Surviving in the city: higher apparent survival for urban birds but worse condition on noisy territories

Abstract

Anthropogenic landscapes and soundscapes impose strong selective pressures on a number of species, which can manifest in changes in vocalizations, foraging strategies, predator vigilance, and reproductive success. However, few studies have examined survival rates, a major component of fitness, across urban landscapes and soundscapes. White‐crowned sparrows (Zonotrichia leucophrys) persist in both urban and rural landscapes and change their behavior in response to the soundscape. We color‐banded adult white‐crowned sparrows and collected noise levels on their territories in the urban San Francisco Bay Area and adjacent rural Point Reyes National Seashore in California. We collected mark‐encounter data on territorial males from 2014 to 2017. Using the Program MARK, we tested the effects of habitat (urban/rural) and territory noise level on annual survival rates and body condition. We predicted that survival and body condition would be lower in urban habitats and decrease with increasing background noise level on territories. We found that survival estimates vary according to year, and males in urban landscapes have higher survival. Noise levels best predict body condition, such that soundscape negatively correlates with male body condition. Taken together, the urban landscape and soundscape shape the survival and health of birds in and near cities.

Night lighting and anthropogenic noise alter the activity and body condition of pinyon mice (Peromyscus truei)

“…Increases in low frequency noise can have physiological effects on rodents by triggering stress responses (Du et al 2010) and altering organ tissue (Branco et al 2004), even if the frequency of the noise is below the range at which the rodents can likely hear (see below). A similar pattern of reduced body condition or changes in stress hormones in noisy areas has been found in multiple bird species as well, providing further evidence that elevated levels of ambient noise can induce negative, physiological effects (Kleist et al 2018, Phillips et al 2018. If these or similar direct, physiological effects occur in natural systems from noise levels and frequencies that pinyon mice can or cannot detect, it could result in an equal use ecological trap where individuals do not avoid habitat that is ultimately deleterious (Hale and Swearer 2016).…”

Anthropogenic noise in US national parks – sources and spatial extent

“…These levels of noise have been shown to affect the body condition (Phillips et al . ), behavior (Klett‐Mingo et al . ), and fitness (Schroeder et al .…”

“…Although NPS lands are among the quietest of US protected areas (Buxton et al 2017a), we found high overall median noise exceedance (>10 dB) in one-third of US national park units (2% of all park area). These levels of noise have been shown to affect the body condition (Phillips et al 2018), behavior (Klett-Mingo et al 2016, and fitness (Schroeder et al 2012) of many wildlife species. Ultimately, this level of noise exceedance can affect ecosystem services, altering processes like seed dispersal and pollination (Francis et al 2012).…”

A global synthesis of the impacts of urbanization on bird dawn choruses

“…Predation pressure has been shown to increase with urbanization (Fischer et al 2012); yet, potential influences of predation on dawn chorus timing remain untested. Additionally, although supplementary feeding is widespread in cities and can alter avian body condition (Amrhein 2014, Phillips et al 2018, Baverstock et al 2019, the effects of feeders on dawn chorus timing remain controversial, so that a larger sample of studies of its impacts would be valuable.…”