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A universal challenge in methodology used to study the ecology, conservation and evolutionary biology of migratory species is the quantification of connectivity among breeding, wintering and stopover sites. For the avian Eurasian‐Afrotropical migratory system, knowledge of geographical wintering areas used by migrants that breed in Europe remains deficient, despite the advent of satellite transmitters and geolocators. Here we explored the use of theoretical plant δ13C and δ15N landscape distributions coupled with δ2H hydrologic models to construct multi‐isotopic avian foodweb clusters for Africa. The cluster analysis identified four distinct regions of Africa based on all three isotopes (13C, 2H, 15N), and five regions based only on 13C and 15N. We applied known isotopic diet‐tissue discrimination factors to map equivalent feather isotopic clusters for Africa. The validity of these feather isotopic clusters was tested by examining how well known‐ and unknown‐origin species were placed in regions of Africa using previously published feather isotope data. The success of this multi‐isotopic cluster model depended upon the species of interest and additionally on how well potential winter molt origins in Africa were constrained by prior information. Ground‐truthing data suggested this approach will be useful for first‐order approximation of overwintering regions for Afrotropical migrants and will be improved as our understanding of the nature of isoscapes for Africa is refined.

Temperature is a primary environmental control on ecological systems and processes at a range of spatial and temporal scales. The surface temperature of organisms is often more relevant for ecological processes than air temperature, which is much more commonly measured. Surface temperature influences-and is influenced by-a range of biological, physical, and chemical processes, providing a unique view of temperature effects on ecosystem function. Furthermore, surface temperatures vary markedly over a range of temporal and spatial scales and may diverge from air temperature by 40°C or more. Surface temperature measurements have been challenging due to sensor and computational limitations but are now feasible at high spatial and temporal resolutions using thermal imaging. Thus, significant advances in our understanding of plant and ecosystem thermal regimes and their functional consequences are now possible. Thermal measurements may be used to address many ecological questions, such as the thermal controls on plant and ecosystem metabolism and the impact of heat waves and drought. Further advances in this area will require interdisciplinary collaborations among practitioners in fields ranging from physiology to ecosystem ecology to remote sensing and geospatial analysis. In this overview, we demonstrate the feasibility, utility, and potential of thermal imaging for measuring vegetation surface temperatures across a range of scales and from measurement, analysis, and synthesis perspectives.

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