canada goose

-native to north america, introduced to europe
-bill length ranging from 32mm to 40 mm
-shares environment with mallards
-feeds on grasses
-reproduces sexually
-sticks with one mate for life (finds a different mate if the one they have has died)
-lays 2-8 eggs

There is a symbiotic relationship between the Canada geese and the grasses they consume. The relationship benefits the geese and doesn't harm the vegetation.

while some migrate to warmer environments some may overwinter on open water that has not froze yet