Year-round spatiotemporal distribution pattern of a threatened sea duck species breeding on Kolguev Island, south-eastern Barents Sea

Table 1 Phenology of the stages of the annual cycle of female long-tailed ducks breeding on Kolguev Island, derived from one year of geolocator data between Summer 2017 and Summer 2018

Characteristic of life stage event	Mean ± SD	Range	n
Longitude late breeding stage 2017	49 ± 1° E	47–50° E	19
Timeframe post-moult stage
Start	12 Sep. ± 11 days	29 Aug.–07 Oct.	19
End	15 Oct. ± 9 days	28 Sep.–01 Nov.	19
Duration post-moult stage	33 ± 10 days	19–50 days	19
Longitude post-moult stage	49 ± 4° E	37–56° E	19
Duration autumn migration	3 ± 3 days	0–11 days	19
Estimated distance autumn migration	1247 ± 320 km	519–1880 km	19
Timeframe wintering stage
Start	17 Oct. ± 7 days	02 Oct.–01 Nov.	19
End	17 May ± 5 days	10 May–02 June	17
Duration wintering stage	212 ± 3 days	197–229 days	17
Longitude wintering stage	21 ± 4° E	15–35° E	19
Latitude wintering stage	59 ± 2° N	56–66° N	19
Duration spring migration^a	2 ± 2 days	1–9 days	17
Estimated distance spring migration^a	1273 ± 307 km	549–1713 km	15
Timeframe pre-breeding stage
Start^a	20 May ± 5 days	14 May–03 June	17
End	12 June ± 9 days	01 June–02 July	17
Duration pre-breeding stage^a	23 ± 7 days	13–34 days	17
Longitude pre-breeding stage^a	46 ± 6° E	33–55° E	17
Longitude early breeding stage 2018^a	46 ± 3° E	37–50° E	17
Duration breeding stage (estimated)	91 ± 13 days	68–120 days	17

The estimates of migration distance are based on locations, modelled with probGLS
^aLongitudes and separation of life stages estimated from light curves of 24 h daylight

ISSN: 1472-6785