Capacity of dispersal of a colonizing species: Drosophila subobscura

The European species Drosophila subobscura has colonized, in a very short time, large areas in South America (Chile and Argentina) and North America (The Pacific Coast, from Vancouver to Southern California), where it has been established as a very common species. Its capacity of dispersal was analyzed and results compared with the few data available from other authors. The estimates of the mean distance travelled during one activity period (159.20 meters) are considerably higher than those obtained by other authors. The Brownian motion model seems most probable because the values of DF and BM are very much alike. The effects on the estimates of some environmental factors, such as wind, are also discussed.