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Graceful and Striking: Everything You Need to Know About the Black-winged Stilt

The black-winged stilt, or Himantopus himantopus, is a strikingly beautiful bird with long legs that seem to go on forever. In many cultures, the stilt is considered a symbol of elegance and grace.

The species is found on every continent except for Antarctica and breeds in wetlands, shallow lakes, and marshes. In this article, we will explore the identification of the black-winged stilt, its different plumages, and some key information about its breeding cycle and molts.

Identification

Field Identification

The black-winged stilt is easily recognized by its black and white plumage, long slender legs, and thin, delicate bill. The birds overall body color is mostly white with black feathers on its back, wings, and tail.

During the breeding season, the female stilt has a patch of chestnut feathers on its lower neck while the male only shows a tinge of chestnut color. Both sexes have red eyes with a black iris and bright pink legs.

The average length of the black-winged stilt is between 14 and 16 inches.

Similar Species

There are other species that resemble the stunning black-winged stilt, however, there are key differences to pay attention to. One of the most common ones is the Pied Avocet, which also has long, thin legs and a long, upturned bill.

However, the avocet has a mostly black and white plumage with no chestnut colors. The bill is also much longer and upturned.

Another bird species that can be confused with the black-winged stilt is the Black-necked Stilt, which is mostly found in South America. The black-necked stilt has a black neck with a white collar, while the black-winged stilt has a white neck.

Plumages

Juvenile black-winged stilts are not as distinctly colored as their parents. They have a brownish-black head and a brownish-gray body with a few black patches on their wings.

The juveniles will stay with their parents until they are healthy and strong enough to fly. As the bird matures, it will develop its striking black and white plumage.

Molts

The black-winged stilts breeding cycle and molts are strongly tied to water levels. The birds begin to molt their feathers in the autumn after the breeding season.

The breeding season for this species usually starts around March in the Northern Hemisphere, while in the Southern Hemisphere it starts around August. During the breeding period, the birds will slowly replace their feathers while caring for their young.

This period of molting is known as the pre-alternate molt. After the young birds have fledged and once the breeding season is over, Himantopus himantopus will begin their post-breeding molt.

During this period, the birds will replace their feathers with a brighter, more vibrant plumage that will help them during migration. Once the post-breeding molt is finished, the stilt will gain a more striking appearance with their black and white plumes fully developed.

Conclusion

In conclusion, the black-winged stilt is a stunning-looking bird found across the world’s wetlands, shallow lakes, and marshes. With its striking plumage and long, slender legs, this bird is easily identifiable.

There are other bird species that closely resemble the black-winged stilt, but they can be differentiated by some distinguishing features. Understanding the breeding cycle and molting cycles of the black-winged stilt is essential in studying how the bird species adapts to environmental factors.

The article provides a deeper understanding of this species, explores its unique plumages, and allows us to appreciate and admire the beauty of the black-winged stilt.

Systematics History

The classification of birds is constantly evolving, and as knowledge and technology progress, the study of bird species changes. The Black-winged Stilt or Himantopus himantopus classified under the family Recurvirostridae has undergone several changes in systematics history.

Geographic Variation

There are several subspecies of black-winged stilt that have been identified through their geographic distribution and slight differences in their physical appearance. Geographic variation can occur because of various aspects such as isolation events or genetic drift.

Subspecies

The black-winged stilt has six recognized subspecies:

1. Himantopus himantopus himantopus: found in Europe, and Western Asia.

They are the most notable subspecies and have a distinct white forehead and elongated feathers on the back and neck. 2.

Himantopus himantopus meridionalis: found in Southern Europe, Northern Africa, and the Canary Islands. This subspecies has a slightly smaller bill and a less-pronounced white forehead compared to the himantopus subspecies.

3. Himantopus himantopus maura: restricted to the Tiris and Senegal basins, West Africa.

The subspecies exhibits more extensively black on the back and less white on the belly. 4.

Himantopus himantopus knudseni: found in the Afrotropical realm ranging from Liberia to the north, Uganda in the center, and Zambia in the south. This subspecies has larger and more extensive black patches on the wings.

5. Himantopus himantopus schaferi: known from Malawi, Zimbabwe, and Mozambique.

They have the most remarkable white plumage on the forehead and have chestnut brown below the throat. 6.

Himantopus himantopus leucocephalus: found on the Solomon Islands, Saddle Islands, and coastal Papua New Guinea. They are larger than other subspecies and have incredibly striking pure white heads.

Related species

The black-winged stilt belongs to the Recurvirostridae family and are related to other species such as the American avocet, the pied avocet, and the black-necked stilt. The American avocet is found in North America and has similar physical features to the black-winged stilt with long, thin legs and a thin, upturned bill.

