Study

Meta-analysis of the effects of canopy removal on terrestrial salamander populations in North America

  • Published source details Tilghman J.M., Ramee S.W. & Marsh D.M. (2012) Meta-analysis of the effects of canopy removal on terrestrial salamander populations in North America. Biological Conservation, 152, 1-9.

Actions

This study is summarised as evidence for the following.

Action Category

Use shelterwood harvesting instead of clearcutting

Action Link
Amphibian Conservation

Harvest groups of trees instead of clearcutting

Action Link
Amphibian Conservation

Thin trees within forests

Action Link
Amphibian Conservation
  1. Use shelterwood harvesting instead of clearcutting

    A meta-analysis of the effects of different harvest practices on terrestrial salamanders in North America (Tilghman, Ramee & Marsh 2012) found that partial harvest, that included shelterwood harvesting, thinning and cutting individual or groups of trees resulted in smaller reductions in salamander populations than clearcutting. Overall, partial harvest produced declines 24% smaller than clearcutting. Average reductions in populations were lower following partial harvest (all studies: 31–48%; < 5 years monitoring: 51%; > 10 years monitoring: 29%) compared to clearcutting (all: 54–58%; < 5 years: 62%; > 10 years: 50%). There was no significant effect of the proportion of canopy removed in partial harvests. Sampling methodology influenced perceived effects of harvest. Salamander numbers almost always declined following timber removal, but populations were never lost and tended to increase as forests regenerated. Twenty-four site comparison and before-and-after studies that compared salamander abundance in harvested (partial or clearcut) and unharvested areas were analysed. Abundance measures included counts, population indices and density estimates.

     

  2. Harvest groups of trees instead of clearcutting

    A meta-analysis of the effects of different harvest practices on terrestrial salamanders in North America (Tilghman, Ramee & Marsh 2012) found that partial harvest, which included harvesting groups or individual trees, thinning and shelterwood harvesting, resulted in smaller reductions in salamander populations than clearcutting. Overall, partial harvest produced declines 24% smaller than clearcutting. Average reductions in populations were lower following partial harvest (all studies: 31–48%; < 5 years monitoring: 51%; > 10 years monitoring: 29%) compared to clearcutting (all: 54–58%; < 5 years: 62%; > 10 years: 50%). There was no significant effect of the proportion of canopy removed in partial harvests. Sampling methodology influenced perceived effects of harvest. Salamander numbers almost always declined following timber removal, but populations were never lost and tended to increase as forests regenerated. Twenty-four site comparison and before-and-after studies that compared salamander abundance in harvested (partial or clearcut) and unharvested areas were analysed. Abundance measures included counts, population indices and density estimates.

     

  3. Thin trees within forests

    A meta-analysis of the effects of different harvest practices on terrestrial salamanders in North America (Tilghman, Ramee & Marsh 2012) found that partial harvest, including thinning, cutting individual or groups of trees and shelterwood harvesting, decreased salamander populations, but less so than clearcutting. Reductions in populations were lower following partial harvest (all studies: 31–48%; < 5 years monitoring: 51%; > 10 years monitoring: 29%) compared to clearcutting (all: 54–58%; < 5 years: 62%; > 10 years: 50%). There was no significant effect of the proportion of canopy removed in partial harvests. Sampling methodology influenced perceived effects of harvest. Salamander numbers almost always declined following timber removal, but populations were never lost and tended to increase as forests regenerated. Studies that compared salamander abundance in harvested (partial or clearcut) and unharvested areas were identified. Twenty-four site comparison and before-and-after studies were analysed. Abundance measures included counts, population indices and density estimates.

     

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