Sparviero striato

Informazioni

The Sharp-shinned Hawk, known in Italian as Sparviere americano or Sparviero striato, is a small, agile raptor found across North and Central America. It is the smallest accipiter in North America, characterized by its short, rounded wings and long tail, adaptations for maneuvering through dense forest cover while pursuing prey. These birds are formidable predators of small birds, relying on surprise attacks and swift flight.

Dimensioni e longevità

Lunghezza

23-34 cm

Apertura alare

51-64 cm

Peso

82-218 g (males), 149-319 g (females)

Longevità

Up to 10-12 years in the wild, though average is often shorter (2-3 years)

Dieta

Carnivore (primarily small birds, occasionally small mammals, reptiles, or large insects)

Caratteristiche fisiche

Piumaggio

Adults have slate-blue to bluish-gray upperparts, with rufous barring on the underparts. The tail is dark with 3-4 broad black bands and a narrow white tip. Juveniles are brown above with streaky brown underparts, often with a buffy wash.

Forma del becco

Short, sharply hooked, dark gray to black with a yellow cere.

Colore degli occhi

Adults have dark red to reddish-orange eyes; juveniles have yellow eyes that gradually darken with age.

Colore delle zampe

Yellow

Caratteristiche distintive

Small size, short rounded wings, long square-tipped tail (often notched when worn), and rapid wing beats interspersed with glides. The head appears small relative to the body.

Aspetto giovanile

Juveniles have brown upperparts, often with rufous feather edges, and heavily streaked brown underparts on a white or buffy background. Their eyes are yellow. The tail banding is less distinct than in adults.

Cambiamenti stagionali

No significant seasonal plumage changes; plumage is consistent year-round once adult plumage is attained.

Dimorfismo sessuale

Females are significantly larger than males (up to 50% heavier and 25% longer), which is a pronounced dimorphism among raptors. Plumage is similar, though females may appear slightly duller in coloration.

Come identificare

1. 1

   Size and Shape

   Look for a very small hawk with short, rounded wings and a long, square-tipped tail. The head often appears small and barely extends beyond the wings in flight.

2. 2

   Flight Pattern

   Observe its characteristic 'flap-flap-glide' flight, often low to the ground or through dense vegetation. Wing beats are rapid and shallow.

3. 3

   Plumage (Adult)

   Adults have a dark slate-blue back and rufous barring on the white underparts. The tail has dark bands and a narrow white tip. Eyes are dark red.

4. 4

   Plumage (Juvenile)

   Juveniles are brown above with heavy brown streaking on the underparts, often with a buffy wash. Eyes are yellow.

5. 5

   Tail Shape

   The tail is typically square-tipped, though it can appear slightly notched when worn. This contrasts with the more rounded tail of a Cooper's Hawk.

Habitat e areale

Biomi

Coniferous, deciduous, and mixed forests; woodlands, suburban areas, parks, and riparian zones.

Areale geografico

Breeds across North America from Alaska and Canada south through the United States and into Mexico. Winters from southern Canada and the United States south through Central America to Panama, and in the Caribbean.

Fascia altitudinale

Sea level up to 3,000 meters (10,000 feet) in mountainous regions.

Ambienti preferiti

Dense woodlands and forests, particularly those with a mix of mature trees for nesting and open understory for hunting. They adapt well to suburban environments with sufficient tree cover and bird feeders, which attract their prey.

Comportamento

Periodo di attività

Diurnal, active during daylight hours.

Abitudini alimentari

A highly agile and stealthy hunter, primarily preying on small birds (e.g., sparrows, finches, warblers, thrushes). It hunts by perching inconspicuously and launching surprise attacks, or by flying low and fast through vegetation. It plucks feathers from prey before consumption.

Comportamento sociale

Generally solitary outside of the breeding season. During breeding, pairs form and are monogamous for the season. They are highly territorial around their nest site.

Tipo di volo

Characterized by a distinctive 'flap-flap-glide' flight pattern. Flight is fast and direct, with rapid, shallow wing beats. Highly maneuverable, especially when hunting in dense cover. Soars on thermals during migration.

Migrazione

Most populations are migratory, moving south for the winter. Northern populations undertake long-distance migrations, while southern populations may be resident or undertake shorter-distance movements. Migrates along mountain ridges and coastlines, often in large numbers during peak migration.

Territorialità

Highly territorial during the breeding season, defending a nesting territory from other raptors and potential predators. Males may defend a hunting territory during winter.

Riproduzione

Stagione riproduttiva

April to July, with peak nesting in May-June.

Abitudini di nidificazione

Nests are typically built in dense coniferous or mixed forests, often near the trunk of a tall tree (pine, spruce, fir, or oak), usually 6-18 meters (20-60 feet) above the ground. The nest is a platform of sticks, lined with bark strips, conifer needles, and sometimes green leaves.

Dimensione della covata

4-5 eggs

Descrizione dell'uovo

2-8 (typically 4-5) eggs, dull white or pale bluish-white, often lightly marked with pale brown or reddish-brown spots and blotches, especially at the larger end. Eggs measure approximately 37 x 30 mm.

Periodo di incubazione

30-35 days, primarily by the female.

Periodo di involo

21-27 days after hatching. Young remain dependent on parents for several weeks after fledging.

Cure parentali

Female incubates eggs and broods young. Male provides food for the female and young during incubation and early nestling stages. Both parents feed the young after they fledge.

Dove trovarlo

Consigli sul campo

1. Watch Bird Feeders. Sharp-shinned Hawks frequently visit bird feeders, not to eat the seeds, but to prey on the small birds attracted to them. Keep an eye out for sudden commotion among feeder birds.
2. Scan Forest Edges. Look along the edges of forests and clearings, where they often perch inconspicuously before launching an attack.
3. Observe Flight. Learn to recognize their distinctive 'flap-flap-glide' flight and their agile maneuvering through trees. They often fly low and fast.
4. Visit Hawk Watches. During fall migration (September-October), visit hawk watch sites where thousands of raptors, including Sharp-shinned Hawks, can be observed migrating south.

Specie simili

Fatti rapidi

Smallest Accipiter:

The smallest accipiter in North America.

Diet Specialization:

Highly specialized in hunting small birds.

Sexual Size Dimorphism:

Females are significantly larger than males.

Migration:

Most populations are migratory, undertaking long-distance journeys.

Flight Style:

Known for its agile, 'flap-flap-glide' flight through dense cover.

Curiosità

• The name 'Sharp-shinned' refers to the bird's slender, unfeathered legs, which appear sharp-edged.
• Despite their small size, Sharp-shinned Hawks are fierce predators and can take down prey larger than themselves, though they primarily target small birds.
• During migration, Sharp-shinned Hawks can be seen flying very low to the ground, sometimes even below tree level, as they follow contours and avoid strong winds.
• They are sometimes called 'little blue darters' due to their adult plumage and swift flight.

Classificazione scientifica

Regno

Animalia

Phylum

Chordata

Classe

Aves

Ordine

Accipitriformes

Famiglia

Accipitridae

Genere

Accipiter

Specie

Accipiter striatus

Esplora Sparviero striato