The pied avocet, on the other hand, has almost an entirely black and white plumage but still has the distinctive long, upturned bill and long legs. The black-necked stilt, which is found in South America, is also related to the black-winged stilt and is only distinguishable by its black neck and white collar.

Historical Changes to Distribution

The evolutionary distribution of the black-winged stilt or Himantopus himantopus is intriguingly complex as different subspecies of the bird have shown expansion and contraction patterns. The bird has a long history of dispersal and invasion in various parts of the world.

Fossils found in Spain suggest that the black-winged stilt has been in existence for over two million years. In the past, the bird’s distribution has been restricted to the Old World and had not migrated to the Americas until the 19th century.

The distribution of the black-winged stilt worldwide has been dynamic, with some subspecies suggesting speculation that there was contact between different populations. This speculation has been prompted by the study of mitochondrial DNA to understand genetic diversity patterns across geographic distribution and ensure accurate subspecies categorization.

Investigations showed that most of the taxonomic groups are related to a single subspecies, the Himantopus himantopus himantopus. In Africa, subspecies identification is challenging due to a high degree of interbreeding between different taxa.

More recently, due to increased human colonization of wetland habitats and fishing farming, the distribution of the black-winged stilt has also been affected. Further, human-induced habitat modification, destruction, and disturbance are emerging as factors driving the species’ range contraction in some areas.

Human activities are associated with the loss of key breeding, nesting, and feeding habitats factors that have severe effects on the welfare of the species.

Conclusion

In conclusion, the black-winded stilt is an enigmatic bird species that has undergone significant changes in systematics history due to the advancement of knowledge and technology. The different subspecies of this bird have distinct geographical distribution and can be distinguished by slight differences in their physical appearance.

Historical changes to the bird’s distribution have also occurred, and in recent times, human activities have impacted the black-winded stilt’s welfare and distribution by altering their habitat. The study of the systematics of the black-winged stilt sheds light on the evolution of bird species and the effects of human activities on wildlife populations.

Habitat

The black-winged stilt is widely distributed across wetland habitats, such as shallow lakes, marshland, and salt pans where they can forage on small aquatic invertebrates and amphibians. They are also observed in brackish estuaries, coastal salt pans, and tidal flats that provide a nesting area for the birds.

These versatile and attractive birds are found in both coastal and inland areas worldwide, such as Europe, North Africa, Australia, the Middle East, and the Indian subcontinent. Additionally, the black-winged stilt seems to prefer nesting in habitats that have minimal vegetation, where their eggs and chicks can easily be spotted by the parent birds.

Movements and Migration

Black-winged stilts move around inside their wetland habitat according to available resources, particularly water and food. During the breeding season, black-winged stilts exhibit local or sedentary movements.

On the other hand, during non-breeding seasons, they undertake some migration to locations with better feeding and climate conditions. The migration routes of black-winged stilts are a subject of intense study as many populations show different travel patterns and time-scales during the migration phase.

Still, important stop-over points in the periods before and after such movements have been identified. The Mediterranean Basin has been established as a significant stopover site for the Western Palearctic population and is crucial in understanding the bird’s migration cycles.

The migratory movements of black-winged stilts are influenced by weather conditions, breeding success, and habitat quality, which directly impact the species’ survival rates and long-term evolutionary success. The timing, distance, and direction of black-winged stilt migration primarily vary by geographic distribution or subspecies.

Birds breeding further north tend to migrate south to warmer areas during the winter months; for example, Himantopus himantopus himantopus from Europe will spend their winter in Africa. In contrast, birds breeding in the tropical regions tend to move or disperse during the non-breeding season within their wetland habitats but can make some local movements if necessary.

Migration also involves the birds crossing significant geographical barriers like water bodies, and performance during such events highlights species’ resilience and adaptability to changing conditions. The bird species exhibit very high flying abilities, and one individual bird migration from Botswana was tracked over a distance of c.

2340 kilometres to the Jalloh River Estuary in Sierra Leone.

Interestingly, black-winged stilts in southern hemisphere countries may show a migration trend different from that of European birds.

For example, the migration habits of the birds found in south-western Australia appear to be more closely tied to the breeding cycle; they display sedentary behaviors, only moving to higher up breeding grounds during the breeding period. The timing of migration can also be influenced by food availability and predation risk, as black-winded stilts can become completely diurnal during migration to prevent predators from attacking.

Other factors, such as changes to their breeding grounds during the non-breeding period, may also influence migration patterns.

Conclusion

The black-winged stilt moves around their wetland habitats seasonally to avoid harsh environmental conditions and secure food sources. Migration for the black-winged stilt is usually undertaken on a local rather than global scale, with birds moving between wetland habitats over shorter distances and on a regional basis to enhance population health.

