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10 Fascinating Facts About the Broad-winged Hawk

The Broad-winged Hawk is a fascinating bird species commonly found in North America. These hawks have a unique appearance and behavior, which makes them a favorite among bird enthusiasts.

In this article, we will explore the identification, plumage, and molts of Broad-winged Hawks and compare them with similar species.

Identification

Field

Identification:

– Broad wings that are long and rounded

– A broad, banded tail

– A dark head with a pale stripe above the eye

– A dark back and wings with brown and white speckling

– Underparts are whitish to buffy, with brown streaks

– Red eyes

Similar Species:

– Cooper’s Hawk: smaller with a more narrow wing and a longer tail

– Red-shouldered Hawk: larger with a reddish barring on the wings

– Sharp-shinned Hawk: smaller with a more rounded tail and a longer wing

Plumages

Broad-winged Hawks have two main plumages: juvenile and adult. Juvenile birds have brown feathers on top, and their underparts are lighter, with brown streaking.

Their eyes are yellow, and their tails have brown and white bands. Adult birds, on the other hand, have a darker back and wings, with contrasting rufous barring on the tail.

Their underparts are more buff-colored, with bars and streaks of reddish-brown.

Molts

Broad-winged Hawks have two molts each year: pre-basic and pre-alternate. The pre-basic molt occurs after breeding season, and the birds replace all their feathers, including their flight feathers.

The pre-alternate molt occurs in the spring, and the birds replace the feathers they used in courtship and territorial displays. In conclusion, the Broad-winged Hawk is a unique bird species that can be identified by its broad wings, banded tail, and dark head with pale stripes above the eyes.

The juveniles and adults have different plumages, and the birds have two molts each year. By understanding their appearance and behavior, we can better appreciate these majestic birds of prey.

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Systematics History

The Broad-winged Hawk (Buteo platypterus) has undergone some changes in its systematics history. It was initially described as Falco platypterus in 1808 by Johann Friedrich Gmelin.

Later, it was transferred to the genus Buteo by Thomas Nuttall in 1840. Since then, there have been no major changes in the placement of the species within the Buteo genus.

However, there have been debates about the classification of subspecies and the relationship of the Broad-winged Hawk to other species in the Buteo genus.

Geographic Variation

Broad-winged Hawks have distinct geographic variations in plumage coloration. It is important to note that the distribution of these variations is not based on latitude, as with some other bird species.

Instead, it is related to the distance from the coast. Hawks found closer to the coasts have darker plumage, while those in the interior have lighter plumage.

This variation may be a result of adaptation to different environments, particularly the amount of sunlight and humidity.

Subspecies

There are two recognized subspecies of the Broad-winged Hawk:

– Buteo platypterus platypterus: found in eastern North America

– Buteo platypterus cubanensis: found in the Caribbean islands

Subspecies cubanensis is smaller than platypterus and has browner upperparts. However, there has been debate over whether Buteo platypterus may actually be a cluster of several subspecies or even several separate species.

Related Species

Broad-winged Hawks are closely related to other hawks in the Buteo genus. Genetic studies have shown that the most closely related species is the Swainson’s Hawk (Buteo swainsoni).

Other closely related species include the Red-tailed Hawk (Buteo jamaicensis), Red-shouldered Hawk (Buteo lineatus), and Cooper’s Hawk (Accipiter cooperii).

Historical Changes to Distribution

Broad-winged Hawks have experienced changes in their distribution over time. In the 19th and early 20th centuries, deforestation for agriculture and logging resulted in significant habitat loss for these hawks.

This led to a decline in their populations, particularly in the eastern United States. However, since the mid-20th century, due to reforestation and protection of forests, their populations have rebounded in many areas.

In addition to habitat loss, the use of pesticides such as DDT in the mid-20th century had a significant impact on Broad-winged Hawks and other bird species. Pesticides led to the thinning of eggshells, which made them more likely to break during incubation.

This resulted in lower hatching rates and decreased populations. Conservation efforts, including the banning of DDT and the protection of migratory routes, have helped to stabilize Broad-winged Hawk populations in recent years.

However, continued habitat loss due to development and climate change may impact their future.

Conclusion

Overall, the Broad-winged Hawk is a fascinating species with distinct geographic variation in plumage, two recognized subspecies, and close relatives within the Buteo genus. While their populations have experienced fluctuations due to habitat loss and pesticide use, conservation efforts have helped to support their recovery.

