Use of Restoration Plantings to Enhance Bird Seed Dispersal at the Roadside: Failures and Prospects

Abstract

Plantings are commonly used in roadside reclamation for ornamental purposes and for increasing slope stability and road safety. However, the role of these plantings in restoring ecological processes, such as seed dispersal, has received little attention. We carried out a study to assess the potential role of plantings on roadside embankments to attract frugivorous birds and to enhance seed dispersal mediated by birds from the surrounding landscape. We examined: (1) bird species richness and abundance; (2) patterns of avian spatial distribution within embankments and (3) seed dispersal mediated by birds. Bird richness and abundance did not differ between embankments with and without plantings. However, birds were not distributed randomly within embankments, with levels of species richness and abundance for facultative frugivorous between 4.8–8 times higher in areas closer to plantings. An analysis of bird droppings showed that birds only dispersed seeds of the planted species since no seeds of woody plants from matrices were detected. These results suggest that plantings acted as selective bird attractors, providing food and perches for frugivorous species. Nevertheless, the scarcity of seed-dispersing birds in the surrounding agricultural landscape prevented plantings from enhancing seed dispersal and connectivity to adjacent habitat.

Ecological connectivity networks in rapidly expanding cities

“…Birds are indicators of abundance of biodiversity inhabiting an urban area and provide an indicator for ecological functions of green space such as seed dispersal [9] . Bird dispersal is considered a major driver of plant community dynamics over time and important in increasing the vegetation cover in the urban landscape [ 38 , 39 ]. Specifically, frugivorous and granivorous birds constitute the most effective mobile links for connecting habitats, acting as dispersers of seeds from fruit plants, off-plant and the ground [ 39 , 40 ].…”

“…Specifically, frugivorous and granivorous birds constitute the most effective mobile links for connecting habitats, acting as dispersers of seeds from fruit plants, off-plant and the ground [ 39 , 40 ]. These mobile organisms can provide connectivity between isolated areas in fragmented environments [38] . Consequently, several studies on urban landscapes have been carried out using bird species as indicators of habitat quality [ 17 , 41 , 42 ].…”

A Cellular Automata Model for Monitoring and Simulating Urban Land Use/Cover Changes Toward Sustainability

“…By monitoring the derivers and evaluating the impacts, decision-makers and conservation planners can find optimal solutions that describe sustainable development (Kucas 2010) Human-induced changes in land use often result in habitat fragmentation and loss. Simulation of land use change can help to environmental protection even in predicting and measuring the connectivity between adjacent habitats (Torre et al 2015).…”

Can linear transportation infrastructure verges constitute a habitat and/or a corridor for vertebrates in temperate ecosystems? A systematic review

“…From 2 to 4 years after the intervention, the authors found a positive effect on otter incidence. The other study was about clump planting fleshly-fruited woody species on highway embankments, to enhance bird seed dispersal on the roadsides, in a context of highly deforested agricultural surrounding landscape [118]. One year after the intervention, the authors did not find any statistically significant difference in species richness nor abundance between embankments with or without plantings.…”

“…The choice of the measurement period may be of particular importance for the specific question Q1 on the influence of management practices on biodiversity in verges. For instance, in a study assessing bird response to planting fleshly-fruited woody species on highway verges, measurements were performed only 1 year after the intervention, and no effect of the intervention on bird communities was found [118]. In this case, the lack of effects may be due to a delayed response of bird communities to the intervention, which was not considered in the protocol of the study.…”