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The biodiversity of native species is diminishing in many regions as natural habitats are being replaced by human settlements and agriculture. Top predators, such as large raptors, are especially sensitive to habitat change, and they present flagship species due to the interest in them by the public. By protecting the raptors' habitats we also protect other species that reside within these habitats. A large population of Short-toed Eagles (Circaetus gallicus, hereafter StE) were studied in the Judea region of Israel across a 1,175 km2 study site during the 2006-2008 breeding seasons, in order to determine whether the different types of habitat affect the number of successful breeding pairs. During the three-year study, we recorded 288 breeding attempts by StE pairs in 156 different nests located mainly on trees. Of the successful StE pairs, 76.9% bred in natural habitats while fewer pairs than expected bred in agricultural areas and human settlements. The mean number of successful StE pairs was positively related to the proportion of natural habitat types and negatively related to the proportion of human settlements and agriculture. Compared to successful pairs breeding in grids with a low density of StE, grids with higher breeding densities of successful pairs comprised more natural habitat types and less agricultural land and human settlement. Even though the population of StE in Israel is large, its future may be at risk as natural habitats are increasingly being destroyed and replaced by human settlements and agriculture. Conservation programs are therefore needed in order to protect as much natural habitat types as possible prior to urban planning and realisation. [ABSTRACT FROM AUTHOR]

The Ethiopian Bush-crow is an endemic Ethiopian bird species which has a very small and climatically distinct range that is cooler, dryer and more seasonal than the surrounding areas. Bush-crows build large domed nests made of thorny twigs with comparatively thick walls and a soil-lined bottom. In our preliminary study, we studied the thermal properties of a bush-crow nest with the aid of IR thermography. Our results show that there was no heat emission in the early morning and that nest surface temperatures clearly corresponded to the temperature changes during the day. Therefore we hypothesise that the nest construction provides substantial thermal insulation during the night time and presumably also delays temperature increase in the internal nesting chamber during the day time. We suggest that the bush-crow's specific nest construction may have contributed to its persistence under the climatically unique south Ethiopian conditions. [ABSTRACT FROM AUTHOR]