| Title | Artificial lighting triggers the presence of urban spiders and their webs on historical buildings |
| Abstract | Different spider species living in the urban environment spin their webs on building facades. Due to air pollution, web aggregations entrap dirt particles over time, assuming a brownish-greyish colouration and thus determining an aesthetic impact on buildings and street furniture. In Europe, the most common species causing such an aesthetic nuisance is Brigittea civica (Lucas) (Dictynidae). In spite of the socio-economical relevance of the problem, the ecological factors driving the proliferation of this species in the urban environment are poorly described and the effectiveness of potential cleaning activities has never been discussed in scientific literature. Over one year, we studied the environmental drivers of B. civica webs in the arcades of the historical down-town district of Turin (NW-Italy). We selected a number of sampling plots on arcade ceilings and we estimated the density of B. civica webs by means of digital image analysis. In parallel, we collected information on a number of potential explanatory variables driving the arcade colonization, namely artificial lighting at night, substrate temperature, distance from the main artificial light sources and distance from the direr. Regression analysis showed that the coverage of spider webs increased significantly at plots with higher light intensity, with a major effect related to the presence of historical lampposts with incandescent lamps rather than halogen lamps. We also detected a seasonal variation in the web coverage, with significant higher values in summer. Stemming from our results, we are able to suggest good practices for the containment of this phenomenon. |
| Source | Landscape and urban planning 180, pp. 187–194 |
| Keywords | Urban ecologyDigital image analysisLight pollutionAraneaeSynanthropic speciesAesthetic nuisance |
| Journal | Landscape and urban planning |
| Editor | Elsevier, New York, Paesi Bassi |
| Year | 2018 |
| Type | Articolo in rivista |
| DOI | 10.1016/j.landurbplan.2018.09.003 |
| Authors | Mammola, Stefano; Isaia, Marco; Demonte, Daniele; Triolo, Paolo; Nervo, Marco |
| Text | 412027 2018 10.1016/j.landurbplan.2018.09.003 ISI Web of Science WOS 000449896300020 Urban ecology Digital image analysis Light pollution Araneae Synanthropic species Aesthetic nuisance Artificial lighting triggers the presence of urban spiders and their webs on historical buildings Mammola, Stefano; Isaia, Marco; Demonte, Daniele; Triolo, Paolo; Nervo, Marco Fdn Ctr Conservaz Restauro Beni Culturali La Ve; Univ Turin Different spider species living in the urban environment spin their webs on building facades. Due to air pollution, web aggregations entrap dirt particles over time, assuming a brownish greyish colouration and thus determining an aesthetic impact on buildings and street furniture. In Europe, the most common species causing such an aesthetic nuisance is Brigittea civica Lucas Dictynidae . In spite of the socio economical relevance of the problem, the ecological factors driving the proliferation of this species in the urban environment are poorly described and the effectiveness of potential cleaning activities has never been discussed in scientific literature. Over one year, we studied the environmental drivers of B. civica webs in the arcades of the historical down town district of Turin NW Italy . We selected a number of sampling plots on arcade ceilings and we estimated the density of B. civica webs by means of digital image analysis. In parallel, we collected information on a number of potential explanatory variables driving the arcade colonization, namely artificial lighting at night, substrate temperature, distance from the main artificial light sources and distance from the direr. Regression analysis showed that the coverage of spider webs increased significantly at plots with higher light intensity, with a major effect related to the presence of historical lampposts with incandescent lamps rather than halogen lamps. We also detected a seasonal variation in the web coverage, with significant higher values in summer. Stemming from our results, we are able to suggest good practices for the containment of this phenomenon. 180 Published version Articolo in rivista Elsevier 0169 2046 Landscape and urban planning Landscape and urban planning Landsc. urban plan. Landscape and urban planning. stefano.mammola MAMMOLA STEFANO |
