Effects of an attractive sink leading into maladaptive habitat selection

Habitat sinks can attract dispersing animals if high mortality or breeding failure are difficult to detect (e.g., when due to human hunting or polluti on). Using a simple deterministic model, we explore the dynamics of such so urce-sink systems considering three scenarios: an avoided sink, no habitat preference, and an attractive sink. In the second two scenarios, there is a threshold proportion of sink habitat above which the whole population decr eases to extinction, but this extinction threshold varies with habitat pref erence and the relative qualities of the two habitat types. Hence, it would be necessary to know the habitat preferences of any species in a source-si nk system to interpret data on population increases and declines. In the at tractive sink scenario, small changes in the proportion of sink habitat may have disproportionate effects on the population persistence. Also, small c hanges in growth rates at the source and the sink severely affect the thres hold and the time of extinction. For some combinations of demographic param eters and proportion of habitat sink, the decline affects the source first; thus, during some time, it will be hidden to population monitoring at the sink, where numbers can even increase. The extinction threshold is also ver y sensitive to the initial population sizes relative to carrying capacity. Attractive sinks represent a novel aspect of source-sink dynamics with impo rtant conservation and management implications.