For fast-flying birds, the ability to respond to wind during landing is critical, as errors can lead to injury or even death. Nonetheless, landing ability, and its ecological significance, remain unstudied. We show that for auks, 60% of attempts to land at their cliff nests fail in a strong breeze (80% in near-gale winds). This is most likely because wind interferes with the ability to maintain flight control in the last phase of landing. Their extreme flight costs mean that the energetic penalty for multiple landing attempts is high. We propose that exposure, and ability to respond to, such conditions will influence the suitability of breeding habitat. In support of this (i) auk colonies appear to be orientated away from prevailing winds and (ii) landing success within colonies is higher on crowded ledges with more airspace for manoeuvring. More generally, the interplay between wind and flight capacities could impact breeding distributions across species and scales.

Animal-attached technologies can be powerful means to quantify space-use and behaviour, however, there are also ethical implications associated with capturing and instrumenting animals. Furthermore, tagging approaches are not necessarily well-suited for examining the movements of multiple individuals within specific, local areas of interest. Here, we assess a method of quantifying animal space use based on a modified theodolite with an inbuilt laser rangefinder. Using a database of > 4,200 tracks of migrating birds, we show that detection distance increases with bird body mass (range 5 g - >10 kg). The maximum distance recorded to a bird was 5500 m and measurement error was ≤ 5 m for targets within this distance range; a level comparable to methods such as GPS tagging. We go on to present a case study where this method was used to assess habitat selection in seabirds operating in dynamic coastal waters close to a tidal turbine. Combining positional data with outputs from a hydrographic model revealed that great cormorants (Phalacrocorax carbo) appeared to be highly selective of current characteristics in space and time; exploiting areas where mean current speeds were < 0.8 m s , and diving at times when turbulent energy levels were low. These birds also orientated into tidal currents during dives. Taken together, this suggests that collision risks are low for cormorants at this site, as the two conditions avoided by cormorants (high mean current speeds and turbulence levels), are associated with operational tidal turbines. Overall, we suggest that this modified theodolite system is well-suited to the quantification of movement in small areas associated with particular development strategies, including sustainable energy devices. This article is protected by copyright. All rights reserved.

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Samples were taken weekly from 11 June to 1 October 1968 from brown slime fluxes occurring on trees (mostly elms) in Rockport, Mass., and in central and eastern areas of Connecticut and held in the laboratory for the emergence of adult insects.The most common emergents were Aulacigaster leucopeza (Meigen) and its parasite, Aphaereta colei Marsh, Mycetobia divergens (Walker), and Dasyhelea oppressa Thomsen. The only drosophilid reared from brown slime flux was Drosophila robusta Sturtevant, a species that was not particularly common.A comparison of the brown flux fauna of Great Britain with that of New England shows that some cosmopolitan species occur in flux in both countries. Species whose distribution is limited to only one of the countries are represented in the other country by closely related species (ecological homologues).The relationship between climatological factors and the fluxing condition of trees is discussed. The factor considered most important in continuing the fluxing state is rainfall during the late summer months.

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