Freshwater Biodiversity Toolbox
Wildlife Passage – Culverts
Increasing habitat degradation and fragmentation has led to the installation of wildlife crossing structures such as culverts. Culverts are a common mitigation measure in reducing mortalities from road crossings and vehicular collisions for a variety of wildlife, including amphibians. They also seek to restore habitat connectivity for fish inhabiting anthropogenically altered and developed ecosystems. In many cases, culverts act as more of a physical or hydraulic barrier to wildlife depending the design and species being targeted. Therefore, more information is needed in order to properly assess both the potential ecological benefits and consequences of existing culvert structures, so that they may be better modified to species-specific movement patterns or removed altogether and replaced with more effective mitigation strategies.
Rating:
All papers for this intervention scored low in CEESAT demonstrating limitations in the rigour and the transparency in which these reviews were conducted (i.e., no a-priori protocol, critical appraisal, or search strategy provided). All but one synthesis was able to demonstrate some investigation of effect modifiers and six syntheses demonstrated some consideration of limitations.
Syntheses received mixed scores in RASCAT. High scores were given in elements related to habitat, latitude, environmental performance, and Polity scores of countries reviewed by syntheses. Many syntheses scored poorly with regards to publication year and the how relevant the climate and species reviewed were to a Canadian freshwater context.
Photo credit: Peter Van den Bossche
