Bird use of living walls in the city of Bogotá, Colombia
Bolhuis Casas, Esmeralda Isabelle | 2016
Novel trend consisting in the installation of living walls can be evidenced in Bogotá, Colombia, a city characterized by its considerable avian diversity. Living walls have been recognized as a habitat improvement technique that may be valuable in the framework of reconciliation ecology, but very little is known about the habitat provision potential of living walls. Between 2013 and 2014, I studied bird use of living walls in the city of Bogotá. I selected a total of 13 living walls and described them in terms of height, area, and number of plant genera. At each of the sampling sites I performed a spatial analysis using GIS and measured the distance to the nearest park, forest reserve, ecological waterway corridor, and ecological road corridor; I also measured tree cover area within a 100 m radius. I recorded nesting activity in each of the living walls and carried out regular surveys on nine of these. My results indicate that only a few common urban species use living walls, mostly for foraging. A single species, the Rufous-collared Sparrow (Zonotrichia capensis), nested in living walls, discriminating in favor of the taller walls. I found a differential use of living walls, by bird species, in terms of wall zones used and activities performed in the walls. I found that plant composition is an important attribute of living walls as various plant genera provide feeding resources for hummingbirds. I also found a positive relationship between living wall area and sightings of the Great Thrush (Turdus fuscater), as well as a negative relationship between distance to ecological waterway corridors and hummingbird sightings. I conclude that living walls are of value to birds in Bogotá because they provide resources such as food, nesting sites and perching elements, and that living walls can indeed satisfy the conditions of reconciliation ecology. I also make a number of suggestions for generating value-added living walls for urban avifauna.