. The Biological bulletin. Biology; Zoology; Marine biology. 232. Figure 2. Corridors of travel of 4 animals (1967) selected to avoid overlap and show- range of variability (N = 36). One-half distance to next trap included in corridors. The fences and traps border forest areas. ''successful" migration. Conversely, the animals may leave the pond anywhere between 0° and 180° and be on the east side of the pond. Considering the amount of dispersion, this type of orientation may actually be more typical of the biologic situation. That a statistically significant number of animals did choose c
. The Biological bulletin. Biology; Zoology; Marine biology. 232. Figure 2. Corridors of travel of 4 animals (1967) selected to avoid overlap and show- range of variability (N = 36). One-half distance to next trap included in corridors. The fences and traps border forest areas. ''successful" migration. Conversely, the animals may leave the pond anywhere between 0° and 180° and be on the east side of the pond. Considering the amount of dispersion, this type of orientation may actually be more typical of the biologic situation. That a statistically significant number of animals did choose consistent headings in relation to the point they entered the pond indicates that the animals tend to use the same track even though their terrestrial retreats may not be closest to the entry point. Additionally, animals determined as taking "poor" headings may correct for their "error" after leaving the pond. Studies utilizing fences at varying distances from breeding ponds in 1966 and 1967 seem to confirm the above suppositions. When migrating in a meadow to and from the pond many animals tend to limit their movements when within 100 m. of the pond to a narrow corridor 10 to 30 m. wide. Some corridors used by the salamanders in 1967 are represented in Figure 2. In 1967 36 animals were caught at the forest border and pond border at entry and exit (4 captures each). The corridor used in crossing the meadow to and from the pond may have little relation to the movement of an animal in the forest. Figure 3 shows capture points of an animal moving in an easterly-westerly corridor at a great angle to a line drawn between capture points at the forest border and in the forest. Time between the last two captures was 6 days. Of the animals collected in successive years, most seem to travel in the same corridor to and from the pond (Fig. 4), although some apparently use dififerent corridors. A pattern of different corridors for entry and exit (seen in 3 animals) may
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