In the 19th century, the range of the Northern Mockingbird expanded northward towards provinces such as Nova Scotia and Ontario and states such as Massachusetts, although the sightings were sporadic. Within the first five decades of the 20th century, regions that received an influx of mockingbirds were Maine, Vermont, Ohio, Iowa, and New York. In western states such as California, the population was restricted to the Lower Sonoran regions but by the 1970s the mockingbird was residential in most counties. Islands that saw introductions of the mockingbird include Bermuda (in which it failed), Barbados, St. Helena, Socorro Island, the Cayman Islands and Tahiti.
Very interesting notes on the changes in range; a similar pattern is now occurring in Costa Rica with the Tropical Mockingbird, now present almost daily in my garden for the first time.
The singer of many songs! Very nice shots, HJ, I enjoy listening to these birds although they trip me up sometimes when I’m trying to ID a bird by song! 🙂
These birds are very territorial and will defend their territory fiercely. Even against humans if they get close to the nest. However, they like to be in urban areas. I can just imagine that certain places have many local competitors or predators. Thanks , D. 🙂
H.J. Ruiz - Avian101 
Very interesting notes on the changes in range; a similar pattern is now occurring in Costa Rica with the Tropical Mockingbird, now present almost daily in my garden for the first time.
The mockingbirds are extending their territories constantly. I got mockingbirds nesting in my backyard for almost 15 years. 🙂
The singer of many songs! Very nice shots, HJ, I enjoy listening to these birds although they trip me up sometimes when I’m trying to ID a bird by song! 🙂
I like them around in my backyard. They are fearless! Thank you, Donna. 🙂
I suppose the expanding human population had a positive impact for them, turning previously inhospitable terrain into prime habitat?
These birds are very territorial and will defend their territory fiercely. Even against humans if they get close to the nest. However, they like to be in urban areas. I can just imagine that certain places have many local competitors or predators. Thanks , D. 🙂