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Table 2 Density and population size

From: Guanaco abundance and monitoring in Southern Patagonia: distance sampling reveals substantially greater numbers than previously reported

Social unit Relative abundance Contacts g ( w ) Groups/km 2 D (ind/km 2 ) Lower limit Upper limit CV N
  Low 11 0.15 0.0431 0.4413 0.1289 1.5101 69.04 26,173
Medium 103 0.13 0.2249 2.3047 0.8001 6.6393 57.77 200,020
High 64 0.10 0.3455 3.5409 1.2066 10.3910 58.95 270,700
Breeding group Pooled 178 0.12 0.2179 2.2328 0.7839 6.3600 57.04 496,900
  Low 18 0.14 0.0347 0.3712 0.1792 0.7681 37.81 22,013
Medium 129 0.15 0.1413 1.5128 0.9988 2.2914 21.29 131,290
High 100 0.19 0.2656 2.8437 1.6483 4.9059 27.77 217,400
Non-breeding group Pooled 247 0.17 0.1556 1.6658 1.1253 2.4657 20.02 370,710
  Low 29 0.06   0.0814 0.0434 0.1643 36.72 4,828
Medium 159 0.05   0.2538 0.1495 0.4309 27.42 22,029
High 111 0.12   0.4297 0.2375 0.7774 30.76 32,849
Solitary individuals Pooled 299 0.08   0.2683 0.1595 0.4512 26.90 59,706
  Low 7 0.13 0.0396 0.0910 0.0201 0.4130 89.33 5,402
Medium 86 0.14 0.2766 0.6364 0.1479 2.7370 85.15 55,236
High 47 0.22 0.3665 0.8434 0.1964 3.6225 85.04 64,481
Undetermined Pooled 140 0.17 0.2443 0.5622 0.1328 2.3801 83.91 125,120
  Low 63 0.14 0.1920 1.1228 0.6663 1.8920 26.89 66,590
Medium 464 0.14 4.7028 4.7028 3.1082 7.1156 21.32 408,160
High 315 0.17 1.3236 7.7419 4.9303 12.1570 23.16 591,870
All contacts Pooled 842 0.15 0.8194 4.7928 3.2704 7.0240 19.65 1,066,600
  1. Estimates of guanaco density (D) and population size (N) for each observable social unit and in three classes of expected relative abundance of guanacos in Santa Cruz Province, southern Patagonia, during the 2004 and 2005 breeding seasons. The number of intervals used to fit the most parsimonious detection function was 10 in all cases. g(w) is the value of the detection function at the truncation distance (600 m for solitary guanacos, 500 m for other social units). Upper and lower limits of 95% confidence intervals for density estimates are reported. CV coefficient of variation of density estimates.