Bird O'clock

Discover the Fascinating World of Black-Tailed Godwits: Their Behavior Migration and Conservation

Black-tailed Godwit, also known as Limosa limosa, is a migratory bird that belongs to the family Scolopacidae. These birds can be found all over Europe and Asia, and they are known for their long legs and bill, which they use to feed in shallow waters.

Identification:

Field Identification:

Black-tailed Godwits are a medium-sized bird, measuring about 37-41 cm in length, with a wingspan of 70-90 cm. They are known for their long, straight bill that curves slightly upward, and their long legs.

They have a brownish-grey color on their upper body, with a reddish-brown head and neck, and a white belly. Similar Species:

Black-tailed Godwits can be confused with a number of other shorebirds, including the Marbled Godwit, Bar-tailed Godwit, and Hudsonian Godwit.

However, Black-tailed Godwits can be distinguished from these other species by their longer and straighter bill, shorter legs, and their distinctive tail pattern when in flight. Plumages:

Black-tailed Godwits have two different plumages – breeding plumage and non-breeding plumage.

During the breeding season, the birds have a more vibrant coloration, with a rusty-red head and neck, and a black-barred belly. In their non-breeding plumage, they have a more muted coloration, with a greyish-brown head and neck, and a plain belly.

Molts:

Black-tailed Godwits undergo two molts in a year – the prebasic molt and the prealternate molt. During the prebasic molt, which takes place after the breeding season, the birds replace their feathers for the winter months.

During the prealternate molt, which takes place before the breeding season, the birds replace their feathers to prepare for the breeding season. In conclusion, Black-tailed Godwits are a fascinating and beautiful species of shorebirds.

Their long bill, legs, and distinctive plumage make them easily identifiable in the field. Understanding their identification and molting patterns can help birders to better appreciate these lovely birds and contribute to their conservation.

Systematics History

The Black-tailed Godwit (Limosa limosa) is a long-distance migratory bird, which can be found breeding throughout northern Europe and Eurasia. Its systematics history dates back to the 18th century when it was first described by Linnaeus in 1758.

Since then, the bird has undergone extensive scientific research and reclassification.

Geographic Variation

Black-tailed Godwits exhibit significant geographic variation, both in plumage and body sizes. The variation in plumage is more evident between the sexes, with males having a more vibrant and brighter chestnut-red color, while females have a more subdued plumage.

The size variation is more prominent between subspecies, with birds from the northernmost areas being larger than those from southern regions.

Subspecies

There are four recognized subspecies of Black-tailed Godwits:

1. L.

l. limosa: The nominate subspecies breeds in Iceland, Great Britain, Northwest Russia, and parts of Scandinavia.

It is the largest subspecies, with larger body size and a more orange-red breeding plumage. 2.

L. l.

islandica: This subspecies breeds exclusively in Iceland. It is slightly smaller in size than the nominate subspecies, has a brighter breeding plumage, and a longer, slender bill.

3. L.

l. taymyrensis: This subspecies breeds in the Taimyr Peninsula of Siberia and has a larger body size than the two previously mentioned subspecies.

Its breeding plumage is distinct, with a more cinnamon color. 4.

L. l.

melanuroides: This subspecies was originally described as a distinct species but is now considered a subspecies of Black-tailed Godwit. It breeds in the western Himalayas and has a relatively smaller body size and a lighter-colored breeding plumage.

Related Species

Black-tailed Godwit has a close relation to Bar-tailed Godwit (Limosa lapponica) and also, to a lesser extent, the Hudsonian Godwit (Limosa haemastica). Black-tailed and Bar-tailed Godwits have a significant overlap in their breeding areas, whereas the Hudsonian Godwit breeds exclusively in North America.

Historical Changes in Distribution

In the early 20th century, Black-tailed Godwits bred in large numbers throughout Europe, with Iceland being the most significant breeding ground. However, this population drastically declined, mainly due to habitat loss caused by drainage and reclamation of the wetlands and increased intensification of agriculture.

In response, conservation efforts were introduced in the mid-1990s, and with the help of agri-environment schemes, the population started to recover. In contrast, there has been a recent increase in the breeding population in the Netherlands, which is attributed to the management of marshy agricultural land.

The country’s third largest colony has developed in the Oostvaardersplassen, a man-made wetland area. This region was created as a buffer zone for Amsterdam airport, but its management for grazing and wetland habitats has turned it into one of the most spectacular birding sites in the Netherlands.

During migration, Black-tailed Godwits can be spotted in various wetland habitats, including mudflats, salt pans, and marshes. The species’ IUCN status is of least concern, with a global population estimated at around 260,000 individuals.

Conclusion

The Black-tailed Godwit is a migratory wader bird that breeds in northern Europe and Eurasia. The species has undergone extensive scientific research and has been reclassified over time.

The bird exhibits significant geographic variation, both in plumage and body sizes, with four recognized subspecies. Historical changes in distribution have impacted the species’ breeding trends, but conservation efforts have increased the breeding population in some regions.

