These are simply vortex generators which have been a post-production modification in many models of GA aircraft (most notably Rutan canard models) for decades.

These are simply vortex generators which have been a post-production modification in many models of GA aircraft (most notably Rutan canard models) for decades. They induce turbulent flow (vortices) which, under the correct circumstances, can actually benefit range, albeit, at the cost of overall lift efficiency across the originally designed flight envelope. To use Randall Munroe's "Thing Explainer" vocabulary, they enable the aircraft to "go slower better", but at the expense of making it "go faster worse".