The red-tailed hawk will mate for life.
More Info: One type of hawk, the red-tailed hawk of the Western Hemisphere, will mate for life if conditions allow it. All of the other raptors named hawks of the family Accipitridae are likely to be monogamous until that time that the babies are grown and ready to leave the nest.
Courtship for many hawks is a spectacular, semi-choreographed affair evolved over many millenia. Most commonly seen in North America and throughout Central America and even the Caribbean is the red-tailed version (Buteo jamaicensis). After a mating pair make graceful aerial circles at high altitude, the male red-tailed hawk will plummet toward the earth then back up to where the female is still circling on high. The two will consummate the act a little later in the same way, while falling toward the ground like skydivers with built-in parachutes.
These same hawks are the only species known to regularly mate for life. Both will incubate their seasonal eggs and take turns feeding them until they’re ready to fly off a month or two later.
Other Species that Mate for Life
About 90 percent of bird species are monogamous, according to a Stanford University research paper, though only certain species will be so for life. Some other birds that are in it for the long haul: species of the albatross, eagle, penguin, petrel, swan, goose and owl.
“Red-Tailed Hawks, Red-Tailed Hawk Pictures, Red-Tailed Hawk Facts – National Geographic.” Animals – Animal Pictures – Wild Animal Facts – Nat Geo Wild – National Geographic. N.p., n.d. Web. 26 Nov. 2012. http://animals.nationalgeographic.com/animals/birds/red-tailed-hawk/
“Hawks – Characteristics And Behavior – Prey, Female, Species, and Nests – JRank Articles .” Science Encyclopedia – JRank Articles . N.p., n.d. Web. 26 Nov. 2012. http://science.jrank.org/pages/3229/Hawks-Characteristics-behavior.html
“Monogamy.” Stanford University. N.p., n.d. Web. 26 Nov. 2012. http://www.stanford.edu/group/stanfordbirds/text/essays/Monogamy.html