Replacing Sources with Sinks: When Do Populations Go Down the Drain?

We investigate the scenario in which some amount of higher quality habitat is destroyed and is then replaced by some undetermined amount of lower quality habitat. We examined how much low-quality habitat would need to be created to maintain the equilibrium population abundance in the entire geographic area. Using a source‐sink model, we find that (1) the number of hectares of created habitat per hectare of destroyed habitat must equal the ratio of the high-quality habitat’s productivity to the low-quality habitat’s productivity, however, (2) if the created habitat is a sink, then there is a threshold fraction of destroyed high-quality habitat below which the initial population abundance cannot be maintained through the creation of habitat. We illustrate these results using data on Redwinged Blackbirds (Agelaius phoeniceus) in two different regions where high-quality habitat is being replaced by or converted into lower quality habitat.

[1]  F. Thompson,et al.  Reproductive Success of Migratory Birds in Habitat Sources and Sinks , 1995 .

[2]  F. Thompson,et al.  Modeling the effects of habitat fragmentation on source and sink demography of neotropical migrant birds , 1995 .

[3]  Miguel Delibes,et al.  Effects of an Attractive Sink Leading into Maladaptive Habitat Selection , 2001, The American Naturalist.

[4]  K. Vierling.  SOURCE AND SINK HABITATS OF RED-WINGED BLACKBIRDS IN A RURAL/SUBURBAN LANDSCAPE , 2000 .

[5]  G. Hensler.  Estimation and Comparison of Functions of Daily Nest Survival Probabilities Using the Mayfield Method , 1985 .

[6]  Gregory J. Davis,et al.  Juvenile dispersal, limited breeding sites, and the dynamics of metapopulations , 1992 .

[7]  Breeding and nonbreeding season mortality of territorial male red-winged blackbirds (Agelaius phoeniceus) , 1987 .

[8]  D. Doak.  Source‐Sink Models and the Problem of Habitat Degradation: General Models and Applications to the Yellowstone Grizzly , 1995 .

[9]  Thomas B. Ford,et al.  REPRODUCTIVE SUCCESS OF FOREST-DEPENDENT SONGBIRDS NEAR AN AGRICULTURAL CORRIDOR IN SOUTH-CENTRAL INDIANA , 2001 .

[10]  H. Pulliam,et al.  Sources, Sinks, and Population Regulation , 1988, The American Naturalist.

[11]  Andrew F. Bennett,et al.  Thresholds in landscape parameters: occurrence of the white-browed treecreeper Climacteris affinis in Victoria, Australia , 2004 .

[12]  Daniel A. Cristol,et al.  AVIAN COMMUNITIES OF CREATED AND NATURAL WETLANDS: BOTTOMLAND FORESTS IN VIRGINIA , 2003 .

[13]  W. Searcy,et al.  Sexual Size Dimorphism and Survival of Male and Female Blackbirds (Icteridae) , 1981 .

[14]  D. Fankhauser.  Annual adult survival rates of blackbirds and starlings , 1971 .

[15]  D. E. Andersen,et al.  EDGE EFFECT ON NESTING SUCCESS OF GROUND NESTING BIRDS NEAR REGENERATING CLEARCUTS IN A FOREST-DOMINATED LANDSCAPE , 2002 .

[16]  D. Fankhauser.  Survival rates in red-winged blackbirds , 1967 .

[17]  A. Poole,et al.  Red-winged Blackbird (Agelaius phoeniceus) , 2019, Birds of the World.