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Trans‐Saharan migrants often spend a large proportion of their annual cycle wintering in the Sahel. Advances in fieldwork and tracking technology have greatly enhanced our ability to study their ecology in these areas. Using GPS‐tracking we aimed to investigate the little known non‐breeding movements of the lesser kestrel Falco naumanni in sub‐Saharan Africa. We segment non‐breeding tracks (n = 79 tracks by 54 individuals) into staging events (131 ± 25 days per non‐breeding cycle), itinerant movements between staging sites (11 ± 10 days), and non‐directed exploratory movements (6 ± 5 days). We then describe timing and directionality of itinerant movements by male and female kestrels throughout the non‐breeding season. Regardless of sex, lesser kestrels spent on average 89% of the non‐breeding season staging at two (range = 1–4) sites in West Africa. At the end of September, kestrels arrived along a broad front throughout the northern Sahel. By December, however, they congregated into two distinct clusters in Senegal and along the Malian–Mauritanian border. The birds stayed for longer periods and showed greater daily activity in the latter areas, compared to their first and intermediate ones. Among 24 individuals tracked along multiple annual cycles, 20 individuals consistently used the Senegalese or Malian–Mauritanian cluster. The remaining four birds either used these clusters in the 2nd or 3rd year of tracking or alternated between them across different years. The eastward and westward itinerant movements of lesser kestrels during the non‐breeding season, coupled with their tendency to cluster geographically towards the end, differ from the southward movements of other insectivorous raptors in West Africa. While 31% of Spanish lesser kestrels converged in Senegal, where roosts of > 20 000 birds are known, 68% moved into the Malian‐Mauritanian border region where more groundwork is needed. [ABSTRACT FROM AUTHOR]

[Display omitted] • Tropical lowland stream functioning was assessed through leaf litter decomposition. • Three litter types differing in their nativeness were examined. • Microbial decomposition was dominant across an agricultural intervention gradient. • Detritivore-mediated decomposition reflected the intervention gradient. • Microbial decomposition indicated differences among leaf litter types. Stream ecosystems are highly vulnerable to changes in land use and vegetation in their catchments for two reasons: firstly, they receive inputs of nutrients, contaminants and sediments through runoff; and secondly, terrestrial leaf litter is the major basal resource supporting their food webs. Leaf litter decomposition by microorganisms and detritivores is thus a key stream ecosystem process, and a valuable functional indicator of impacts associated to agriculture and other alterations of human origin. Here, we investigated the joint effects of land use changes associated to agriculture (low, medium and high intervention areas: LI, MI and HI, respectively) in a tropical lowland catchment in Panama, through a decomposition experiment using three leaf litter types differing in nativeness (Ficus insipida , native to the study area; Alnus acuminata , native to Panama but not present in the study area; and Musa balbisiana , exotic to Panama). Lowland tropical areas are often poor in litter-consuming detritivores, and we accordingly observed a high contribution of microorganisms to total decomposition (>60% on average). However, only in the presence of detritivores, decomposition of Alnus discriminated among different degrees of agricultural intervention, being higher at the LI area. Leaf litter of the native Ficus showed higher microbial decomposition than the other types, possibly in relation to a home-field advantage effect. Despite the scarcity of detritivores in tropical lowland streams compared to tropical highland or temperate streams, our study indicates that their activity reflects impacts of land use change on these streams and they should therefore be included in assessments of anthropogenic impacts. [ABSTRACT FROM AUTHOR]

Some results on rain height in relation to 0 °C isotherm height over three stations located in different geographical regions of tropical India at different latitudes are presented in this paper. The seasonal variation in rain height has been found to be appreciable over the stations located in the central plains (Nagpur) and the Kashmir region (Srinagar), while the seasonal variation is not significant over the station located on the south-west coast (Cochin). The distribution of 0 °C isotherm height over the different stations is also discussed on the basis of local weather conditions. The variation in ground temperature over Nagpur and Srinagar during the year is large, while the variation over Cochin is not significant. © 1998 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]