Red-Shouldered Hawk

(Buteo lineatus)

The Red-shouldered Hawk species is divided into five subspecies. Four are found in the eastern US and come in contact with each other while the single western subspecies remains isolated from the others by about 1000 miles. Opposed to the more densely forested habitat of the eastern subspecies, hawks of the western US typically reside in riparian areas, oak woodlands, and suburban areas with large trees. Previously they were only found in California and southern Oregon but in recent years their range has expanded north into Washington. In the mid-20th century pesticides such as DDT had an effect on populations of the past. Today ingesting prey poisoned by rodenticides is among the hazards they face. Currently the biggest threat to Red-shouldered Hawks is habitat loss.

Red-shouldered Hawks can be distinguished from other similar species by their long banded tails that allow them make sharp turns and the crescent-shaped translucent markings across their outer wings that can be seen when the feathers are backlit. They are smaller in size than Red-tailed Hawks. Capable of killing prey equal to their own size or smaller they capture it by dropping directly onto it from above. Sometimes birds will cache food near their nest site for a later meal.

Sound Clip of Red Shouldered Hawk (Recorded 3/2016, Rocklin, CA)

Description Diet Migration Nesting

Length: Males = 15 to 23 inches. Females = 19 to 24 inches.

Weight: Male ~ 1.21 lb. Female ~ 1.5 lb.

Wingspan: 3'2" to 3'6"

Lifespan: The oldest-known Red-shouldered hawk was a female, and at least 25 years old.

Diet consists of small mammals, lizards, snakes, and amphibians. Less commonly crayfish and birds.

Red Shouldered Hawks on the West Coast are mostly non-migratory and tend to be residents year round. (Northeast and northern midwest hawks migrate to more southerly states. Hawks in central and southern states don’t typically migrate, although some do spend winters in Mexico.)

Breeding age is 1-2 years old.

Pairs often reuse nests built in the past. Both the male and female build the 2 ft diameter nest, made up of a platform of sticks and lined with bark, moss, lichens, or conifer sprigs. Nest Location is ~35-65 feet up in the fork of a deciduous or conifer tree.

Clutch size = 2 to 5 eggs, colored dull white or faint bluish with brown blotches. Hawks have 1 brood per year. Pairs that nest earlier in the season tend to lay a greater number of eggs.

Incubation = 32 to 40 days. Hatching is asynchronous--the first chick hatches up to a week before the last.

Fledging = 42 to 49 days. Offspring remain dependent on the parents for meals until they are 17 to 19 weeks old. (They may continue to roost near the nest site until the following year.)

Red-shouldered Hawk pairs will return to the same nesting territory year after year (one individual occupied a territory in southern California for 16 consecutive years). They can be aggressive towards intruders in their territory, sometimes locking talons with intruding hawks. In our local Rocklin CA area a similar behavior was observed between a pair of soaring Red-shouldered Hawks that encountered a lone Red-tailed Hawk flying through the claimed airspace. A few passes with feet forward and talons beared took place between the hawks until the Red-Tailed Hawk decided to leave the area. Some of the event can be seen in the photos below (unfortunately the quality of the photos are lacking leaving the photographer dreaming of a better telephoto lens...). The Red-shouldered Hawk is the smaller bird and can be distinguished by the black and white bands of its tail feathers.

Juvenile Red Shouldered Hawk (above)

Juvenile Red Shouldered Hawks appear similar to several other species and can be tricky to identify (please note that best efforts were made to id hawks within the posted photos however it is possible that mistakes were made). Juveniles are light underneath with dark streaking, marked heavily on the upper chest in contrast to the adult coloration of rufous (orange-red) barring.

It was noted that the individual in these photos seemed to have an injured right outer toe. Observing the bird briefly while taking photos it seemed that the injury did not impair its ability to grip the branch, preen, or take flight.

To drive away predators from a territory, smaller birds like the mockingbird in the photo will dive at hawks in attempts to get them to leave the area. This behavior is known as mobbing and can involve coordinated efforts by several small birds. The Red-shouldered Hawk juvenile in this instance endured a few dives from the mockingbird before taking flight.

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References

1. "Red-shouldered Hawk, Life History". All about birds, The Cornell Lab of Ornithology. Cornell Lab of Ornithology. Retrieved October, 2016.
2. "Red-shouldered Hawk". Audubon Guide to North American Birds. Retrieved October, 2016.
3. "Red-shouldered Hawk". Wikipedia, The Free Encyclopedia. Retrieved October, 2016.
4. "Red-shouldered Hawk". Raptor ID fact sheets, Hawkwatch International. Retrieved October, 2016.

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