Constructing urban ecological corridors to reflect local species diversity and conservation objectives.

Ensuring bird diversity can secure key ecosystem services within cities. Building ecological corridors into urban planning is an effective way to protect urban birds, but existing corridor construction methods often ignore locality and diversity of species, leading to homogenization of corridor construction results and orientation. We proposed a corridor construction model that combines local bird surveys and bird threat levels. After constructing differentiated corridors for each bird species by assessing their habits and flight abilities, we used three weighted scenarios (original, weighted abundance, weighted abundance, and phylogeny) to assess the conservation priorities of birds and overlaid them to derive a comprehensive bird corridor model. Our results show significant differences in conservation priority and corridor pattern among different bird species, thus demonstrating the importance of local bird surveys and knowledge of threat levels in accurate corridor simulations. This study provides differential simulation of corridors for each bird species and the identification of important conservation species, and uses these to extend the theory of ecological corridor planning to urban bird populations. These results can be applied to guide biodiversity management, evaluate green space policies, and provide practical assistance for sustainable urban development and management.

The call of the wild: Investigating the potential for ecoacoustic methods in mapping wilderness areas.

The critical importance of wilderness areas (WAs) for biodiversity conservation and human well-being is well established yet mapping criteria on which WA management policies are based take neither into account. Current WA mapping methods are framed in terms of absence of anthropogenic influence, and created using visual satellite data, obviating consideration of the ecological or anthropogenic value of WAs. In this paper we suggest that taking the acoustic environment into account could address this lacuna. We report the first investigation into the potential for ecoacoustic methods to complement existing geophysical approaches. Participatory walks, including in situ questionnaires and ecoacoustic surveys were carried out at points along transects traversing urban-wilderness gradients at four study sites in the Scottish Highlands and French Pyrenees. The relationships between a suite of six acoustic indices (AIs), wilderness classifications and human subjective ratings were examined. We observed significant differences between five out of six AIs tested across wilderness classes, demonstrating significant differences in the soundscape across urban-wild gradients. Strong, significant correlations between AIs, wilderness classes and human perceptions of wildness were observed, although magnitude and direction of correlations varied across sites. Finally, a compound acoustic index is shown to strongly predict mapped wildness classes (up to 95% variance explained MSE 0.22); perceived wilderness and biodiversity are even more strongly predicted. Together these results demonstrate that the acoustic environment varies significantly along urban-wild gradients; AIs reveal details of environmental variation excluded under current methods, and capture key facets of the human experience of wildness. An important next step is to ascertain the ecological and anthropogenic relevance of these differences, and develop new automated acoustic analysis methods suited to mapping the environmental characteristics of WAs. Taken together, our results suggest that future management of WAs could benefit from ecoacoustic methods to take the biosphere and anthroposphere into account.