Investigating the Influence of Anthropogenic Activities on Behavioral Changes of an Orb Web Spider (Neoscona vigilans)

TL;DR

This study examines how road traffic affects the web-building behavior of Neoscona vigilans spiders, finding that proximity to roads increases web defects.

Contribution

The study provides empirical evidence of how anthropogenic disturbances, like road traffic, influence spider web construction behavior.

Findings

Web defects increased significantly closer to roads, indicating negative effects of traffic disturbance.

Spider body measurements correlated with web characteristics like size and mesh.

Anomalies like holes were most common in webs near roads, suggesting environmental stress.

Abstract

Spiders are considered natural polyphagous bio-control agents of agro-ecosystems and the best indicators of environmental health. They have the ability to adapt to different environments and are, therefore, present in almost all types of terrestrial ecosystems. The behavior of spiders is influenced by different biotic and abiotic factors, such as roadside disturbance, which may affect normal web-building behavior. Spiders, Neoscona vigilans, were captured, body measurements were taken, and their web characteristics along the road premises were calculated. Web characteristics had a significant association with spider body characteristics and also with the distance from the road, which changed gradually as the webs were constructed closer to the road. Road disturbance had a negative impact on normal web construction as more defects were observed in the webs constructed closer to the road, while dramatically more perfect webs were observed as the distance from the road increased. We concluded that disturbances such as roadside traffic had diverse effects on spider behavior. The outcomes of this study provide insight into the role of traffic on the livelihood of spiders encountering human-influenced disturbance in the ecosystem.

Orb web spiders are common and highly diversified animals found in almost all habitats. They have remarkable plasticity against biotic and abiotic factors, making them excellent indicators of environmental health. The web creation behavior of spiders is influenced by disturbances in the environment. The aim of this research was to observe the alteration in the web-building behavior of Neoscona vigilans caused by human activities, specifically traffic disturbances. Spider webs were located and photographed at nighttime along the roadside, and their web characteristics were calculated. Spiders were captured from webs for their body measurements. Spider fourth leg length, carapace width, and body length had a significant association with web size and diameter, CTL, capture area, and mesh size. The quantity of trapped prey, the height of the plant, and the foliage radius increased with the distance from the road. Conversely, anchor points and web elevation from the ground dropped. The highest and lowest proportions of anomalies (modifications/defects) were recorded as holes (52.7%) in 105 webs (100%) and supernumerary (0.7%) in 55 webs (52.4%), respectively. Road disturbance had a negative influence on the spider’s behavior as the webs formed in close proximity to the road had a higher frequency of anomalies, with a gradual decrease distantly. We can gain further insight into how different environmental changes, disruptions, and pollutants lead to this imperfection in the otherwise flawless perfect structure of spider webs.

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