Urbanisation and nest building in birds: a review of threats and opportunities

Abstract

The world is urbanising rapidly, and it is predicted that by 2050, 66% of the global human population will be living in urban areas. Urbanisation is characterised by land-use changes such as increased residential housing, business development and transport infrastructure, resulting in habitat loss and fragmentation. Over the past two decades, interest has grown in how urbanisation influences fundamental aspects of avian biology such as life-history strategies, survival, breeding performance, behaviour and individual health. Here, we review current knowledge on how urbanisation influences the nesting biology of birds, which determines important fitness-associated processes such as nest predation and community assembly. We identify three major research areas: (i) nest sites of birds in urban areas, (ii) the composition of their nests, and (iii) how these aspects of their nesting biology influence their persistence (and therefore conservation efforts) in urban areas. We show that birds inhabiting urban areas nest in a wide variety of locations, some beneficial through exploitation of otherwise relatively empty avian ecological niches, but others detrimental when birds breed in ecological traps. We describe urban-associated changes in nesting materials such as plastic and cigarette butts, and discuss several functional hypotheses that propose the adaptive value and potential costs of this new nesting strategy. Urban areas provide a relatively new habitat in which to conserve birds, and we show that nestboxes and other artificial nest sites can be used successfully to conserve some, but not all, bird species. Finally, we identify those subject areas that warrant further research attention in the hope of advancing our understanding of the nesting biology of birds in urban areas.

Distance to landfill and human activities affects the debris incorporation into the white stork nests in urbanized landscape in central Spain

“…In avian taxa, the incorporation of durable anthropogenic nest materials (hereafter called ‘debris’) into nests may be considered a consequence of human activities (Wang et al 2009 ; Lee et al 2015 ). This is consistent with the fact that in an environment with greater human activity, as measured by the HFI, where the probability of debris incorporation into nests is higher (Jagiello et al 2019 ), birds incorporate debris intentionally perhaps as a result of scarcity of natural nest materials in human-impacted environments (Antczak et al 2010 ; Lee et al 2015 ; Reynolds et al 2019 ), ectoparasite defence (Suárez-Rodríguez et al 2012 ), or signal to conspecifics (Sergio et al 2011 ).…”

“…The nests were selected according to the criterion of increasing proximity to the large city of Madrid, ranging from 60 to 0.5 km away. La Torrecilla and Alcalá de Henares are human-altered areas-as measured by HFI (in both locations human activities are high) south of Madrid; the storks nest in the former is on a cattle farm, in the vicinity of Madrid's biggest landfill, whereas the latter locations is a city with approximately 200,000 inhabitants (Prieto 2002). Prado Herrero is a private cattle farm inside a protected area (Cuenca Alta del Manzanares Regional Park), whereas the Valle del Lozoya is located in an area characterized by ash trees (Fraxinus angustifolius), also settled inside a protected area (Guadarrama National Park); both of these localizations are found north-west of Madrid.…”

Urbanisation lowers great titParus majorbreeding success at multiple spatial scales

“…Cities represent potentially attractive areas to urbanpositive birds, offering several positive cues for habitat selection: they comprise concentrated sources of food such as bird feeders, urban waste and fruit-bearing exotic shrubs and trees (Mennechez and Clergeau 2001, Robb et al 2008a), as well as readily available water and convenient nesting sites in the form of nestboxes or crevices in houses (Reynolds et al 2019). However, despite these positive cues, urban areas can act as 'ecological traps' (Dwernychuk andBoag 1972, Gates andGysel 1978).…”

Nests in the cities: adaptive and non-adaptive phenotypic plasticity and convergence in an urban bird

“…As a result, birds that thrive in urban areas frequently exhibit novel nesting behaviours. Many urban populations of raptors, swifts and swallows have adapted to use buildings and other artificial sites for nests, in lieu of natural cliffs and riverbanks [36]. Tawny frogmouths (Podargus strigoides) [31], dark-eyed juncos (Junco hyemalis) [32] and Eurasian magpies (Pica pica) [37] exhibit a protracted breeding season in urban areas, possibly as a result of mild climates and/or greater food abundance compared with surrounding wildlands.…”