Prey resources are equally important as climatic conditions for predicting the distribution of a broad-ranged apex predator

Aim A current biogeographic paradigm states that climate regulates species distributions at continental scales and that biotic interactions are undetectable at coarse-grain extents. However, advances in spatial modelling show that incorporating food resource distributions are important for improving model predictions at large distribution scales. This is particularly relevant to understand the factors limiting distribution of widespread apex predators whose diets are likely to vary across their range. Location Neotropical Central and South America Methods The harpy eagle (Harpia harpyja) is a large raptor, whose diet is largely comprised of arboreal mammals, all with broad distributions across Neotropical lowland forest. Here, we used a hierarchical modelling approach to determine the relative importance of abiotic factors and prey resource distribution on harpy eagle range limits. Our hierarchical approach consisted of the following modelling sequence of explanatory variables: (a) abiotic covariates, (b) prey resource distributions predicted by an equivalent modelling for each prey, (c) the combination of (a) and (b), and (d) as in (c) but with prey resources considered as a single prediction equivalent to prey species richness. Results Incorporating prey distributions improved model predictions but using solely biotic covariates still resulted in a high performing model. In the Abiotic model, Climatic Moisture Index (CMI) was the most important predictor, contributing 76 % to model prediction. Three-toed sloth (Bradypus spp.) was the most important prey resource, contributing 64 % in a combined Abiotic-Biotic model, followed by CMI contributing 30 %. Harpy eagle distribution had high environmental overlap across all individual prey distributions, with highest coincidence through Central America, eastern Colombia, and across the Guiana Shield into northern Amazonia. Main conclusions With strong reliance on prey distributions across its range, harpy eagle conservation programs must therefore consider its most important food resources as a key element in the protection of this threatened raptor

Competition and habitat quality influence age and sex distribution in wintering rusty blackbirds.

Bird habitat quality is often inferred from species abundance measures during the breeding and non-breeding season and used for conservation management decisions. However, during the non-breeding season age and sex classes often occupy different habitats which suggest a need for more habitat-specific data. Rusty Blackbird (Euphagus carolinus) is a forested wetland specialist wintering in bottomland hardwood forests in the south-eastern U. S. and belongs to the most steeply declining songbirds in the U.S. Little information is available to support priority birds such as the Rusty Blackbird wintering in this threatened habitat. We assessed age and sex distribution and body condition of Rusty Blackbirds among the three major habitats used by this species in the Lower Mississippi Alluvial Valley and also measured food availability. Overall, pecan groves had the highest biomass mainly driven by the amount of nuts. Invertebrate biomass was highest in forests but contributed only a small percentage to overall biomass. Age and sex classes were unevenly distributed among habitats with adult males primarily occupying pecan groves containing the highest nut biomass, females being found in forests which had the lowest nut biomass and young males primarily staying in forest fragments along creeks which had intermediate nut biomass. Males were in better body condition than females and were in slightly better condition in pecan groves. The results suggest that adult males occupy the highest quality habitat and may competitively exclude the other age and sex classes

Anthropogenic noise is associated with changes in acoustic but not visual signals in red-winged blackbirds

Some birds in noisy areas produce songs with higher frequency and/or amplitude and altered timing compared to individuals in quiet areas. These changes may function to increase the efficacy of acoustic signals by reducing masking by noise. We collected audio recordings of red-winged blackbirds and measured noise levels. We found that males in noisier places produced songs with fewer syllables and slower repeat rate of elements in some components (rattles). Birds may also improve the efficacy of communication in noise by increasing usage of other signaling modalities. Red-winged blackbirds also perform a visual display in different intensities while singing. We also tested whether this species performs the visual display in different intensities according to current noise levels, and predicted that if the efficacy of songs is impaired in noisy places, males would compensate by performing a more intense visual display. For this, we also collected visual recordings from the same males from which we obtained acoustic recordings. We found no association between acoustic noise and the intensity of the visual display; thus, our results do not support the idea that males are using the visual display as a backup signal to communicate under acoustic noise. We discuss some possible explanations of this negative finding and for the observed noise-related changes in song length and rattle rate in the context of communication under noise

Towards an Advanced Acoustic Ecology

In the seventies, M.J. Schafer identified the first industrial revolution as a watershed that altered not only the soundscape (from lo-fi soundscape to hi-fi soundscape) but also the way it is perceived. The outcomes of this above-mentioned first industrial revolution created new sound conditions characterized by a continuous overlap that have affected the human being’s perception with negative effects on it, overturning what William Gaver defined “everyday sounds” (Schafer 1977). Forty-two years later we are experiencing the fourth industrial revolution that is affecting also the construction world (Schwab 2017). Robotics, artificial intelligence, nanotechnology, biotechnology, IoT, bespoke materials etc. are increasingly embedded within the new design approaches for the construction of sustainable architectures. Scientific speculation on this topic is such that we no longer speak of digital but of post-digital architecture. A phase in which the direct link between the digital and material (from bits to atoms) has shifted to the new relationship to neural system of the human being (from bits to neurons) (Carpo 2018). This new paradigm affects the way “objects” are designed and their way to influence modern soundscape. Base on this cultural background, the chapter intends to point out the framework of the research line “Advanced Acoustic ecology” developed on the base of a new approach of acoustic design: sound driven design