F.), lasting until the beginning of June, when it changed to hot and sultry (June 3), followed by a thunderstorm and rain-showers (June 4-5). On May 27 I was at Westborough and in the pool in the woods along the new Drive- way from Richmond Road to the Rapids I ob- served a couple of full-grown female E. gelidus (with eggs), swimming around in the deeper part
Text Appearing After Image:
Photograph by D. Jenness Pond at Tenaga, Quebec, May, 1921

Français : Un étang à Tenega (aujourd'hui dans Chelsea), en Outaouais, au Québec) en mai 1921