Continued efforts to protect their habitats and migratory routes will be necessary to ensure the survival and stability of this important species. .

Habitat

Broad-winged Hawks inhabit deciduous and mixed forests, as well as forest edges, open woodlands, and riparian areas. Preferred habitats include mature forests with a closed canopy and a diverse understory that provides good cover and food sources for the birds.

In the winter, these hawks can be found in Central and South America, from Mexico to Brazil, occupying similar habitat types, including humid forests, savannas, and plantations.

Movements and Migration

Broad-winged Hawks are migratory birds that breed in the eastern parts of North America and spend their winters in Central and South America. They undertake one of the most spectacular raptor migrations in the world.

During the fall, thousands of Broad-winged Hawks can be seen in large flocks of up to several thousand birds, known as “kettles,” as they soar together on thermals or updrafts. These congregations provide a unique opportunity for birdwatchers to observe these majestic birds in large numbers.

In the spring, the hawks begin their journey back north, with breeding adults returning to their established nesting territories first. Once there, they engage in courtship behaviors, which can include aerial displays, vocalizations, and aggressive chases with other hawks.

Within a breeding territory, males will create nests in trees or tall shrubs, where females will lay their eggs. The hawk pairs will take turns incubating the eggs, until they hatch and the chicks are born.

Juvenile Broad-winged Hawks remain on their wintering grounds longer than their parents, and they migrate north later in the spring. Their journey north is usually completed alone or in small groups, rather than in large congregations like the adults.

Once they reach their breeding grounds, they disperse widely across a larger area. Broad-winged Hawks are known to follow certain migratory routes, including the Appalachian Mountains, the Gulf Coast, and the Atlantic Coast.

They take advantage of the thermals that rise off the mountains and seas, which enable them to travel great distances without flapping their wings. In some areas, these thermals can reach heights of over 10,000 feet, allowing the hawks to fly up to 100 miles in a single day.

Conclusion

Broad-winged Hawks are migratory birds that inhabit forests and woodland edges. During the fall, these hawks undertake one of the most spectacular raptor migrations in the world, gathering in large flocks to travel south for the winter.

They follow certain migratory routes, taking advantage of thermals to travel long distances without flapping their wings. In the spring, they return to their breeding grounds, where they engage in courtship behaviors, build nests, and raise their young.

Understanding their movements and migration patterns is crucial for their conservation, as they rely on healthy habitats and protected migratory routes to survive and thrive. .

Diet and Foraging

Broad-winged Hawks are opportunistic hunters and primarily rely on small mammals and reptiles for food. They forage by soaring over their preferred habitats, scanning the ground for prey.

They also perch on trees or other elevated platforms, from which they can scan the surrounding area for potential prey items. Feeding:

Broad-winged Hawks typically hunt by flying low over the ground and using their keen eyesight to spot prey.

Once they locate a prey item, the hawks dive down and capture it with their talons. They may also hunt by pursuing their prey through the trees, using their agility and speed to catch them as they try to flee.

Diet:

The diet of the Broad-winged Hawk is diverse and varies depending on the availability of prey. Their primary food sources are small mammals, such as rodents and shrews, and reptiles, including snakes and lizards.

They may also consume insects, amphibians, other birds, and carrion. Metabolism and Temperature Regulation:

To maintain their high energy demands for hunting and flight, Broad-winged Hawks have a high metabolism.

They produce a significant amount of heat during digestion, which helps to regulate their internal body temperature. They also have a unique network of blood vessels in their legs and feet, known as the countercurrent heat exchange system, which helps to keep their feet and talons from freezing in low temperatures.

Sounds and Vocal

Behavior

Broad-winged Hawks have a variety of vocalizations, including calls and songs used for communication, territorial defense, and courtship. Their vocalizations are generally high-pitched and often repeated in a series.

Vocalization:

The most common call of the Broad-winged Hawk is a high-pitched, drawn-out whistle, often described as “peee-uuuur.” Both males and females make this call, which can be used as a contact call between mates or family members. During the breeding season, males may also perform a display flight, accompanied by a series of shrill whistles or screams.

They may also produce a harsh screeching call, which is used during territorial disputes or to warn off potential predators. In addition to their vocalizations, Broad-winged Hawks also engage in non-vocal communication.

