FORAGING TIME
100%
FORAGING METHOD
80% 60% 40% 20% 0% Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
FORAGING TIME
100%
FOOD ITEMS AT FORAGING SITES
80% 60% 40% 20% 0% Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
MONTH
Fig. 2.3. Pileated woodpecker foraging methods and food items at foraging substrates, by month, at Hinton, Alberta, 1993–96. Foraging methods were: (1) excavation into sapwood of hard (living trees, decay classes 1–4) substrates (grey shading); (2) excavation into sapwood of soft (decay classes 5–6) substrates (white shading); and (3) surface gleaning or excavation into bark (black shading). Decay classes were: (1) recently dead, wet inner bark, sap and foliage often present; (2) dry stem and bark, fine branches present, bark present and firmly attached; (3) mostly sound stem, fine branches gone, main branches present, bark variable; (4) few or no branches, softening stem, variable bark; (5) no branches, stem soft, bark mostly gone; and (6) stem shape intact, no branches, bark gone, stem very rotten. Food items at foraging sites were: (1) carpenter ants (grey shading); (2) other ant species (white shading); and (3) no visible food (black shading).
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