Anthropogenic Nest Materials May Increase Breeding Costs for Urban Birds

Abstract

Even in socially monogamous species, sexual conflict is one reason that often promotes differences in the roles of sexes during reproduction, which may lead to one sex making a disproportionate contribution, and thus incurring disproportionate costs, at particular moments of the breeding process. In Mexico City, a number of songbird species line their nests with fibers from discarded cigarette butts, which reduce ectoparasite load but are genotoxic. As male Passer domesticus make substantial contributions to nest building whereas male Carpodacus mexicanus do not contribute to nest building, we hypothesized that the toxic effects of exposure to cigarette butts should be greater for females C. mexicanus than for conspecific males, but that there should be little or no difference in P. domesticus. As expected there was more exogenous genotoxic damage in the red-blood cells of incubating female C. mexicanus the more cigarette butts were found in their nest, and much more than in their conspecific males. Damage in males was not associated to cigarette butts; it was initially lower than in females, but it increased near fledging, together with their breeding effort. In both male and female P. domesticus, however, genotoxic damage was equally apparent and greater the more cigarette butts were in the nest. The novel use of a toxic, anthropogenic parasite repellent by urban birds may be thus asymmetrically increasing the breeding costs paid by the member of the pair most involved in nest building and incubation.

Bird Species

“…The nicotine appears to work as an effective insect repellent against ectoparasites and the more cigarette butts the less infested was the nest (Suárez-Rodríguez et al 2013). However, this repellent seems to come with physiological costs to the parent birds which show increased genotoxic damage (Suárez-Rodríguez et al 2017).…”

Great tits and the city: Distribution of genomic diversity and gene–environment associations along an urbanization gradient

“…Urbanization affects habitats, notably resulting in their loss, modification, or fragmentation (Crooks & Sanjayan, ). Urbanization also results in chemical, noise, and light pollution, altered temperatures, novel epidemics, predation risks, all in all resulting in the modification of species assemblage and demography (Aronson et al., ; Galbraith, Jones, Beggs, Parry, & Stanley, ; Shryock, Marzluff, & Moskal, ; Vincze et al., ), phenotypic traits (Alberti et al., ; Biard et al., ; Suárez‐Rodríguez, Montero‐Montoya, & Macías Garcia, ), and evolutionary dynamics (Alberti, ; Anderies, Katti, & Shochat, ; Hendry, Gotanda, & Svensson, ). Although urbanization generally results in dramatic local biodiversity declines as a lot of species avoid or are unsuccessful in urban environments, other species are able to cope and even take advantage of such environmental change via plastic or adaptive responses (Lancaster & Rees, ; Møller et al., ).…”

Use of anthropogenic material affects bird nest arthropod community structure: influence of urbanisation, and consequences for ectoparasites and fledging success

“…Anthropogenic material incorporated into nests may also be hazardous to bird survival and breeding success, particularly by causing entanglement (Votier et al 2011;Townsend and Barker 2014), but possibly also through more subtle effects on bird health. For example, House Sparrows Passer domesticus incorporating discarded cigarette butts into their nests reduce their ectoparasite load at the cost of exposure to toxins (Suárez-Rodríguez et al 2017). For the purposes of this study we define anthropogenic material as highly processed anthropogenic material (e.g.…”