Figure 1.
A year of longitude variations for Turtle Doves fitted with geolocators in 2009 (A–C) and 2010 (D–E).
Dots correspond to both noon and midnight locations in WGS84 degrees (twice smoothed). Key dates are indicated (see §Results, Tab. 1). The circled points correspond to the dates when longitude data indicated that birds were located either off the coasts of Portugal or over Moroccan/Mauritanian territories (see also Fig. 2 depicting migration pathways from that date). Data can be accessed at: doi:10.5061/dryad.bv24t.
Figure 2.
Estimated migration routes, stopover- and wintering areas of Turtles Doves with key dates.
Density contours reflect 50, 75, 90 and 95% kernel density. Dashed lines depict the migration corridor used by the birds in autumn, when longitude data indicated that they were clearly off the coasts of Portugal or over Moroccan or Mauritanian territories (See also Fig. 1). Wintering grounds are coloured red and are based on all locations (twice a day) outside the autumnal equinox period (from 12 Oct) and until departure date in the following spring. Staging areas are coloured green. Note that kernel contours do not illustrate home ranges because the inaccuracy of data is embedded in their calculation. The spring migration routes derived from (twice smoothed) positioning data are shown along with the corresponding dates for illustrative purposes. Note that single positions (black dots) and migration paths (dash lines) are approximated on the basis of geolocation data with low accuracy. The migration route for bird#5 that started its autumnal migration earlier is framed in box. Note that the location on 31 August was at the extreme bounds of the exclusion period (i.e. 31 Aug/12Oct.). Bird IDs are similar to Fig. 1 and Tab. 1. The loggers of birds #1 and 5 ceased collecting data en-route. Data can be accessed at: doi:10.5061/dryad.bv24t.
Table 1.
Detail of the migration schedule of the five Turtle doves equipped with geolocators in 2009 (birds #1–3) and 2010 (birds #4–5).
Table 2.
Detail of the migration schedule of the five Turtle doves equipped with geolocators (continued).