Functional connectivity is essential for the long-term persistence of populations. However, many studies assess connectivity with a focus on structural connectivity only. Cityscapes, namely urban landscapes, are particularly dynamic and include numerous potential anthropogenic barriers to animal movements, such as roads, traffic or buildings. To assess and compare structural connectivity of habitats and functional connectivity of gene flow of an urban lizard, we here combined species distribution models (SDMs) with an individual-based landscape genetic optimization procedure. The most important environmental factors of the SDMs are structural diversity and substrate type, with high and medium levels of structural diversity as well as open and rocky/gravel substrates contributing most to structural connectivity. By contrast, water cover was the best model of all environmental factors following landscape genetic optimization. The river is thus a major barrier to gene flow, while of the typical anthropogenic factors only buildings showed an effect. Nonetheless, using SDMs as a basis for landscape genetic optimization provided the highest ranked model for functional connectivity. Optimizing SDMs in this way can provide a sound basis for models of gene flow of the cityscape, and elsewhere, while presence-only and presence-absence modelling approaches showed differences in performance. Additionally, interpretation of results based on SDM factor importance can be misleading, dictating more thorough analyses following optimization of SDMs. Such approaches can be adopted for management strategies, for example aiming to connect native common wall lizard populations or disconnect them from non-native introduced populations, which are currently spreading in many cities in Central Europe.

Facing increasing human demands on Earth, understanding how endangered species may survive in isolated remnants of natural habitat within heavily transformed landscapes is key to contemporary conservation biology. Against this background we here investigate the factors affecting pond occupancy in the endangered European tree frog (Hyla arborea L.) within an urban landscape, being located in north‐eastern Germany where the species is still fairly common. Our survey revealed that 58 out of 122 ponds were occupied by H. arborea. Ponds with a higher percentage of floating vegetation, being deeper and surrounded by higher percentages of crop fields and forests were more likely to be occupied, while factors associated with urbanization such as the percentage of built‐up area were strongly detrimental. Habitat requirements of H. arborea were complex as occurrence was simultaneously affected by different spatial scales, including the landscape scale, the immediate surroundings of ponds and the ponds themselves. H. arborea avoided highly urbanized areas, but occurred frequently in agricultural areas surrounding the city. The latter suggests that this species is fairly tolerant towards human‐induced transformations, and that vast arable fields yielded positive rather than negative effects on H. arborea occurrence. We conclude that the most important conservation issues for supporting H. arborea populations at the periphery of urbanized areas are (1) maintaining an open (agricultural) landscape structure, (2) providing undisturbed overwintering habitats, and (3) maintaining pond quality by halting shrub and tree encroachment.

The aim of this study was to investigate whether there are differences between particular characteristics of breathing regulation in primary hypertensive and normotensive states which might indicate significant differences in arterial chemoreceptor reflex function. Under air-breathing conditions, minute ventilation was similar in adult spontaneously hypertensive rats (SHR) (50 +/- 2ml/min x 100 g) and in Wistar-Kyoto rats (WKY) (54 +/- 3 ml/min x 100 g) but significantly lower in randomly bred normotensive Wistar rats (NWR) (39 +/- 1 ml/min x 100 g). In seven-day-old rats minute ventilation was 10.5 +/- 1.2ml/min x 10 g in SHR and 10.2 +/- 1.4 ml/min x 10 g in WKY. Our data indicate that there is no elevation of the ventilatory drive under air-breathing conditions which can be unequivocally associated with primary hypertension in adult and neonatal animals. Acute inhibition of ventilation caused by hyperoxia indicated that oxygen dependent peripheral chemoreceptor activity during air-breathing was similar in SHR and normotensive controls both in the unanesthetized neonatal state and in anesthetized adult animals. No well defined association between the characteristics of the hypoxic ventilatory response and primary hypertension could be demonstrated although responses in adult anesthetized SHR tended to be faster and of higher amplitude than in normotensive controls.