Chestnut collared Longspur

The Chestnut-collared Longspur (Calcarius ornatus) is a small, ground-dwelling bird that inhabits the vast prairie landscapes of North America. Known for its striking breeding plumage and its affinity for open grasslands, this species plays a crucial role in the ecosystems it inhabits.

The Chestnut-collared Longspur is a small passerine bird belonging to the family Calcariidae. It is characterized by its distinctive breeding plumage, especially in males, and its preference for ground feeding in open grasslands.

Physical Characteristics

• Size: The Chestnut-collared Longspur measures about 12 to 15 centimeters (4.7 to 5.9 inches) in length.
• Weight: It typically weighs between 16 to 22 grams (0.56 to 0.78 ounces).
• Wingspan: The wingspan ranges from 25 to 28 centimeters (9.8 to 11 inches).
• Plumage:
  • Males (Breeding Plumage): Males are easily recognizable during the breeding season by their striking black underparts, a chestnut-colored nape, a bright yellow throat, and a black crown. They also have a white tail with a dark tip.
  • Females and Non-breeding Males: Both females and non-breeding males have light brown underparts, a dark crown, brown wings, and may show some chestnut on the nape, though much less pronounced than in breeding males.
  • Juveniles: Juveniles resemble non-breeding adults but are generally more streaked and lack the vibrant colors seen in adults.

Size Comparison with Other Longspurs

Taxonomy

The Chestnut-collared Longspur belongs to the genus Calcarius within the family Calcariidae. This family includes a variety of longspur species known for their adaptations to grassland environments. The species name ornatus is derived from Latin, meaning “ornate” or “adorned,” a reference to the male’s striking breeding plumage.

Scientific Classification

• Kingdom: Animalia
• Phylum: Chordata
• Class: Aves
• Order: Passeriformes
• Family: Calcariidae
• Genus: Calcarius
• Species: Calcarius ornatus

Related Species

The Chestnut-collared Longspur is closely related to other species within the Calcarius genus, such as the Lapland Longspur (Calcarius lapponicus) and Smith’s Longspur (Calcarius pictus). These species share similar habitats and behaviors, though they are distinct in terms of plumage and geographic distribution.

Distribution and Range

The Chestnut-collared Longspur is native to North America, where it breeds in the prairies of Canada and the northern United States. During the winter, it migrates southward to the central and southern United States and into Mexico.

Global Distribution

Migration Patterns

The Chestnut-collared Longspur is a migratory bird, with distinct breeding and wintering ranges. It typically migrates southward in the fall, with large flocks often observed moving through the central United States.

Population and Conservation Status

The Chestnut-collared Longspur is currently classified as Near Threatened by the International Union for Conservation of Nature (IUCN). This classification reflects concerns about habitat loss and population declines in some areas, although the species remains relatively widespread.

Population Estimates

Habitat

The Chestnut-collared Longspur is primarily associated with open grassland habitats, particularly native prairies. These areas provide the low vegetation and bare ground that the species needs for foraging and nesting.

Habitat Preferences

• Breeding Habitat: Prefers native prairies with sparse vegetation, often selecting areas with a mix of grasses and bare ground. It is also found in agricultural fields that mimic these conditions.
• Winter Habitat: During winter, the species shifts to similar open habitats in the southern United States and northern Mexico, including grasslands, fallow fields, and deserts.

Impact of Habitat Loss

The loss of native prairie habitat due to agricultural expansion and urban development is a significant threat to the Chestnut-collared Longspur. Conservation efforts are focused on preserving and restoring these grassland ecosystems.

Behavior

The Chestnut-collared Longspur is a ground-dwelling bird, spending most of its time foraging on the ground. It is known for its distinctive flight displays during the breeding season and its social behavior during migration and winter.

Social Structure

During the breeding season, Chestnut-collared Longspurs are territorial, with males defending their nesting sites through song and flight displays. Outside of the breeding season, they are highly social, forming large flocks that can number in the thousands during migration and winter.

Vocalization and Communication

The male’s song is a key part of its breeding behavior, consisting of a series of trills and whistles delivered during flight displays. This song serves both to attract females and to deter rival males.

Feeding

The Chestnut-collared Longspur primarily feeds on seeds, particularly those of grasses and forbs, but it also consumes insects, especially during the breeding season when protein is needed for raising chicks.

Seasonal Feeding Habits

• Spring and Summer: Diet shifts toward insects, including beetles, grasshoppers, and caterpillars, which provide essential protein for chick development.
• Autumn and Winter: Seeds become the primary food source, with the birds often foraging in agricultural fields where grains and weed seeds are abundant.

Feeding Behavior

Chestnut-collared Longspurs forage on the ground, often in flocks. They are adept at finding seeds and insects in sparse vegetation and bare ground, which is why they prefer open grasslands and similar habitats.

Breeding

The breeding season for the Chestnut-collared Longspur begins in late spring, with nesting typically occurring in early summer. The species is known for its ground nests, which are well-camouflaged in the surrounding vegetation.

Breeding Characteristics

• Nesting: Nests are built on the ground, usually hidden in a tuft of grass or under a small shrub. The nest is a simple cup made of grass, lined with finer materials such as hair or feathers.
• Clutch Size: Typically 3-5 eggs.
• Egg Description: Pale blue or greenish, with fine speckles.
• Incubation Period: About 10-12 days, with the female primarily responsible for incubation.
• Fledging: Chicks leave the nest approximately 10 days after hatching but remain dependent on their parents for several more weeks.

Breeding Data

Threats

The primary threats to the Chestnut-collared Longspur include habitat loss, agricultural practices, and climate change. These factors have contributed to population declines, particularly in areas where native prairie has been converted to cropland.

Specific Threats

• Habitat Loss: The conversion of native prairie to agricultural land is the most significant threat, reducing available breeding and foraging habitat.
• Pesticides: The use of pesticides in agricultural areas can reduce insect populations, limiting food availability during the breeding season.
• Climate Change: Changes in climate may alter the availability of suitable habitats, particularly in the northern part of the species’ range.

Migration

The Chestnut-collared Longspur is a migratory species, with most individuals traveling from their breeding grounds in Canada and the northern United States to wintering areas in the central and southern United States and northern Mexico.

Migration Patterns

Conclusion

The Chestnut-collared Longspur is a remarkable bird, well-adapted to the grassland ecosystems of North America. Its striking breeding plumage, ground-dwelling habits, and migratory behavior make it a species of interest to both birdwatchers and conservationists. However, the loss of native prairie habitats poses a significant threat to its population, highlighting the need for continued conservation efforts. By understanding the ecology and needs of the Chestnut-collared Longspur, we can work to ensure that this beautiful bird remains a thriving part of our natural heritage.