Effects of reflective warning markers on wildlife

Abstract

Light pollution has become one of the top issues in environmental pollution, especially concerning how secondary light pollution, such as from traffic reflective materials, influences animal distribution and behavior. In this study, 15 camera traps were set up at sites with or without reflective warning markers (RWM) in coniferous forests on Cangshan Mountain located in Dali Prefecture, China. The results showed that the number of independent photographs and species at sites without RWMs were significantly higher than those at sites with RWMs. Significant differences were found between daytime and nighttime composition of bird species and non-flying mammals between two sites. This study found that RWMs had negative effects on wildlife, with the avoidance response of birds to RWMs being more obvious than that of animals at daytime. It is recommended that the use of reflective materials be carefully considered, especially in protected areas.

The effect of four different object properties on latency to approach in Goffin’s cockatoos (Cacatua goffiniana).

“…This lack of an effect may be partly due to the subtle differences between the objects used in this study. Reflective markings, such as those described by Fang et al (2019), entail much higher reflective capacities than the three spheres we ultimately used. We deliberately selected objects whose reflectance mimics the Plexiglass boxes regularly used for cognitive testing on this species in other experiments.…”

“…The objects used in this study were selected based on this species’ perception and ecology as recommended by Greggor et al (2015) and on hypotheses derived from previous habituation procedures to experimental apparatuses (see predictions in the introductory part). Previous studies have suggested that reflective surfaces may elicit avoidance in birds and mammals in the wild (Fang et al, 2019) and that removing reflective surfaces may increase welfare in captive cattle (Grandin, 2012). Testing for a neophobic response in this category may thus improve future enrichment programs for captive individuals of this species.…”

“…If object neophobia has intrinsic roots with ecological value, we would expect objects that resembled certain predator qualities (the larger objects in the size category, the elongated object in the shape category) to elicit stronger neophobic reactions than their corresponding control objects. As shiny apparatuses have been shown to produce long habituation times in some species (e.g., Fang et al, 2019) and some other avian species seem to react excitedly to red coloring (Healey et al, 2007; Pryke, 2009), we thus predicted neophobic reactions to shiny versus dull surfaces and a possible neophobic response toward red coloring. Each bird was confronted with 12 novel objects in a familiar testing room.…”