Home ranges and movements of Egyptian Vultures Neophron percnopterus in relation to rubbish dumps in Oman and the Horn of Africa

Figures & data

Table 1. Details of satellite radio tags fitted to non-breeding Egyptian Vultures in Oman and the Horn of Africa.

Bird ID	Tag supplier	Tag Type	Data collection rate	Date deployed	Location	Age of bird at capture	Fate
EV1	Northstar	40 g GPS-Argos	Every 3 hrs	11 March 2013	Near Tadjore, Djibouti	4th plumage	Intermittent transmissions after May 2014. Bird apparently alive June 2018.
EV2	Geotrak	40 g GPS-Argos	Every 3 hrs	9 Jan 2015	Near Muscat, Oman	1st plumage	Died. Electrocution. 13 December 2015.
EV3	Aquila	33 g GPS-GSM	Every hour during daylight	21 Jan 2016	Near Muscat, Oman	1st plumage	Weeks-long gaps in data after April 2017, seemingly because bird spends too little time in GSM network for data upload. Last transmission 4 October 2017
EV4	Geotrak	40 g GPS-Argos	Every 3 hrs	10 Jan 2016	Near Muscat, Oman	1st plumage	Unknown fate. Transmissions stopped abruptly. 4 February 2016.
EV5	Aquila	33 g GPS-GSM	Every hour during daylight	19 Jan 2016	Near Muscat, Oman	1st plumage	Died. Near human habitation, unknown cause. 25 February 2016.

Figure 1. Locations (3-hourly), and 95%, 75%, and 50% KDE home ranges for (A) Horn of Africa vulture EV1; (B) Oman vulture EV2; and (C) Oman vulture EV3. See Table 1 for detailed information on the individual vultures.

Figure 2. Average 3-hour step-lengths throughout the diel period for the Egyptian Vultures tracked during this study: (A) Horn of Africa vulture EV1, (B) Oman vulture EV2, and (C) Oman vulture EV3. See Table 1 for details regarding the individual vulture.

Figure 3. Mean squared displacement (MSD) for Egyptian Vultures tracked during this study: (A) Horn of Africa vulture EV1, (B) Oman vulture EV2, and (C) Oman vulture EV3. See Table 1 for details regarding the individual vulture.

Table 2. Home range sizes in km² for non-breeding Egyptian Vultures captured in Djibouti (N = 1) and Oman (N = 2) at different contours, based on the Kernel Density Estimator (KDE) and on Minimum Convex Polygon (MCP).

Capture Location	ID	Fix interval	Number of locations	Bandwidth (h)	95% KDE	75% KDE	50% KDE	100% MCP	95% MCP	75% MCP	50% MCP
Djibouti	EV1	3 hours	2492	4587.82	5928.21	2455.19	859.86	20243.83	17889.24	17516.6	12023.15
Oman	EV2	3 hours	2217	4587.82	6846.01	2290.15	879.62	12637.04	6618.85	1956.29	952.39
Oman	EV3	3 hours	2709	4587.82	4238.47	1373.29	619.93	18599.63	12352.63	115719.6	5719.88
Oman	EV3	1 hour	5318	4565.43	7323.73	2471.16	924.23	21291.12	12443.37	11214.72	6884.5

Note: All estimates are based on fixes that were obtained every 3 hours, the average 3-hour step-length from all 3 vultures was used for the bandwidth (h). For the KDE estimates for vulture EV3 at the hourly scale, the ad hoc reference bandwidth was used.

Figure 4. Locations (3-hourly), and the number of revisits to the most frequently visited locations (circles) and dump sites (squares) by (A) the Horn of Africa vulture EV1; (B) Oman vulture EV2; and (C) Oman vulture EV3. See Table 1 for detailed information on the individual vultures and Table 3 for detailed information on residence times to the most visited dump sites.

Table 3. Average residence times and average times between visits to dump sites in Oman by non-breeding Egyptian Vultures (A) EV2 and (B) EV3 at their respective 5 most-visited dump sites.

	Name of Dump site	Governorate	Vulture Revisits	Average residence time ± se in hours (Range)	Average time between visits ± se in hours (Range)
A)
1	Al Maltaqa	Muscat	79	17.6 ± 1.59 (0.02, 67.34)	85.58 ± 35.04 (0.23, 2504.53)
2	Quriyat	Muscat	52	17.07 ± 1.16 (0.72, 45.18)	129.37 ± 69.71 (0.29, 3020.15)
3	Naffa	Dakhiliya	8	3.77 ± 0.44 (2.28, 5.84)	64.64 ± 41.14 (17.96, 310.37)
4	Sawaqim	Muscat	5	2.7 ± 1.11 (0.04, 5.95)	242.37 ± 182.79 (17.94, 788.75)
5	Al Amerat	Muscat	5	5.33 ± 3.19 (1.35, 18.03)	1223.73 ± 610.22 (69.56, 2468.94)
B)
1	Tahwa	Sharqiya South	86	14.1 ± 1.74 (0.87, 79.03)	152.01 ± 75.19 (1.26, 4638.42)
2	Al Hamar	Sharqiya North	69	17.86 ± 1.6 (0.07, 71.22)	156.92 ± 79.85 (0.24, 4000.93)
3	Al Maltaqa	Muscat	60	6.99 ± 0.89 (0.04, 30.14)	202.79 ± 66.37 (0.69, 2543.43)
4	Wadi Bani Jaaber	Sharqiya South	18	9.96 ± 1.11 (0.8, 19.93)	526.36 ± 505.67 (3.19, 8616.81)
5	Quriyat	Muscat	10	23.58 ± 11.15 (1.21, 115.38)	802.9 ± 400.38 (1.82, 3509.88)

Table 4. Mean 11-month home range sizes (km²) for Egyptian Vultures tracked by us compared to published mean winter home range sizes of Egyptian Vultures from migratory Eurasian populations.

Location	N	Age of birds	95% KDE	50% KDE	100% MCP
Ethiopia-Djibouti^a	1	Subadult-young adult (4th plumage)	5928	859	20243
Oman^a	2	Juveniles	5542	749	15618
Mali-Mauritania^b	2	Juveniles	–	–	44960
Mali-Mauritania^c	6	Breeding adults			48107**
Mauritania-Mali-Senegal^d	3	Breeding adults	20742	–	–
Yemen to Nigeria^e	9	Juveniles	211777	27137	310180
Ethiopia-Djibouti^f	14	Subadults/non-breeding adults	4950***	–	–

*Six individuals tracked during 2–5 winters, 19 vulture-winters; **(range: 8827–166678).

**Estimated using dynamic Brownian bridge movement model.

^aThis study.

^bMeyburg et al. (2004).

^cLópez-López et al. (2013).

^dGarcía-Ripollés et al. (2010).

^eOppel et al. (2015).

^fBuechley et al. (2018a).

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