The Black-tailed Godwit remains an integral part of the wetland ecosystem, and further conservation efforts should be implemented to ensure its continued success. Habitat:

Black-tailed Godwits prefer to inhabit wetland habitats, including shallow freshwater marshes, bogs, and estuaries with extensive mudflats, usually with enough vegetation to provide breeding grounds.

These habitats support the millions of invertebrates on which the birds feed, as well as providing cover and sites for nesting, displaying, and roosting. Throughout their range, the Black-tailed Godwit depends on the availability of these habitats and sites for successful breeding, rest, and foraging.

During the breeding season, Black-tailed Godwits need wet grasslands for nesting and feeding. These wet grasslands are often intensively cultivated, which can affect the species’ breeding habitat quality negatively.

Once breeding is over, Black-tailed Godwits move to coastal areas for winter, especially coastal mudflats, where they spend the non-breeding months, resting, and feeding. These habitats are often highly productive, providing an abundant source of food for the birds.

Movements and Migration:

Black-tailed Godwits are long-distance migratory birds, covering impressive distances annually. They breed in northern Europe and Russia, and migrate to their wintering grounds in Africa, ranging from the United Kingdom and France in the west to Senegal and Gambia in the east.

Studies have shown that Black-tailed Godwits’ migration patterns are somewhat variable, with some individuals opting for a shorter westward migration, while others prefer the longer, eastward route. The westward route involves cutting over the seas to Iberian and, on occasion, West African coasts before heading south, while the Eastward route involves a much longer flight over the Balkans, Turkey, the Middle East, and the Arabian Peninsula before reaching East Africa.

Immature birds tend to take longer before making their first migration, with most individuals deferring until their second or third year. Others, however, migrate as early as their first year, joining large flocks of adult Black-tailed Godwits to team up for the long flight south.

While migrating, Black-tailed Godwits’ over-land journey may take several days. Still, they can cross the Sahara Desert with only a single nonstop flight lasting, in some cases, more than 60 hours.

Some individuals have been known to make annual migrations of up to 15,000km, mostly during October and November and returning in March and April. Throughout the migration period, Black-tailed Godwits face numerous threats, including human activities such as this habitat loss, hunting, adverse climate, land use, and the inability of species’ populations to withstand heavy harvests.

The species’ migration patterns may also be adversely affected by climate change, which leads to changes in the availability, timing, and distribution of the insects they feed on. Migration presents a significant challenge for these birds, and many do not complete the journey, particularly in areas where habitat loss and hunting are a problem.

Conclusion:

Black-tailed Godwits are migratory birds, and their population depends on suitable breeding grounds during the breeding season, and coastal wetland habitats’ availability during the non-breeding season. The species undertakes massive seasonal movements, migrating over thousands of kilometers annually.

During migration, Black-tailed Godwits face numerous threats, including habitat loss due to human activities, hunting, climate change, and the bird’s inability to survive heavy harvesting in certain areas. To ensure the long-term survival of Black-tailed Godwits, there is a significant need for transboundary conservation efforts to protect the species and its habitats throughout the world.

Diet and Foraging:

Feeding:

Black-tailed Godwits forage by probing mud, sand, or soft soil to find and capture their prey. The probing method involves thrusting their long bills deep into the mud to search for worms, insects, crustaceans, mollusks, and other invertebrates.

The bird’s sensitive bills have specialized nerve endings that allow the detection of prey by sensing the vibrations produced by the creature’s movements. Diet:

Black-tailed Godwits are opportunistic feeders, and the type of food they consume depends on the availability within their habitats.

At times when invertebrates, especially earthworms, are in abundance, they become a significant part of the bird’s diet. While on their wintering grounds, the birds’ foraging habitats may vary from intertidal mudflats to agricultural fields, wetlands, and grasslands.

Metabolism and Temperature Regulation:

Black-tailed Godwits are endothermic animals, meaning that they regulate their body temperatures internally. They have a high metabolic rate, which is necessary for their survival and allows them to maintain a consistent body temperature.

This adaptation is critical because of their migratory lifestyle, which exposes them to varying and sometimes extreme environmental temperatures. During the breeding season, Black-tailed Godwits adjust their metabolic rate to suit their breeding activity requirements.

They experience a rapid increase in metabolic rate, which allows the female bird to develop and produce nutrients-rich eggs. Additionally, they store fat reserves, which provides them with the necessary energy for migration.

In contrast, there is a significant reduction in metabolic rate during the non-breeding season to conserve energy. Sounds and Vocal Behavior:

Vocalization:

Black-tailed Godwits use a range of vocalizations to communicate with each other during the breeding season, migration, and wintering.

These vocalizations include calls and songs, and the sounds that the birds produce vary, depending on the situation and context. Black-tailed Godwits produce alarm calls, which they use to alert other birds of nearby predators or to identify potential threats.

