Riparian areas potentially provide crucial corridors through fragmented landscape for black-capped vireo ( Vireo atricap
- PDF / 4,040,430 Bytes
- 10 Pages / 595.276 x 790.866 pts Page_size
- 2 Downloads / 128 Views
RESEARCH ARTICLE
Riparian areas potentially provide crucial corridors through fragmented landscape for black-capped vireo (Vireo atricapilla) source-sink system Samantha S. Hauser1,2 · Paul L. Leberg1 Received: 17 December 2019 / Accepted: 24 September 2020 © Springer Nature B.V. 2020
Abstract Dispersal is a foundational ecological and evolutionary process that facilitates population connectivity and resiliency and yet is vastly understudied. With landscape genetics, we can elucidate how environmental features and patch characteristics influence gene flow and therefore dispersal. Our main objective was to investigate how landscape features influence gene flow in the black-capped vireo source-sink system in central Texas. We genotyped 338 black-capped vireos at 12 microsatellite loci from 6 differentiated populations to test the relationships of Euclidean distance, elevation, and land cover types (water, development, forest, scrub, open, agriculture and riparian) with gene flow. We also tested how at-site variables, brownheaded cowbird control and area of scrub habitat, affected gene flow in our models. We found that riparian and agricultural areas facilitate gene flow while development and open habitat impede gene flow. Agriculture as a potential corridor was an unexpected finding in need of further study but indicates an exciting new avenue for black-capped vireo dispersal research. In combination with findings from Dittmar et al. (2014), we inferred that riparian areas may be important corridors for black-capped vireo dispersal during post-fledgling movements, particularly in fragmented landscapes. Therefore, protecting riparian areas may help mitigate the isolating effects of habitat fragmentation and would be an important conservation effort as habitat fragmentation continues in the future. Keywords Landscape genetics · dispersal · Gene flow · movement
Introduction Dispersal describes the movement of individuals among populations and is one of the most important factors in ecology and evolution. Dispersal allows individuals to escape situations of environmental change (e.g., habitat loss), or overcrowding and resource depletion, i.e., density-dependent dispersal (Gadgil 1971; Roff 1975; Vance 1984). At a population level, dispersal is responsible for species range expansion (Paradis et al. 1998), and maintaining metapopulation (Gandon and Michalakis 1999; Paradis et al. 1998) * Samantha S. Hauser [email protected] 1
Department of Biology, University of Louisiana at Lafayette, Billeaud Hall Room 108, 410 East St. Mary Blvd, 70503 Lafayette, LA, USA
Present Address: Department of Biological Sciences, University of Wisconsin – Milwaukee, P.O. Box 413, 53211 Milwaukee, WI, USA
2
or source-sink dynamics (Amarasekare 2004; Diffendorfer 1998). However, there are physiological costs to dispersal, such as lower probabilities of survival and increased risk of predation associated with dispersal, so animals choose a path through the landscape that reduces these costs and risks (Nowakowski et al. 2
