DOI: 10.5061/dryad.47d7wm3jk
title: Autumn migration of black-necked cranes on the Qinghai-Tibetan and Yunnan-Guizhou Plateaus

description: Despite previous research efforts, the majority of migration routes of the
 black-necked cranes (Grus nigricollis) have remained veiled. In this
 study, we utilized satellite telemetry data from 45 cranes between 2015
 and 2021 to unveil critical insights. Our results revealed 11 distinct
 autumn migration routes and one sedentary flock, of which eight routes and
 the sedentary flock were previously undocumented. Our findings highlighted
 the remarkable diversity in the migration routes of black-necked cranes,
 especially in terms of migration orientations, spatial-temporal patterns,
 and altitudinal movement patterns. Cranes breeding on the eastern,
 northern, and central Qinghai-Tibetan Plateau migrated southward, while
 those on the northern slopes of the Himalayas migrated eastward, westward,
 northward, or opted to remain sedentary. Moreover, we expanded the known
 range of migration distances to 84–1,520 km at both ends (excluding
 sedentary individuals) and identified two long-term (Da Qaidam and Chaka)
 and one short-term (Gyatong grassland) stopover sites. Furthermore, our
 study revealed that the breeding colonies in the Qilian Mountains on the
 northeastern Qinghai-Tibetan Plateau utilized long-term stopover sites
 before embarking on significant altitude ascent, while other flocks
 displayed more urgent migration patterns, preferring to roost only at
 night. By unveiling the near-complete autumn migration routes of
 black-necked cranes, our research has contributed to discovering the
 critical habitats and connectivity among various breeding colonies, which
 is instrumental in developing effective seasonal conservation plans.
description: # Title of Dataset: Autumn Migration of Black-necked Crane (*Grus
 nigricollis*) on the Qinghai-Tibetan and Yunnan-Guizhou Plateaus ***
 Despite previous research efforts, the majority migration routes of the
 black-necked cranes (*Grus nigricollis*) have remained veiled. In this
 study, we utilized satellite telemetry data from 45 cranes between 2015
 and 2021 to unveil critical insights. Our results revealed 11 distinct
 autumn migration routes and one sedentary flock, of which eight routes and
 the sedentary flock were previously undocumented. Our findings highlighted
 the remarkable diversity in the migration routes of black-necked cranes,
 especially in terms of migration orientations, spatial-temporal patterns,
 and altitudinal movement patterns. ## Description of the Data and file
 structure Data were received hourly via the Global System for Mobile
 Communications/GSM (CMCC, China). The tracking data was classified into
 six accuracy grades: A (5 m), B (10 m), C (20 m), D (100 m), E (200 m),
 and invalid. We analyzed the data using locations categorized as A, B, C,
 and D. We calculated the migration distance, linear distance, and maximum
 step length via the great circle route using the “geosphere” and “move”
 packages in R v.4.2.1. The migration routes were mapped in QGIS v.3.24.1.
 We extracted the ground elevation using latitude and longitude data,
 calculated the average breeding elevation, average wintering elevation,
 and the elevation difference between breeding and wintering sites,
 andcompared the ground elevation of different routes in the migratory
 flight. The migration distance finished (%) for each point was calculated
 as the percentage of its respective migration distance to the overall
 migration distance. We plotted the ground elevation trends of different
 routes at the migration distance finished scales, using the
 smoothing-fitting method known as locally weighted regression (LOESS) from
 the ggplot2 package in R v.4.2.1.