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ENVIRONMENTAL CONSEQUENCES in rocky mountain coniferous ...

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<strong>in</strong>tact top broken top broken top <strong>in</strong>tact<br />

dead top<br />

SNAGS L lVE TREES<br />

<strong>in</strong>tact<br />

live top<br />

Figure 3.-- Five nest tree corzditions based on uhether tree is Zive or dead and<br />

cond;t$on of khe -bop.<br />

Woodpecker Feed<strong>in</strong>g Activity<br />

Each of the control (uncut) units and the cutt<strong>in</strong>g units <strong>in</strong> both the lower and<br />

higher units were observed for at least 60 hours (total for summer 1977 and spr<strong>in</strong>g<br />

and summer 1978). Feed<strong>in</strong>g woodpeckers were detected by visual and auditory cues.<br />

Once located, a bird was observed until it left the feed<strong>in</strong>g site. Bird species, feed-<br />

<strong>in</strong>g methods, total time the bird fed, feed<strong>in</strong>g substrate, substrate species, and sub-<br />

strate dbh were recorded. Observation time spent <strong>in</strong> each unit and its 4 subtreatments<br />

was divided between walk<strong>in</strong>g and stationary observation. As nearly as possible, equal<br />

time was devoted to each unit and subtreatment, dur<strong>in</strong>g similar weather conditions and<br />

hours of the day. The shelterwood units and the group selection units were observed<br />

from trails and routes through and around areas. Suitable vantage po<strong>in</strong>ts were chosen<br />

from which to view the clearcut units. In all units, if it was possible to hear or<br />

see feed<strong>in</strong>q birds <strong>in</strong> more than one subtreatment, the same observation time was record-<br />

ed for both. The total time each woodpecker species was observed feed<strong>in</strong>g <strong>in</strong> each unit<br />

and subtreatment with<strong>in</strong> a unit was calculated. Total feed<strong>in</strong>g times were then derived<br />

for species, unit, and subtreatment.

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