My son uses Vectra on his dogs, both repels and actually kills ticks if they get on the dogs.  It also seems to keep the mosquitoes and black flies off of them too; it is something applied to their skin along the line of their spine, which then soaks into the dog and works for about a month.  Toxic to humans... :( ...or wouldn't that be a nice way for us to repel those bug-gers!  His being black is going to be an extra draw for the bugs and a sure test for the Vectra.