Aggressive behavior during mating season

Resident Canada geese are more aggressive in the spring during their nesting season, which generally takes place from late February to mid-May. Both males and females will defend their nesting sites, but males are significantly more territorial against other males, animals, or humans that they see as a threat. Once incubation begins, females may hiss or attempt to bite those who come too close, but rarely leave the nest until eggs are hatched. Males take on the protective role to defend their mates, nests, and territory. After hatching, both males and females will aggressively guard their young for about 10 to 12 weeks, but males tend to be more confrontational than females. This defensive behavior will continue until the young are mature enough to fly. 

Spacing between couples:

During spring, pairs of geese separate from flocks and become protective of their territories. Spacing between couples can vary based on flock size and habitat availability. Females typically prefer nests to be anywhere within 150 feet from water where shrubs and patches of vegetation can be used as cover. After persistent fights for territory have diminished, females may still be forced to nest within sight of one another. In areas with less habitat, females may nest less than 10 feet apart, but prefer to be spaced farther apart to avoid predation. 

Male aggression:

Males will also fight violently with other males over space, resources, or dominance. Fights among males are the most prevalent during breeding season, but can take place throughout the year depending on their environment. Since geese maintain a social hierarchy, fights may occur more frequently in larger flocks where competition is increased. Sometimes, aggression is simply a brief method of conflict resolution to maintain social order. Geese use their wings, bills, and bodies during fights, which can lead to severe injuries such as wounds or broken bones. On occasion, geese may even gang up on a single individual. Males become more defensive when food and other resources are scarce, which can be a significant problem in urban areas. Frequent interactions with humans where geese are fed or provoked can also increase aggression because geese become less fearful. 

Human response:

It is important for humans to identify aggressive body language in males in order to prevent conflicts. Common territorial behaviors include loud honking, head pumping, hissing, open bill, wing flapping, and honking. When these behaviors are present, humans should back away slowly, creating a safe amount of space from the Canada goose. Slow movement is essential, as most Canada geese-related injuries occur due to falling when attempting to run away. Wildlife professionals such as Goose Masters are trained to safely move Canada geese to more secure areas, an act that benefits both humans and geese. Remote areas with more space allow Canada geese to remain self sufficient with enough food and resources, reducing conflicts with humans and other geese.