Substrate preferences by the intertidal wood boring weevil Pselactus spadix (Herbst)

Substrate preferences by Pselactus spadix adults were investigated using tactile choice-tests employing beech (Fagus sylvatica L.) and Scots pine (Pinus sylvestris L.) blocks. These were drilled or undrilled, impregnated with seawater or distilled water, or conditioned to 11–16% moisture content, undecayed or decayed by Halosphaeria mediostetigera, Humicola alopallonella or Chaetomium globosum. Choice-tests showed significant preferences for pine over beech, for wood of high moisture content (irrespective of water type) and for drilled over undrilled blocks. Preferences for decayed blocks were only seen in those exposed to C. globosum, and for Scots pine decayed by H. mediostetigera. Adults were also found to be negatively phototactic.