Sharp-Shinned Hawk

Quick Take

• Sharp-shinned hawks are regulars at backyard bird feeders, though not for the reason you'd expect. See their feeder behavior →
• The male brings food to the nest, though he always removes one part first, and the reason reveals something strange about how the family dynamic works. Explore the brooding details →
• In the wild, sharp-shinned hawks live a fraction of their potential lifespan, and this gap is far wider than what most predatory birds experience. See the lifespan gap →
• Juvenile and adult sharp-shinned hawks follow completely different migration routes, and scientists still disagree on why. Explore the migration routes →

The sharp-shinned hawk belongs to a small group of hawks called “birdhawks,” which consists of three of the smallest hawk species. These hawks are about the same size as a blue jay and inhabit dense forests throughout the Caribbean Islands, North, South, and Central America.

Their name derives from the sharp, compressed keel on the leading edge of their legs. Most information collected about the sharp-shinned hawk happens during migration because they are very secretive birds and occupy dense vegetation during the breeding season.

However, they dominate the skies of most coastal and inland watch sites during migration season and are one of the most common sightings. In addition, locals often see them visiting backyard bird feeders to find prey.

They earned a bad reputation in the birding community due to their appetite for songbirds and had very little protection from human threats until the 20th century.

These fiery little hawks have short, rounded wings with long, narrow tails. They have large eyes and elongated middle toes that help capture mobile prey.

Three Incredible Sharp-Shinned Hawk Facts

• Female sharp-shinned hawks are larger than the males, and the difference in size determines the size of their prey. Males generally catch smaller animals, which they bring home for their nestlings. However, once the chicks start to grow, they switch to the larger prey their mother brings home. Before returning the meal to the nest, male sharp-shinned hawks will generally remove and eat the head.
• Sharp-shinned hawks have elongated middle toes with sharp talons that help impale and grip fast-moving prey. They are so agile that these hawks have been known to reach into wire mesh bird traps to grab small prey within.
• The fledglings can still rely on their parents for food for several weeks. The adults will generally drop a dead meal into the nest at first; however, as the fledglings start to show some skill, the parents will begin to pass live prey to them while in the air. Finally, they will give the fledglings a warning call and expect them to approach and grab the prey out of their talons.

Where to Find the Sharp-Shinned Hawk

The sharp-shinned hawk inhabits densely forested areas all over Central America, North America, South America, and the Caribbean Islands.

They like to inhabit woodlands and forest regions, including broad-leaved and coniferous trees. Sharp-shinned hawks prefer mild temperatures and often migrate south to warmer climates for the winter. In addition, they can fly at altitudes of 960 to 9840 feet, and if necessary, can go as high as 13,000 feet.

Nests

These clever little hawks nest within small groves of thick evergreen trees with clearings nearby. They build their nests with thin twigs, bark, and greenery. Their nests typically measure 20 to 25 inches across.

For structure, they will generally place a horizontal branch against the main trunk of the evergreen. Although pairs often return to the same nesting area, they very rarely use the same nest.

Classification and Scientific Name

The sharp-shinned hawk’s scientific name is Accipiter striatus. They belong to the Order Accipitriformes, which includes several diurnal birds of prey like eagles, vultures, hawks, and kites, but excludes falcons.

Sharp-shinned hawks are one of the families within the family Accipitridae. Members include small to large birds with hooked bills and similar diets.

Their common name is a sharp-shinned hawk, and it’s derived from the sharp, compressed keel on each of their legs.

There are 10 subspecies, which include:

• A. s. chionogaster
• A. s. erythronemius
• A. s. fringilloides
• A. s. madrensis
• A. s. perobscurus
• A. s. striatus
• A. s. suttoni
• A. s. velox
• A. s. venator
• A. s. ventralis

Size and Appearance

Male sharp-shinned hawks are smaller than the females, measuring 9 to 11 inches long, weighing 3 to 4 oz, with a wingspan of 17 to 23 inches. Females are generally 30% larger than males and twice their weight. They measure 11 to 15 inches long, weigh between 5.5 and 8 ounces, and have a wingspan of 23 to 27 inches.

These measurements were taken from the northern group; however, the comparison is very similar to the remainder of the subspecies.

Adult sharp-shinned hawks have short, broad wings and a medium-length tail with grayish-black bands. However, the tip of their tails varies among individuals. They could be slightly rounded, notched, or square.

Sharp-shinned hawks have long, skinny legs, yellow in color. In addition, they have a black hooked bill with a yellowish cere.

Migration Pattern and Timing

The sharp-shinned hawk is one of 26 North American raptors that practice partial migration. Depending on their location, some populations migrate while others do not. This causes overlap between breeding and non-breeding areas. For example, the sharp-shinned hawk that inhabits the Northern Boreal forests of Canada is more migratory than southern populations.

When migrating, the sharp-shinned hawk will desert their nesting territories and breeding grounds for 5 to 7 months. The majority of North American Sharp-shinned hawks spend their winters in the warmer regions of North America; however, some populations migrate over thousands of miles to Central America and the West Indies.

Interestingly, sharp-shinned hawks avoid crossing over significant water sources. If there is a water barrier in their way, they will turn back the way they came until they find an alternative path.

