Dispersal in the Urban Matrix: Assessing the Influence of Landscape Permeability on the Settlement Patterns of Breeding Songbirds

Abstract

The ability of organisms to disperse across urban landscapes is theorized to be constrained by habitat fragmentation. While previous research has shown the distribution of forest patches is a determinant of dispersal patterns among forest-obligate bird species, the impacts of habitat distribution on the dispersal of "urban-adapted" species, has yet to be examined. Here, we use capture-reencounter data of birds banded over a 9-year period at six banding stations in greater Washington, DC to assess dispersal in four species of songbirds and a translocation experiment to examine the influence of land cover on movement. Point count and land cover data were used to construct habitat suitability and landscape permeability surfaces, with the latter representing potential travels costs from the capture location to the surrounding landscape. To assess how dispersal processes are affected by urban land cover, we searched for previously banded birds at sampling locations within 1.5 km of each banding station and compared the distribution of sampling locations with and without observations of previously-banded birds. We found evidence that settlement of two of four focal species, the Northern Cardinal (Cardinalis cardinalis) and Gray Catbird (Dumetella carolinensis), was more likely in sites with high relative permeability. To experimentally explore the consequences of the urban matrix habitat on movement, we attached radio transmitters to male Cardinals, translocated individuals 1.5 km across high-intensity urban, suburban, and forested landscapes, and recorded the time to return to their territory. Return time was dependent on land cover with Cardinals translocated across suburban habitats returning significantly faster than those moved across the other two land use classes. Combined, our findings suggest that, even among some "urban-adapted" species, dispersal within urban environments may be influenced by landscape structure and composition.

Least‐cost path analysis for urban greenways planning: A test with moths and birds across two habitats and two cities

“…Five weighted resistant maps were produced, each corresponding to a different sized sliding window: 15, 25, 35, 55 and 75 m in diameter. This range is consistent with the perceptual range of our biological models (for moths, we used butterflies as proxy: Merckx & Van Dyck, 2007; Pe'er et al, 2004; passerines: Evans et al., 2017).…”

Residential yard management and landscape cover affect urban bird community diversity across the continental USA

“…2013, Evans et al. 2017). These two variables were derived from national maps of land cover surface for the conterminous United States in 2011 at 30 m 2 resolution as part of the National Land Cover Data (NLCD) set (Homer et al.…”

“…In addition to loss of habitat, other negative effects of impervious surfaces (e.g., roads, pavement, buildings) include road noise (Goodwin andShriver 2010, Klingbeil et al 2020), higher pollution (Roux and Marra 2007), and more artificial light (Ciach and Fr öhlich 2017). Impervious surface may also fragment habitat and limit dispersal, even with the presence of an intact mature canopy, because of anthropogenic mortality hazards (Evans et al 2017, Adalsteinsson et al 2018. The negative effects of impervious surface (and of urbanization as a whole) may not be fully mitigated by increases in tree canopies alone.…”

Differential post-fledging habitat use of Nearctic-Neotropical migratory birds within an urbanized landscape

“…Additionally, it has been recently shown that differences can likely arise when using different estimators of home range size [ 69 ]. Moreover, both simulation-based [ 87 ], and empirical studies have demonstrated support for how differences in landscape permeability within urban areas can influence bird movement [ 88 – 90 ].…”