This call is a loud, harsh ‘grit grit’ sound that is typically accompanied by a raised posture and head feathers, indicating a heightened awareness of danger. Their songs, however, are more musical and are produced during the breeding season, specifically by males to attract females.

The Black-tailed Godwit’s song is a series of notes repeated several times, consisting of a ‘tu-ella’ downslurred call, which ends with a ‘churr’ or a low, trilling sound. In addition to songs and calls, Black-tailed Godwits also use a range of non-vocal sounds, such as aerial displays, which involve the birds performing synchronized flight patterns.

During these displays, they produce complex wing-whirring sounds, which may be produced by the noise made as the wings flap together.

Conclusion:

Black-tailed Godwits are an interesting species of migratory birds that have adapted to suit their foraging and temperature regulation needs. They have a high metabolic rate, which allows them to maintain a consistent body temperature, adapt to the breeding season’s metabolic demands and build up fat reserves for the migration period.

Black-tailed Godwits use a range of vocalizations to communicate with other birds, with the songs used by males during breeding being particularity notable. The various vocalizations and non-vocal sounds produced by the birds are used to alert each other of potential threats, identify each other, and communicate effectively.

Overall, Black-tailed Godwits have a fascinating way of foraging and communicating, which has allowed them to survive in their specific habitats and undertake long-distance migrations annually. Continued conservation efforts would help ensure the sustainability of this species.

Behavior:

Locomotion:

Black-tailed Godwits are active birds that can move quickly both on land and in water. During their feeding and foraging activities, they can be seen probing mud or soil with their long bills while walking slowly on the wetlands or swimming and wading in shallow water.

In the air, Black-tailed Godwits are swift flyers with a distinctive rapid wingbeat. They typically fly in a V-formation during their long-distance migration, which helps them to use less energy, improves their aerodynamics, and allows them to communicate and navigate more effectively.

Self Maintenance:

Like all birds, Black-tailed Godwits need to maintain their feathers and bodies in good condition for efficient flight, insulation, and protection. They do this through preening, a process that entails cleaning, grooming, and rearranging their feathers.

Preening removes dirt, dust, and parasites that might stick to their feathers and can also help to align the feathers and shape them for efficient flight. Black-tailed Godwits accomplish this through the use of their bill, which they use to groom and clean their feathers.

Agonistic Behavior:

Black-tailed Godwits are relatively peaceful birds, but conflicts do arise, especially during the breeding season. These can stem from aggressive behavior over nesting sites, territory, or resources.

Agonistic behavior includes threats, vocalizations, and ritualized posturing, where the birds make themselves appear larger than they are, with erect head feathers, spread wings, or raised tails, in order to intimidate the other bird. Sexual Behavior:

Black-tailed Godwits are monogamous birds, and they form life-long pair bonds.

During the breeding season, the males initiate mating by guarding a territory or a nesting site and attract females through aerial displays, calling, and posturing. Once a female chooses a mate, they form a pair bond, and both birds contribute to nest building and incubation.

Females lay 3-4 eggs in a depression in the ground, usually lined with grasses, feathers, and other plant materials. Both parents take turns incubating the eggs, which hatch after around 23-27 days.

Breeding:

Black-tailed Godwits typically breed in temperate and subarctic regions of Eurasia, which provide a suitable breeding habitat. They perform elaborate aerial displays during breeding, with males usually flying higher into the air than females.

During mating, the male bird may offer a gift of food, usually prey items, in an event referred to as courtship feeding, which often cements the pair bond. The female bird incubates the eggs, which take around three to four weeks to hatch, with the chicks being fully feathered and able to move around and feed on their own within a few days after hatching.

Demography and Populations:

The Black-tailed Godwit is a widespread, abundant species, with a global population estimated at around 390,000 individuals. While some populations, especially those breeding in Britain and Ireland and Iceland, have declined significantly, others, such as those in the Netherlands, have increased in number.

The species is of least concern on the IUCN Red List, but conservation efforts must be sustained, especially for populations that are threatened with habitat loss or degradation. Additionally, the understanding of demographic processes, population structure, and migration patterns of these birds is necessary for the development of effective conservation strategies.

Conclusion:

In conclusion, Black-tailed Godwits exhibit a variety of interesting behaviors, including movement, self-maintenance, sexual behavior, and agonistic behavior. They are fascinating birds, with a complex migratory lifestyle and an adaptiveness to their unique habitats.

The breeding characteristics of Black-tailed Godwits, which includes long-term monogamy and pair bonding, as well as elaborate aerial displays and courtship feeding behavior, make them a unique species in the avian world. Finally, thanks to the conservation efforts to date, the global population of the Black-tailed Godwit is healthy, with most populations stable or increasing.

Nevertheless, further research into their demographic processes, population structure, and migration patterns remains vital to the continued survival of the species.

The Black-tailed Godwit is a migratory bird that inhabits wetlands and estuaries across

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