During courtship, males and females will engage in aerial displays and visual cues, such as head-bobbing or wing-flapping. Aggressive or territorial behavior may be indicated by erecting their body feathers, spreading their wings, and holding their tail feathers upright.

Conclusion

Broad-winged Hawks are skilled hunters that rely on a diet of small mammals, reptiles, and other prey to survive. They have high energy demands and unique physical adaptations to help regulate their internal body temperature and stay agile in flight.

They use a variety of vocalizations and visual cues to communicate with their mates, family members, and other members of their species. Understanding their diet and foraging strategies, as well as their vocal behavior, can provide insights into their ecology and help to support their conservation.

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Behavior

Broad-winged Hawks exhibit a variety of behaviors related to locomotion, self-maintenance, agonistic interactions, and sexual behavior. Understanding these behaviors can provide insights into their ecology and evolution.

Locomotion:

Broad-winged Hawks are skilled fliers, capable of soaring and maneuvering through forested and open habitats. They use thermal updrafts to gain altitude without expending too much energy.

When hunting, they fly low over the ground or through the trees, using their agile flight to capture prey. Self Maintenance:

Broad-winged Hawks engage in self-maintenance behaviors, such as preening, to keep their feathers clean and in good condition.

They will use their beak to remove dirt and debris from their feathers and may shake their bodies to dislodge any excess material. Preening helps to maintain their insulation, protect their feathers from wear and tear, and prevent the accumulation of parasites.

Agonistic

Behavior:

Broad-winged Hawks exhibit agonistic behaviors, including territorial defense, intraspecific aggression, and defense against predators. They may use vocalizations, such as screeches or screams, and visual cues, such as erecting their feathers, spreading their wings, and engaging in physical altercations, to defend their territory or establish dominance.

Sexual

Behavior:

Broad-winged Hawks have specific behaviors related to courtship and mating. During courtship, males will perform aerial displays, chase after females, and provide food offerings to potential mates.

Once mating occurs, the pair will work together to build a nest, incubate the eggs, and raise their offspring.

Breeding

Broad-winged Hawks typically mate for life and remain monogamous. Courtship and breeding typically occur in the spring, with pairs engaging in displays to establish territories and attract mates.

Once a mate is chosen, the pair will work together to build a nest in a tall tree or other elevated location. The nest consists of a platform of sticks and twigs, lined with softer materials such as grass, leaves, and other plant material.

After the nest is built, the female will lay 1-3 eggs, depending on the availability of prey items. Both parents take turns incubating the eggs for around 30 days.

Once the chicks hatch, they are altricial, meaning they are immobile and rely on their parents for food and protection. The young are fed a diet of small mammals and reptiles brought back to the nest by the parents.

They grow rapidly and fledge the nest after around 5-6 weeks.

Demography and Populations

Broad-winged Hawks are native to North and South America and have a range that extends from southern Canada to northern Brazil. The International Union for Conservation of Nature (IUCN) lists the Broad-winged Hawk as a species of “least concern” due to its relatively stable populations and extensive range.

While the populations of Broad-winged Hawks have begun to recover from habitat loss and pesticide use, there are still several threats facing them. These threats include habitat loss due to deforestation and development, climate change, and hunting or trapping.

Continued conservation efforts are essential to support their recovery and ensure their survival for future generations. Population demographics are difficult to estimate for birds, as they are highly mobile and often difficult to track.

However, citizen science efforts, such as the Audubon Christmas Bird Count, have provided valuable data on the population density and distribution of these hawks. Additionally, banding and tracking studies have helped to shed light on their migratory behavior, which is critical for monitoring and conservation efforts.

In summary, the Broad-winged Hawk is a unique bird species with fascinating characteristics and behaviors. Their systematics history, geographic variations, habitat, migration patterns, and behavior all contribute to a better understanding of their ecology and evolution.

Although they faced significant population declines due to habitat loss and pesticide use, conservation efforts and legal protections have helped them to recover. Continued efforts to preserve their habitats and migratory routes will be essential to support their populations and maintain the biodiversity of our forests.

Ultimately, understanding the Broad-winged Hawk and its role in the ecosystem is crucial for ensuring their survival and the survival of the many other species that rely on healthy forests for their survival.

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