Converting predation cues into conservation management tools: The effect of light on Mus musculus behaviour (#24)
Prey species face a
conflict between acquiring energy and avoiding predators and use both direct
and indirect predation cues to assess predation risk. One indirect cue is
illumination, which affects nocturnal rodent foraging behaviour. In New Zealand
and other island ecosystems (e.g. Hawaii) rodents are introduced pests which
can have serious consequences on native biodiversity. We assessed if artificial
manipulations of light could limit the activity of pest mice (Mus musculus)
through inducing risk avoidance behaviour. We assessed Giving-Up Densities
(GUDs) and observed foraging frequency and duration to determine if captive
mice in outdoor pens had a preference for foraging under illuminated or dark
conditions. We then used GUDs at a pest fenced sanctuary (Maungatautari, New
Zealand) to determine the effect illumination had on foraging behaviour of wild
mice. Both captive and wild
mice exhibited avoidance behaviour in response to artificial illumination and
removed less seeds from illuminated seed trays. Captive mice spent less than
1.0% of their available time at illuminated sites; visited the lit seed tray less
than half as often as the unlit tray; and spent five times less time per visit
at the illuminated site. Illumination could be
useful for protecting nesting sites, deterring mice from damaged exclusion
fences until repair, preventing reinvasion at fence terminus zones of peninsula
sanctuaries and minimising unwanted immigration to ecologically intact offshore
islands. Possible limitations of illumination include pests habituating to the
stimulus, attraction of other unwanted pests such as stoats (Mustela
erminea), and unwelcome impacts on valued non-target native species.