Risk of Snake Entanglement Is Affected by Installation Method of Erosion Control Blankets

At the conclusion of road construction projects, an erosion control product (e.g., blankets, spray mulch) is installed to reduce soil loss and promote plant growth. Wildlife, such as snakes (suborder Serpentes), are prone to entanglement in erosion control blankets (ECBs) that contain polypropylene mesh with fused apertures. Previous reports have noted that the occurrences of entanglements are not uniform in their distribution across an ECB, but primarily occur where the edge of the mesh is exposed. We conducted an experiment to determine if modification to the installation methods of ECBs affects the likelihood of snake entanglement. We conducted entanglement trials to compare the likelihood of snake entanglement between two treatments: 1) exposed ECB edge (i.e., perimeter) and 2) buried ECB edge. Snakes were less likely to attempt to pass through the mesh on the buried edge treatment and all entanglements occurred on the exposed edge treatment. These results provide support that modification to the installation methods reduces snake entanglement in ECBs in some settings. However, we conducted our study in an experimental setting, and it should be evaluated under natural field conditions. This research can be used to inform several parties including contractors, habitat managers, and agency decision makers on additional steps that can be taken for products that fit their application needs to minimize risks to wildlife.