Barred owl detection probabilities by dog versus vocalization surveys.

<p>As per <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0042892#pone-0042892-g002" target="_blank">Figure 2a</a>, detection probabilities were derived from from occupancy models using data for all polygons sampled, after controlling for occupancy <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0042892#pone.0042892-MacKenzie1" target="_blank">[1]</a>. These probabilities also incorporate the mean CJ-habitat quality values from the sites (see text). The lines represent 1 SE.</p

Northern spotted owl and barred owl detections during dog and vocalization surveys per polygon.

<p>Red squares correspond to northern spotted owls and yellow squares correspond to barred owls. An owl inside the square indicates a dog detection, a sound wave illustration inside the square indicates a vocalization survey detection. A ? inside the square indicates a one-time DNA amplification from a pellet, which thus did not meet the criterion of two successive DNA amplifications to confirm a species. Blue circles represent pellets located by dogs that failed to amplify for mtDNA. Each polygon number is indicated in white inside the black square outlining the polygon. The thin black lines indicate dog survey routes. Habitat quality ranges from high (green) to intermediate (yellow) to low (brown) and were generated from the Zabel et al. <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0042892#pone.0042892-Zabel1" target="_blank">[16]</a> and Carroll and Johnson <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0042892#pone.0042892-Carroll1" target="_blank">[17]</a> habitat models. The two models are merged by making the coarse <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0042892#pone.0042892-Carroll1" target="_blank">[17]</a> model transparent and overlaying it on the more fine-grained model <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0042892#pone.0042892-Zabel1" target="_blank">[16]</a>. This collectively increases and decreases color contrast on the map when the two models concur or differ, respectively.</p

Distribution and percent of fecal samples successfully identified to sex and pod.

<p>Distribution and percent of fecal samples successfully identified to sex and pod.</p

Physiological stress correlates with year, Chinook availability, vessel abundance and an interaction between Chinook and vessel abundance.

<p>According to the best-fit mixed effects model, glucocorticoid concentrations decreased with increased Chinook salmon CPUE, after taking into account a 10-day lag time for fish to swim from the study site to the test fishery (column A). The best-fit model also includes an interaction between Chinook counts and vessel abundance on glucocorticoids, whereby fecal glucocortiods are always high at times of low Chinook counts. However, an increase in glucocorticoids with increasing vessel abundance is observed only during times of relatively high Chinook counts (column B set to the Chinook value indicated by the vertical line in the corresponding panel of column A). The y-axis represents glucocorticoid concentration marginal means predicted from the best-fit model. The hashed blue lines indicate 95% confidence intervals. Vertical red dotted lines indicate Julian day 230 (August 18), the time of maximum vessel traffic and approximately ten days before the maximum Chinook salmon catch each year. Horizontal red dotted lines indicate dependent variable marginal means for each year on day 230 within the model.</p