Table 4 in A comparison of image and observer based aerial surveys of narwhal

<p><i>Table 4.</i> Summary statistics of survey results and narwhal abundance estimates from surveys conducted in Melville Bay, West Greenland from 25 to 30 August 2014. Off-effort sightings by the aerial observers were only included in modeling of the detection function. Strata without narwhal sightings were excluded from this table (<i>i.e.</i>, south and northwest). Abundance estimates are corrected for availability bias with <i>&acirc;</i> (0) being 0.257 for the aerial observer sightings and 0.22 for the image sightings. Aerial observer sightings were truncated at 1,300 m. CV values are given in parentheses. Ind. = individuals.</p><table><tbody><tr><th></th><th></th><th></th><th></th><th></th><th>Uncorrected</th><th></th><th></th><th>Abundance</th></tr></tbody><tbody><tr><th></th><td></td><td></td><td>Encounter</td><td>Mean</td><td>density</td><td>Uncorrected</td><td>Uncorrected</td><td>of individuals</td></tr><tr><th>Platform</th><td>Stratum</td><td>Encounter rate (groups/km)</td><td>rate (ind./km)</td><td>group size</td><td>of groups (groups/km2)</td><td>density of ind. (ind./km2)</td><td>abundance of individuals</td><td>corrected for availability bias</td></tr><tr><th>Aerial</th><td>Northeast</td><td>0.032 (0.86)</td><td>0.084 (0.78)</td><td>2.6 (0.20)</td><td>0.046 (0.93)</td><td>0.115 (0.90)</td><td>300.7 (0.89)</td><td>1,171.0 (0.90)</td></tr><tr><th>observers</th><td>Central</td><td>0.068 (0.50)</td><td>0.261(0.53)</td><td>3.8 (0.11)</td><td>0.046 (0.53)</td><td>0.177 (0.52)</td><td>366.5 (0.52)</td><td>1,426.1 (0.53)</td></tr><tr><th></th><td>All strata</td><td>0.053 (0.41)</td><td>0.187(0.44)</td><td>3.5 (0.10)</td><td>0.046 (0.58)</td><td>0.142 (0.50)</td><td>667.2 (0.50)</td><td>2,596.1 (0.51)</td></tr><tr><th>Images</th><td>Northeast</td><td>0.049 (0.94)</td><td>0.105(0.92)</td><td>2.1 (0.91)</td><td>0.049 (0.94)</td><td>0.105 (0.92)</td><td>217.8 (0.92)</td><td>990 (0.93)</td></tr><tr><th></th><td>Central</td><td>0.059 (0.70)</td><td>0.130(0.61)</td><td>2.2 (0.71)</td><td>0.059 (0.70)</td><td>0.130 (0.61)</td><td>340.0 (0.61)</td><td>1,545.5 (0.61)</td></tr><tr><th></th><td>All strata</td><td>0.055 (0.55)</td><td>0.119(0.50)</td><td>2.2 (0.78)</td><td>0.055 (0.55)</td><td>0.119 (0.50)</td><td>557.8 (0.50)</td><td>2,535.5 (0.51)</td></tr></tbody></table>