A SPATIAL MODEL FOR THE SPREAD OF INVADING ORGANISMS SUBJECT TO COMPETITION

A spatially explicit integrodifference equation model is studied for t he spread of an invading organism against an established competitor. P rovided the invader is initially confined to a bounded region. the inv asion spreads asymptotically as a travelling wave whose speed depends on the strength of the competitive interaction and on the dispersal ch aracteristics of the invader. Even an inferior, but established, compe titor can significantly reduce the invasion speed. The invasion speed is also influenced by the exact shape of the dispersal kernel (especia lly the thickness of the tail) as well as the mean dispersal distance for each generation.