| Ambystoma texanum was studied at three sites in Nemaha County, Nebraska from 10 February 2009 through 4 November 2009. Salamanders began breeding in early March after spring rains. Breeding peaked at two sites in mid-March after which salamanders left the pools. Heavy rainfall stimulated a second, and highly-abbreviated, breeding event at the third site in late April. Females deposited an average of 453 eggs, all of which were laid singly. Eggs hatched in 3-4 weeks with the duration of the larval period 80-90 days. Metamorphosing larvae had a mean snout-vent length (SVL) of 35 mm and a mean total length (TL) of 61 mm. A total of 160 adults were measured, with males exhibiting a mean SVL of 78 mm (138 mm TL) and females exhibiting a mean SVL of 79 mm (138 mm TL). Cranial widths of males were significantly wider than females (11.4 mm and 10.5 mm, respectively). Crayfish burrows were important refugia for adult salamanders as adults were observed in them on numerous occasions. Additional observations included the presence of metacercariae of the fluke Clinostomum marginatum in two salamanders, which represent the first occurrences of the fluke infesting an amphibian in Nebraska. A new population was found in Richardson County, but salamanders were absent from 5 of the 8 sites at which they had been found historically. Fish were present at several sites where salamanders were historically found suggesting that fish invasion prevented successful recruitment. |
