The philomachus pugnax is a fairly large wader, difficult to distinguish from other nearby species. Its most characteristic feature is the colorful nuptial attire worn by the males, which are adorned with striking feathered head tufts, with which, through stereotyped postures, dances and wing movements, they confront other males in endless fights, hence the name of the species, for the females.
Philomachus pugnax is a medium-sized wading bird that breeds in marshes and wet meadows of northern Eurasia. This highly gregarious shorebird is migratory and sometimes forms large flocks in its wintering grounds, which include southern and western Europe, Africa, southern Asia, and Australia.
The philomachus pugnax is a long-necked, broad-bellied bird. This species shows marked sexual dimorphism; the male is much larger than the female (the sleeve), and has a breeding plumage that includes brightly colored head tufts, orange facial skin, extensive black breast color, and the large collar of ornamental feathers that inspired this bird’s English name.
The female and non-breeding male have grayish-brown upperparts and mostly white underparts. Three different feathered male types, including a rare form that mimics the female, use a variety of strategies to obtain mating opportunities on a lek, and colorful head and neck feathers stand as part of the elaborate main courtship display.
The female has one brood per year and lays four eggs in a well-hidden nest on the ground, incubating the eggs and raising the chicks, which are mobile soon after hatching, on her own. Predators of wader chicks and eggs include mammals such as foxes, stray cats, and stoats, and birds such as large gulls, corvids, and skuas.
The philomachus pugnax feeds in damp grasslands and soft mud, exploring or searching by sight for edible items. It feeds primarily on insects, especially in the breeding season, but consumes plant material, including rice and corn, in migration and in winter. Classified as “least concern” in the IUCN Red List criteria, global conservation concern is relatively low due to the large number of individuals breeding in Scandinavia and the Arctic. ( See Article: Agapornis Canus )
However, the range in much of Europe is contracting due to land drainage, increased fertilizer use, loss of mowed or grazed breeding sites, and overhunting. This decline has been reflected in the Agreement on the Conservation of African-Eurasian Migratory Waterbirds (AEWA).
Taxonomy and nomenclature
Philomachus pugnax is a wader of the large family Scolopacidae, the typical shorebirds. Recent research suggests that its closest relatives are the broad-billed sandpiper, Calidris falcinellus, and the sharp-tailed sandpiper, Calidris acuminata. It has no recognized subspecies or geographic variants.
This species was first described by Carl Linnaeus in his Systema Naturae in 1758 as Tringa pugnax. It was transferred to its present genus by the German naturalist Blasius Merrem in 1804. Both parts of the binomial name refer to the bird’s aggressive behavior in its mating areas; pugnax from the Latin term for “combative”.
The original English name for this bird, dating from at least 1465, is ree, perhaps derived from a dialectic term meaning “frantic”; a later name reeve, still used for the female, is of unknown origin, but may be derived from shire-reeve, a feudal official, comparing the male’s flamboyant plumage to the officer’s robes. The present name was first recorded in 1634, and is derived from the collar, an exaggerated collar in fashion from the mid-16th to the mid-17th century, as the ornamental feathers on the male bird’s neck resembled the collar’s clothing.
Description of philomachus pugnax
Philomachus pugnax has a distinctive saucy appearance, with a small head, medium bill, elongated neck and pot-bellied body. It has long legs of variable color but usually yellow or orange. In flight, it has a deeper, slower wingbeat than other waders of similar size, and displays a thin, indistinct white wing bar, and white ovals on the sides of the tail.
This species shows sexual dimorphism. Although a small percentage of males resemble females, the typical male is much larger than the female and has elaborate breeding plumage. It is 29-32 cm (11-13 inches) long with a wingspan of 54-60 cm (21-24 inches) and weighs about 180 g (6.3 ounces). In the breeding season from May to June, the male’s typical legs, bill and bare, warty facial skin are orange, and he has distinctive tufts on the head and a ruff on the neck.
These ornaments vary among birds, whether black, chestnut or white, with solid, lattice or patchy coloration. The gray-brown back has a scaly pattern, often with black or chestnut feathers, and the underparts are white with extensive black on the breast.The extreme variability of the main breeding plumage is believed to have developed to aid individual recognition in a species that has communal breeding displays, but is generally mute.
Outside the breeding season, typical male head and neck decorations and bare facial skin are lost and the legs and bill become duller. The upperparts are gray-brown, and the underparts are white with gray spots on the breast and flanks.
The female, or “reeve”, is 22-26 cm (8.7-10.2 in) long with a wingspan of 46-49 cm (18-19 in), and weighs about 110 g (3.9 oz). In breeding plumage it has a gray-brown upperparts with white-edged feathers and a dark center. The breast and flanks are variably spotted black. In winter, its plumage is similar to that of the male, but the sexes are distinguished by their size. The plumage of the juvenile fledgling resembles that of the non-breeding adult, but has cleanly patterned, scaly upperparts with dark feather centers, and a strong buff tinge on the underparts.
Typical adult males begin to molt before returning to breeding areas, and the proportion of birds with head and neck decorations gradually increases throughout the spring. Second-year birds lag behind adults in the development of breeding plumage. They have a lower body mass and slower weight gain than full adults, and perhaps the demands made on their energy reserves during the migration flight are the main reason for the delay in molt.
Ruffs of both sexes have an additional molt stage between winter plumage and late summer, a phenomenon also observed in the plover-tailed godwit. Before developing full finery with ruffs and colorful tufts, males replace part of their winter plumage with striped feathers. Females also develop a mixture of winter and striped feathers before reaching their summer appearance.
The male’s final breeding plumage is the result of replacing both winter and striped feathers, but the female retains the striped feathers and replaces only the winter feathers to achieve her summer plumage. The striped prenuptial plumages may represent the original breeding appearance of this species, the striking nuptial feathers of the male evolving later under strong sexual selection pressures.
Adult males and most adult females begin their pre-winter molt before returning south, but complete most feather replacements on wintering grounds. In Kenya, males molt 3-4 weeks earlier than females, finishing before December, while females typically complete feather replacement during December and early January.
Juveniles molt from their first summer body plumage to their winter plumage in late September to November, and later undergo a prebreeding molt similar in timing and duration to that of adults, and often produce a brightly colored appearance. ( See Article: Corn Duck )
Two other waders can be confused with philomachus pugnax. The juvenile sharp-tailed sandpiper is slightly smaller than a juvenile female ruff and has a similar rich orange breast, but the ruff is slimmer with a longer neck and legs, a more rounded head, and a much smoother face. The high-breasted sandpiper also resembles a small juvenile ruff, but even the female ruff is noticeably larger than the sandpiper, with a longer bill, rounder body, and scaly upperparts.