Long-Toed Salamander

Last Review/Updated: May 30, 2002

Ambystoma macrodactylum

Description

This slender salamander can reach a total length of 140 mm. It is browny-gray to black in colour and is easily identified by a vivid yellow stripe running down its back, which dulls with age. The stripe is wavy and sometimes patchy. In addition, the long-toed salamander has white flecks on its sides and feet.

Natural History

Though generally secretive, like most salamanders, the long-toed salamander can be seen during April and May when adults are migrating to breeding ponds. Juveniles may also be seen in September when they are seeking hibernation sites. Though they are almost entirely nocturnal, adults may be found during the day under rocks, decaying logs, or other debris, or even under ground, near bodies of water: ponds, lakes, or sometimes even streams. In Alberta, they are often found in habitats modified by human activity, such as borrow pits. Adults tend to remain close to the breeding pond, but they have been found almost a kilometre away from their presumed breeding pond. The preferred food appears to be small worms and insects. The long-toed salamander is currently on the Yellow B List in the Status of Alberta Wildlife report because it is naturally rare with a patchy distribution.

Breeding

Adults migrate to breeding ponds in April or May, often before the ponds are clear of ice. Breeding ponds tend to be relatively shallow (<1 m) and not necessarily permanent. Ponds free of fish appear to be required for successful breeding. The eggs are laid either singly or in clusters on submerged vegetation or on the bottom. The eggs hatch roughly three weeks later, depending upon the water temperature.

Larvae

The larvae are a grey or light-brown in colour with dark flecks and a silvery belly. When first hatched, larvae are only about 15 mm long, but they can grow up to 60-70 mm before transforming in late August; however, in some locations they may overwinter before transforming.

Distribution

In Alberta, the long-toed salamander is limited to the western margin of the province. They are found in subalpine to alpine areas beneath an elevation of roughly 2800 m. Their distribution in the mountains is likely controlled by the number of possible breeding ponds and dispersal routes. Despite their restricted distribution in Alberta they are widely found in British Columbia.

Monitoring

Because long-toed salamanders are primarily nocturnal, they are difficult to locate outside of the breeding season. In addition, unlike frogs and toads, salamanders do not call. Nonetheless, it is during the breeding season that long-toed salamanders are easiest to find when they congregate at breeding ponds.

Map of Alberta showing distribution of species limited to the western boarder

Breeding Survey

Since breeding can occur from April to May, depending upon the time of snowmelt, several trips to potential breeding sites may be required to determine the exact time of breeding. An estimate of the breeding population size can be obtained by conducting weekly evening surveys of transects along the water's edge.

Egg Masses and Larvae

Identifying eggs and larvae of amphibians can be quite challenging. Salamander eggs are generally laid individually, rather than in strings or clumps. However, because eggs can quickly become covered with silt, estimating reproductive success through counting eggs is very difficult.

Once eggs hatch, in early to late May, larvae can be observed. Salamander larvae are relatively easy to identify because of their conspicuous external gills. Larvae can be censused at a convenient time at night during July. The best method for censusing salamander larvae is to slowly wade through the water shining a bright light on the surface. A bright light makes the larvae easier to see than trying to count them during the day.

Young-of-the-Year

Because newly transformed salamanders will likely quickly disperse from the breeding pond it is unlikely that a young-of-the-year census would be worthwhile and therefore, for salamanders at least, efforts should be concentrated on the larval stage.