Mining morphometrics and age from past survey photographs

Table 1 Statistical results of Bland-Altman plots for each of 7 ratios measured, comparing the means and differences of morphometrics obtained from survey images to ‘gold standard’ measurements obtained in situ from darted elephants during collaring events. The lower and upper limit values indicate the limits of agreement (LOA). The percent error is calculated by dividing the limits of agreement by the mean value of the measurements. n = 12–15

Variable (ratio)	Mean differences	Lower limit			Upper limit
Variable (ratio)			Percent error	95% CI		Percent error	95% CI
Tusk length: body length	0.043	−0.025	− 0.58	− 0.058 – 0.008	0.111	2.58	0.078–0.144
Tusk length: body height	− 0.023	− 0.073	3.17	− 0.100 – − 0.046	0.027	−1.17	5.74 × 10^− 5 – 5.33 × 10^− 2
Tusk length: foot diameter	−0.301	− 0.707	2.35	− 0.936 – − 0.479	0.105	−0.349	− 0.122 – 0.335
Tusk length: tusk diameter	−1.020	−3.86	3.78	−5.11 – − 2.61	1.823	− 1.787	0.574–3.07
Tusk diameter: body length	0.011	0.004	0.364	9.31 × 10^− 4 – 0.080	0.018	1.636	0.015–0.022
Tusk diameter: body height	0.002	−0.005	− 2.50	− 0.009 – − 0.001	0.009	4.5	0.005–0.012
Tusk diameter: foot diameter	− 0.015	−0.077	5.13	−0.112 – − 0.042	0.047	− 3.13	0.012–0.082

ISSN: 1742-9994