Magpies are very territorial and protective of their nests. During the nesting season they will mob and attacks humans, pets and other birds near their nests. They will also bully other birds at feeders. Magpies tend to live in colonies. Large aggregations of these birds, usually in winter, can be very noisy and increase fecal droppings at roosts. The presence of magpies can increase local predation of beneficial wildlife. During nesting magpies become aggressive and the mobbing of pets and people is common, but usually harmless for people. In addition, as magpie numbers increase there is increased foraging in your gardens, fruit trees and garbage. Magpies will easily tear open plastic trash bags to get at the garbage, spreading trash around and attracting other nuisances like dogs, raccoons, skunks, etc.

Magpies have large nesting structures, sometimes 48″ high by 40″ wide, which are built of sticks in low bushes or trees fairly low to the ground, rarely being over 25′ high. These large nests can be unsightly and damage plant structures.