Bird population declines and species turnover are changing the acoustic properties of spring soundscapes.

Natural sounds, and bird song in particular, play a key role in building and maintaining our connection with nature, but widespread declines in bird populations mean that the acoustic properties of natural soundscapes may be changing. Using data-driven reconstructions of soundscapes in lieu of historical recordings, here we quantify changes in soundscape characteristics at more than 200,000 sites across North America and Europe. We integrate citizen science bird monitoring data with recordings of individual species to reveal a pervasive loss of acoustic diversity and intensity of soundscapes across both continents over the past 25 years, driven by changes in species richness and abundance. These results suggest that one of the fundamental pathways through which humans engage with nature is in chronic decline, with potentially widespread implications for human health and well-being.

Effects of Natura 2000 on nontarget bird and butterfly species based on citizen science data.

The European Union's Natura 2000 (N2000) is among the largest international networks of protected areas. One of its aims is to secure the status of a predetermined set of (targeted) bird and butterfly species. However, nontarget species may also benefit from N2000. We evaluated how the terrestrial component of this network affects the abundance of nontargeted, more common bird and butterfly species based on data from long-term volunteer-based monitoring programs in 9602 sites for birds and 2001 sites for butterflies. In almost half of the 155 bird species assessed, and particularly among woodland specialists, abundance increased (slope estimates ranged from 0.101 [SD 0.042] to 3.51 [SD 1.30]) as the proportion of landscape covered by N2000 sites increased. This positive relationship existed for 27 of the 104 butterfly species (estimates ranged from 0.382 [SD 0.163] to 4.28 [SD 0.768]), although most butterflies were generalists. For most species, when land-cover covariates were accounted for these positive relationships were not evident, meaning land cover may be a determinant of positive effects of the N2000 network. The increase in abundance as N2000 coverage increased correlated with the specialization index for birds, but not for butterflies. Although the N2000 network supports high abundance of a large spectrum of species, the low number of specialist butterflies with a positive association with the N2000 network shows the need to improve the habitat quality of N2000 sites that could harbor open-land butterfly specialists. For a better understanding of the processes involved, we advocate for standardized collection of data at N2000 sites.

Efectos de Natura 2000 sobre las Especies No Focales de Aves y Mariposas con Base en Datos de Ciencia Ciudadana Resumen La red Natura 2000 (N2000) de la Unión Europea está entre las redes internacionales más grandes de áreas protegidas. Uno de sus objetivos es asegurar el estado de un conjunto predeterminado de especies de aves y mariposas (focales). Sin embargo, las especies no focales también pueden beneficiarse con la N2000. Evaluamos cómo el componente terrestre de esta red afecta la abundancia de las especies de aves y mariposas no focales más comunes con base en los datos de programas de monitoreo voluntario a largo plazo en 9,602 sitios para aves y en 2,001 sitios para mariposas. En casi la mitad de las 155 especies de aves evaluadas, particularmente entre aquellas especies especialistas en zonas boscosas, la abundancia incrementó (los estimaciones de la pendiente variaron desde 0.101 [DS 0.042] hasta 3.51 [DS 1.30]) conforme incrementó la proporción del paisaje cubierto por sitios de la N2000. Esta relación positiva existió en 27 de las 104 especies de mariposas (con una variación de estimaciones desde 0.382 [DS 0.163] hasta 4.28 [DS 0.768]), aunque la mayoría de las especies de mariposas fueron generalistas. Cuando se consideraron las covarianzas de cobertura de suelo estas relaciones positivas no fueron evidentes para la mayoría de las especies, lo que significa que la cobertura de suelo puede ser una determinante de los efectos positivos de la red N2000. El incremento en la abundancia conforme aumentó la cobertura de la N2000 estuvo correlacionado con el índice de especialización de las aves, pero no el de las mariposas. Aunque la red N2000 sostiene la abundancia alta de un espectro amplio de especies, el bajo número de mariposas especialistas con una asociación positiva a la red N2000 demuestra la necesidad de mejorar la calidad del hábitat de los sitios N2000 que podrían albergar a mariposas especialistas de campo abierto. Para un mejor entendimiento de los procesos involucrados, promovemos una recolección estandarizada de datos en los sitios de la red N2000.

Typicality of objects in urban park scenes.

Typicality is a basic property of any categorization process, including the categorization of environmental scenes. We tried to judge whether a scene as a type of situation influences judgements about the typicality of elements when considering the part-whole relationship between the element and the scene. The subjects were asked to rate typicality on a scale of 1 to 7 and to give a word that defined the urban park elements appearing in a park scene or on a blank background. Some elements (wastepaper basket, fountain, street lamp, and statue) were depicted with two styles (classical and contemporary). The results indicate that the scene or blank background had no effect on the typicality scores but subjects had difficulty providing an appropriate word when elements with a contemporary style were shown on a blank background.

P-SPACE: a program for simulating spatial behavior in small groups.

P-SPACE is a computer program that simulates spatial behavior in a small group of individuals. The program describes how interpersonal distances change through time as a result of changes in microlevel features, such as the minimization of local dissatisfaction. Agents are located in a two-dimensional lattice and can move some discrete space units at each discrete time unit within their neighborhood. A nonsymmetrical matrix of ideal distances between agents must be specified. Agents move in order to minimize their dissatisfaction, defined as a function of the discrepancy between possible future distances and ideal distances between agents. At each iteration, agents will move to those cells in their neighborhoods for which the function is minimized. Depending on the specific values in the ideal-distance matrix, different kinds of social dynamics can be simulated.

Measuring the typicality of objects included in environmental scenes: a logistic model for atypicality.

Some empirical studies have stated that people usually categorize scenes according to the suitability of their elements. This paper proposes a method of measuring the typicality of naturalistic objects contained in environmental scenes. 517 subjects gave a score of suitability for 110 object-scene pairs. We used a logistic model for the measurements which enabled us to obtain two indexes, atypicality and discrimination. Analysis showed that the objects could be arranged on a numerical scale according to their typicality in a scene, and from this we concluded that logistic models are a useful and powerful method of measuring typicality.