My co-author Eyal just alerted me that our paper modeling population dynamics under urbanization is finally out in print today! Its been a long haul getting this thing out, and I plan to write more about it (in non-mathematical terms) here one of these days, once I recover from this last semester…
In the meantime, here’s the full citation:
John M. Anderies, Madhusudan Katti and Eyal Shochat. 2007. Living in the city: Resource availability, predation, and bird population dynamics in urban areas. Journal of Theoretical Biology, 247:36-49.
Unfortunately the full article is behind a institutional/paid subscription firewall, but I’ll be happy to shoot you a PDF reprint. Just let me know. If you have online access to the journal, clicking the citation links above will take you to the paper. You may read the abstract here below the fold:
Living in the city: Resource availability, predation, and bird population dynamics in urban areas
aSchool of Sustainability, Arizona State University, P.O. Box 873211, Tempe, AZ 85287-3211, USA
bDepartment of Biology, M/S SB73, California State University, Fresno, CA 93740-8027, USA
cGeorge Miksch Sutton Avian Research Center, Bartlesville, OK, 74005-2007 USA
Received 29 July 2006; revised 28 November 2006; accepted 20 January 2007. Available online 20 February 2007.
This article explores factors that shape population structure in novel environments that have received scant theoretical attention: cities. Urban bird populations exhibit higher densities and lower diversity. Some work suggests this may result from lower predation pressure and more predictable and abundant resources. These factors may lead to populations with few winners and many losers regarding access to food, body condition, and reproductive success. We explore these hypotheses with an individual-energy-based competition model with two phenotypes of differing foraging ability. We show that low frequency resource fluctuations favor strong competitors and vice versa. We show that low predation skews equilibrium populations in favor of weak competitors and vice versa. Increasing the time between resource pulses can thus shift population structure from weak to strong competitor dominance. Given recent evidence for more constant resource input and lower predation in urban areas, the model helps understand observed urban bird population structure.
Keywords: Resource dynamics; Predation; Population dynamics; Urban; Birds