Experimental timelines with diagrams illustrating how feather sections reflect periods of the experiments.

<p>Feathers from experiment 1 were cut into three sections corresponding to periods prior to pre-enrichment (A), short-term enrichment (B), and removal of enrichment (C). The first feather from experiment 2 was cut into two sections corresponding to pre-enrichment (A) and short-term enrichment (B), and the second feather from experiment 2 was cut into three sections corresponding to long-term enrichment (C), removal of enrichment (D), and non-novel enrichment (E). See text for descriptions of time periods. Note: illustrations not to scale.</p

Mean (± SE) latency (sec) to feed (LTF) of nutcrackers during experiment 2.

<p>Filled circles: experimental birds; open circles: non-enriched controls. See text for explanation of time periods.</p

Mean (± SE) counts of nutcracker pecks (exploration, EXP) during experiment 2.

<p>Filled circles: experimental birds; open circles: non-enriched controls. See text for explanation of time periods.</p

Observation schedule for nutcracker behaviors during Experiment 2.

<p>Observation schedule for nutcracker behaviors recorded during Experiment 2. LTF = latency to feed, AL = activity level, EXP = exploration. See text for definitions of behaviors.</p>1<p>All behaviors were measured for 5 mins.</p

Mean (± SE) nutcracker feather CORT values (pg/mm) from experiment 2.

<p>Filled circles: experimental birds; open circles: non-enriched controls. (A) shows the first four time periods of the experiment; (B) shows the fifth time period (non-novel enrichment) and includes short-term (novel) enrichment for comparison. Note different scales on y-axes. See text for explanation of time periods.</p