Clearcut logging restricts the movements of terrestrial Pacific giant salamanders (Dicamptodon tenebrosus Good)

Abstract

Pacific giant salamanders (Dicamptodon tenebrosus Good) in the Chilliwack River valley of southwestern British Columbia are at the periphery of their range, and therefore of conservation concern. Although logging is a potential threat to the species, no studies have examined how clear-cutting affects its terrestrial stage. We used radio telemetry to compare the movements of 35 terrestrial Pacific giant salamanders at sites with three different logging histories: forested, clearcut to the stream margin, and clearcut with riparian buffer strips. The results demonstrate that logging affected movements of the salamanders. Salamanders in clearcuts remained significantly closer to the stream, spent more time in subterranean refuges, and had smaller home ranges than those at forested sites. During a dry year, salamanders in clearcuts were significantly more dependent on precipitation for their movement than salamanders in forested habitats. Salamander movement behavior in riparian buffer strips was not significantly different from that at forested sites but was significantly different from that at clearcut sites. Riparian buffer strips appear to mitigate some of the negative effects of clearcuts on salamander movement.

Taxocenose de anuros de uma mata semidecídua do interior do Estado de São Paulo e comparações com outras taxocenoses do estado, sudeste do Brasil

“…A fragmentação de hábitats e os desmatamentos são tidos como os principais responsáveis pela perda de diversidade e extinções locais de espécies de anuros em todo o mundo (Hitchings & Beebee 1997, Johnston & Frid 2002. Além dos efeitos diretos (perda de hábitat), a fragmentação prejudica a dispersão das espécies de anuros, levando a uma diminuição da abundância populacional e da riqueza de espécies em fragmentos isolados (Funk et al 2005) e permitindo que espécies generalistas ampliem suas distribuições podendo substituir populações nativas mais especializadas (Kats & Ferrer 2003).…”

Environmental and Anthropogenic Factors Influencing Salamanders in Riparian Forests: A Review

“…In southern Appalachian riparian forests, timber harvest can result in reduced leaf litter mass, depth, and moisture, and the elimination of canopy cover can increase soil temperature while decreasing surface soil moisture [111,121]. Timber harvest in Pacific Northwest riparian forests can increase stream temperatures, impacting cold-adapted stream amphibians, and restrict movement [65,122]. Clear-cut areas may also contain a lower percent cover of CWD and leaf litter [119].…”

“…Habitat management guidelines for salamanders should be incorporated into harvest operations. Some recommendations for managers of riparian forests to help maintain salamander populations include preserving logs and snags as moist microhabitats, retaining some understory to provide shade, and maintaining riparian buffer zones [122,131]. Partial harvest with limited canopy thinning may be a viable method to maintain salamander populations [126,132].…”

Buffer-Mediated Effects of Clearcutting on In-Pool Amphibian Productivity: Can Aquatic Processes Compensate for Terrestrial Habitat Disturbance?

“…Buffers effectively protect surface water quality and mitigate flooding [8][9][10]. In stream systems, where most manipulative buffer work has been conducted, riparian buffers have also been successfully used to mitigate the effects of clearcuts on multiple stream-dependent amphibian species (e.g., [11][12][13]). Considerably less research has focused on the wildlife value of buffers around lentic habitats [14,15].…”