Pileated Woodpeckers (Dryocopus pileatus) and Saproxylic Beetles in Partial Cut and Uncut Bottomland Hardwood Forests
Relative abundance and species richness of saproxylic beetles and nesting, roosting, and foraging ecology of pileated woodpeckers were studied in recent partial cuts and uncut forest during the summers of 2006 and 2007. Relative abundance of saproxylic beetles was greater in one-year old cuts than uncut forest during 2006 but was not consistent during 2007. The number of dead trees, period of capture, and trapping year also influenced beetle abundance. Species richness was similar in partial cuts and uncut forest.
Characteristics of habitat used by pileated woodpeckers for nesting and roosting in one-year-old and two-year-old partial cuts and uncut forest were similar. Woodpeckers used five species of trees that were between 42 and 150 cm diameter at breast height (dbh) for nesting (n = 24, 60.5 ± 3.02; mean ± SE) and roosting (n = 15, 70.3 ± 7.03). Baldcypress (Taxodium distichum) was selected in all treatments. Nests (22 of 24) and roosts (12 of 15) were predominantly in boles of live trees (vigorous to decadent). Nest and roost sites contained more trees >50 cm dbh than were available in random plots.
Foraging observations were conducted in 20 territories of radio- and non-radio-tagged pileated woodpeckers. Pileated woodpeckers spent the highest proportion of their foraging time excavating (58%), followed by pecking (14%), gleaning (14%), scaling (7%), berry-eating (4%), and probing (3%). They foraged on live boles (41%), dead branches (27%), live branches (13%), dead boles (10%), and vines (9%). Woodpeckers preferred bitter pecan (Carya aquatica), avoided sugarberry (Celtis laevigata), and used overcup oak (Quercus lyrata) in proportion to availability. They avoided dbh classes 10-20, selected dbh classes 50-70, and used dbh classes 30-40 in proportion to their availability in most treatments. In partial cuts, extremely large trees (dbh classes 80-90+) were selected. Pileateds either avoided vigorous and decadent trees for foraging or used them in proportion to their availability. Woodpeckers preferred trees in early stages of decay in all treatments but in two-year-old partial cuts they preferred trees in late stages of decay. Scat of pileated woodpeckers contained Pheidole ants, carpenter (Camponotus) ants, beetles (Coleoptera), and seeds of poison ivy.
Advisor:Sammy King; Phil Stouffer; Chris Carlton; Jing Wang
School:Louisiana State University in Shreveport
School Location:USA - Louisiana
Source Type:Master's Thesis
Keywords:renewable natural resources
Date of Publication:04/11/2008