Although this is a secretive species, they are the most commonly sighted Accipiter at North American watch sites during the migratory season. While they are generally solitary when migrating, it is not uncommon to see them in small groups, including other hawk species like:

• Red-tailed Hawk
• Broad-winged Hawk
• American Kestrels

Migratory Patterns

Migratory patterns can differ between adults and juveniles. For example, juveniles come out in numbers along the coastal areas, while similar numbers of adults and juveniles migrate inland.

Scientists haven’t figured out why their paths differ. However, one theory suggests that juveniles aren’t as strong and are easily blown off course compared to adults, which leads to the weaker individuals seeking an easier path on the coast.

A second theory seems more plausible and suggests that the coastal path provides the juveniles with an abundance of songbird prey.

Juveniles tend to migrate before the adults in the autumn months and generally fly farther south than their older counterparts. This is a difference that typically emerges in partial migrants.

There are also differences in sexes when migration occurs. For example, males will migrate ahead of females regardless of age or class.

In addition, females tend to conserve their energy and migrate over shorter distances compared to males. However, this is not the only reason. Because females are larger, they are more dominant, having first claim on resources and force weaker individuals to migrate further.

Behavior, Reproduction, and Molting

Sharp-shinned hawks are very secretive because of the dense vegetation they inhabit, so most of their behavior patterns were deduced during migration. Luckily, sharp-shinned hawks are one of the most common sightings during this season, and much information has been gathered over the years.

Diet

Unlike eagles, which swoop down on prey in the open air, sharp-shinned hawks stalk their prey from a tree or dense vegetation. Once the animal gets close enough, it will strike.

In addition, they are skilled hunters who can navigate through dense thickets, but this sometimes comes at a price. Speeding through dense vegetation often leads to serious injuries.

Sharp-shinned hawks prefer eating various songbirds, such as:

• Sparrows
• Finches
• Nuthatches
• Wood-warblers
• Wrens
• Tits
• Thrushes
• Icterids
• Flickers
• American Robins

Because males are smaller, they tend to go for smaller prey like the wood warblers and sparrows, while females typically target larger birds like flickers and American Robins. This is great for harmony between the sexes, as they don’t compete for the same food.

Sharp-shinned hawks are highly intelligent and will scout out bird feeders in backyards, attacking large groups to increase their odds. In addition, they will take the time to pluck the feathers off their prey before eating.

These hawks don’t only eat birds; they also consume

• Rodents
• Lizards
• Frogs
• Snakes
• Large insects

Reproduction

Collecting information about the sharp-shinned hawk during breeding season is challenging because they are hardly ever seen above the forest canopy. What is evident is that these birds of prey prefer to nest in groves of dense evergreen trees, typically with clearings nearby.

Their nests measure between 20 and 25 inches in length and are made from thin twigs, bark chips, and greenery. In addition, they will build their nests on a horizontal branch against the main trunk for more support.

While pairs generally return to the same nesting location each year, it is highly unlikely they will use the same nest; instead, they will build a new one. The female will incubate their 4 or 5 egg clutches over 30 to 32 days. After the sharp-shinned hawk eggs have hatched, the female will stay and brood the eyases for around 2 weeks while the male goes out to hunt.

Once brooding is over, the female will share hunting duties with the male. However, the eyas don’t waste any time and leave the nest between 24 and 27 days old. Juvenile males develop faster than females and typically leave the nest first.

For a month after the hawks fledge, the juveniles will stay close to each other. Their parents will still help with food, but it’s not much, forcing the fledglings to learn to hunt independently.

Luckily for them, they fledge at the same time as songbirds, making it easier for the juveniles to catch their favorite prey.

Molting

During the autumn months, juvenile sharp-shinned hawks are still in complete plumage and have yet to molt. Their first experience with molting only occurs the following April and lasts throughout the summer. Bird enthusiasts often mistake the juvenile’s barred flank feathers for the barred underside feathers of an adult hawk because they look so similar. Still, they won’t develop their new adult feathers until the summer.

Lifespan

In captivity, sharp-shinned hawks can live up to 13 years. However, in the wild, this number is significantly reduced to 3 years! Unfortunately, risks include hunting, getting hit by cars, flying into buildings, and natural predators.

Predators, Threats, and Conservation Status

Sharp-shinned hawks are listed as of Least Concern on IUCN’s Red List, although their population trend is currently decreasing.

Although there is no clear-cut data on their population size, it is estimated that there are over 1 million sharp-shinned hawks worldwide.

While that is excellent news, the sad reality is that they will eventually lose their habitat due to deforestation, as sharp-shinned hawks prefer breeding in dense forests, which are diminishing by the day.

One of their biggest threats was the misuse of DDT between 1940 and 1970. DDT is an insecticide that has caused devastating effects on animals and their surroundings. This toxic chemical was responsible for considerable declines in the sharp-shinned hawk population during this time.

Luckily, it became illegal to use DDT in the 1970s, and the sharp-shinned hawk population recovered and is flourishing.

What Eats the Sharp-Shinned Hawk?

Unfortunately, sharp-shinned hawks are not at the top of the food chain, and they need to be wary of larger birds of prey, which can make a quick meal of them. These predatory birds include:

• Northern Goshawk
• Cooper’s Hawk
• Peregrine Falcon

Population

It’s tough to determine the population size of the sharp-shinned hawk because they are such secretive birds and only partially migrate. Because most of the information about this species is collected during migration, it makes it more difficult because not all of the populations migrate. However, their population is estimated to be about 700 000 to a million birds.