. The ecology and life history of the common frog (Rana temporaria temporaria). Rana temporaria. 130 ECOLOGY AND LIFE HISTORY OF THE COMMON FROG surely cover anytliing likely to happen in these islands. It is, of course, probable that if a period of exceptionally severe weather set in so that the ponds froze again, spawning would be prevented, but this is not what is usually meant when it is suggested that the animals are con- trolled by temperature. Rainfall The London charts show clearly that rainfall at the spawn season is not necessary. In 1929, spawning began in dry weather, and continued
. The ecology and life history of the common frog (Rana temporaria temporaria). Rana temporaria. 130 ECOLOGY AND LIFE HISTORY OF THE COMMON FROG surely cover anytliing likely to happen in these islands. It is, of course, probable that if a period of exceptionally severe weather set in so that the ponds froze again, spawning would be prevented, but this is not what is usually meant when it is suggested that the animals are con- trolled by temperature. Rainfall The London charts show clearly that rainfall at the spawn season is not necessary. In 1929, spawning began in dry weather, and continued RAIN. .,^v ^^: :a^Z: -H' d - I I I li J Leal I MARCH 9 APRIL I MARCHI9 FEB 23 Fig. 33. The Relation of Rainfall and Temperature to Spawning in the Two Places where Observers Lived in the Village or Town in which One of the Five First Order Observatories was situated At these observatories, houriy records of weather are kept, (a) Eskdalemuir 1930, (b) Eskdalemuir 1931, (c) Eskdalemuir 1932, (d) Valentia 1932. There is not the shghtest doubt that the weather of these places was as stated. These charts show the very different weather in which frogs spawn. Note particularly that in Eskdalemuir in 1931 there was a frost every night of the previous week, and a falling temperature in this period. In Eskdalemuir in 1932 and at Valentia in the same year, there was hardly any rain. during a period that became a drought, relieved by two small showers late in March. The April rain brought no peak of spawning, for most of the frogs had by then laid their eggs. The wet period at the end of February 1927 did not produce a peak in the spawning. At Eskdale- muir in 1930, there was heavy rain in the later part of the night and the next day after a wet week, but in 1931 no rain fell on the night of. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resembl
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Keywords: ., bookcentury1900, bookcollectionbiodiv, booksubjectranatemporaria
