Observations of the Long-Toed Salamander, Ambystoma macrodactylum, in Waterton Lakes National Park, Alberta

The ecology of the Long-Toed Salamander (Ambystoma macrodactylum) was studi ed in Waterton Lakes National Park, Alberta, and evidence of its presence w as obtained at nine of thirteen study sites. Populations occurred throughou t the park at elevations from 1280 to 1930 metres in habitat that varied fr om aspen parkland to subalpine forest. Salamander breeding activity occurre d from early April to late June, depending on location. Development of larv ae in lakes or ponds is usually completed in one season (i.e., during one s ummer); however, two-season development was indicated at Summit Lake (eleva tion 1930 m). Mark-recapture data were obtained at Linnet Lake by conductin g night searches and utilizing drift fencing and pitfall traps. A Schumache r-Eschmeyer estimate of between 3274 and 4690 breeding adults (95% confiden ce interval) was obtained for the population. Human impacts included roadwa y mortality and alteration of habitat due to local contamination and/or glo bal effects. The total count of salamander roadway mortalities near Linnet Lake in 1994 was equal to 1.4 to 2.0% of the estimated population of breedi ng adults. Roadway mortality also may have contributed to the unusual femal e biased 3:1 (464 females:155 males) sex ratio obtained for this population . Measurements of pH taken at several aquatic breeding sites indicated a de crease in pH of 1 to 2 1/2 units had occurred in the last twenty-five years ; the change may pose a potential threat to salamanders. Acid precipitation may be the source of this change.