Ecologists at the University of Windsor in Ontario, have been using network theory to work out how the Russian spiny water flea (Bythotrephes longimanus) will travel through Canada's lakes. The flea is a zooplankton species that entered the Great Lakes in the 1980s, and it is eating other zooplankton needed by young fish for food. The researchers, Jim Muirhead and Professor Hugh MacIsaac claim that the spread of water fleas between lakes by boats is similar to the spread of viruses by email.
The findings will allow the limited resources available to control invasive species to be targeted at points on the network where they will have most impact. Muirhead and MacIsaac conclude, “Outbound vector traffic from hubs with large flows to non-invaded destinations should be targeted for management efforts to restrict the transportation of propagules across the network and to reduce the rate at which non-indigenous species disperse to novel sites.” In other words, use a gateway scanner and threat-reduction techniques.
Perhaps similar techniques could be used to control red fire ants in Hong Kong?