Fig 1.
Study area (Extremadura rice fields; SW Spain) showing reservoirs, rice fields, main infrastructures and urban areas.
The asterisk indicate the reservoir (Gargáligas) used by northern pintails as roosting site during daylight.
Fig 2.
(A) Farmer ploughing a rice paddy after fall rains. Standing stubble is depicted in background, whereas in the foreground the paddy is ploughed and partly flooded with stubble incorporated into soil. (B) Flooded rice paddy with standing stubble; the stubble-free furrows created by the harvester are visible.
Fig 3.
Variation in the proportion of flooded area (rice paddies with and without standing stubble) through the winter season in a 20 km radius from the diurnal roosting area.
The total flooded area in late winter was a 75.1% lower than in early winter.
Fig 4.
Examples of nocturnal home-ranges of northern pintails overwintering at Extremadura rice fields.
Panels A and B: the Pint 06’s MCPs during the second week of December 2012 (1,312 ha; 96% of rice paddies were flooded and moonlight brightness 6%) and during the second week of January 2013 (4,082 ha; 39% of rice paddies were flooded and moonlight brightness 10%). Panels C and D: the Pint 05’s MCPs during the fourth week of January 2013 (4,765 ha; 45% of rice fields flooded and moonlight brightness 88%), and during the second week of January 2013 (2,637 ha; 39% of rice fields flooded and moonlight brightness 10%).
Table 1.
Summary of the GLM models explaining spatial use by northern pintails during night-time.
Table 2.
Summary of the GLM models explaining resource selection by northern pintails during night-time.
Table 3.
Estimates for the averaged resource selection model (RSF, using models within an Akaike accumulated weight ≤ 0.95) and relative importance of the parameters (RI).