Cranes soar on thermal updrafts behind cold fronts as they migrate across the sea

Thermal soaring conditions above the sea have long been assumed absent or too weak for terrestrial migrating birds, forcing large obligate soarers to take long detours and avoid sea crossing, and facultative soarers to cross exclusively by costly flapping flight. Thus, while atmospheric convection does develop at sea and is utilized by some seabirds, it has been largely ignored in avian migration research. Here we provide direct evidence for routine thermal soaring over open sea in the common crane, the heaviest facultative soarer known among terrestrial migrating birds. Using high-resolution biologging from 44 cranes tracked across their transcontinental migration over 4 years, we show that soaring characteristics and performance were no different over sea than over land in mid-latitudes. Sea-soaring occurred predominantly in autumn when large water-air temperature difference followed mid-latitude cyclones. Our findings challenge a fundamental paradigm in avian migration research and s..., , , # Cranes soar on thermal updrafts behind cold fronts as they migrate across the sea

This dataset and accompanying R scripts pertain to the research study on crane migration above the sea. The focus of this study is to analyze the migratory patterns of cranes, particularly their utilization of thermal updrafts and soaring-gliding dynamics during sea crossing. The dataset includes high-resolution GPS and accelerometer data, annotated with environmental variables, and the R scripts are tailored for statistical analysis and visualization of these data.

## Description of the data and file structure

The data folder contains the following files:

**1HzGPS_and_ACC_annotated (multiple files):**

* 1Hz data for individual cranes, annotated with environmental variables.
* File names include individual crane IDs.

**ThermalStats.csv:**

* Summarizes 10-minute segments with and without thermal activity.
* Used in `ThermalSections_analysis&plot.R` and `time_scales_analysis.R`.

**Soa...