Geese just seem to go insane this time of year as they defend nests, goslings and the perimeter of their turf.
It's so unlike nesting ducks, in which only the hen assumes parental responsibilities and—if disturbed—is content to fly away and wait out the threat. Geese, on the other hand, watch the nest in pairs. The goose sits on the nest while the gander keeps a watchful eye for danger. If a threat is perceived, watch out, they're coming for you whether you're an unlucky pedestrian or a Colorado moose.
My advice: Either give nesting geese a wide berth or become very good at running with your hands on your buttocks.