Wind-borne short-range egg dispersal in anostracans (Crustacea : Branchiopoda)

Evidence is provided for the first time that at least part of the egg bank of the southern African fairy shrimp Branchipodopsis wolfi is dispersed ove r short distances by wind. A total of 423 sticky surfaces were mounted arou nd and between individual basins at three rock pool sites, to trap any disp ersing eggs during a 3 day period. Eight viable eggs were found in differen t egg traps (1.9% of the total), seven of which were located at one site wi th shallow basins. Given the proximity of vast egg basks to the egg traps, the low observed dispersal rate cautions against overestimating the importa nce of wind dispersal for population genetic processes. By generating egg b anks to hedge against drought catastrophes, and producing egg types with di fferent potential dispersibility, B. wolfi is a strong bet-hedger which has established a means of escaping temporal and spatial stress. These life hi story functions enable populations to persist in small desert rock-pools, w hich are the most extreme of temporary habitats. (C) 1999 The Linnean Socie ty of London.