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Long-toed Salamander
Limiting Factors
Limiting factors for the Long-toed Salamander include those that affect habitat suitability, and reduce the survivorship of adults or larvae. Climate and access to low elevation passes for colonization may limit population size, however, the following discussion focuses on human impacts. Topics include
Coexistence with Predatory Fish, Human Disturbance and
Habitat Alteration.
Coexistence with Predatory
Fish: The presence of predatory fish may limit the distribution of Long-toed Salamanders on a local scale. Long-toed Salamander larvae can coexist with game fish, but coexistence depends upon a spatially complex habitat. Anecdotal evidence in Alberta strongly suggests a negative relationship between game fish and Long-toed Salamander numbers in the Front Range of the Rocky Mountains. Therefore, stocking of game fish in breeding ponds may affect Long-toed Salamander populations negatively.
Human Disturbance:
Human disturbance such as building roads that separate terrestrial habitat and breeding ponds has a limiting effect on populations. Collection of adults by the public while the salamanders are in or on their way to breeding ponds in the spring can also impact breeding population size. The long-term result of these actions on salamander populations is unknown.
Habitat Alteration:
Long-toed Salamander habitat may be impacted directly by forestry or mining activities or indirectly by agricultural chemicals. Populations of the Long-toed Salamander exist in areas with periodic habitat alterations associated with forestry and mining. However, it is unclear whether local extirpation with rapid recovery occurs in some of the populations or if Long-toed Salamanders are able to withstand these changes over the long-term. If local extirpation does occur, it is critical that source populations are present to recolonize recently disturbed habitats. The effect of pesticides, herbicides and other chemicals on Long-toed Salamander populations is unknown but could potentially have a detrimental impact on larvae and/or terrestrials. Long-toed Salamander larvae are sensitive to a combination of low pH and aluminum, and thus vulnerable to industrial activity that might produce such conditions in their breeding habitat.
Reprinted from Alberta Wildlife Status Report No. 22
(1999),
with permission from Alberta
Sustainable Resource Development.
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