Modelling the nesting-habitat of the Cinereous Vulture Aegypius monachus on a fine scale for conservation purposes

Figures & data

Figure 1. (a) The shaded area shows the location of Hornachuelos Natural Park in the region of Andalusia (southern Spain). (b) The black squares indicate the location of Cinereous Vulture nests in the study area, and the grey line is the limit of the Natural Park.

Table 1. Means (± se) of variables measured for the nests (n = 43) and the random points (n = 43).

Variables	Nest site	Random	U-test	P
Distance to roads (m)	4661 (±305)	3425 (±386)	806	<0.001
Distance to tracks (m)	124 (±16.8)	85 (±10.5)	1115	0.076
Distance to villages (m)	12 793 (±425)	10 520 (±476)	913	0.002
Altitude (m.a.s.l.)	339 (±10)	359 (±13)	1306	0.566
Slope (%)	37.4 (±1.8)	21.5 (±1.9)	570	<0.001
Distance to neighbour (m)	1031 (±141)	4893 (±486)	345	<0.001
Patch size (ha)	31 907 (±2196)	19 367 (±1817)	1011	0.010
Distance to edge patch (m)	340 (±45)	186 (±22.8)	919	0.003
Solar radiation (W/m^2)	536 068 (±1064)	571 933 (±5419)	1011	0.015
Q. suber (%)	14.7 (±1.12)	7.4 (±1.03)	14 776	<0.001
Q. rotundifolia (%)	14.6 (±1.67)	17.1 (±1.73)	1291.5	0.505
Pinus spp. (%)	9.5 (±2.57)	6.1 (±1.86)	1214	0.152

Table 2. Logistic regression models of Cinereous Vulture habitat requirements in Hornachuelos Natural Park.

	Model 1 ΔAICc = 4.08				Model 2 ΔAICc = 5.01
Parameter	Coefficient	Wald	df	P	Coefficient	Wald	df	P
Intercept	5.86 ± 2.58	5.15	4	0.023	−5.98 ± 1.31	20.7	4	<0.001
Ln nearest nest	−1.37 ± 0.34	16.26	4	<0.001	–	–	–	–
Slope	0.088 ± 0.023	14.58	4	<0.001	0.075 ± 0.019	16.21	4	<0.001
Distance to patch edge	0.003 ± 0.002	4.48	4	0.034	0.004 ± 0.001	9.61	4	0.002
Cork Oak cover	0.032 ± 0.028	1.35	4	0.035	0.058 ± 0.022	7.08	4	0.008
Distance to villages	–	–	–	–	0.001 ± 0.001	20.74	4	0.01

ΔAIC indicates the improvement in model fit of the final model compared with the next best model.

Figure 2. Probability of presence of Cinereous Vultures derived from logistic regression at a 50 × 50 m resolution taken into account the distance from the nearest nest (a) or without this variable (b).