In southern hemisphere populations, the birds show sedentary behavior, only moving up breeding grounds for the breeding period. Understanding the bird’s movement and migration patterns is crucial in formulating management strategies that promote the species’ well-being and long-term survival.

It is also an area that needs continued research to enable an in-depth understanding of these fascinating birds’ ecology and behaviors.

Diet and Foraging

Feeding

The black-winged stilt is an active forager, and its long legs, flexible neck, and long, thin bill make it well adapted for hunting small aquatic prey. They move slowly and delicately through shallow water, often stalking and capturing prey with quick strikes of their bills.

They are also known to wade in water, using their wings to maintain balance, while flipping their bills back and forth to disturb small invertebrates in the sediment and then catching them. In deeper water or while pursuing prey, the birds will swim while holding their bodies nearly parallel to the water surface.

Diet

The black-winged stilt feeds mainly on a wide range of aquatic invertebrates such as beetles, flies, crustaceans, worms, and mollusks. Young black-winged stilts prefer smaller prey, while adults are opportunistic and eat a wider range of prey of varying sizes.

The bird’s diet varies according to the time of day, abundance of prey, environmental factors, and time of year. For example, during migration, the bird may change its diet based on what is available at different stop-over locations along the way.

Metabolism and Temperature Regulation

Black-winged stilts have a high metabolism and require a good supply of food to maintain their energy levels. This high metabolic rate is important for the birds to maintain their body temperature, which is around 41C.

Although the birds have a double layer of feathers, they also have to regulate their body temperature by panting and cooling themselves down by splashing water onto their bodies. The birds also have an adaptation in their respiratory system, which allows for more oxygen intake, minimizing heat production, and making thermoregulation easier.

Sounds and Vocal Behavior

Vocalization

Black-winged stilts have various sounds that they use in different social contexts, mainly during courtship, display, alarm, and distress. The vocalizations are primarily used to communicate about breeding site locations, food resources, predators, and family status.

The species has a range of calls that they use depending on the purpose; one of these sounds is the long downward whistle that is used during flight. The bird’s call may differ between subspecies and may also be influenced by geography, habitat type, and social context.

Adult black-winged stilts will sometimes use vocalizations to alert and guide their young about potential dangers. This can be done through variation in the pitch, duration, and intensity of the sounds produced, which can quickly be picked up by their young.

Another vocalization used by the black-winged stilt is the ear-piercing, high-pitched alarm call, which is used in response to danger. The alarm call is a distinct “kyip, kyip” sound, and when the call is made, it often leads to the whole group of birds fleeing the area in response.

The pitch and duration of the alarm call may vary depending on the degree of danger perceived by the birds. During courtship displays, black-winged stilts emit an unusual vocalization, a high-pitched, drawn-out, and descending “sweeee” sound.

The call, which is unlike any other sound made by the bird, can be made by either a male or a female black-winged stilt. The sound is a crucial part of the courtship display as it is used to establish a bond between the pair and as an indication of being ready to mate.

Research has shown that the birds tend to call alternately during the courtship display in a coordinated fashion.

Conclusion

In conclusion, the black-winged stilt is an active forager with an extensive diet that mainly consists of aquatic invertebrates. They have a high metabolic rate, which they regulate through panting and splashing while maintaining their body temperature.

Vocalizations are used in social communication, with various calls used in different social contexts. The calls made during courtship displays are essential in enhancing individual pair bonding and coordination, while alarm calls are crucial in warning of danger.

Understanding the black-winged stilt’s vocal behavior and feeding patterns is a critical component of the species’ deeper understanding. Additionally, continued efforts to study these birds will provide valuable insight into their behaviors and help establish conservation strategies for species survival.

Behavior

Locomotion

Black-winged stilts are well-adapted for locomotion both on land and on water. They are capable of running quickly over the ground, even on very muddy terrain, while keeping their long legs and thin bodies steady high above the mud.

They are so well adapted for this that they can even swim through the water quite efficiently while keeping their slender bodies almost parallel to the surface of the water, using their long legs to paddle themselves along.

Self-Maintenance

Black-winged stilts have distinct cleaning behavior that is vital for their survival. They regularly run their bills through and over their feathers to keep them clean and fluffed out to aid in their insulation.

This behavior is essential in reducing the risk of bacterial infections that may be incurred through damp feathers.

Agonistic Behavior

Black-winged stilts can be extremely territorial during the breeding season, which not only affects intra-species but also interspecific competition for resources. Sometimes birds will defend large territories, which can be several hundred meters in size, and several groups of males will often challenge each other.

The birds use displays, such as wing-spreading and stylized walks, to assert their territorial dominance.

Sexual Behavior

Breeding

Black-winged stilts have paired and monogamous

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