Conservation Evidence strives to be as useful to conservationists as possible. Please take our survey to help the team improve our resource.

Providing evidence to improve practice

Individual 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


This study is summarised as evidence for the intervention(s) shown on the right. The icon shows which synopsis it is relevant to.

Use shelterwood harvesting instead of clearcutting Amphibian Conservation

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.

 

Harvest groups of trees instead of clearcutting Amphibian Conservation

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.

 

Thin trees within forests Amphibian Conservation

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.