• Energy Research

Flying over the open sea is energetically costly for terrestrial birds. Despite this, over-water journeys of many birds, sometimes hundreds of kilometres long, are uncovered by bio-logging technology. To understand how these birds afford their flights over the open sea, we investigated the role of atmospheric conditions, specifically wind and uplift, in subsidizing over-water flight at a global scale. We first established that ΔT, the temperature difference between sea surface and air, is a meaningful proxy for uplift over water. Using this proxy, we showed that the spatio-temporal patterns of sea-crossing in terrestrial migratory birds are associated with favourable uplift conditions. We then analysed route selection over the open sea for five facultative soaring species, representative of all major migratory flyways. The birds maximized wind support when selecting their sea-crossing routes and selected greater uplift when suitable wind support was available. They also preferred routes with low long-term uncertainty in wind conditions. Our findings suggest that, in addition to wind, uplift may play a key role in the energy seascape for bird migration that in turn determines strategies and associated costs for birds crossing ecological barriers such as the open sea.

This dataset contains raster data (.TIF) in probability and binary outputs of oriental honey-buzzards distribution within the wintering and breeding areas under changing climate. File Size: ~184 MB (13.8 MB in compressed ZIP file) Format File: ohb_A_B_C.tif (.tfw; .XML; .dbf) A: breeding or wintering B: timepoint and scenario. e.g., 2050ssp5 or 2010ssp2 C: binary or probability outputs. e.g., bin or prob. Note: for binary maps, value 0: non-suitable areas for OHB and value 1: suitable areas for OHB For further inquiries. Please contact: aryo_acondro@apps.ipb.ac.id